BACKGROUNDS: SWI/SNF complexes represent a family of multi-subunit chromatin remodelers that are affected by alterations in >20% of human tumors. While mutations of SWI/SNF genes are relatively uncommon in prostate cancer (PCa), the literature suggests that deregulation of various subunits plays a role in prostate tumorigenesis. To assess SWI/SNF functions in a clinical context, we studied the mutually exclusive, paralogue accessory subunits SMARCD1, SMARCD2, and SMARCD3 that are included in every known complex and are sought to confer specificity. METHODS: Performing immunohistochemistry (IHC), the protein levels of the SMARCD family members were measured using a tissue microarray (TMA) comprising malignant samples and matching healthy tissue of non-metastatic PCa patients (n = 168). Moreover, IHC was performed in castration-resistant tumors (n = 9) and lymph node metastases (n = 22). To assess their potential role as molecular biomarkers, SMARCD1 and SMARCD3 protein levels were correlated with clinical parameters such as T stage, Gleason score, biochemical recurrence, and progression-free survival. RESULTS: SMARCD1 protein levels in non-metastatic primary tumors, lymph node metastases, and castration-resistant samples were significantly higher than in benign tissues. Likewise, SMARCD3 protein expression was elevated in tumor tissue and especially lymph node metastases compared to benign samples. While SMARCD1 levels in primary tumors did not exhibit significant associations with any of the tested clinical parameters, SMARCD3 exhibited an inverse correlation with pre-operative PSA levels. Moreover, low SMARCD3 expression was associated with progression to metastasis. CONCLUSIONS: In congruence with previous literature, our results implicate that both SMARCD1 and SMARCD3 may exhibit relevant functions in the context of prostate tumorigenesis. Moreover, our approach suggests a potential role of SMARCD3 as a novel prognostic marker in clinically non-metastatic PCa.

• Klíčová slova
• SMARCD1, SMARCD3, SWI/SNF complex, prognostic marker, prostate cancer,
• MeSH
• chromozomální proteiny, nehistonové * genetika   metabolismus   MeSH
• imunohistochemie MeSH
• lidé středního věku MeSH
• lidé MeSH
• lokální recidiva nádoru patologie   metabolismus   genetika   MeSH
• lymfatické metastázy MeSH
• nádorové biomarkery * genetika   metabolismus   MeSH
• nádory prostaty rezistentní na kastraci patologie   genetika   metabolismus   MeSH
• nádory prostaty * patologie   metabolismus   genetika   MeSH
• prognóza MeSH
• senioři MeSH
• stupeň nádoru MeSH
• transkripční faktory genetika   metabolismus   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chromozomální proteiny, nehistonové * MeSH
• nádorové biomarkery * MeSH
• SMARCD1 protein, human MeSH Prohlížeč
• transkripční faktory MeSH

Previous studies have demonstrated an involvement of chromatin-remodelling SWI/SNF complexes in the development of prostate cancer, suggesting both tumor suppressor and oncogenic activities. SMARCD1/BAF60A, SMARCD2/BAF60B, and SMARCD3/BAF60C are mutually exclusive accessory subunits that confer functional specificity and are components of all known SWI/SNF subtypes. To assess the role of SWI/SNF in prostate tumorigenesis, we studied the functions and functional relations of the SMARCD family members. Performing RNA-seq in LnCAP cells grown in the presence or absence of dihydrotestosterone, we found that the SMARCD proteins are involved in the regulation of numerous hormone-dependent AR-driven genes. Moreover, we demonstrated that all SMARCD proteins can regulate AR-downstream targets in androgen-depleted cells, suggesting an involvement in the progression to castration-resistance. However, our approach also revealed a regulatory role for SMARCD proteins through antagonization of AR-signalling. We further demonstrated that the SMARCD proteins are involved in several important cellular processes such as the maintenance of cellular morphology and cytokinesis. Taken together, our findings suggest that the SMARCD proteins play an important, yet paradoxical, role in prostate carcinogenesis. Our approach also unmasked the complex interplay of paralogue SWI/SNF proteins that must be considered for the development of safe and efficient therapies targeting SWI/SNF.

• Klíčová slova
• SMARCD1/BAF60A, SMARCD2/BAF60B, SMARCD3/BAF60C, SWI/SNF complex, chromatin-remodeling, prostate cancer,
• MeSH
• androgenní receptory * genetika   metabolismus   MeSH
• chromozomální proteiny, nehistonové genetika   metabolismus   MeSH
• lidé MeSH
• nádory prostaty * genetika   MeSH
• regulace genové exprese MeSH
• restrukturace chromatinu genetika   MeSH
• signální transdukce MeSH
• transkripční faktory metabolismus   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• androgenní receptory * MeSH
• chromozomální proteiny, nehistonové MeSH
• SMARCD1 protein, human MeSH Prohlížeč
• transkripční faktory MeSH

Small cell carcinoma of hypercalcemic type (SCCOHT) is a rare gynaecological neoplasm, originating mostly in the ovaries. Cervical origin of this very aggressive malignancy with unknown histogenesis is an extremely rare condition, without published management recommendations. Alterations in SMARCA4 gene are supposed to play the major role in SCCOHT oncogenesis and their identification is crucial for the diagnosis. Adequate genetic counselling of the patients and their families seems to be of great importance. Optimal management and treatment approaches are not known yet but may extremely influence the prognosis of young female patients that suffer from this very resistant disease. Nowadays, a translational research seems to be the key for the further diagnostic and treatment strategies of SCCOHT. The purpose of the case report is to provide practical information and useful recommendations on the diagnosis, management, and treatment of SMARCA4-deficient carcinoma of the uterine cervix resembling SCCOHT.

