| 1. |
- Abdulla, Maysaa, et al.
(författare)
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Cell-of-origin determined by both gene expression profiling and immunohistochemistry is the strongest predictor of survival in patients with diffuse large B-cell lymphoma
- 2020
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Ingår i: American Journal of Hematology. - : Wiley. - 0361-8609 .- 1096-8652. ; 95:1, s. 57-67
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Tidskriftsartikel (refereegranskat)abstract
- The tumor cells in diffuse large B-cell lymphomas (DLBCL) are considered to originate from germinal center derived B-cells (GCB) or activated B-cells (ABC). Gene expression profiling (GEP) is preferably used to determine the cell of origin (COO). However, GEP is not widely applied in clinical practice and consequently, several algorithms based on immunohistochemistry (IHC) have been developed. Our aim was to evaluate the concordance of COO assignment between the Lymph2Cx GEP assay and the IHC-based Hans algorithm, to decide which model is the best survival predictor. Both GEP and IHC were performed in 359 homogenously treated Swedish and Danish DLBCL patients, in a retrospective multicenter cohort. The overall concordance between GEP and IHC algorithm was 72%; GEP classified 85% of cases assigned as GCB by IHC, as GCB, while 58% classified as non-GCB by IHC, were categorized as ABC by GEP. There were significant survival differences (overall survival and progression-free survival) if cases were classified by GEP, whereas if cases were categorized by IHC only progression-free survival differed significantly. Importantly, patients assigned as non-GCB/ABC both by IHC and GEP had the worst prognosis, which was also significant in multivariate analyses. Double expression of MYC and BCL2 was more common in ABC cases and was associated with a dismal outcome. In conclusion, to determine COO both by IHC and GEP is the strongest outcome predictor to identify DLBCL patients with the worst outcome.
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| 2. |
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| 3. |
- Andersson-Evelönn, Emma, 1983-, et al.
(författare)
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Combining epigenetic and clinicopathological variables improves specificity in prognostic prediction in clear cell renal cell carcinoma
- 2020
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Ingår i: Journal of Translational Medicine. - : Springer Science and Business Media LLC. - 1479-5876. ; 18:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Metastasized clear cell renal cell carcinoma (ccRCC) is associated with a poor prognosis. Almost one-third of patients with non-metastatic tumors at diagnosis will later progress with metastatic disease. These patients need to be identified already at diagnosis, to undertake closer follow up and/or adjuvant treatment. Today, clinicopathological variables are used to risk classify patients, but molecular biomarkers are needed to improve risk classification to identify the high-risk patients which will benefit most from modern adjuvant therapies. Interestingly, DNA methylation profiling has emerged as a promising prognostic biomarker in ccRCC. This study aimed to derive a model for prediction of tumor progression after nephrectomy in non-metastatic ccRCC by combining DNA methylation profiling with clinicopathological variables.Methods: A novel cluster analysis approach (Directed Cluster Analysis) was used to identify molecular biomarkers from genome-wide methylation array data. These novel DNA methylation biomarkers, together with previously identified CpG-site biomarkers and clinicopathological variables, were used to derive predictive classifiers for tumor progression.Results: The “triple classifier” which included both novel and previously identified DNA methylation biomarkers together with clinicopathological variables predicted tumor progression more accurately than the currently used Mayo scoring system, by increasing the specificity from 50% in Mayo to 64% in our triple classifier at 85% fixed sensitivity. The cumulative incidence of progress (pCIP5yr) was 7.5% in low-risk vs 44.7% in high-risk in M0 patients classified by the triple classifier at diagnosis.Conclusions: The triple classifier panel that combines clinicopathological variables with genome-wide methylation data has the potential to improve specificity in prognosis prediction for patients with non-metastatic ccRCC.
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| 4. |
- Andersson-Evelönn, Emma, 1983-
(författare)
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DNA methylation as a prognostic marker in clear cell Renal Cell Carcinoma
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Clear cell renal cell carcinoma (ccRCC) is the most common type of renal cell carcinoma worldwide. Metastatic ccRCC is correlated to poor prognosis whereas non-metastatic disease has a 5-year survival rate up to 90%. Due to increased accessibility to different types of diagnostic imaging the frequency of metastatic ccRCC at diagnosis has decreased since the beginning of the 21st century. This has led to an earlier detection of primary tumors before patients present symptoms. However, 20-30% of the non-metastatic patients at diagnosis will progress and metastasize within five years of primary nephrectomy. Identifying patients at high risk of tumor progression at an early stage after diagnosis is of importance to improve outcome and survival. Currently, in Sweden, the Mayo scoring system is used to divide tumors into low, intermediate or high risk for tumor progression.DNA methylation has been associated with tumor development and progression in different malignancies. In this thesis, Illumina Infinium HumanMeth27 BeadChip Arrays and Human Meth450K BeadChip Arrays have been used to evaluate the relationship between methylation and clinicopathological variables as well as ccRCC outcome in 45 and 115 patients.Our studies identified an association between higher level of promoter-associated DNA methylation and clinicopathological variables in ccRCC. There was a significant stepwise increase of average methylation from tumor-free tissue, via non-metastatic tumors to metastatic disease. Cluster analysis divided patients into two distinct groups that differed in average methylation levels, TNM stage, Fuhrman nuclear grade, tumor size, survival and tumor progression. We also presented two prognostic classifiers for non-metastatic tumors; the promoter methylation classifier (PMC) panel and the triple classifier. The PMC panel divided tumors depending on the methylation level, PMC low or PMC high, with significantly worse prognosis in the PMC high group. This data was verified in an independent, publically available cohort. The triple classifier was created using a combination of clinicopathological variables, previously identified CpGs biomarkers and a novel cluster analysis approach (Directed Cluster Analysis). The triple classifier had a higher specificity compared to the clinically used Mayo scoring system and predicted tumor progression with higher accuracy at a fixed sensitivity.The identification of two epigenetic classifiers that predicted outcome in non-metastatic ccRCC further establishes the role of DNA methylation as a prognostic marker. This knowledge can contribute to identification of patients with a high risk of tumor progression and can be of importance in the decision regarding adjuvant treatment post-nephrectomy.
