SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Hegardt Cecilia) "

Sökning: WFRF:(Hegardt Cecilia)

  • Resultat 1-50 av 58
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Borgström, Björn, et al. (författare)
  • Structure–Activity Relationships in Salinomycin : Cytotoxicity and Phenotype Selectivity of Semi-synthetic Derivatives
  • 2017
  • Ingår i: Chemistry - A European Journal. - : Wiley. - 0947-6539. ; 23:9, s. 2077-2083
  • Tidskriftsartikel (refereegranskat)abstract
    • The ionophore salinomycin has attracted attention for its exceptional ability to selectively reduce the proportion of cells with stem-like properties in cancer cell populations of varying origin. Targeting the tumorigenicity of such cells is of interest as they are implicated in recurrence, metastasis, and drug resistance. Structural derivatives of salinomycin are thus sought after, both as tools for probing the molecular mechanism(s) underlying the observed phenotype effects, and for improving selectivity and activity against cancer stem cells. Synthetic strategies for modification of each of the directly accessible functional groups of salinomycin are presented and the resulting library of analogues was investigated to establish structure–activity relationships, both with respect to cytotoxicity and phenotype selectivity in breast cancer cells. 20-O-Acylated derivatives stand out by exhibiting both improved selectivity and activity. Mechanistically, the importance of the ionophore properties of salinomycin is highlighted by a significant loss of activity by modifications directly interfering with either of the two primary ion coordinating motifs in salinomycin, the C11 ketone and the C1 carboxylate.
  •  
2.
  • Borgström, Björn, et al. (författare)
  • Synthetic modification of salinomycin: selective O-acylation and biological evaluation
  • 2013
  • Ingår i: Chemical Communications. - : Royal Society of Chemistry (RSC). - 1364-548X .- 1359-7345. ; 49:85, s. 9944-9946
  • Tidskriftsartikel (refereegranskat)abstract
    • Salinomycin has found renewed interest as an agent for prevention of cancer recurrence through selectively targeting cancer stem cells. Strategies for generation of improved salinomycin analogs by individual modification of its hydroxyl groups are presented. An evaluation of the dose-response effects of the resulting library on breast cancer cell lines shows that acylation of the C20 hydroxyl can be used to improve IC50 values down to one fifth that of salinomycin.
  •  
3.
  • Brueffer, Christian, et al. (författare)
  • Abstract P4-09-03: On the development and clinical value of RNA-sequencing-based classifiers for prediction of the five conventional breast cancer biomarkers: A report from the population-based multicenter SCAN-B study
  • 2018
  • Ingår i: Cancer research. Supplement. - 1538-7445. ; 78:4
  • Konferensbidrag (refereegranskat)abstract
    • Background:In early breast cancer, five histopathological biomarkers are part of current clinical routines and used for determining prognosis and treatment: estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor 2 (ERBB2/HER2), Ki67, and Nottingham histological grade (NHG). We aimed to develop classifiers for these biomarkers based on tumor mRNA-sequencing (RNA-seq), compare classification performance to conventional histopathology, and test whether RNA-seq-based predictors could add value for patient risk-stratification.Patients and Methods:In total, 3678 breast tumors were studied. For 405 breast tumors in the training cohort, a comprehensive histopathological biomarker evaluation was performed by three pathology readings to estimate inter-pathologist variability on the original diagnostic slides as well as on repeat immunostains for this study, and the consensus biomarker status for all five conventional biomarkers was determined. Whole transcriptome gene expression profiling was performed by RNA-sequencing on the Illumina platform. Using RNA-seq-derived tumor gene expression data as input, single-gene classifiers (SGC) and multi-gene classifiers (MGC) were trained on the consensus pathology biomarker labels. The trained classifiers were tested on an independent prospective population-based series of 3273 primary breast cancer cases from the multicenter SCAN-B study with median 41 months follow-up (ClinicalTrials.gov identifier NCT02306096), and classifications were evaluated by agreement statistics and by Kaplan-Meier and Cox regression survival analyses.Results:For the histopathological evaluation, pathologist evaluation concordance was high for ER, PgR, and HER2 (average kappa values of .920, .891, and .899, respectively), but moderate for Ki67 and NHG (.734 and .581). Classification concordance between RNA-seq classifiers and histopathology for the independent 3273-cohort was similar to that within histopathology assessments, with SGCs slightly outperforming MGCs. Importantly, patients with discordant results, classified as hormone responsive (HoR+) by histopathology but non-hormone responsive by MGC, presented with significantly inferior overall survival compared to patients with concordant results. These results extended to patients with no adjuvant systemic therapy (hazard ratio, HR, 4.54; 95% confidence interval, CI, 1.42-14.5), endocrine therapy alone (HR 3.46; 95% CI, 2.01-5.95), or receiving chemotherapy (HR 2.57; 95% CI 1.13-5.86). For HoR+ cases receiving endocrine therapy alone, the MGC HoR classifier remained significant after multivariable adjustment (HR 3.14; 95% CI, 1.75-5.65).Conclusions:RNA-seq-based classifiers for the five key early breast cancer biomarkers were generally equivalent to conventional histopathology with regards to classification error rate. However, when benchmarked using overall survival, our RNA-seq classifiers provided added clinical value in particular for cases that are determined by histopathology to be hormone-responsive but by RNA-seq appear hormone-insensitive and have a significantly poorer outcome when treated with endocrine therapy alone
  •  
4.
  • Brueffer, Christian, et al. (författare)
  • Clinical Value of RNA Sequencing–Based Classifiers for Prediction of the Five Conventional Breast Cancer Biomarkers: A Report From the Population-Based Multicenter Sweden Cancerome Analysis Network—Breast Initiative
  • 2018
  • Ingår i: JCO Precision Oncology. - 2473-4284. ; 2, s. 1-18
  • Tidskriftsartikel (refereegranskat)abstract
    • PurposeIn early breast cancer (BC), five conventional biomarkers—estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor 2 (HER2), Ki67, and Nottingham histologic grade (NHG)—are used to determine prognosis and treatment. We aimed to develop classifiers for these biomarkers that were based on tumor mRNA sequencing (RNA-seq), compare classification performance, and test whether such predictors could add value for risk stratification.MethodsIn total, 3,678 patients with BC were studied. For 405 tumors, a comprehensive multi-rater histopathologic evaluation was performed. Using RNA-seq data, single-gene classifiers and multigene classifiers (MGCs) were trained on consensus histopathology labels. Trained classifiers were tested on a prospective population-based series of 3,273 BCs that included a median follow-up of 52 months (Sweden Cancerome Analysis Network—Breast [SCAN-B], ClinicalTrials.gov identifier: NCT02306096), and results were evaluated by agreement statistics and Kaplan-Meier and Cox survival analyses.ResultsPathologist concordance was high for ER, PgR, and HER2 (average κ, 0.920, 0.891, and 0.899, respectively) but moderate for Ki67 and NHG (average κ, 0.734 and 0.581). Concordance between RNA-seq classifiers and histopathology for the independent cohort of 3,273 was similar to interpathologist concordance. Patients with discordant classifications, predicted as hormone responsive by histopathology but non–hormone responsive by MGC, had significantly inferior overall survival compared with patients who had concordant results. This extended to patients who received no adjuvant therapy (hazard ratio [HR], 3.19; 95% CI, 1.19 to 8.57), or endocrine therapy alone (HR, 2.64; 95% CI, 1.55 to 4.51). For cases identified as hormone responsive by histopathology and who received endocrine therapy alone, the MGC hormone-responsive classifier remained significant after multivariable adjustment (HR, 2.45; 95% CI, 1.39 to 4.34).ConclusionClassification error rates for RNA-seq–based classifiers for the five key BC biomarkers generally were equivalent to conventional histopathology. However, RNA-seq classifiers provided added clinical value in particular for tumors determined by histopathology to be hormone responsive but by RNA-seq to be hormone insensitive.
  •  
5.
  •  
6.
  • Brueffer, Christian, et al. (författare)
  • The Mutational Landscape of the SCAN-B Real-World Primary Breast Cancer Transcriptome
  • 2020
  • Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
    • Breast cancer is a disease of genomic alterations, of which the complete panorama of somatic mutations and how these relate to molecular subtypes and therapy response is incompletely understood. Within the Sweden Cancerome Analysis Network–Breast project (SCAN-B; ClinicalTrials.govNCT02306096), an ongoing study elucidating the tumor transcriptomic profiles for thousands of breast cancers prospectively, we developed an optimized pipeline for detection of single nucleotide variants and small insertions and deletions from RNA sequencing (RNA-seq) data, and profiled a large real-world population-based cohort of 3,217 breast tumors. We use it to describe the mutational landscape of primary breast cancer viewed through the transcriptome of a large population-based cohort of patients, and relate it to patient overall survival. We demonstrate that RNA-seq can be used to call mutations in important breast cancer genes such asPIK3CA,TP53, andERBB2, as well as the status of key molecular pathways and tumor mutational burden, and identify potentially druggable genes in 86.8% percent of tumors. To make this rich and growing mutational portraiture of breast cancer available for the wider research community, we developed an open source web-based application, the SCAN-B MutationExplorer, accessible athttp://oncogenomics.bmc.lu.se/MutationExplorer. These results add another dimension to the use of RNA-seq as a potential clinical tool, where both gene expression-based and gene mutation-based biomarkers can be interrogated simultaneously and in real-time within one week of tumor sampling.
  •  
7.
  • Brueffer, Christian, et al. (författare)
  • The mutational landscape of the SCAN‐B real‐world primary breast cancer transcriptome
  • 2020
  • Ingår i: EMBO Molecular Medicine. - : EMBO. - 1757-4684 .- 1757-4676. ; 12:10
  • Tidskriftsartikel (refereegranskat)abstract
    • Breast cancer is a disease of genomic alterations, of which the panorama of somatic mutations and how these relate to subtypes and therapy response is incompletely understood. Within SCAN‐B (ClinicalTrials.gov: NCT02306096), a prospective study elucidating the transcriptomic profiles for thousands of breast cancers, we developed a RNA‐seq pipeline for detection of SNVs/indels and profiled a real‐world cohort of 3,217 breast tumors. We describe the mutational landscape of primary breast cancer viewed through the transcriptome of a large population‐based cohort and relate it to patient survival. We demonstrate that RNA‐seq can be used to call mutations in genes such as PIK3CA, TP53, and ERBB2, as well as the status of molecular pathways and mutational burden, and identify potentially druggable mutations in 86.8% of tumors. To make this rich dataset available for the research community, we developed an open source web application, the SCAN‐B MutationExplorer (http://oncogenomics.bmc.lu.se/MutationExplorer). These results add another dimension to the use of RNA‐seq as a clinical tool, where both gene expression‐ and mutation‐based biomarkers can be interrogated in real‐time within 1 week of tumor sampling.
