| 1. |
- Berglund, Erik, et al.
(author)
-
Evidence for Ca2+-regulated ATP release in gastrointestinal stromal tumors
- 2013
-
In: Experimental Cell Research. - : Elsevier BV. - 0014-4827 .- 1090-2422. ; 319:8, s. 1229-1238
-
Journal article (peer-reviewed)abstract
- Gastrointestinal stromal tumors (GISTs) are thought to originate from the electrically active pacemaker cells of the gastrointestinal tract. Despite the presence of synaptic-like vesicles and proteins involved in cell secretion it remains unclear whether GIST cells possess regulated release mechanisms. The GIST tumor cell line GIST882 was used as a model cell system, and stimulus-release coupling was investigated by confocal microscopy of cytoplasmic free Ca2+ concentration ([Ca(2+)1](i)), flow cytometry, and luminometric measurements of extracellular ATP. We demonstrate that GIST cells have an intact intracellular Ca2+-signaling pathway that regulates ATP release. Cell viability and cell membrane integrity was preserved, excluding ATP leakage due to cell death and suggesting active ATP release. The stimulus-secretion signal transduction is at least partly dependent on Ca2+ influx since exclusion of extracellular Ca2+ diminishes the ATP release. We conclude that measurements of ATP release in GISTs may be a useful tool for dissecting the signal transduction pathway, mapping exocytotic components, and possibly for the development and evaluation of drugs. Additionally, release of ATP from GISTs may have importance for tumor tissue homeostasis and immune surveillance escape.
|
|
| 2. |
|
|
| 3. |
- Binzer-Panchal, Amrei, et al.
(author)
-
Integrated Molecular Analysis of Undifferentiated Uterine Sarcomas Reveals Clinically Relevant Molecular Subtypes
- 2019
-
In: Clinical Cancer Research. - : AMER ASSOC CANCER RESEARCH. - 1078-0432 .- 1557-3265. ; 25:7, s. 2155-2165
-
Journal article (peer-reviewed)abstract
- Purpose: Undifferentiated uterine sarcomas (UUS) are rare, extremely deadly, sarcomas with no effective treatment. The goal of this study was to identify novel intrinsic molecular UUS subtypes using integrated clinical, histopathologic, and molecular evaluation of a large, fully annotated, patient cohort.Experimental Design: Fifty cases of UUS with full clinicopathologic annotation were analyzed for gene expression (n = 50), copy-number variation (CNV, n = 40), cell morphometry (n = 39), and protein expression (n = 22). Gene ontology and network enrichment analysis were used to relate over-and underexpressed genes to pathways and further to clinicopathologic and phenotypic findings.Results: Gene expression identified four distinct groups of tumors, which varied in their clinicopathologic parameters. Gene ontology analysis revealed differential activation of pathways related to genital tract development, extracellular matrix (ECM), muscle function, and proliferation. A multivariable, adjusted Cox proportional hazard model demonstrated that RNA group, mitotic index, and hormone receptor expression influence patient overall survival (OS). CNV arrays revealed characteristic chromosomal changes for each group. Morphometry demonstrated that the ECM group, the most aggressive, exhibited a decreased cell density and increased nuclear area. A cell density cutoff of 4,300 tumor cells per mm(2) could separate ECM tumors from the remaining cases with a sensitivity of 83% and a specificity of 94%. IHC staining of MMP-14, Collagens 1 and 6, and Fibronectin proteins revealed differential expression of these ECM-related proteins, identifying potential new biomarkers for this aggressive sarcoma subgroup. Conclusions: Molecular evaluation of UUS provides novel insights into the biology, prognosis, phenotype, and possible treatment of these tumors.
|
|
| 4. |
- Fotouhi, Omid, et al.