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| 5. |
- Andersson Evelönn, Emma, 1983-, et al.
(författare)
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DNA methylation associates with survival in non-metastatic clear cell renal cell carcinoma
- 2019
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Ingår i: BMC Cancer. - : BioMed Central. - 1471-2407. ; 19
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Tidskriftsartikel (refereegranskat)abstract
- Background: Clear cell renal cell carcinoma (ccRCC) is the most common subtype among renal cancer and is associated with poor prognosis if metastasized. Up to one third of patients with local disease at diagnosis will develop metastasis after nephrectomy, and there is a need for new molecular markers to identify patients with high risk of tumor progression. In the present study, we performed genome-wide promoter DNA methylation analysis at diagnosis to identify DNA methylation profiles associated with risk for progress.Method: Diagnostic tissue samples from 115 ccRCC patients were analysed by Illumina HumanMethylation450K arrays and methylation status of 155,931 promoter associated CpGs were related to genetic aberrations, gene expression and clinicopathological parameters.Results: The ccRCC samples separated into two clusters (cluster A/B) based on genome-wide promoter methylation status. The samples in these clusters differed in tumor diameter (p < 0.001), TNM stage (p < 0.001), morphological grade (p < 0.001), and patients outcome (5 year cancer specific survival (pCSS5yr) p < 0.001 and cumulative incidence of progress (pCIP5yr) p < 0.001. An integrated genomic and epigenomic analysis in the ccRCCs, revealed significant correlations between the total number of genetic aberrations and total number of hypermethylated CpGs (R = 0.435, p < 0.001), and predicted mitotic age (R = 0.407, p < 0.001). We identified a promoter methylation classifier (PMC) panel consisting of 172 differently methylated CpGs accompanying progress of disease. Classifying non-metastatic patients using the PMC panel showed that PMC high tumors had a worse prognosis compared with the PMC low tumors (pCIP5yr 38% vs. 8%, p = 0.001), which was confirmed in non-metastatic ccRCCs in the publically available TCGA-KIRC dataset (pCIP5yr 39% vs. 16%, p < 0.001).Conclusion: DNA methylation analysis at diagnosis in ccRCC has the potential to improve outcome-prediction in non-metastatic patients at diagnosis.
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| 6. |
- Andersson Evelönn, Emma, 1983-, et al.
(författare)
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DNA methylation status defines clinicopathological parameters including survival for patients with clear cell renal cell carcinoma (ccRCC)
- 2016
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Ingår i: Tumor Biology. - : Springer Science and Business Media LLC. - 1010-4283 .- 1423-0380. ; 37:8, s. 10219-10228
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Tidskriftsartikel (refereegranskat)abstract
- Epigenetic alterations in the methylome have been associated with tumor development and progression in renal cell carcinoma (RCC). In this study, 45 tumor samples, 12 tumor-free kidney cortex tissues, and 24 peripheral blood samples from patients with clear cell RCC (ccRCC) were analyzed by genome-wide promoter-directed methylation arrays and related to clinicopathological parameters. Unsupervised hierarchical clustering separated the tumors into two distinct methylation groups (clusters A and B), where cluster B had higher average methylation and increased number of hypermethylated CpG sites (CpGs). Furthermore, tumors in cluster B had, compared with cluster A, a larger tumor diameter (p = 0.033), a higher morphologic grade (p < 0.001), a higher tumor-node-metastasis (TNM) stage (p < 0.001), and a worse prognosis (p = 0.005). Higher TNM stage was correlated to an increase in average methylation level (p = 0.003) and number of hypermethylated CpGs (p = 0.003), whereas a number of hypomethylated CpGs were mainly unchanged. However, the predicted age of the tumors based on methylation profile did not correlate with TNM stage, morphological grade, or methylation cluster. Differently methylated (DM) genes (n = 840) in ccRCC samples compared with tumor-free kidney cortex samples were predominantly hypermethylated and a high proportion were identified as polycomb target genes. The DM genes were overrepresented by transcription factors, ligands, and receptors, indicating functional alterations of significance for ccRCC progression. To conclude, increased number of hypermethylated genes was associated with increased TNM stage of the tumors. DNA methylation classification of ccRCC tumor samples at diagnosis can serve as a clinically applicable prognostic marker in ccRCC.