  •  
8.
  • Cirenajwis, Helena, et al. (författare)
  • Reduction of the putative CD44+CD24- breast cancer stem cell population by targeting the polyamine metabolic pathway with PG11047.
  • 2010
  • Ingår i: Anti-Cancer Drugs. - 0959-4973. ; 21:10, s. 897-906
  • Tidskriftsartikel (refereegranskat)abstract
    • Cancer stem cells (CSCs) are considered to be of particular concern in cancer as they possess inherent properties of self-renewal and differentiation, along with expressing certain genes related to a mesenchymal phenotype. These features favour the promotion of tumour recurrence and metastasis in cancer patients. Thus, the optimal chemotherapeutic treatment should target the CSC population, either by killing these cells and/or by inducing their transition to a more differentiated epithelial-like phenotype. Experiments were carried out on the trastuzumab-resistant human epidermal growth factor receptor 2-overexpressing breast cancer cell line JIMT-1 to unravel the chemotherapeutic effects of the polyamine analogue [N,N]bis(ethyl)-cis-6,7-dehydrospermine (PG11047) and of the polyamine biosynthetic inhibitor 2-difluoromethylornithine (DFMO) on the CD44CD24 CSC population. Furthermore, effects on the properties of self-renewal and epithelial/mesenchymal markers were also investigated. Treatment with PG11047 reduced the CD44CD24 subpopulation of JIMT-1 cells by approximately 50%, inhibited and/or reduced self-renewal capability of the CSC population, decreased cell motility and induced expression of mesenchymal to epithelial transition-associated proteins that are involved in promoting an epithelial phenotype. By contrast, DFMO slightly increased the CD44CD24 subpopulation, increased cell motility and the level of mesenchymal-related proteins. DFMO treatment reduced the self-renewal capability of the CSC population. Both PG11047 and DFMO reduced the expression of the human epidermal growth factor receptor 2 protein, which is correlated to malignancy and resistance to trastuzumab in JIMT-1 cells. Our findings indicate that treatment with PG11047 targeted the CSC population by interfering with several stem cell-related properties, such as self-renewal, differentiation, motility and the mesenchymal phenotype.
  •  
9.
  •  
10.
  • Dahlgren, Malin, et al. (författare)
  • Preexisting Somatic Mutations of Estrogen Receptor Alpha (ESR1) in Early-Stage Primary Breast Cancer
  • 2021
  • Ingår i: JNCI Cancer Spectrum. - : Oxford University Press (OUP). - 2515-5091. ; 5:2
  • Tidskriftsartikel (refereegranskat)abstract
    • More than three-quarters of primary breast cancers are positive for estrogen receptor alpha (ER; encoded by the gene ESR1), the most important factor for directing anti-estrogenic endocrine therapy (ET). Recently, mutations in ESR1 were identified as acquired mechanisms of resistance to ET, found in 12% to 55% of metastatic breast cancers treated previously with ET. We analyzed 3217 population-based invasive primary (nonmetastatic) breast cancers (within the SCAN-B study, ClinicalTrials.gov NCT02306096), sampled from initial diagnosis prior to any treatment, for the presence of ESR1 mutations using RNA sequencing. Mutations were verified by droplet digital polymerase chain reaction on tumor and normal DNA. Patient outcomes were analyzed using Kaplan-Meier estimation and a series of 2-factor Cox regression multivariable analyses. We identified ESR1 resistance mutations in 30 tumors (0.9%), of which 29 were ER positive (1.1%). In ET-treated disease, presence of ESR1 mutation was associated with poor relapse-free survival and overall survival (2-sided log-rank test P < .001 and P = .008, respectively), with hazard ratios of 3.00 (95% confidence interval = 1.56 to 5.88) and 2.51 (95% confidence interval = 1.24 to 5.07), respectively, which remained statistically significant when adjusted for other prognostic factors. These population-based results indicate that ESR1 mutations at diagnosis of primary breast cancer occur in about 1% of women and identify for the first time in the adjuvant setting that such preexisting mutations are associated to eventual resistance to standard hormone therapy. If replicated, tumor ESR1 screening should be considered in ER-positive primary breast cancer, and for patients with mutated disease, ER degraders such as fulvestrant or other therapeutic options may be considered as more appropriate.
  •  
11.
  • Dihge, Looket, et al. (författare)
  • Prediction of lymph node metastasis in breast cancer by gene expression and clinicopathological models: Development and validation within a population based cohort.
  • 2019
  • Ingår i: Clinical Cancer Research. - 1078-0432. ; 25:21, s. 6368-6381
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: More than 70% of patients with breast cancer present with node-negative disease, yet all undergo surgical axillary staging. We aimed to define predictors of nodal metastasis using clinicopathological characteristics (CLINICAL), gene expression data (GEX), and mixed features (MIXED) and to identify patients at low risk of metastasis who might be spared sentinel lymph node biopsy (SLNB).Experimental Design: Breast tumors (n = 3,023) from the population-based Sweden Cancerome Analysis Network–Breast initiative were profiled by RNA sequencing and linked to clinicopathologic characteristics. Seven machine-learning models present the discriminative ability of N0/N+ in development (n = 2,278) and independent validation cohorts (n = 745) stratified as ER+HER2−, HER2+, and TNBC. Possible SLNB reduction rates are proposed by applying CLINICAL and MIXED predictors.Results: In the validation cohort, the MIXED predictor showed the highest area under ROC curves to assess nodal metastasis; AUC = 0.72. For the subgroups, the AUCs for MIXED, CLINICAL, and GEX predictors ranged from 0.66 to 0.72, 0.65 to 0.73, and 0.58 to 0.67, respectively. Enriched proliferation metagene and luminal B features were noticed in node-positive ER+HER2− and HER2+ tumors, while upregulated basal-like features were observed in node-negative TNBC tumors. The SLNB reduction rates in patients with ER+HER2− tumors were 6% to 7% higher for the MIXED predictor compared with the CLINICAL predictor accepting false negative rates of 5% to 10%.Conclusions: Although CLINICAL and MIXED predictors of nodal metastasis had comparable accuracy, the MIXED predictor identified more node-negative patients. This translational approach holds promise for development of classifiers to reduce the rates of SLNB for patients at low risk of nodal involvement.
  •  
12.
  • Ehinger, Anna, et al. (författare)
  • Myoepithelium assessment with p63 immunostaining in formalinfixed paraffin-embedded breast cancer tissue pre-treated with RNA-later
  • 2017
  • Ingår i: Virchows Archiv. - : Springer Science and Business Media LLC. - 1432-2307 .- 0945-6317. ; 471:Supplement 1, s. 299-299
  • Konferensbidrag (refereegranskat)abstract
    • Objective: To assessmyoepithelium with p63 in fresh breast cancer (BC)tissue samples collected in RNA later for further analysis with NextGeneration Sequencing (NGS) technique. For a better understanding ofthe NGS bulk-analysis, a central part of the sample in RNA-later isformalin-fixed paraffin-embedded to score relative cellularity in % onhematoxylin-eosin (HE) staining (% of invasive cancer, cancer in situ,benign epithelium, lymphocytes and fat). Our aim is hence to test p63immunohistochemistry (IHC) to highlight myoepithelium and to facilitatethe evaluation of the relative cellularity on BC-tissue pre-treated withRNA-later.Method: Two-hundred and twenty-four selected samples of fresh BCtissue collected in RNA-later. A 10 mg central piece from each samplewas FFPE and assembled in a tissue-microarray (TMA) and sectioned toHE and p63 IHC.Results: All samples (n = 224) had internal control for myoepitheliumsurrounding in situ cancer or benign epithelium. p63 showed positivenuclear staining in myoepithelial cells in 92 % (206/224) of samplesand false negative p63 staining in 8 % (18/224).Conclusion: p63 IHC is assessable in samples of FFPE BC-tissue pretreatedwith RNA-later.
  •  
13.
  •  
14.
  • Glodzik, Dominik, et al. (författare)
  • Comprehensive molecular comparison of BRCA1 hypermethylated and BRCA1 mutated triple negative breast cancers
  • 2020
  • Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 11:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Homologous recombination deficiency (HRD) is a defining characteristic in BRCA-deficient breast tumors caused by genetic or epigenetic alterations in key pathway genes. We investigated the frequency of BRCA1 promoter hypermethylation in 237 triple-negative breast cancers (TNBCs) from a population-based study using reported whole genome and RNA sequencing data, complemented with analyses of genetic, epigenetic, transcriptomic and immune infiltration phenotypes. We demonstrate that BRCA1 promoter hypermethylation is twice as frequent as BRCA1 pathogenic variants in early-stage TNBC and that hypermethylated and mutated cases have similarly improved prognosis after adjuvant chemotherapy. BRCA1 hypermethylation confers an HRD, immune cell type, genome-wide DNA methylation, and transcriptional phenotype similar to TNBC tumors with BRCA1-inactivating variants, and it can be observed in matched peripheral blood of patients with tumor hypermethylation. Hypermethylation may be an early event in tumor development that progress along a common pathway with BRCA1-mutated disease, representing a promising DNA-based biomarker for early-stage TNBC.
  •  
15.
  • Gruvberger, Sofia, et al. (författare)
  • Estrogen receptor beta expression is associated with tamoxifen response in ER alpha-negative breast carcinoma
  • 2007
  • Ingår i: Clinical Cancer Research. - 1078-0432. ; 13:7, s. 1987-1994
  • Tidskriftsartikel (refereegranskat)abstract
    • PURPOSE: Endocrine therapies, such as tamoxifen, are commonly given to most patients with estrogen receptor (ERalpha)-positive breast carcinoma but are not indicated for persons with ERalpha-negative cancer. The factors responsible for response to tamoxifen in 5% to 10% of patients with ERalpha-negative tumors are not clear. The aim of the present study was to elucidate the biology and prognostic role of the second ER, ERbeta, in patients treated with adjuvant tamoxifen.EXPERIMENTAL DESIGN: We investigated ERbeta by immunohistochemistry in 353 stage II primary breast tumors from patients treated with 2 years adjuvant tamoxifen, and generated gene expression profiles for a representative subset of 88 tumors.RESULTS: ERbeta was associated with increased survival (distant disease-free survival, P = 0.01; overall survival, P = 0.22), and in particular within ERalpha-negative patients (P = 0.003; P = 0.04), but not in the ERalpha-positive subgroup (P = 0.49; P = 0.88). Lack of ERbeta conferred early relapse (hazard ratio, 14; 95% confidence interval, 1.8-106; P = 0.01) within the ERalpha-negative subgroup even after adjustment for other markers. ERalpha was an independent marker only within the ERbeta-negative tumors (hazard ratio, 0.44; 95% confidence interval, 0.21-0.89; P = 0.02). An ERbeta gene expression profile was identified and was markedly different from the ERalpha signature.CONCLUSION: Expression of ERbeta is an independent marker for favorable prognosis after adjuvant tamoxifen treatment in ERalpha-negative breast cancer patients and involves a gene expression program distinct from ERalpha. These results may be highly clinically significant, because in the United States alone, approximately 10,000 women are diagnosed annually with ERalpha-negative/ERbeta-positive breast carcinoma and may benefit from adjuvant tamoxifen.