• Klíčová slova
• case report, cervical cancer, diagnostic biomarker, gynecological cancer, high-risk, personalized treatment, predictive marker,
• MeSH
• DNA-helikasy nedostatek   genetika   MeSH
• fatální výsledek MeSH
• hyperkalcemie diagnóza   genetika   metabolismus   terapie   MeSH
• jaderné proteiny nedostatek   genetika   MeSH
• lidé MeSH
• malobuněčný karcinom diagnóza   genetika   metabolismus   terapie   MeSH
• mladiství MeSH
• mutace MeSH
• nádorové biomarkery nedostatek   genetika   MeSH
• nádory děložního čípku diagnóza   genetika   metabolismus   terapie   MeSH
• transkripční faktory nedostatek   genetika   MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Názvy látek
• DNA-helikasy MeSH
• jaderné proteiny MeSH
• nádorové biomarkery MeSH
• SMARCA4 protein, human MeSH Prohlížeč
• transkripční faktory MeSH

Mutation of SMARCA4 (BRG1), the ATPase of BAF (mSWI/SNF) and PBAF complexes, contributes to a range of malignancies and neurologic disorders. Unfortunately, the effects of SMARCA4 missense mutations have remained uncertain. Here we show that SMARCA4 cancer missense mutations target conserved ATPase surfaces and disrupt the mechanochemical cycle of remodeling. We find that heterozygous expression of mutants alters the open chromatin landscape at thousands of sites across the genome. Loss of DNA accessibility does not directly overlap with Polycomb accumulation, but is enriched in 'A compartments' at active enhancers, which lose H3K27ac but not H3K4me1. Affected positions include hundreds of sites identified as superenhancers in many tissues. Dominant-negative mutation induces pro-oncogenic expression changes, including increased expression of Myc and its target genes. Together, our data suggest that disruption of enhancer accessibility represents a key source of altered function in disorders with SMARCA4 mutations in a wide variety of tissues.

• MeSH
• adenosintrifosfatasy metabolismus   MeSH
• chromatin chemie   MeSH
• DNA-helikasy genetika   MeSH
• dominantní geny * MeSH
• epigenomika MeSH
• genotyp MeSH
• heterozygot MeSH
• jaderné proteiny genetika   MeSH
• kultivační média MeSH
• lidé MeSH
• missense mutace MeSH
• multivariační analýza MeSH
• mutace * MeSH
• myší embryonální kmenové buňky cytologie   MeSH
• myši transgenní MeSH
• myši MeSH
• nádory genetika   MeSH
• polycomb proteiny genetika   MeSH
• restrukturace chromatinu MeSH
• sekvenční analýza RNA MeSH
• transkripční faktory genetika   MeSH
• zesilovače transkripce MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• adenosintrifosfatasy MeSH
• chromatin MeSH
• DNA-helikasy MeSH
• jaderné proteiny MeSH
• kultivační média MeSH
• polycomb proteiny MeSH
• SMARCA4 protein, human MeSH Prohlížeč
• transkripční faktory MeSH

The information on candidate cancer driver alterations available from public databases is often descriptive and of limited mechanistic insight, which poses difficulties for reliable distinction between true driver and passenger events. To address this challenge, we performed in-depth analysis of whole-exome sequencing data from cell lines generated by a barrier bypass-clonal expansion (BBCE) protocol. The employed strategy is based on carcinogen-driven immortalization of primary mouse embryonic fibroblasts and recapitulates early steps of cell transformation. Among the mutated genes were almost 200 COSMIC Cancer Gene Census genes, many of which were recurrently affected in the set of 25 immortalized cell lines. The alterations affected pathways regulating DNA damage response and repair, transcription and chromatin structure, cell cycle and cell death, as well as developmental pathways. The functional impact of the mutations was strongly supported by the manifestation of several known cancer hotspot mutations among the identified alterations. We identified a new set of genes encoding subunits of the BAF chromatin remodeling complex that exhibited Ras-mediated dependence on PRC2 histone methyltransferase activity, a finding that is similar to what has been observed for other BAF subunits in cancer cells. Among the affected BAF complex subunits, we determined Smarcd2 and Smarcc1 as putative driver candidates not yet fully identified by large-scale cancer genome sequencing projects. In addition, Ep400 displayed characteristics of a driver gene in that it showed a mutually exclusive mutation pattern when compared with mutations in the Trrap subunit of the TIP60 complex, both in the cell line panel and in a human tumor data set. We propose that the information generated by deep sequencing of the BBCE cell lines coupled with phenotypic analysis of the mutant cells can yield mechanistic insights into driver events relevant to human cancer development.

• MeSH
• exom genetika   MeSH
• fibroblasty MeSH
• lidé MeSH
• mutace MeSH
• myši MeSH
• nádorová transformace buněk genetika   MeSH
• nádorové proteiny genetika   MeSH
• nádory genetika   MeSH
• primární buněčná kultura MeSH
• vysoce účinné nukleotidové sekvenování * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• nádorové proteiny MeSH