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| 7. |
- Andersson, Ulrika, et al.
(författare)
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Telomere length, allergies and risk of Glioma
- 2017
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Ingår i: Neuro-Oncology. - : Oxford University Press. - 1522-8517 .- 1523-5866. ; 19:S3, s. 23-23
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Tidskriftsartikel (refereegranskat)abstract
- Background: In glioma, a malignant brain tumour with poor prognosis, the etiology is largely unkown. Rare inherited syndromes, and high doses of ionising radiation are associated with increased risk of glioma. Common genetic variants have been associated with risk of glioma, and familial glioma have been associated with genetic variants in genes functionally important in telomere regulation (e.g. RTEL, TERT and POT1). The association between telomere length and risk of cancer is complex and seems to be tumour type dependent. Patients with asthma have significantly shorter telomeres than those of control subjects, and a protective effect has been observed with an inverse association with allergies and asthma and glioma risk. Methods: We investigated population based glioma case-control series (431 cases and 672 controls) from Sweden at diagnosis with a quantitative PCR method for relative leukocyte telomere length measured in blood confirming with direct measurement of the association between telomere length and risk of glioma. We also explored the relationship between, age, gender, allergies and asthma, as these are established factors associated both with telomere length and glioma.Results: Longer relative leukocyte telomere length was significantly associated with increased risk of glioma, adjusting for age and gender (OR=2.23, CI: 1.11–4.47). As expected, for patients with allergies there was a protective effect with an inverse association with glioma risk, adjusting for age and gender (OR=0.64, CI; 0.48–0.85). Nevertheless, when analysing specific types of allergy, eczema (OR=0.66, CI; 0.41–1.08) and water eyes (OR=0.52, CI; 0.31–0.88) appeared to be more protective against glioma, compared to asthma (OR=0.92, CI; 0.59–1.41), and respiratory symptoms (OR=1.14, CI; 0.71–1.84) which showed no protective effect against glioma. Additionally adjusting for allergies did not markedly change the OR between relative leukocyte telomere length and glioma risk, indicating that the protective effect having allergies seems not to be coupled to telomere length. Conclusions: The adverse association of longer telomere and risk of glioma displays the complexity in understanding the biological role of telomere length and risk of developing cancer.
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| 8. |
- Andersson, Ulrika, et al.
(författare)
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The association between longer relative leukocyte telomere length and risk of glioma is independent of the potentially confounding factors allergy, BMI, and smoking
- 2019
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Ingår i: Cancer Causes and Control. - : Springer. - 0957-5243 .- 1573-7225. ; 30:2, s. 177-185
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Previous studies have suggested an association between relative leukocyte telomere length (rLTL) and glioma risk. This association may be influenced by several factors, including allergies, BMI, and smoking. Previous studies have shown that individuals with asthma and allergy have shortened relative telomere length, and decreased risk of glioma. Though, the details and the interplay between rLTL, asthma and allergies, and glioma molecular phenotype is largely unknown. Methods: rLTL was measured by qPCR in a Swedish population-based glioma case–control cohort (421 cases and 671 controls). rLTL was related to glioma risk and health parameters associated with asthma and allergy, as well as molecular events in glioma including IDH1 mutation, 1p/19q co-deletion, and EGFR amplification. Results: Longer rLTL was associated with increased risk of glioma (OR = 1.16; 95% CI 1.02–1.31). Similar to previous reports, there was an inverse association between allergy and glioma risk. Specific, allergy symptoms including watery eyes was most strongly associated with glioma risk. High body mass index (BMI) a year prior diagnosis was significantly protective against glioma in our population. Adjusting for allergy, asthma, BMI, and smoking did not markedly change the association between longer rLTL and glioma risk. rLTL among cases was not associated with IDH1 mutation, 1p/19q co-deletion, or EGFR amplification, after adjusting for age at diagnosis and sex. Conclusions: In this Swedish glioma case–control cohort, we identified that long rLTL increases the risk of glioma, an association not confounded by allergy, BMI, or smoking. This highlights the complex interplay of the immune system, rLTL and cancer risk.