  •  
16.
  • Hegardt, Cecilia, et al. (författare)
  • Changes in polyamine metabolism during glucocorticoid-induced programmed cell death in mouse thymus
  • 2000
  • Ingår i: Cell Biology International. - : Wiley. - 1095-8355 .- 1065-6995. ; 24:12, s. 871-880
  • Tidskriftsartikel (refereegranskat)abstract
    • When mice are injected with dexamethasone, cortical thymocytes are deleted through programmed cell death (PCD). We have used this in vivo model system to investigate the kinetics of PCD and cell proliferation in relation to polyamine metabolism for 16 h after injection of dexamethasone. As a marker for PCD, we used the appearance of a sub-G(1)peak in the DNA histogram. When a sub-G(1)peak appeared at 4 h after dexamethasone treatment, the activity of the polyamine catabolic enzyme spermidine/spermine N(1)-acetyltransferase (SSAT) was significantly increased and the activity of the polyamine biosynthetic enzyme S-adenosylmethionine decarboxylase (AdoMetDC) was significantly decreased compared to the activities found in the thymi of control mice. Despite the significant changes in the activities of SSAT and AdoMetDC, the only change in the polyamine pool during the experimental period was that of putrescine. Presumably the complexity of this in vivo system masks changes in the spermidine and spermine pools that were expected in relation to the increased SSAT activity and decreased AdoMetDC activity.
  •  
17.
  • Hegardt, Cecilia, et al. (författare)
  • Different roles of spermine in glucocorticoid- and Fas-induced apoptosis
  • 2001
  • Ingår i: Experimental Cell Research. - : Elsevier BV. - 1090-2422 .- 0014-4827. ; 266:2, s. 333-341
  • Tidskriftsartikel (refereegranskat)abstract
    • Two experimental systems representative of the mitochondrial and death receptor apoptotic pathways are the dexamethasone-induced programmed cell death in mouse thymocytes and the antibody-mediated cross-ligation of the Fas receptor in the human leukemic T-cell line Jurkat, respectively. In both cell systems, caspase-9, -8, and -3 were activated upon induction of apoptosis and a sub-G(1) peak appeared as a sign of ongoing DNA fragmentation. Addition of 1 mM spermine together with dexamethasone inhibited caspase activation and the appearance of the sub-G(1) peak in mouse thymocytes. In contrast, Fas-induced cell death was totally unaffected by spermine addition. Spermine addition significantly elevated the spermine concentration in both thymocytes and Jurkat cells. Thus, spermine per se did not inhibit the caspases but rather their activation. The fact that spermine inhibited caspase activation only in the thymocytes implies that spermine inhibited dexamethasone-induced apoptosis upstream of caspase-9 activation.
  •  
18.
  • Hegardt, Cecilia (författare)
  • On the Role of Polyamines in Apoptosis
  • 2001
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Apoptosis is a kind of death that is best described as cellular suicide and it is important for normal tissue homeostasis. The process can be induced by a number of different stimuli and the dying cell goes through a defined pathway terminating in typical biochemical and morphological alterations of the cell. With my studies I wanted to investigate the role of the polyamines in the regulation of apoptosis. When inducing apoptosis in mouse thymus in vivo by treatment with the glucocorticoid dexamethasone, the activity of the polyamine biosynthetic enzyme S-adenosylmethionine decarboxylase decreased and the activity of the rate-limiting catabolic enzyme spermidine/spermine N1-acetyltransferase (SSAT) was increased. A reduction in polyamine levels was only evident though several hours after the first signs of apoptosis. A decrease in the polyamine levels was also observed in dexamethasone-induced apoptosis in mouse thymocytes in vitro and in Fas-induced apoptosis of human leukaemic T cells. Exogenous addition of 1 mM spermine inhibited apoptosis induced by dexamethasone in primary cultures of mouse thymocytes. Spermine prevented DNA fragmentation as well as the activation of caspase-9, -8 and –3. The total inhibition of caspase-9 activity was due to the spermine-mediated inhibition of cytochrome c release from the mitochondria into the cytosol. When treating the human breast cancer cell line L56Br-C1 with the spermine analogue N1, N11-diethylnorspermine, SSAT activity was induced leading to an almost total depletion of the natural polyamines. The majority of the cells died within 48 hours. This rapid cell death was shown to be apoptotic with activation of caspases and fragmentation of the DNA. In conclusion, a decrease of intra-cellular levels of polyamines seems to be important for the progression of the apoptotic process and the addition of spermine protected mouse thymocytes from apoptosis induced by dexamethasone.
  •  
19.
  • Hegardt, Cecilia, et al. (författare)
  • Rapid caspase-dependent cell death in cultured human breast cancer cells induced by the polyamine analogue N-1,N-11-diethylnorspermine
  • 2002
  • Ingår i: European Journal of Biochemistry. - : Wiley. - 0014-2956. ; 269:3, s. 1033-1039
  • Tidskriftsartikel (refereegranskat)abstract
    • The spen-nine analogue N-1,N-11-diethylnorspermine (DENSPM) efficiently depletes the cellular pools of putrescine, spermidine and spermine by down-regulating the activity of the polyamine biosynthetic enzymes and up-regulating the activity of the catabolic enzyme spermidine/spermine N-1-acetyltransferase (SSAT). In the breast cancer cell line L56Br-Cl. treatment with 10 muM DENSPM induced SSAT activity 60 and 240-fold at 24 and 48 h after seeding. respectively, which resulted in polyamine depletion. Cell proliferation appeared to be totally inhibited and within 48 h of treatment, there was an extensive apoptotic response. Fifty percent of the cells were found in the sub-G(1) region, as determined by flow cytometry, and the presence of apoptotic nuclei was morphologically assessed by fluorescence microscopy. Caspase-3 and caspase-9 activities were significantly elevated 24 h after seeding, At 48 h after seeding, caspase-3 and caspase-9 activities were further elevated and at this time point a significant activation of caspase-8 was also found. The DENSPM-induced cell death was dependent on the activation of the caspases as it was inhibited by the general caspase inhibitor Z-Val-Ala-Asp fluoromethyl ketone. The results are discussed in the fight of the L56Br-Cl cells containing mutated BRCA1 and p53, two genes involved in DNA repair.
  •  
20.
  • Hegardt, Cecilia, et al. (författare)
  • Spermine prevents cytochrome c release in glucocorticoid-induced apoptosis in mouse thymocytes.
  • 2003
  • Ingår i: Cell Biology International. - 1095-8355. ; 27:2, s. 115-121
  • Tidskriftsartikel (refereegranskat)abstract
    • Apoptosis can be induced in primary cultures of mouse thymocytes using the glucocorticoid dexamethasone. Addition of the polyamine spermine simultaneously with dexamethasone reduces the induction of apoptosis compared to treatment with dexamethasone alone. We investigated the signal transduction pathway at the mitochondrial level in order to elucidate spermine's protective effect. Mitochondrial involvement is evident due to the loss of mitochondrial transmembrane potential, release of cytochrome c into the cytosol and activation of caspase-9 in dexamethasone-treated thymocytes. The addition of spermine inhibited the release of cytochrome c from the mitochondria into the cytosol, and also the activation of caspase-9. When the mitogen concanavalin A (Con A) was added to dexamethasone- plus spermine-treated thymocytes, the number of apoptotic cells in the pre-G1peak was reduced compared to thymocytes treated with only dexamethasone plus spermine. Comparing concanavalin A added to dexamethasone-treated or to dexamethasone plus spermine-treated thymocytes, showed a markedly reduced pre-G1peak in the latter. Thus, the spermine-induced inhibition of cytochrome c release confers a survival advantage on thymocytes.
  •  
21.
  • Holm, Karolina, et al. (författare)
  • Characterisation of amplification patterns and target genes at chromosome 11q13 in CCND1-amplified sporadic and familial breast tumours.
  • 2012
  • Ingår i: Breast Cancer Research and Treatment. - : Springer Science and Business Media LLC. - 1573-7217 .- 0167-6806. ; 133:2, s. 583-594
  • Tidskriftsartikel (refereegranskat)abstract
    • Amplification of chromosomal region 11q13, containing the cell cycle regulatory gene CCND1, is frequently found in breast cancer and other malignancies. It is associated with the favourable oestrogen receptor (ER)-positive breast tumour phenotype, but also with poor prognosis and treatment failure. 11q13 spans almost 14 Mb and contains more than 200 genes and is affected by various patterns of copy number gains, suggesting complex mechanisms and selective pressure during tumour progression. In this study, we used 32 k tiling BAC array CGH to analyse 94 CCND1-amplified breast tumours from sporadic, hereditary, and familial breast cancers to fine map chromosome 11q13. A set containing 281 CCND1-non-amplified breast tumours was used for comparisons. We used gene expression data to further validate the functional effect of gene amplification. We identified six core regions covering 11q13.1-q14.1 that were amplified in different combinations. The major core contained CCND1, whereas two cores were found proximal of CCND1 and three distal. The majority of the CCND1-amplified tumours were ER-positive and classified as luminal B. Furthermore, we found that CCND1 amplification is associated with a more aggressive phenotype within histological grade 2 tumours and luminal A subtype tumours. Amplification was equally prevalent in familial and sporadic tumours, but strikingly rare in BRCA1- and BRCA2-mutated tumours. We conclude that 11q13 includes many potential target genes in addition to CCND1.
  •  
22.