(author)
-
Proteomics identifies neddylation as a potential therapy target in small intestinal neuroendocrine tumors
- 2019
-
In: Oncogene. - : NATURE PUBLISHING GROUP. - 0950-9232 .- 1476-5594. ; 38:43, s. 6881-6897
-
Journal article (peer-reviewed)abstract
- Patients with small intestinal neuroendocrine tumors (SI-NETs) frequently develop spread disease; however, the underlying molecular mechanisms of disease progression are not known and effective preventive treatment strategies are lacking. Here, protein expression profiling was performed by HiRIEF-LC-MS in 14 primary SI-NETs from patients with and without liver metastases detected at the time of surgery and initial treatment. Among differentially expressed proteins, overexpression of the ubiquitin-like protein NEDD8 was identified in samples from patients with liver metastasis. Further, NEDD8 correlation analysis indicated co-expression with RBX1, a key component in cullin-RING ubiquitin ligases (CRLs). In vitro inhibition of neddylation with the therapeutic agent pevonedistat (MLN4924) resulted in a dramatic decrease of proliferation in SI-NET cell lines. Subsequent mass spectrometry-based proteomics analysis of pevonedistat effects and effects of the proteasome inhibitor bortezomib revealed stabilization of multiple targets of CRLs including p27, an established tumor suppressor in SI-NET. Silencing of NEDD8 and RBX1 using siRNA resulted in a stabilization of p27, suggesting that the cellular levels of NEDD8 and RBX1 affect CRL activity. Inhibition of CRL activity, by either NEDD8/RBX1 silencing or pevonedistat treatment of cells resulted in induction of apoptosis that could be partially rescued by siRNA-based silencing of p27. Differential expression of both p27 and NEDD8 was confirmed in a second cohort of SI-NET using immunohistochemistry. Collectively, these findings suggest a role for CRLs and the ubiquitin proteasome system in suppression of p27 in SI-NET, and inhibition of neddylation as a putative therapeutic strategy in SI-NET.
|
|
| 5. |
- Ghaderi, Mehran
(author)
-
HLA predisposition to human papillomavirus induced cervical neoplasia : population based studies from the Västerbotten county in northern Sweden
- 2001
-
Doctoral thesis (other academic/artistic)abstract
- Infection with human papillomaviruses (HPV) types 16 and 18 is the major cause of cervical neoplasia. Although a high proportion of cervical cancers (CXCA) harbor HPV genomes, only a small number of women infected with high-risk papillomaviruses develop cervical tumors, suggesting that other environmental and/or genetic factors contribute to cervical carcinogenesis. Several studies have identified genes encoding human leukocyte antigens (HLA) associated with cervical intraepithelial neoplasia (CIN) and CXCA. Many genes encoding the products involved in immune responses are clustered within the human major histocompatibility complex (MHC) on the short arm of chromosome 6 (6p21.3). The human AMC extends over 3500 kilobases and comprises more than 200 genes with known and unknown functions The HLA class I genes encodes cell surface glycoproteins (HLA-A, -B, -C) that associates in the endoplasmic reticulum with beta32-microglubulin and peptides derived from endogenously processed antigens. HLA class II genes encode cell surface glycoproteins, which bind to peptides that originate mainly from exogenous antigens processed through the endosomal/lysosomal pathway. In addition to HLA class I and class II molecules, genes that encode the cytokines, tumor necrosis factor (TNF) alpha and beta are located in the class III region. The MHC class I chain related genes (MICA/B) located in the centromeric end of the HLA class I region, have recently been in focus for it can function as a ligand for gamma/delta T cells and NK cell receptors. MICA protein is mainly expressed by epithelial cells and its interaction with NK cells and gamma/delta T cells might have a role in the pathogenesis of CXCA. The aim of this thesis was to investigate the association of candidate HLA genes with CIN and CXCA. Several different genotyping methods were used to study the polymorphic HLA genes in two different patient groups. Patients and controls from a cohort of Västerbotten were included in this population-based study. Candidate genes in the HLA class I, class II and class III region were analyzed and their association with CXCA and susceptibility to HPV infection was measured using appropriate statistical methods. The strongest association of HLA genes with CXCA was found in the HLA class II locus. The relative risks of CXCA among DR15 and DQ6 (DQB1*0602) positive patients were 3.73 and 4.33, corresponding to population attributable proportions of 27.9% and 30.8%, respectively. MICA was not associated with either CIN or CXCA. The polymorphism of the TNFA gene was associated with susceptibility to HPV 16 infection and increased the risk for CIN and CXCA in patients with the DR15-DQ6 haplotype.
|
|
| 6. |
- Ghaderi, Mehran, et al.