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| 9. |
- Bensberg, Maike, 1993-
(författare)
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DNA methylation in T cell leukaemia
- 2024
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- T cell acute lymphoblastic leukaemia (T-ALL) is a predominantly paediatric cancer that stems from malignant transformation of developing T cells. While the disease has an overall survival rate of 80%, the intense chemotherapy treatment causes severe toxicity and long-term side effects. Furthermore, the survival rate for patients in relapse is less than 25%. Consequently, there is a need for improved therapy options to reduce treatment-related side effects and improve the survival rate of relapsed patients. Targeting aberrant DNA methylation with hypomethylating agents (HMAs) has been successful in the treatment of myelodysplastic syndromes and acute myeloid leukaemia but has not been routinely used in the treatment of T-ALL, despite DNA hypomethylation being observed in T-ALL patients. In this work, we employed a comprehensive set of molecular and sequencing-based techniques to explore the possibilities of HMAs as a treatment option for T-ALL.We made the discovery that the DNA demethylating enzyme ten-eleven translocation 2, TET2, is downregulated or completely silenced in primary T-ALL. Moreover, the TET2 promoter was highly methylated in a group of patients, suggesting that TET2 itself can be silenced through DNA methylation in T-ALL. By treatment with HMAs, TET2 was demethylated in T-ALL cell lines and was one of few genes that was activated upon loss of DNA methylation, indicating that TET2 expression is regulated by DNA methylation in T-ALL cell lines. The development of a novel HMA, the DNMT1-specific inhibitor GSK-3685032, offers a tool to reveal the mechanism of action of the traditional HMAs, 5- azacytidine and decitabine, and to study the effects of acute loss of DNA methylation on cancer cells. We found that 5-azacytidine and decitabine are cytotoxic to T-ALL cells primarily by creating DNA double strand breaks. In contrast, GSK did not prompt a DNA damage response and instead reduced global DNA methylation to as little as 18% with limited cytotoxicity only occurring after levels of DNA methylation had dropped below 30%, a level of demethylation not achieved with DEC or AZA.T-ALL is more than two times more common in boys than girls and mutations in X-linked tumour suppressor genes that escape X inactivation, have been suggested as an underlying cause for the observed sex-bias. In theory, these aberrations would be more detrimental in XYmale cells than in XX-female cells due to the presence of an extra protective copy of the gene in females. We profiled DNA methylation during T cell development and created a map of sex-specific gene expression and expression from the inactive X chromosome, finding that some, but not all, suggested tumour suppressor genes in fact escape X inactivation. These results highlight the importance of profiling the healthy cells that T-ALL arises from to correctly judge the functional impact of gene dysregulation in cancer.In the last study, we aimed to investigate the role of N6-adenine methylation (6mdA) during T cell differentiation. While 6mdA is common in bacteria it is much rarer in humans. Nevertheless, 6mdA has previously been associated with several cellular processes, including cancer progression. Our study calls the presence of 6mdA in mammals into question by exposing limitations of the techniques used in its analysis. We show that contamination with bacterial DNA or 6mAcontaining RNA, nonspecific antibody binding, and low precision of third-generation sequencing techniques all hinder the detection and investigation of rare DNA modifications, such as 6mdA.Together, this work is an in-depth study of the function and the potential of DNA methylation in the biology of healthy and malignant T cells.
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| 10. |
- Borssén, Magnus, et al.
(författare)
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DNA Methylation Adds Prognostic Value to Minimal Residual Disease Status in Pediatric T-Cell Acute Lymphoblastic Leukemia
- 2016
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Ingår i: Pediatric Blood & Cancer. - : Wiley. - 1545-5009 .- 1545-5017. ; 63:7, s. 1185-1192
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Tidskriftsartikel (refereegranskat)abstract
- Background. Despite increased knowledge about genetic aberrations in pediatric T-cell acute lymphoblastic leukemia (T-ALL), no clinically feasible treatment-stratifying marker exists at diagnosis. Instead patients are enrolled in intensive induction therapies with substantial side effects. In modern protocols, therapy response is monitored by minimal residual disease (MRD) analysis and used for postinduction risk group stratification. DNA methylation profiling is a candidate for subtype discrimination at diagnosis and we investigated its role as a prognostic marker in pediatric T-ALL. Procedure. Sixty-five diagnostic T-ALL samples from Nordic pediatric patients treated according to the Nordic Society of Pediatric Hematology and Oncology ALL 2008 (NOPHO ALL 2008) protocol were analyzed by HumMeth450K genome wide DNA methylation arrays. Methylation status was analyzed in relation to clinical data and early T-cell precursor (ETP) phenotype. Results. Two distinct CpG island methylator phenotype (CIMP) groups were identified. Patients with a CIMP-negative profile had an inferior response to treatment compared to CIMP-positive patients (3-year cumulative incidence of relapse (CIR3y) rate: 29% vs. 6%, P = 0.01). Most importantly, CIMP classification at diagnosis allowed subgrouping of high-risk T-ALL patients (MRD >= 0.1% at day 29) into two groups with significant differences in outcome (CIR3y rates: CIMP negative 50% vs. CIMP positive 12%; P = 0.02). These groups did not differ regarding ETP phenotype, but the CIMP-negative group was younger (P = 0.02) and had higher white blood cell count at diagnosis (P = 0.004) compared with the CIMP-positive group. Conclusions. CIMP classification at diagnosis in combination with MRD during induction therapy is a strong candidate for further risk classification and could confer important information in treatment decision making.