  • Holm, Karolina, et al. (författare)
  • Global H3K27 trimethylation and EZH2 abundance in breast tumor subtypes
  • 2012
  • Ingår i: Molecular Oncology. - : Elsevier. - 1574-7891 .- 1878-0261. ; 6:5, s. 494-506
  • Tidskriftsartikel (refereegranskat)abstract
    • Polycomb repressive complex 2 (PRC2) and its core member enhancer of zeste homolog 2 (EZH2) mediate the epigenetic gene silencing mark: trimethylation of lysine 27 on histone 3 (H3K27me3). H3K27me3 is characteristic of the chromatin at genes involved in developmental regulation in undifferentiated cells. Overexpression of EZH2 has been found in several cancer types such as breast, prostate, melanoma and bladder cancer. Moreover, overexpression is associated with highly proliferative and aggressive types of breast and prostate tumors. We have analyzed the abundance of EZH2 and H3K27me3 using immunohistochemistry in two large and Well-characterized breast tumor data sets encompassing more than 400 tumors. The results have been analyzed in relation to the molecular subtypes of breast tumors (basal-like, luminal A, luminal B, HER2-enriched and normal-like), as well as in subtypes defined by clinical markers (triple negative, ER+/HER2-/Ki67low, ER+/HER2-/Ki67high and HER2+), and were validated in representative breast cancer cell lines by western blot. We found significantly different expression of both EZH2 and H3K27me3 across all subtypes with high abundance of EZH2 in basal-like, triple negative and HER2-enriched tumors, and high H3K27me3 in luminal A, HER2-enriched and normal-like tumors. Intriguingly, the two markers show an inverse correlation, particularly for the basal-like and triple negative tumors. Consequently, high expression of EZH2 was associated with poor distant disease-free survival whereas high expression of H3K27me3 was associated with better survival. Additionally, none of 182 breast tumors was found to carry a previously described EZH2 mutation affecting Tyr641. Our observation that increased expression of EZH2 does not necessarily correlate with increased abundance of H3K27me3 supports the idea that EZH2 can have effects beyond epigenetic silencing of target genes in breast cancer.
  •  
23.
  • Holm, Karolina, et al. (författare)
  • Molecular subtypes of breast cancer are associated with characteristic DNA methylation patterns
  • 2010
  • Ingår i: Breast Cancer Research. - : Springer Science and Business Media LLC. - 1465-5411 .- 1465-542X. ; 12:3
  • Tidskriftsartikel (refereegranskat)abstract
    • Introduction: Five different molecular subtypes of breast cancer have been identified through gene expression profiling. Each subtype has a characteristic expression pattern suggested to partly depend on cellular origin. We aimed to investigate whether the molecular subtypes also display distinct methylation profiles. Methods: We analysed methylation status of 807 cancer-related genes in 189 fresh frozen primary breast tumours and four normal breast tissue samples using an array-based methylation assay. Results: Unsupervised analysis revealed three groups of breast cancer with characteristic methylation patterns. The three groups were associated with the luminal A, luminal B and basal-like molecular subtypes of breast cancer, respectively, whereas cancers of the HER2-enriched and normal-like subtypes were distributed among the three groups. The methylation frequencies were significantly different between subtypes, with luminal B and basal-like tumours being most and least frequently methylated, respectively. Moreover, targets of the polycomb repressor complex in breast cancer and embryonic stem cells were more methylated in luminal B tumours than in other tumours. BRCA2-mutated tumours had a particularly high degree of methylation. Finally, by utilizing gene expression data, we observed that a large fraction of genes reported as having subtype-specific expression patterns might be regulated through methylation. Conclusions: We have found that breast cancers of the basal-like, luminal A and luminal B molecular subtypes harbour specific methylation profiles. Our results suggest that methylation may play an important role in the development of breast cancers.
  •  
24.
  • Holst, Martina, et al. (författare)
  • Molecular mechanisms underlying N1, N11-diethylnorspermine-induced apoptosis in a human breast cancer cell line.
  • 2008
  • Ingår i: Anti-Cancer Drugs. - 0959-4973. ; 19:9, s. 871-883
  • Tidskriftsartikel (refereegranskat)abstract
    • Polyamine analogue treatment results in growth inhibition and sometimes in cell death. Therefore, polyamine analogues are considered in the treatment of cancer; however, the cellular properties that govern sensitivity are not known. The objective of this study was to elucidate molecular mechanisms behind apoptosis induced by the polyamine analogue N, N-diethylnorspermine (DENSPM). Four different breast cancer cell lines were treated with DENSPM. Cell death was evaluated with flow cytometry and a caspase 3 assay. The levels of a number of proapoptotic and antiapoptotic proteins in subcellular compartments were evaluated with western blot. In the most sensitive cell line, DENSPM treatment induced the release of cytochrome c from mitochondria, resulting in activation of caspase 3 but without decreasing the mitochondrial transmembrane potential. However, in the three other cell lines DENSPM treatment did not induce extensive cell death. This is partly explained by the high levels of antiapoptotic proteins Bcl-2 and Bad and low levels of proapoptotic proteins Bax and procaspase 3 in these three cell lines. The results are also partly explained by the degree of activation of the catabolic enzyme spermidine/spermine-N-acetyltransferase and polyamine pool reduction achieved by DENSPM treatment. Our results show that the protein profile of proapoptotic and antiapoptotic proteins may contribute to the outcome to treatment with the polyamine analogue DENSPM. The results also indicate that it should be possible to find molecular markers for sensitivity to DENSPM that could be used in the clinic to predict sensitivity to a polyamine analogue.
  •  
25.
  • Honeth, Gabriella, et al. (författare)
  • The CD44(+)/CD24(-) phenotype is enriched in basal-like breast tumors
  • 2008
  • Ingår i: Breast Cancer Research. - : Springer Science and Business Media LLC. - 1465-5411 .- 1465-542X. ; 10:3
  • Tidskriftsartikel (refereegranskat)abstract
    • Introduction Human breast tumors are heterogeneous and consist of phenotypically diverse cells. Breast cancer cells with a CD44(+)/CD24(-) phenotype have been suggested to have tumor-initiating properties with stem cell-like and invasive features, although it is unclear whether their presence within a tumor has clinical implications. There is also a large heterogeneity between tumors, illustrated by reproducible stratification into various subtypes based on gene expression profiles or histopathological features. We have explored the prevalence of cells with different CD44/CD24 phenotypes within breast cancer subtypes. Methods Double-staining immunohistochemistry was used to quantify CD44 and CD24 expression in 240 human breast tumors for which information on other tumor markers and clinical characteristics was available. Gene expression data were also accessible for a cohort of the material. Results A considerable heterogeneity in CD44 and CD24 expression was seen both between and within tumors. A complete lack of both proteins was evident in 35% of the tumors, while 13% contained cells of more than one of the CD44(+)/CD24(-), CD44(-)/CD24(+) and CD44(+)/CD24(+) phenotypes. CD44(+)/CD24(-) cells were detected in 31% of the tumors, ranging in proportion from only a few to close to 100% of tumor cells. The CD44(+)/CD24(-) phenotype was most common in the basal-like subgroup-characterized as negative for the estrogen and progesterone receptors as well as for HER2, and as positive for cytokeratin 5/14 and/or epidermal growth factor receptor, and particularly common in BRCA1 hereditary tumors, of which 94% contained CD44(+)/CD24(-) cells. The CD44(+)/CD24(-) phenotype was surprisingly scarce in HER2+ tumors, which had a predominantly CD24(+) status. A CD44(+)/CD24(-) gene expression signature was generated, which included CD44 and alpha(6)-integrin (CD49f) among the top-ranked overexpressed genes. Conclusion We demonstrate an association between basal-like and particularly BRCA1 hereditary breast cancer and the presence of CD44(+)/CD24(-) cells. Not all basal-like tumors and very few HER2+ tumors, however, contain CD44(+)/CD24(-) cells, emphasizing that a putative tumorigenic ability may not be confined to cells of this phenotype and that other breast cancer stem cell markers remain to be identified.
  •  
26.
  • Huang, Xiaoli, et al. (författare)
  • Breast cancer stem cell selectivity of synthetic nanomolar-active salinomycin analogs.
  • 2016
  • Ingår i: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 16:1
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Cancer stem cells (CSCs) have been invoked in resistance, recurrence and metastasis of cancer. Consequently, curative cancer treatments may be contingent on CSC selective approaches. Of particular interest in this respect is the ionophore salinomycin, a natural product shown to be 100-fold more active against CSCs than clinically used paclitaxel. We have previously reported that synthetic salinomycin derivatives display increased activity against breast cancer cell lines. Herein we specifically investigate the CSC selectivity of the most active member in each class of C20-O-acylated analogs as well as a C1-methyl ester analog incapable of charge-neutral metal ion transport. METHODS: JIMT-1 breast cancer cells were treated with three C20-O-acylated analogs, the C1-methyl ester of salinomycin, and salinomycin. The effects of treatment on the CSC-related CD44(+)/CD24(-) and the aldehyde dehydrogenase positive (ALDH(+)) populations were determined using flow cytometry. The survival ability of CSCs after treatment was investigated with a colony formation assay under serum free conditions. The effect of the compounds on cell migration was evaluated using wound-healing and Boyden chamber assays. The expression of vimentin, related to mesenchymal traits and expression of E-cadherin and β-catenin, related to the epithelial traits, were investigated using immunofluorescence microscopy. RESULTS: Treatment with each of the three C20-acylated analogs efficiently decreased the putative CSC population as reflected by reduction of the CD44(+)/CD24(-) and ALDH(+) populations already at a 50 nM concentration. In addition, colony forming efficiency and cell migration were reduced, and the expression of the epithelial markers E-cadherin and β-catenin at the cell surface were increased. In contrast, salinomycin used at the same concentration did not significantly influence the CSC population and the C1-methyl ester was inactive even at a 20 μM concentration. CONCLUSIONS: Synthetic structural analogs of salinomycin, previously shown to exhibit increased activity against cancer cells, also exhibited improved activity against CSCs across several assays even at nanomolar concentrations where salinomycin was found inactive. The methyl ester analog of salinomycin, incapable of charge-neutral metal ion transport, did not show activity in CSC assays, lending experimental support to ionophoric stress as the molecular initiating event for the CSC effects of salinomycin and related structures.
  •  
27.
  • Huang, Xiaoli, et al. (författare)
  • Semisynthesis of SY-1 for Investigation of Breast Cancer Stem Cell Selectivity of C-Ring-Modified Salinomycin Analogues.