(author)
-
MHC2TA single nucleotide polymorphism and genetic risk for autoimmune adrenal insufficiency
- 2006
-
In: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 91:10, s. 4107-4111
-
Journal article (peer-reviewed)abstract
- CONTEXT: The polymorphism of class II HLA genes modulates the genetic risk for several endocrine autoimmune diseases. The constitutive class II expression on antigen-presenting cells is under the control of the MHC class II transactivator, encoded by the MHC2TA gene, which is mapped to chromosome 16p13. The MHC2TA -168 A-->G single nucleotide polymorphism (rs3087456) has been suggested to confer susceptibility to some autoimmune diseases. DESIGN: With the aim of testing whether this MHC2TA single nucleotide polymorphism is independently associated with autoimmune Addison's disease (AAD) and/or modulates the genetic risk conferred by DRB1-DQA1-DQB1 haplotypes, we analyzed DNA samples from 128 AAD patients and 406 healthy control subjects from continental Italy. RESULTS: Frequency of allele G of MHC2TA was significantly increased among AAD patients (39% alleles), compared with 29% in healthy controls (P = 0.003). Similarly, the frequency of AG+GG genotypes was significantly higher among AAD patients than among healthy control subjects, in both a codominant (P = 0.012) and a G-dominant model (P = 0.018). Multivariate logistic regression analysis showed that MHC2TA AG+GG continued to be positively associated with genetic risk for AAD (P = 0.028, odds ratio = 1.72, 95% confidence interval = 1.06-2.78), after correction for DRB1*03-DQA1*0501-DQB1*0201, DRB1*04 (not 0403)-DQA1*0301-DQB1*0302 and DRB1*0403. Similar results were obtained when the number of G alleles was included in the model (P = 0.004; odds ratio = 1.65, 95% confidence interval = 1.17-2.32). CONCLUSIONS: Our study provides the first demonstration of the association of the polymorphism of the MHC2TA gene with genetic risk for AAD that appears to be independent from the well-known association with the polymorphism of HLA class II genes.
|
|
| 7. |
- Gharizadeh, Baback, et al.
(author)
-
Methodological improvements of pyrosequencing technology
- 2006
-
In: Journal of Biotechnology. - : Elsevier BV. - 0168-1656 .- 1873-4863. ; 124:3, s. 504-511
-
Journal article (peer-reviewed)abstract
- Pyrosequencing technology is a rather novel DNA sequencing method based on the sequencing-by-synthesis principle. This bioluminometric, real-time DNA sequencing technique employs a cascade of four enzymatic reactions producing sequence peak signals. The method has been proven highly suitable for single nucleotide polymorphism analysis and sequencing of short stretches of DNA. Although the pyrosequencing procedure is relatively straightforward, users may face challenges due to varying parameters in PCR and sequencing primer design, sample preparation and nucleotide dispensation; such challenges are labor and cost intensive. In this study, these issues have been addressed to increase signal quality and assure sequence accuracy.
|
|
| 8. |
- Gharizadeh, Baback, et al.
(author)
-
Sentinel-base DNA genotyping using multiple sequencing primers for high-risk human papillomaviruses
- 2006
-
In: Mol Cell Probes. - : Elsevier BV. ; 20:3-4, s. 230-238
-
Journal article (peer-reviewed)abstract
- Despite the various technologies in place for genotyping human papillomaviruses (HPV), clinical use and clinical research demand a method that is fast, more reliable and cost-effective. The technology described here represents a breakthrough development in that direction. By combining the method of multiple sequencing primers with DNA sequencing, we have developed a rapid assay for genotyping HPV that relies on the identification of a single, type-specific 'sentinel' base. As described here, the prototype assay has been developed to recognize the 12 most high-risk HPV types (HPV-16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58 and 59) and is capable of recognizing and simultaneously genotyping multiple HPV co-infections. By providing sequence information on multiple HPV infections, this method eliminates the need for labor- and cost-intensive PCR cloning. These proof-of-concept studies establish the assay to be accurate, reliable, rapid, flexible, and cost-effective, providing evidence of the feasibility this technique for use in clinical settings.
|
|
| 9. |
- Gremel, Gabriela, et al.