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| 11. |
- Borssén, Magnus, 1977-
(författare)
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DNA methylation as a prognostic marker i acute lymphoblastic leukemia
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy. Most ALL cases originate from immature B-cells (BCP-ALL) and are characterized by reoccurring structural genetic aberrations. These aberrations hold information of the pathogenesis of ALL and are used for risk stratification in treatment. Despite increased knowledge of genetic aberrations in pediatric T-cell ALL (T-ALL), no reliable molecular genetic markers exist for identifying patients with higher risk of relapse. The lack of molecular prognostic markers is also evident in patients with relapsed ALL. During the last decades, aberrant epigenetic mechanisms including DNA methylation have emerged as important components in cancer development. Telomere maintenance is another important factor in malignant transformation and is crucial for long-term cell survival. Like DNA methylation, telomere length maintenance has also been implicated to reflect outcomes for patients with leukemia.In this thesis, the prognostic relevance of DNA methylation and telomere length was investigated in pediatric ALL at diagnosis and relapse. The telomere length (TL) was significantly shorter in diagnostic ALL samples compared to normal bone marrow samples collected at cessation of therapy, reflecting the proliferation associated telomere length shortening. Prognostic relevance of TL was shown in low-risk BCP-ALL patients where longer telomeres at diagnosis were associated with higher risk of relapse.Genome-wide methylation characterization by arrays in diagnostic T-ALL samples identified two distinct methylation subgroups denoted CIMP+ (CpG Island Methylator Phenotype high) and CIMP- (low). CIMP- T-ALL patients had significantly worse outcome compared to CIMP+ cases. These results were confirmed in a Nordic cohort treated according to the current NOPHO-ALL2008 protocol. By combining minimal residual disease (MRD) status at treatment day 29 and CIMP status at diagnosis we could further separate T-ALL patients into risk groups.Likewise, the CIMP profile could separate relapsed BCP-ALL patients into risk groups, where the CIMP- cases had a significantly worse outcome compared to CIMP+ cases. From these data we conclude that DNA methylation subgrouping is a promising prognostic marker in T-ALL, as well as in relapsed BCP-ALL two groups where reliable prognostic markers are currently missing. By elucidating the biology behind the different CIMP profiles, the pathogenesis of ALL will be further understood and may contribute to new treatment strategies.
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| 12. |
- Borssén, Magnus, et al.
(författare)
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DNA methylation holds prognostic information in relapsed precursor B-cell acute lymphoblastic leukemia
- 2018
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Ingår i: Clinical Epigenetics. - : BIOMED CENTRAL LTD. - 1868-7083 .- 1868-7075. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Background: Few biological markers are associated with survival after relapse of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). In pediatric T-cell ALL, we have identified promoter-associated methylation alterations that correlate with prognosis. Here, the prognostic relevance of CpG island methylation phenotype (CIMP) classification was investigated in pediatric BCP-ALL patients.Methods: Six hundred and one BCP-ALL samples from Nordic pediatric patients (age 1-18) were CIMP classified at initial diagnosis and analyzed in relation to clinical data.Results: Among the 137 patients that later relapsed, patients with a CIMP-profile (n = 42) at initial diagnosis had an inferior overall survival (pOS(5years) 33%) compared to CIMP+ patients (n = 95, pOS(5years) 65%) (p = 0.001), which remained significant in a Cox proportional hazards model including previously defined risk factors.Conclusion: CIMP classification is a strong candidate for improved risk stratification of relapsed BCP-ALL.
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| 13. |
- Borssen, Magnus, et al.
(författare)
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Promoter DNA methylation pattern identifies prognostic subgroups in childhood T-cell acute lymphoblastic leukemia.
- 2013
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Ingår i: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 8:6
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Tidskriftsartikel (refereegranskat)abstract
- Treatment of pediatric T-cell acute lymphoblastic leukemia (T-ALL) has improved, but there is a considerable fraction of patients experiencing a poor outcome. There is a need for better prognostic markers and aberrant DNA methylation is a candidate in other malignancies, but its potential prognostic significance in T-ALL is hitherto undecided.
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| 14. |
- Bovinder Ylitalo, Erik, et al.
(författare)
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A novel DNA methylation signature is associated with androgen receptor activity and patient prognosis in bone metastatic prostate cancer
- 2021
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Ingår i: Clinical Epigenetics. - : BioMed Central. - 1868-7083 .- 1868-7075. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Patients with metastatic prostate cancer (PC) are treated with androgen deprivation therapy (ADT) that initially reduces metastasis growth, but after some time lethal castration-resistant PC (CRPC) develops. A better understanding of the tumor biology in bone metastases is needed to guide further treatment developments. Subgroups of PC bone metastases based on transcriptome profiling have been previously identified by our research team, and specifically, heterogeneities related to androgen receptor (AR) activity have been described. Epigenetic alterations during PC progression remain elusive and this study aims to explore promoter gene methylation signatures in relation to gene expression and tumor AR activity.Materials and methods: Genome-wide promoter-associated CpG methylation signatures of a total of 94 tumor samples, including paired non-malignant and malignant primary tumor areas originating from radical prostatectomy samples (n = 12), and bone metastasis samples of separate patients with hormone-naive (n = 14), short-term castrated (n = 4) or CRPC (n = 52) disease were analyzed using the Infinium Methylation EPIC arrays, along with gene expression analysis by Illumina Bead Chip arrays (n = 90). AR activity was defined from expression levels of genes associated with canonical AR activity.Results: Integrated epigenome and transcriptome analysis identified pronounced hypermethylation in malignant compared to non-malignant areas of localized prostate tumors. Metastases showed an overall hypomethylation in relation to primary PC, including CpGs in the AR promoter accompanied with induction of AR mRNA levels. We identified a Methylation Classifier for Androgen receptor activity (MCA) signature, which separated metastases into two clusters (MCA positive/negative) related to tumor characteristics and patient prognosis. The MCA positive metastases showed low methylation levels of genes associated with canonical AR signaling and patients had a more favorable prognosis after ADT. In contrast, MCA negative patients had low AR activity associated with hypermethylation of AR-associated genes, and a worse prognosis after ADT.Conclusions: A promoter methylation signature classifies PC bone metastases into two groups and predicts tumor AR activity and patient prognosis after ADT. The explanation for the methylation diversities observed during PC progression and their biological and clinical relevance need further exploration.