  • 2014
  • Ingår i: ACS Chemical Biology. - : American Chemical Society (ACS). - 1554-8937 .- 1554-8929. ; 9:7, s. 1587-1594
  • Tidskriftsartikel (refereegranskat)abstract
    • Salinomycin, a naturally occurring polyether ionophore was recently found to selectively reduce the proportion of CD44(+)/CD24(-) cells, a phenotype associated with breast cancer stem cells. Subsequent studies from our group showed that chemical modification of the allylic C20 hydroxyl of salinomycin, located at the C-ring, can enhance the activity of derivatives against breast cancer cells over 5-fold compared to the native structure. Access to C-ring-modified salinomycin analogues is thus of interest from both a mechanistic and a synthetic perspective. Here, we report efficient strategies for gram scale synthesis of the natural product SY-1 (20-deoxy salinomycin), and a saturated analogue, 18,19-dihydro SY-1, for a comparative in vitro investigation of the biological profiles of these compounds with that of salinomycin. Across several assays, the deoxygenated structures required higher concentrations to elicit similar cellular responses to that of salinomycin. Similarly to salinomycin, SY-1 or 18,19-dihydro SY-1 treatment was found to reduce the proportion of CD44(+)/CD24(-) cells with essentially complete selectivity up to ∼IC25. Importantly, the proportion of CD44(+)/CD24(-) cells showed a pronounced U-shaped dose response curve for salinomycin and its derivatives, but not for paclitaxel. The concentration for maximum response in this assay followed differences in IC50 for salinomycin and its analogues, which emphasizes the importance of taking concentration dependence into account when comparing effects on the CD44(+)/CD24(-) phenotype. Small differences in the global conformation within the triad of compounds investigated together with differences in activity across assays emphasize the importance of substitution at C20 for the activity of salinomycin and its derivatives.
  •  
28.
  • Huang, Xiaoli, et al. (författare)
  • The Molecular Basis for Inhibition of Stemlike Cancer Cells by Salinomycin
  • 2018
  • Ingår i: ACS Central Science. - : American Chemical Society (ACS). - 2374-7943 .- 2374-7951. ; 4:6, s. 760-767
  • Tidskriftsartikel (refereegranskat)abstract
    • Tumors are phenotypically heterogeneous and include subpopulations of cancer cells with stemlike properties. The natural product salinomycin, a K+-selective ionophore, was recently found to exert selectivity against such cancer stem cells. This selective effect is thought to be due to inhibition of the Wnt signaling pathway, but the mechanistic basis remains unclear. Here, we develop a functionally competent fluorescent conjugate of salinomycin to investigate the molecular mechanism of this compound. By subcellular imaging, we demonstrate a rapid cellular uptake of the conjugate and accumulation in the endoplasmic reticulum (ER). This localization is connected to induction of Ca2+ release from the ER into the cytosol. Depletion of Ca2+ from the ER induces the unfolded protein response as shown by global mRNA analysis and Western blot analysis of proteins in the pathway. In particular, salinomycin-induced ER Ca2+ depletion up-regulates C/EBP homologous protein (CHOP), which inhibits Wnt signaling by down-regulating β-catenin. The increased cytosolic Ca2+ also activates protein kinase C, which has been shown to inhibit Wnt signaling. These results reveal that salinomycin acts in the ER membrane of breast cancer cells to cause enhanced Ca2+ release into the cytosol, presumably by mediating a counter-flux of K+ ions. The clarified mechanistic picture highlights the importance of ion fluxes in the ER as an entry to inducing phenotypic effects and should facilitate rational development of cancer treatments.
  •  
29.
  • Janicke, Birgit, et al. (författare)
  • The antiproliferative effect of dietary fibre phenolic compounds ferulic acid and p-coumaric acid on the cell cycle in Caco-2 cells
  • 2011
  • Ingår i: Nutrition and Cancer. - : Informa UK Limited. - 1532-7914 .- 0163-5581. ; 63, s. 611-622
  • Tidskriftsartikel (refereegranskat)abstract
    • Epidemiological and animal studies have shown that dietary fiber is protective against the development of colon cancer. Dietary fiber is a rich source of the hydroxycinnamic acids ferulic acid (FA) and p-coumaric acid (p-CA), which both may contribute to the protective effect. We have investigated the effects of FA and p-CA treatment on global gene expression in Caco-2 colon cancer cells. The Caco-2 cells were treated with 150 μM FA or p-CA for 24 h, and gene expression was analyzed with cDNA microarray technique. A total of 517 genes were significantly affected by FA and 901 by p-CA. As we previously have found that FA or p-CA treatment delayed cell cycle progression, we focused on genes involved in proliferation and cell cycle regulation. The expressions of a number of genes involved in centrosome assembly, such as RABGAP1 and CEP2, were upregulated by FA treatment as well as the gene for the S phase checkpoint protein SMC1L1. p-CA treatment upregulated CDKN1A expression and downregulated CCNA2, CCNB1, MYC, and ODC1. Some proteins corresponding to the affected genes were also studied. Taken together, the changes found can partly explain the effects of FA or p-CA treatment on cell cycle progression, specifically in the S phase by FA and G(2)/M phase by p-CA treatment.
  •  
30.
  • Johansson, Veronica, et al. (författare)
  • Effect of polyamine deficiency on proteins involved in Okazaki fragment maturation.
  • 2008
  • Ingår i: Cell Biology International. - : Wiley. - 1095-8355 .- 1065-6995. ; 32, s. 1467-1477
  • Tidskriftsartikel (refereegranskat)abstract
    • Polyamine depletion causes S phase prolongation, and earlier studies indicate that the elongation step of DNA replication is affected. This led us to investigate the effects of polyamine depletion on enzymes crucial for Okazaki fragment maturation in the two breast cancer cell lines MCF-7 and L56Br-C1. In MCF-7 cells, treatment with N(1),N(11)-diethylnorspermine (DENSPM) causes S phase prolongation. In L56Br-C1 cells the prolongation is followed by massive apoptosis. In the present study we show that L56Br-C1 cells have substantially lower basal expressions of two Okazaki fragment maturation key proteins, DNA ligase I and FEN1, than MCF-7 cells. Thus, these two proteins might be promising markers for prediction of polyamine depletion sensitivity, something that can be useful for cancer treatment with polyamine analogues. DENSPM treatment affects the cellular distribution of FEN1 in L56Br-C1 cells, but not in MCF-7 cells, implying that FEN1 is affected by or involved in DENSPM-induced apoptosis.
  •  
31.
  • Jönsson, Göran B, et al. (författare)
  • Genomic subtypes of breast cancer identified by array-comparative genomic hybridization display distinct molecular and clinical characteristics
  • 2010
  • Ingår i: Breast Cancer Research. - : Springer Science and Business Media LLC. - 1465-5411 .- 1465-542X. ; 12:3
  • Tidskriftsartikel (refereegranskat)abstract
    • Introduction: Breast cancer is a profoundly heterogeneous disease with respect to biologic and clinical behavior. Gene-expression profiling has been used to dissect this complexity and to stratify tumors into intrinsic gene-expression subtypes, associated with distinct biology, patient outcome, and genomic alterations. Additionally, breast tumors occurring in individuals with germline BRCA1 or BRCA2 mutations typically fall into distinct subtypes. Methods: We applied global DNA copy number and gene-expression profiling in 359 breast tumors. All tumors were classified according to intrinsic gene-expression subtypes and included cases from genetically predisposed women. The Genomic Identification of Significant Targets in Cancer (GISTIC) algorithm was used to identify significant DNA copy-number aberrations and genomic subgroups of breast cancer. Results: We identified 31 genomic regions that were highly amplified in > 1% of the 359 breast tumors. Several amplicons were found to co-occur, the 8p12 and 11q13.3 regions being the most frequent combination besides amplicons on the same chromosomal arm. Unsupervised hierarchical clustering with 133 significant GISTIC regions revealed six genomic subtypes, termed 17q12, basal-complex, luminal-simple, luminal-complex, amplifier, and mixed subtypes. Four of them had striking similarity to intrinsic gene-expression subtypes and showed associations to conventional tumor biomarkers and clinical outcome. However, luminal A-classified tumors were distributed in two main genomic subtypes, luminal-simple and luminal-complex, the former group having a better prognosis, whereas the latter group included also luminal B and the majority of BRCA2-mutated tumors. The basal-complex subtype displayed extensive genomic homogeneity and harbored the majority of BRCA1-mutated tumors. The 17q12 subtype comprised mostly HER2-amplified and HER2-enriched subtype tumors and had the worst prognosis. The amplifier and mixed subtypes contained tumors from all gene-expression subtypes, the former being enriched for 8p12-amplified cases, whereas the mixed subtype included many tumors with predominantly DNA copy-number losses and poor prognosis. Conclusions: Global DNA copy-number analysis integrated with gene-expression data can be used to dissect the complexity of breast cancer. This revealed six genomic subtypes with different clinical behavior and a striking concordance to the intrinsic subtypes. These genomic subtypes may prove useful for understanding the mechanisms of tumor development and for prognostic and treatment prediction purposes.
  •  
32.
  • Jönsson, Göran B, et al. (författare)
  • The retinoblastoma gene undergoes rearrangements in BRCA1-deficient basal-like breast cancer.
  • 2012
  • Ingår i: Cancer Research. - 1538-7445. ; 72:16, s. 4028-4036
  • Tidskriftsartikel (refereegranskat)abstract
    • Breast tumors from BRCA1 germ line mutation carriers typically exhibit features of the basal-like molecular subtype. However, the specific genes recurrently mutated as a consequence of BRCA1 dysfunction have not been fully elucidated. In this study, we utilized gene expression profiling to molecularly subtype 577 breast tumors, including 72 breast tumors from BRCA1/2 mutation carriers. Focusing on the RB1 locus, we analyzed 33 BRCA1-mutated, 36 BRCA2-mutated and 48 non-BRCA1/2-mutated breast tumors using a custom-designed high-density oligomicroarray covering the RB1 gene. We found a strong association between the basal-like subtype and BRCA1-mutated breast tumors and the luminal B subtype and BRCA2-mutated breast tumors. RB1 was identified as a major target for genomic disruption in tumors arising in BRCA1 mutation carriers and in sporadic tumors with BRCA1 promoter-methylation, but rarely in other breast cancers. Homozygous deletions, intragenic breaks, or microdeletions were found in 33% of BRCA1-mutant tumors, 36% of BRCA1 promoter-methylated basal-like tumors, 13% of non-BRCA1 deficient basal-like tumors, and 3% of BRCA2-mutated tumors. In conclusion, RB1 was frequently inactivated by gross gene disruption in BRCA1-related hereditary breast cancer and BRCA1-methylated sporadic basal-like breast cancer, but rarely in BRCA2-hereditary breast cancer and non-BRCA1-deficient sporadic breast cancers. Together, our findings demonstrate the existence of genetic heterogeneity within the basal-like breast cancer subtype that is based upon BRCA1-status.
  •  
33.