(author)
-
A prognosis based classification of undifferentiated uterine sarcomas : Identification of mitotic index, hormone receptors and YWHAE-FAM22 translocation status as predictors of survival
- 2015
-
In: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 136:7, s. 1608-1618
-
Journal article (peer-reviewed)abstract
- Undifferentiated uterine sarcomas (UUS) are rare tumors with a heterologous biology and a poor prognosis. The goal of this study was to examine clinicopathology, biomarkers and YWHAE-FAM22 translocation status, in the prognosis of these tumors. Twenty-six cases of UUS were included. All original slides were rereviewed and age at diagnosis, tumor stage, Kurihara diagnosis, mitotic index, presence of necrosis and grade of nuclear atypia were recorded. Additionally, a tissue microarray was constructed from 22 of the cases, and the protein biomarkers P53, P16, Ki-67, Cyclin-D1, ER, PR and ANLN were evaluated by immunohistochemistry. All tumors were evaluated for the presence of a YWHAE-FAM translocation; the translocation was demonstrated in the three Cyclin-D1 positive tumors. Follow-up data in the form of overall survival were available on all patients. These tumors could be divided into two prognostic groups, a high mitotic index group (10 cases, M=36.8, SD=5.4) and a low mitotic index group (16 cases, M=8.7, SD=5.8). These two groups showed a statistically significant difference in prognosis. The expression of ER, PR or presence of the YWHAE-FAM22 translocation correlated with low mitotic index and an additionally improved prognosis, although the number of cases was small. These results indicate that UUS can be divided into two prognostic groups using mitotic index as a primary criteria, followed by expression of either ER, PR or the presence of a YWHAE-FAM22 translocation as a secondary criteria. This study demonstrates the presence of statistically significant prognostic subgroups within UUS, and provides treatment insights.
|
|
| 10. |
- Hardell, Elin, et al.
(author)
-
Validation of a Mitotic Index Cutoff as a Prognostic Marker in Undifferentiated Uterine Sarcomas
- 2017
-
In: American Journal of Surgical Pathology. - 0147-5185 .- 1532-0979. ; 41:9, s. 1231-1237
-
Journal article (peer-reviewed)abstract
- Undifferentiated uterine sarcomas (UUS) are a heterogenous group of high-grade mesenchymal tumors. Although these tumors are highly aggressive, a subset of patients may experience long-term survival. These tumors have previously been divided morphologically into uniform and pleomorphic types. A previous study demonstrated that a mitotic index cutoff of 25 mitoses/10 high-power fields (corresponding to 11.16 mitotic figures/mm) could successfully divide tumors into 2 prognostic groups with significantly different overall survival. The goals of the current study were to (1) validate this mitotic index cutoff in an independent, multicenter cohort and (2) explore the prognostic value of the mitotic index groups in relation to other clinicopathologic variables. Cases were included from 3 independent institutions: The Norwegian Radium Hospital, The Mayo Clinic, and Skåne University Hospital. A total of 40 tumors were included after central review. All cases were negative for the YWHAE-FAM22A/B and JAZF1-JJAZ1 translocations. Survival data were available on all patients. In this study, one-third of patients with UUS survived beyond 5 years. The crude (unadjusted) Cox Proportional Hazards model revealed a number of parameters that significantly impacted overall survival, including mitotic index group, patient age, stage, and the presence of tumor necrosis. Classification into the uniform and pleomorphic types was not prognostic. Combining these parameters into an adjusted model revealed that only the mitotic index group and stage were prognostic. On the basis of these findings, it is proposed that UUS be subdivided into “mitogenic” and “not otherwise specified” types.
|
|