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| 15. |
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| 16. |
- Carlund, Olivia, et al.
(författare)
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DNA methylation variations and epigenetic aging in telomere biology disorders
- 2023
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Ingår i: Scientific Reports. - : Springer Nature. - 2045-2322. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- Telomere Biology Disorders (TBDs) are characterized by mutations in telomere-related genes leading to short telomeres and premature aging but with no strict correlation between telomere length and disease severity. Epigenetic alterations are also markers of aging and we aimed to evaluate whether DNA methylation (DNAm) could be part of the pathogenesis of TBDs. In blood from 35 TBD cases, genome-wide DNAm were analyzed and the cases were grouped based on relative telomere length (RTL): short (S), with RTL close to normal controls, and extremely short (ES). TBD cases had increased epigenetic age and DNAm alterations were most prominent in the ES-RTL group. Thus, the differentially methylated (DM) CpG sites could be markers of short telomeres but could also be one of the mechanisms contributing to disease phenotype since DNAm alterations were observed in symptomatic, but not asymptomatic, cases with S-RTL. Furthermore, two or more DM-CpGs were identified in four genes previously linked to TBD or telomere length (PRDM8, SMC4, VARS, and WNT6) and in three genes that were novel in telomere biology (MAS1L, NAV2, and TM4FS1). The DM-CpGs in these genes could be markers of aging in hematological cells, but they could also be of relevance for the progression of TBD.
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| 17. |
- Carlund, Olivia, et al.
(författare)
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Semimethylation is a feature of diffuse large B-cell lymphoma, and subgroups with poor prognosis are characterized by global hypomethylation and short telomere length
- 2024
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Ingår i: Clinical Epigenetics. - : BioMed Central (BMC). - 1868-7083. ; 16:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Large B-cell lymphoma (LBCL) is the most common lymphoma and is known to be a biologically heterogeneous disease regarding genetic, phenotypic, and clinical features. Although the prognosis is good, one-third has a primary refractory or relapsing disease which underscores the importance of developing predictive biological markers capable of identifying high- and low-risk patients. DNA methylation (DNAm) and telomere maintenance alterations are hallmarks of cancer and aging. Both these alterations may contribute to the heterogeneity of the disease, and potentially influence the prognosis of LBCL.Results: We studied the DNAm profiles (Infinium MethylationEPIC BeadChip) and relative telomere lengths (RTL) with qPCR of 93 LBCL cases: Diffuse large B-cell lymphoma not otherwise specified (DLBCL, n = 66), High-grade B-cell lymphoma (n = 7), Primary CNS lymphoma (n = 8), and transformation of indolent B-cell lymphoma (n = 12). There was a substantial methylation heterogeneity in DLBCL and other LBCL entities compared to normal cells and other B-cell neoplasms. LBCL cases had a particularly aberrant semimethylated pattern (0.15 ≤ β ≤ 0.8) with large intertumor variation and overall low hypermethylation (β > 0.8). DNAm patterns could not be used to distinguish between germinal center B-cell-like (GC) and non-GC DLBCL cases. In cases treated with R-CHOP-like regimens, a high percentage of global hypomethylation (β < 0.15) was in multivariable analysis associated with worse disease-specific survival (DSS) (HR 6.920, 95% CI 1.499–31.943) and progression-free survival (PFS) (HR 4.923, 95% CI 1.286–18.849) in DLBCL and with worse DSS (HR 5.147, 95% CI 1.239–21.388) in LBCL. These cases with a high percentage of global hypomethylation also had a higher degree of CpG island methylation, including islands in promoter-associated regions, than the cases with less hypomethylation. Additionally, telomere length was heterogenous in LBCL, with a subset of the DLBCL-GC cases accounting for the longest RTL. Short RTL was independently associated with worse DSS (HR 6.011, 95% CI 1.319–27.397) and PFS (HR 4.689, 95% CI 1.102–19.963) in LBCL treated with R-CHOP-like regimens.Conclusion: We hypothesize that subclones with high global hypomethylation and hypermethylated CpG islands could have advantages in tumor progression, e.g. by inactivating tumor suppressor genes or promoting treatment resistance. Our findings suggest that cases with high global hypomethylation and thus poor prognosis could be candidates for alternative treatment regimens including hypomethylating drugs.
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| 18. |
- Degerman, Sofie, et al.