  • Larsson, Christer, et al. (författare)
  • Prognostic implications of the expression levels of different immunoglobulin heavy chain-encoding RNAs in early breast cancer
  • 2020
  • Ingår i: npj Breast Cancer. - : Springer Science and Business Media LLC. - 2374-4677. ; 6:1
  • Tidskriftsartikel (refereegranskat)abstract
    • The extent and composition of the immune response in a breast cancer is one important prognostic factor for the disease. The aim of the current work was to refine the analysis of the humoral component of an immune response in breast tumors by quantifying mRNA expression of different immunoglobulin classes and study their association with prognosis. We used RNA-Seq data from two local population-based breast cancer cohorts to determine the expression of IGJ and immunoglobulin heavy (IGH) chain-encoding RNAs. The association with prognosis was investigated and public data sets were used to corroborate the findings. Except for IGHE and IGHD, mRNAs encoding heavy chains were generally detected at substantial levels and correlated with other immune-related genes. High IGHG1 mRNA was associated with factors related to poor prognosis such as estrogen receptor negativity, HER2 amplification, and high grade, whereas high IGHA2 mRNA levels were primarily associated with lower age at diagnosis. High IGHA2 and IGJ mRNA levels were associated with a more favorable prognosis both in univariable and multivariable Cox models. When adjusting for other prognostic factors, high IGHG1 mRNA levels were positively associated with improved prognosis. To our knowledge, these results are the first to demonstrate that expression of individual Ig class types has prognostic implications in breast cancer.
  •  
34.
  • Loman, Niklas, et al. (författare)
  • Abstract P2-02-09: Breast cancer subtype distribution and circulating tumor DNA in response to neoadjuvant chemotherapy: Experiences from a preoperative cohort within SCAN-B
  • 2018
  • Ingår i: Cancer research. Supplement. - 1538-7445. ; 78:4
  • Konferensbidrag (refereegranskat)abstract
    • Introduction: Preoperative chemotherapy in early breast cancer increases the rate of breast preservation and provides prognostic information. In the case of residual disease, a change in subtypes may be observed. Sensitive and reproducible biomarkers predicting treatment response early during the treatment course are needed in order to better exploit the potential benefit of an individualized preoperative treatment.Material and Methods: In an ongoing prospective study within the population-based SCAN-B project (NCT02306096), patients undergoing preoperative chemotherapy for early or locally recurrent breast cancer have been treated with iv Epirubicin and Cyclophosphamide q3w x 3 in sequence with either Docetaxel q3w x 3 or Paclitaxel q1w x 9 with a preoperative intent. HER2-positive cases also received HER2-directed treatment. At baseline, patients were staged using sentinel node biopsy for clinically node-negative patients and CT scan for cytologically confirmed node-positive cases. A clinical core needle biopsy as well as tissue from the surgical specimen was collected for determination of conventional biomarkers including ER, PgR, HER2 and Ki67. Tumor biopsies for biomolecule-extraction and RNA-sequencing were taken using ultrasound guidance and collected fresh in RNAlater at baseline, after 2 treatment cycles, as well as at surgery. Blood plasma samples were collected at baseline, after one-, three-, and six- 3w treatment cycles, and post-surgery. Using RNA-sequencing data, somatic mutations were identified in the tumor biopsies and personalized analyses for circulating tumor DNA (ctDNA) were performed. A pathological complete remission (pCR) was defined as the complete disappearance of invasive breast cancer in the breast and axilla at time of definitive surgery. Subtyping was performed using modified St Gallen criteria (2013).Results: Thus far, 45 patients aged 24-74 years have been included, of which 34 (76 %) were clinical stage 2 and 11 (24%) were stage 3. The subtype distribution at baseline was five Luminal A-like (11 %), 21 Luminal B-like (HER2 negative) (47 %), 8 HER2-positive (18 %) and 11 Triple-negative (ductal) (24 %). The rates of pCR in 38 operated cases to date were 0/3 Luminal A-like, 3/19 Luminal B-like (HER2 negative), 2/8 HER2-positive, and 4/7 Triple-negative (overall 24 % pCR rate). One patient did not undergo surgery due to clinically progressive disease. In 25 cases with evaluable residual disease at surgery, there was a shift in the subtype in 13 (52 %), the majority of which represented a transition from Luminal B to Luminal A. No Triple-negative cases underwent a change in subtype during treatment. Results of the ctDNA analyses will be presented at the meeting.Discussion: We have established an infrastructure allowing for an extensive evaluation of preoperative chemotherapy in early breast cancer. The goal is to develop methods to refine response-guided treatment in early breast cancer using molecular responses in the tumor as well as in the blood circulation. The patients continue to be prospectively monitored with iterative ctDNA analyses during follow-up.
  •  
35.
  • Lundgren, Christine, et al. (författare)
  • Agreement between molecular subtyping and surrogate subtype classification : a contemporary population-based study of ER-positive/HER2-negative primary breast cancer
  • 2019
  • Ingår i: Breast Cancer Research and Treatment. - : SPRINGER. - 0167-6806 .- 1573-7217. ; 178:2, s. 459-467
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: Oestrogen receptor-positive (ER+) and human epidermal receptor 2-negative (HER2-) breast cancers are classified as Luminal A or B based on gene expression, but immunohistochemical markers are used for surrogate subtyping. The aims of this study were to examine the agreement between molecular subtyping (MS) and surrogate subtyping and to identify subgroups consisting mainly of Luminal A or B tumours.Methods: The cohort consisted of 2063 patients diagnosed between 2013-2017, with primary ER+/HER2- breast cancer, analysed by RNA sequencing. Surrogate subtyping was performed according to three algorithms (St. Gallen 2013, Maisonneuve and our proposed Grade-based classification). Agreement (%) and kappa statistics (kappa) were used as concordance measures and ROC analysis for luminal distinction. Ki67, progesterone receptor (PR) and histological grade (HG) were further investigated as surrogate markers.Results: The agreement rates between the MS and St. Gallen 2013, Maisonneuve and Grade-based classifications were 62% (kappa = 0.30), 66% (kappa = 0.35) and 70% (kappa = 0.41), respectively. PR did not contribute to distinguishing Luminal A from B tumours (auROC = 0.56). By classifying HG1-2 tumours as Luminal A-like and HG3 as Luminal B-like, agreement with MS was 80% (kappa = 0.46). Moreover, by combining HG and Ki67 status, a large subgroup of patients (51% of the cohort) having > 90% Luminal A tumours could be identified.Conclusions: Agreement between MS and surrogate classifications was generally poor. However, a post hoc analysis showed that a combination of HG and Ki67 could identify patients very likely to have Luminal A tumours according to MS.
  •  
36.
  • Malakpour Permlid, Atena, et al. (författare)
  • Identification of Extracellular Matrix Proteins Secreted by Human Dermal Fibroblasts Cultured in 3D Electrospun Scaffolds
  • 2021
  • Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 11
  • Tidskriftsartikel (refereegranskat)abstract
    • The appreciation that cell interactions in tissues is dependent on their three dimensional (3D) distribution has stimulated the development of 3D cell culture models. We constructed an artificial 3D tumour by culturing human breast cancer JIMT-1 cells and human dermal fibroblasts (HDFs) in a 3D network of electrospun polycaprolactone fibres. Here, we investigate ECM components produced by the cells in the artificial 3D tumour, which is an important step in validating the model. Immunostaining and confocal fluorescence microscopy show that the ECM proteins fibronectin, collagen I, and laminin are deposited throughout the entire 3D structure. Secreted soluble factors including matrix metalloproteinases (MMPs) and interleukine-6 (IL-6) were analysed in collected medium and were found to be mainly derived from the HDFs. Treatment with transforming growth factor-β1 (TGF-β1), a major cytokine found in a tumour, significantly alters the MMP activity and IL-6 concentration. In addition, TGF-β1 treatment, changes the morphology of the HDFs to become more elongated and with increased linearized actin filaments compared to non-treated HDFs. Collectively, these novel findings suggest that the artificial 3D tumour displays a clear cell distribution and ECM deposition that resembles a tumour environment in vivo, suggesting an innovative biological model to study a human tumour.
  •  
37.
  •  
38.
  • Mohlin, Åsa, et al. (författare)
  • Psychological resilience and health-related quality of life in Swedish women with newly diagnosed breast cancer
  • 2020
  • Ingår i: Cancer Management and Research. - 1179-1322. ; 12, s. 12041-12051
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: Psychological resilience appears to be an important influencing factor in various aspects of health-related quality of life (HRQoL) in a context of adversity, eg, being informed of a cancer diagnosis. The purpose was to investigate psychological resilience and HRQoL in Swedish women with newly diagnosed breast cancer in relation to demographic and clinicopathological characteristics. Methods: A population-based cross-sectional study was conducted including 517 women with breast cancer in the South Swedish Health Care Region. Participants were enrolled at the time of consultation for the diagnosis. Psychological resilience was assessed with the Connor-Davidson Resilience Scale 25 (CD-RISC25), and HRQoL was assessed with the Short Form Health Survey. The participants responded to questions regarding demographic variables. Clinicopathological data were collected from the Swedish National Quality Register for Breast Cancer. Results: The mean score for psychological resilience was 70.6, identifying 15% of included patients with a score lower than 58 (−1 standard deviation). The study cohort had significantly lower mean scores for several aspects of HRQoL compared with Swedish normative data. Regression analyses demonstrated that psychological resilience was significantly associated with all domains of HRQoL after adjustment for demographic and clinicopathological factors. Conclusion: Higher levels of psychological resilience were significantly related to higher levels of HRQoL in Swedish women with newly diagnosed breast cancer and no modifying factor was identified. The assessment of psychological resilience at the time of breast cancer diagnosis might allow for early identification of women in need of more intense psychosocial support. Future studies are needed to identify a clinically relevant threshold of the CD-RISC25.
  •  
39.
  • Mohlin, Åsa, et al. (författare)
  • Psychological resilience and health‐related quality of life in 418 swedish women with primary breast cancer : Results from a prospective longitudinal study
  • 2021
  • Ingår i: Cancers. - : MDPI AG. - 2072-6694. ; 13:9
  • Tidskriftsartikel (refereegranskat)abstract
    • Psychological resilience is considered a major protective psychological mechanism that enables a person to successfully handle significant adversities, e.g., a cancer diagnosis. Higher levels of resilience have been associated with higher levels of health‐related quality of life (HRQoL) in breast cancer (BC) patients, but research examining the longitudinal process of resilience is limited. The aim of this population‐based longitudinal study was to investigate resilience and HRQoL from diagnosis to one year later in 418 Swedish women with primary BC. Resilience was measured with the Connor–Davidson Resilience Scale 25, and HRQoL was measured with the Short Form Health Survey. The participants responded to questions regarding demographic and study‐specific varia-bles. Clinicopathological variables were collected from the Swedish National Quality Register for Breast Cancer. The mean score for resilience was 70.6 (standard deviation, SD = 13.0) at diagnosis and 68.9 (SD = 14.0) one year later, p < 0.001. The level of trust in the treatment and financial situation demonstrated the greatest association with the change in resilience levels. No oncological treatment modality was associated with a change in resilience levels. HRQoL decreased over time in the co-hort. Resilience was positively associated with HRQoL at one year post diagnosis, which demon-strates that resilience is an important factor in maintaining HRQoL.