(författare)
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Immortalization of T-Cells Is Accompanied by Gradual Changes in CpG Methylation Resulting in a Profile Resembling a Subset of T-Cell Leukemias
- 2014
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Ingår i: Neoplasia. - : Elsevier BV. - 1522-8002 .- 1476-5586. ; 16:7, s. 606-615
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Tidskriftsartikel (refereegranskat)abstract
- We have previously described gene expression changes during spontaneous immortalization of T-cells, thereby identifying cellular processes important for cell growth crisis escape and unlimited proliferation. Here, we analyze the same model to investigate the role of genome-wide methylation in the immortalization process at different time points pre-crisis and post-crisis using high-resolution arrays. We show that over time in culture there is an overall accumulation of methylation alterations, with preferential increased methylation close to transcription start sites (TSSs), islands, and shore regions. Methylation and gene expression alterations did not correlate for the majority of genes, but for the fraction that correlated, gain of methylation close to TSS was associated with decreased gene expression. Interestingly, the pattern of CpG site methylation observed in immortal T-cell cultures was similar to clinical T-cell acute lymphoblastic leukemia (T-ALL) samples classified as CpG island methylator phenotype positive. These sites were highly overrepresented by polycomb target genes and involved in developmental, cell adhesion, and cell signaling processes. The presence of non-random methylation events in in vitro immortalized T-cell cultures and diagnostic T-ALL samples indicates altered methylation of CpG sites with a possible role in malignant hematopoiesis.
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| 19. |
- Degerman, Sofie, et al.
(författare)
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Long Leukocyte Telomere Length at Diagnosis Is a Risk Factor for Dementia Progression in Idiopathic Parkinsonism
- 2014
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:12
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Tidskriftsartikel (refereegranskat)abstract
- Telomere length (TL) is regarded as a marker of cellular aging due to the gradual shortening by each cell division, but is influenced by a number of factors including oxidative stress and inflammation. Parkinson's disease and atypical forms of parkinsonism occur mainly in the elderly, with oxidative stress and inflammation in afflicted cells. In this study the relationship between blood TL and prognosis of 168 patients with idiopathic parkinsonism (136 Parkinson's disease [PD], 17 Progressive Supranuclear Palsy [PSP], and 15 Multiple System Atrophy [MSA]) and 30 controls was investigated. TL and motor and cognitive performance were assessed at baseline (diagnosis) and repeatedly up to three to five years follow up. No difference in TL between controls and patients was shown at baseline, nor any significant difference in TL stability or attrition during follow up. Interestingly, a significant relationship between TL at diagnosis and cognitive phenotype at follow up in PD and PSP patients was found, with longer mean TL at diagnosis in patients that developed dementia within three years.
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| 20. |
- Degerman, Sofie, et al.
(författare)
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Maintained memory in aging is associated with young epigenetic age
- 2017
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Ingår i: Neurobiology of Aging. - : Elsevier. - 0197-4580 .- 1558-1497. ; 55, s. 167-171
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Tidskriftsartikel (refereegranskat)abstract
- Epigenetic alterations during aging have been proposed to contribute to decline in physical and cognitive functions, and accelerated epigenetic aging has been associated with disease and all-cause mortality later in life. In this study, we estimated epigenetic age dynamics in groups with different memory trajectories (maintained high performance, average decline, and accelerated decline) over a 15-year period. Epigenetic (DNA-methylation [DNAm]) age was assessed, and delta age (DNAm age - chronological age) was calculated in blood samples at baseline (age: 55-65 years) and 15 years later in 52 age- and gender-matched individuals from the Betula study in Sweden. A lower delta DNAm age was observed for those with maintained memory functions compared with those with average (p = 0.035) or accelerated decline (p = 0.037). Moreover, separate analyses revealed that DNAm age at follow-up, but not chronologic age, was a significant predictor of dementia (p = 0.019). Our findings suggest that young epigenetic age contributes to maintained memory in aging.
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| 21. |
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| 22. |
- Degerman, Sofie, 1977-, et al.
(författare)
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Telomerase upregulation is a postcrisis event during senescence bypass and immortalization of two Nijmegen breakage syndrome T cell cultures
- 2010
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Ingår i: Aging Cell. - : John Wiley & Sons. - 1474-9718 .- 1474-9726. ; 9, s. 220-235
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Tidskriftsartikel (refereegranskat)abstract
- Summary Our knowledge on immortalization and telomere biology is mainly based on genetically manipulated cells analyzed before and many population doublings post growth crisis. The general view is that growth crisis is telomere length (TL) dependent and that escape from crisis is coupled to increased expression of the telomerase reverse transcriptase (hTERT) gene, telomerase activity upregulation and TL stabilization. Here we have analyzed the process of spontaneous immortalization of human T cells, regarding pathways involved in senescence and telomerase regulation. Two Nijmegen breakage syndrome (NBS) T cell cultures (S3R and S4) showed gradual telomere attrition until a period of growth crisis followed by the outgrowth of immortalized cells. Whole genome expression analysis indicated differences between pre-, early post- and late postcrisis cells. Early postcrisis cells demonstrated a logarithmic growth curve, very short telomeres and, notably, no increase in hTERT or telomerase activity despite downregulation of several negative hTERT regulators (e.g. FOS, JUN D, SMAD3, RUNX2, TNF-alpha and TGFbeta-R2). Thereafter, cMYC mRNA increased in parallel with increased hTERT expression, telomerase activity and elongation of short telomeres, indicating a step-wise activation of hTERT transcription involving reduction of negative regulators followed by activation of positive regulator(s). Gene expression analysis indicated that cells escaped growth crisis by deregulated DNA damage response and senescence controlling genes, including downregulation of ATM, CDKN1B (p27), CDKN2D (p19) and ASF1A and upregulation of CDK4, TWIST1, TP73L (p63) and SYK. Telomerase upregulation was thus found to be uncoupled to escape of growth crisis but rather a later event in the immortalization process of NBS T cell cultures.
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| 23. |
- Degerman, Sofie, 1977-
(författare)
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The immortalization process of T cells : with focus on the regulation of telomere length and telomerase activity
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Cellular immortalization is a major hallmark of cancer and is a multi-step process that requires numerous cell-type specific changes, including inactivation of control mechanisms and stabilization of telomere length. The telomeres at the chromosome ends are essential for genomic stability, and limit the growth potential of most cells. With each cell division, telomeres are shortened. Short telomeres may induce an irreversible growth arrest stage called senescence, or a growth crisis stage characterized by high genomic instability and cell death. Only very rarely do cells escape from crisis and become immortal, a stage that has been associated with the activation of the telomerase enzyme which can elongate and stabilize the telomeres. The processes leading to senescence bypass, growth crisis escape and finally immortalization are only beginning to be elucidated. Most of our knowledge of the immortalization process is based on analyses of human fibroblast and epithelial cell cultures immortalized by genetic modification. In this thesis, spontaneously immortalized human T lymphocytes derived from patients with Nijmegen Breakage Syndrome and a healthy individual were used to identify critical events for senescence bypass and immortalization. Genetic analysis showed a clonal progression and non-random genetic changes including the amplification of chromosomal region 2p13-21 as an early event in the immortalization process. Telomere length gradually shortened at increasing population doublings and growth crisis was associated with critically short telomeres. The clone(s) that escaped growth crisis demonstrated a logarithmic growth curve, very short telomeres and, notably, no increase in telomerase activity or expression of the telomerase catalytic gene, hTERT. Instead, upregulation of telomerase activity and telomere length stabilization were late events in T lymphocyte immortalization. Escape from crisis was associated with downregulation of DNA damage response genes and altered expression of cell cycle regulators and genes controlling the cellular senescence program. These data indicated that a number of layers of regulation are important in the process of immortalization and to provide further mechanistic detail, epigenetic analysis was carried out. Genome wide methylation array analysis identified early and step-wise methylation changes during the immortalization process. Interestingly, applying these findings to tumors of T cell origin revealed commonly methylated CpG sites in transformed cells. Deregulated gene expression of the polycomb complexes may have contributed to the epigenetic changes observed. Taken together, our analysis of spontaneously immortalized T cell cultures identified several steps in the immortalization process including genetic, epigenetic, gene expression and telomere/telomerase regulatory events, contributing further insights to the complexity of cancer cell immortalization.
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| 24. |
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| 25. |
- Fogelstrand, Linda, 1974, et al.
(författare)
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Prognostic Implications of Mutations in NOTCH1 and FBXW7 in Childhood T-ALL Treated According to the NOPHO ALL-1992 and ALL-2000 Protocols
- 2014
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Ingår i: Pediatric Blood & Cancer. - : Wiley-Blackwell. - 1545-5009 .- 1545-5017. ; 61:3, s. 424-430
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Tidskriftsartikel (refereegranskat)abstract
- Background In children, T-cell acute lymphoblastic leukemia (T-ALL) has inferior prognosis compared with B-cell precursor ALL. In order to improve survival, individualized treatment strategies and thus risk stratification algorithms are warranted, ideally already at the time of diagnosis.Procedure We analyzed the frequency and prognostic implication of mutations in NOTCH1 and FBXW7 in 79 cases of Swedish childhood T-ALL treated according to the Nordic Society of Pediatric Hematology and Oncology (NOPHO) ALL-1992 and ALL-2000 protocols. In a subgroup of patients, we also investigated the functional relevance of NOTCH1 mutations measured as expression of the HES1, MYB, and MYC genes.Results Forty-seven of the cases (59%) displayed mutations in NOTCH1 and/or FBXW7. There was no difference in overall (P=0.14) or event-free survival (EFS) (P=0.10) in patients with T-ALL with mutation(s) in NOTCH1/FBXW7 compared with patients with T-ALL without mutations in any of these genes. T-ALL carrying NOTCH1 mutations had increased HES1 and MYB mRNA expression (HES1 9.21.9 (mean +/- SEM), MYB 8.7 +/- 0.8 (mean +/- SEM)) compared to T-ALL with wild-type NOTCH1 (HES1 1.8 +/- 0.7, MYB 5.1 +/- 1.2, P=0.02 and 0.008, respectively). In cases of T-ALL with high HES1 expression, improved overall (P=0.02) and EFS (P=0.028) was seen.Conclusions Increased NOTCH activity, reflected by increased HES1 expression, is associated with improved outcome in pediatric T-ALL, but its role as a diagnostic tool or a therapeutic target in future clinical treatment protocols remains to be elucidated. Pediatr Blood Cancer 2014;61:424-430. (c) 2013 Wiley Periodicals, Inc.
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