  •  
40.
  • Morgan, G, et al. (författare)
  • Abstract P3-02-02: Concordance between immunohistochemical and gene-expression based subtyping of early breast cancer using core needle biopsies and surgical specimens - experices from SCAN-B
  • 2018
  • Ingår i: Cancer research. Supplement. - 1538-7445. ; 78:4
  • Konferensbidrag (refereegranskat)abstract
    • Introduction: Preoperative chemotherapy in early breast cancer increases the rate of breast preservation and provides prognostic information. Treatment decisions in these cases rely on biomarker assessments and subtyping from tissue acquired through core needle biopsies. Tumor heterogeneity and representativity are pit-falls when limited tissue is available. Biomarker expression may change considerably as a result of preoperative chemotherapy, and in a subset of cases a complete pathological response at time of surgery may even preclude any further assessment. Therefore, the reliability and reproducibility of biomarkers in base-line core biopsies are of utmost importance for patients treated with preoperative chemotherapy.Material and Methods: In an ongoing population-based study of early breast cancer, the SCAN-B (NCT02306096), patients were identified for whom an ultra-sound guided core needle biopsy was analyzed for biomarkers during primary clinical work-up and the patient was offered primary surgery as initial treatment. Clinical biomarker profiles including immunohistochemical (IHC) determinations of ER, PgR, HER2 and Ki67 were translated to subtypes according to modified St Gallen criteria (2013) and compared with paired samples from surgical specimens. In addition, tumor specimens for biomolecule extraction and RNA sequencing were collected fresh in RNAlater.Results: IHC data was available from 51 paired samples. The subtype distribution in core needle biopsies was DCIS in 1 case (2 %), LCIS in 1 case (2 %) Luminal A-like in 16 cases (31 %), Luminal B-like (HER2 negative) in 26 cases (51 %), Luminal B-HER2-like (HER2 positive) in 4 cases (8 %), HER2-positive (non-luminal) in 1 case (2 %) and triple negative (ductal) breast cancer in 2 cases (4 %). The subtype distribution in surgical specimens was DCIS in 0 case (0 %), LCIS in 1 case (2 %) Luminal A-like in 18 cases (35 %), Luminal B-like (HER2negative) in 23 cases (45 %), Luminal B--like (HER2 positive) in 6 cases (12 %), HER2-positive (non-luminal) in 1 case (2 %) and triple negative (ductal) breast cancer in 2 cases (4 %). Notably, 5/16 cases classified as Luminal A-like in the core needle biopsy were reclassified as Luminal B-like (HER2-negative) in the surgical specimen, whereas 9/26 cases classified as Luminal B-like (HER2-negative) in the core needle biopsy were reclassified as either Luminal A-like (7 cases) or Luminal B-like (HER2 positive) (2 cases) in the surgical specimen. In all instances, except one, transition between Luminal A-like and Luminal B-like was due to recorded Ki67 expression. One case that was classified as a DCIS in the core needle was reclassified as Luminal B-like (HER2 negative) at time of surgery.Discussion: In this limited material, discordance between evaluations regarding Luminal A-like and Luminal B-like was considerable. Especially the misclassification of primary HER2-positive breast cancer needs further evaluation. These findings may be caused by tumor heterogeneity, and highlight the risk of both over- and under-treatment upon biomarker assessment from core needle biopsies. Data from gene expression based subtype classifications will be presented during the meeting.
  •  
41.
  • Myhre, Louise, et al. (författare)
  • Different cell cycle kinetic effects of N1,N11-diethylnorspermine-induced polyamine depletion in four human breast cancer cell lines.
  • 2008
  • Ingår i: Anti-Cancer Drugs. - 0959-4973. ; 19:4, s. 359-368
  • Tidskriftsartikel (refereegranskat)abstract
    • Polyamine analogues are presently undergoing clinical evaluation in the treatment of cancer. To better understand under what circumstances treatment with a polyamine analogue will yield beneficial results, we have investigated the effect of N,N-diethylnorspermine (DENSPM) on cell cycle kinetics of the human breast cancer cell lines SK-BR-3, MCF-7, HCC1937, and L56Br-C1. A bromodeoxyuridine-DNA flow cytometry method was used to evaluate the treatment with 10 micromol/l DENSPM on cell cycle kinetics. A correlation between polyamine pool size after DENSPM treatment and cell cycle kinetic effects was found. The most sensitive cell cycle phase was the S phase, followed by an effect on the G2+M phase and then the G1/S transition. The levels of a number of cell cycle regulatory proteins such as cyclin E1, cyclin A2, and cyclin B1 were lowered by DENSPM treatment, which may explain the effects on cell cycle kinetics. The two cell lines that were most sensitive to DENSPM treatment belong to the basal-like subtype of breast cancer and they were deficient with respect to p53, BRCA1, and RB1.
  •  
42.
  • Olsson, Eleonor, et al. (författare)
  • CD44 isoforms are heterogeneously expressed in breast cancer and correlate with tumor subtypes and cancer stem cell markers.
  • 2011
  • Ingår i: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 11
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: The CD44 cell adhesion molecule is aberrantly expressed in many breast tumors and has been implicated in the metastatic process as well as in the putative cancer stem cell (CSC) compartment. We aimed to investigate potential associations between alternatively spliced isoforms of CD44 and CSCs as well as to various breast cancer biomarkers and molecular subtypes. METHODS: We used q-RT-PCR and exon-exon spanning assays to analyze the expression of four alternatively spliced CD44 isoforms as well as the total expression of CD44 in 187 breast tumors and 13 cell lines. ALDH1 protein expression was determined by IHC on TMA. RESULTS: Breast cancer cell lines showed a heterogeneous expression pattern of the CD44 isoforms, which shifted considerably when cells were grown as mammospheres. Tumors characterized as positive for the CD44+/CD24- phenotype by immunohistochemistry were associated to all isoforms except the CD44 standard (CD44S) isoform, which lacks all variant exons. Conversely, tumors with strong expression of the CSC marker ALDH1 had elevated expression of CD44S. A high expression of the CD44v2-v10 isoform, which retain all variant exons, was correlated to positive steroid receptor status, low proliferation and luminal A subtype. The CD44v3-v10 isoform showed similar correlations, while high expression of CD44v8-v10 was correlated to positive EGFR, negative/low HER2 status and basal-like subtype. High expression of CD44S was associated with strong HER2 staining and also a subgroup of basal-like tumors. Unsupervised hierarchical cluster analysis of CD44 isoform expression data divided tumors into four main clusters, which showed significant correlations to molecular subtypes and differences in 10-year overall survival. CONCLUSIONS: We demonstrate that individual CD44 isoforms can be associated to different breast cancer subtypes and clinical markers such as HER2, ER and PgR, which suggests involvement of CD44 splice variants in specific oncogenic signaling pathways. Efforts to link CD44 to CSCs and tumor progression should consider the expression of various CD44 isoforms.
  •  
43.
  • Rennstam, Karin, et al. (författare)
  • Numb protein expression correlates with a basal-like phenotype and cancer stem cell markers in primary breast cancer.
  • 2010
  • Ingår i: Breast Cancer Research and Treatment. - : Springer Science and Business Media LLC. - 1573-7217 .- 0167-6806. ; 122, s. 315-324
  • Tidskriftsartikel (refereegranskat)abstract
    • Decreased expression of Numb, resulting in activation of the proto-oncogene Notch1 and reduction in the tumor suppressor p53, has been demonstrated in mammary carcinomas. The aim of this study was to investigate the relationship between Numb protein expression and clinicopathological characteristics, tumor biological subtypes and putative cancer stem cell markers in a well-characterized cohort of primary human breast cancers. Immunohistochemistry was performed on tissue microarrays of primary invasive breast tumors using a polyclonal anti-Numb primary antibody. Of the 241 tumors evaluated, 50 (21%) displayed deficient or reduced Numb immunoreactivity. Retained Numb expression was significantly correlated to estrogen (ER) and progesterone receptor (PR) positivity (P < 0.001 and P = 0.004, respectively). Interestingly, we found that a higher percentage of the tumors with deficient or reduced Numb expression belonged to the triple-negative (ER-/PR-/HER2-) subgroup compared to tumors with retained Numb expression (P = 0.004). Transcriptional profiling of a subset of these tumors linked NOTCH1 and BIRC5, both downstream targets of Numb, to the triple-negative subgroup in an inverse manner. Typically, subgroups characterized by the low expression of Numb expressed higher levels of NOTCH1 and BIRC5 (encoding survivin). We also found deficient expression of Numb in a significantly higher proportion of BRCA1 dependent tumors, which are usually triple-negative, compared to sporadic tumors. The expression of Numb in 14 breast cancer cell lines correlated similarly to their respective molecular subtypes. We further established an inverse correlation between the Numb expression levels and the CD44+/CD24- cancer stem cell phenotype (P = 0.05) in primary tumors. Finally, decreased Numb expression was associated with poorer distant disease-free survival (P = 0.01). Taken together, our results indicate that loss of Numb expression is a marker of tumor aggressiveness, potentially linked to BRCA1 status and a cancer stem cell phenotype in primary breast cancer.
  •  
44.
  • Rydén, Lisa, et al. (författare)
  • Minimizing inequality in access to precision medicine in breast cancer by real-time population-based molecular analysis in the SCAN-B initiative
  • 2018
  • Ingår i: British Journal of Surgery. - : WILEY. - 0007-1323 .- 1365-2168. ; 105:2, s. E158-E168
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Selection of systemic therapy for primary breast cancer is currently based on clinical biomarkers along with stage. Novel genomic tests are continuously being introduced as more precise tools for guidance of therapy, although they are often developed for specific patient subgroups. The Sweden Cancerome Analysis Network - Breast (SCAN-B) initiative aims to include all patients with breast cancer for tumour genomic analysis, and to deliver molecular subtype and mutational data back to the treating physician.Methods: An infrastructure for collection of blood and fresh tumour tissue from all patients newly diagnosed with breast cancer was set up in 2010, initially including seven hospitals within the southern Sweden regional catchment area, which has 1.8 million inhabitants. Inclusion of patients was implemented into routine clinical care, with collection of tumour tissue at local pathology departments for transport to the central laboratory, where routines for rapid sample processing, RNA sequencing and biomarker reporting were developed.Results: More than 10 000 patients from nine hospitals have currently consented to inclusion in SCAN-B with high (90 per cent) inclusion rates from both university and secondary hospitals. Tumour samples and successful RNA sequencing arc being obtained from more than 70 per cent of patients, showing excellent representation compared with the national quality registry as a truly population-based cohort. Molecular biomarker reports can be delivered to multidisciplinary conferences within 1 week.Conclusion: Population-based collection of fresh tumour tissue is feasible given a decisive joint effort between academia and collaborative healthcare groups, and with governmental support. An infrastructure for genomic analysis and prompt data output paves the way for novel systemic therapy for patients from all hospitals, irrespective of size anti location.
  •  
45.
  •  
46.
  •  
47.
  • Saghir, Hani, et al. (författare)
  • How Reliable Are Gene Expression-Based and Immunohistochemical Biomarkers Assessed on a Core-Needle Biopsy? A Study of Paired Core-Needle Biopsies and Surgical Specimens in Early Breast Cancer
  • 2022
  • Ingår i: Cancers. - : MDPI AG. - 2072-6694. ; 14:16, s. 1-16
  • Tidskriftsartikel (refereegranskat)abstract
    • In early breast cancer, a preoperative core-needle biopsy (CNB) is vital to confirm the malignancy of suspected lesions and for assessing the expression of treatment predictive and prognostic biomarkers in the tumor to choose the optimal treatments, emphasizing the importance of obtaining reliable results when biomarker status is assessed on a CNB specimen. This study aims to determine the concordance between biomarker status assessed as part of clinical workup on a CNB compared to a medically untreated surgical specimen. Paired CNB and surgical specimens from 259 patients that were part of the SCAN-B cohort were studied. The concordance between immunohistochemical (IHC) and gene expression (GEX) based biomarker status was investigated. Biomarkers of interest included estrogen receptor (ER; specifically, the alpha variant), progesterone receptor (PgR), Ki67, HER2, and tumor molecular subtype. In general, moderate to very good correlation in biomarker status between the paired CNB and surgical specimens was observed for both IHC assessment (83–99% agreement, kappa range 0.474–0.917) and GEX assessment (70–97% agreement, kappa range 0.552–0.800), respectively. However, using IHC, 52% of cases with low Ki67 status in the CNB shifted to high Ki67 status in the surgical specimen (McNemar’s p = 0.011). Similarly, when using GEX, a significant shift from negative to positive ER (47%) and from low to high Ki67 (16%) was observed between the CNB and surgical specimen (McNemar’s p = 0.027 and p = 0.002 respectively). When comparing biomarker status between different techniques (IHC vs. GEX) performed on either CNBs or surgical specimens, the agreement in ER, PgR, and HER2 status was generally over 80% in both CNBs and surgical specimens (kappa range 0.395–0.708), but Ki67 and tumor molecular subtype showed lower concordance levels between IHC and GEX (48–62% agreement, kappa range 0.152–0.398). These results suggest that both the techniques used for collecting tissue samples and analyzing biomarker status have the potential to affect the results of biomarker assessment, potentially also impacting treatment decisions and patient survival outcomes
  •  
48.
  • Sartor, Hanna, et al. (författare)
  • “Association of mammographic features with molecular breast tumor profiles”
  • 2021
  • Ingår i: Cancer Treatment and Research Communications. - : Elsevier BV. - 2468-2942. ; 28
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: Mammographic density and tumor appearance are breast cancer prognostic factors. Conceivably, mammographic features are macroscopic reflections of tumor´s molecular composition, but to an unknown extent. Our aim was to study associations of mammographic features with molecular tumor profiles. Methods: Invasive breast cancers (2007-2016) in Malmö Diet and Cancer Study (MDCS) for which there were tumor RNA-sequencing analyses within Sweden Cancerome Analysis Network – Breast (SCAN-B) (n=102) or All Breast Cancer in Malmö (ABIM) (n=50) were identified. Density (fatty vs. dense), tumor appearance (mass vs. spiculation), and intrinsic subtypes were registered. Differences in gene/metagene expression and Microenvironment Cell Population Counter were analyzed with R. Overall survival was used as endpoint. Results: No gene expression differences between density groups was observed. In one cohort (but not the other), Luminal A tumors associated with fatty breasts. For spiculation vs. mass, (p<0.01, t-test) 86 genes were differentially expressed; only one gene was differentially expressed comparing density. Gene set enrichment analysis showed genes highly expressed in spiculated tumors were enriched for extracellular matrix-associated genes whereas genes highly expressed with masses were associated with proliferation. A spiculation metagene, based on differentially expressed genes, showed association with estrogen receptor positivity, lower grade, and improved survival, but it was not an independent prognostic factor. Conclusion: There are clear differences in molecular composition between breast tumors with a spiculated appearance vs. a mass as the dominant tumor appearance. However, there are no apparent molecular differences related to the density of the breast in which the tumor has arisen.
  •  
49.
  •  
50.
  • Staaf, Johan, et al. (författare)
  • Abstract P1-06-01: Putting multigene signatures to the test: Prognostic assessment in population-based contemporary clinical breast cancer
  • 2018
  • Ingår i: Cancer research. Supplement. - 1538-7445. ; 78:4
  • Konferensbidrag (refereegranskat)abstract
    • Background Gene expression signatures hold promise for a molecularly driven division of primary breast cancer with clinical implications. A gap still remains in the application/validation of such signatures in actual clinical treatment groups from unselected, population-based, primary breast cancer receiving current standard of care therapy. We analyzed classification proportions and overall survival (OS) of 14 reported gene expression phenotypes (GEPs) and risk predictors (RPs) in seven clinical treatments groups from an 3273-sample breast cancer cohort representative of population-based disease in the South Swedish healthcare region. Patients and methods Between 2010-09-01 to 2015-03-31, 5101 (87%) of 5892 patients with invasive primary disease in the healthcare region were included in the SCAN-B study (ClinicalTrials.gov ID: NCT02306096). Inclusion criteria included no generalized/prior contralateral disease and known surgery/treatment status (neo- or adjuvant). 3273 tumors were profiled by RNA sequencing and matched to clinicopathological patient data from the National Breast Cancer Register, with distribution of clinicopathological characteristics reflecting proportions in the catchment region. RNA profiles were classified according to 14 reported gene signatures featuring both GEPs (PAM50, IC10, CIT, TNBCtype) and specific risk predictors (e.g. Oncotype Dx, 70-gene, 76-gene, ROR-variants, genomic grade index). Classifications were investigated for association with patient OS by univariate and multivariate analyses in seven adjuvant clinical treatment groups: TNBC-ACT (adjuvant chemotherapy, n=228), TNBC-untreated (n=83), HER2+/ER- with trastuzumab + ACT treatment (n=101), HER2+/ER+ with trastuzumab + ACT + endocrine treatment (n=210), ER+/HER2- with endocrine treatment (n=1477), ER+/HER2- with endocrine + ACT treatment (n=637), and ER+/HER2- untreated (n=216). Results For the majority of signatures, analysis of classification demonstrated prognostic value limited to ER+/HER2- tumors given follow-up time. Several signatures (including Oncotype Dx, 70-gene, ROR-variants) showed strong predictive value in identifying a subset of ER+/HER2- patients receiving a combination of endocrine and ACT therapy with excellent overall survival (>96%), indicating appropriate therapy selection. In addition, for both ER+/HER2- treatment groups signature analysis identified high-risk groups of patients in clear need of additional treatment beyond standard therapeutic regimes, even with less than 5-years of follow-up. Conclusions Our results support the prognostic association of gene expression signatures in large unselected population-based primary breast cancer cohorts even with a short follow-up of OS.Importantly, prognostic associations are limited to specific subgroups for different classifiers and in population-based breast cancer some clinically important subgroups constitute a small proportion of cases. In this context, continued population-based inclusion and broad transcriptional profiling of breast cancer patients provides an opportunity for application to broader patient groups (e.g. TNBC and HER2+), and for consensus classification of individual risk assessments that could potentially provide more stable predictions.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-50 av 58
Typ av publikation
tidskriftsartikel (46)
konferensbidrag (10)
annan publikation (1)
doktorsavhandling (1)
Typ av innehåll
refereegranskat (52)
övrigt vetenskapligt/konstnärligt (6)
Författare/redaktör
Hegardt, Cecilia (58)
Borg, Åke (35)
Vallon-Christersson, ... (30)
Rydén, Lisa (29)
Loman, Niklas (27)
Larsson, Christer (25)
visa fler...
Ehinger, Anna (25)
Malmberg, Martin (23)
Saal, Lao (22)
Häkkinen, Jari (21)
Oredsson, Stina (16)
Staaf, Johan (15)
Bendahl, Pär Ola (14)
Fernö, Mårten (9)
Grabau, Dorthe (9)
Brueffer, Christian (9)
Jönsson, Göran B (9)
Ringnér, Markus (8)
Chen, Yilun (8)
Saal, Lao H. (8)
Holm, Karolina (8)
Gruvberger, Sofia (7)
Malmström, Per (6)
Manjer, Jonas (5)
Honeth, Gabriella (5)
Lövgren, Kristina (5)
Borgström, Björn (5)
Strand, Daniel (5)
Huang, Xiaoli (5)
Gladchuk, Sergii (5)
George, Anthony (5)
Hedenfalk, Ingrid (4)
Persson, Lo (4)
Lindman, Henrik (4)
Winter, Christof (4)
Arason, Adalgeir (4)
Reuterswärd, Christe ... (4)
Olsson, Håkan (3)
Malina, Janne (3)
Nik-Zainal, Serena (3)
Agnarsson, Bjarni A. (3)
Barkardottir, Rosa B ... (3)
Ehrencrona, Hans (3)
Olofsson, Helena (3)
Gunnarsson, Haukur (3)
Johannsson, Oskar TH (3)
Hallberg, Ingalill R ... (3)
Luts, Lena (3)
Glodzik, Dominik (3)
Kvist, Anders (3)
visa färre...
Lärosäte
Lunds universitet (58)
Uppsala universitet (4)
Linköpings universitet (2)
Karolinska Institutet (1)
Språk
Engelska (58)
Forskningsämne (UKÄ/SCB)
Medicin och hälsovetenskap (55)
Naturvetenskap (6)

År

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy