Mutational landscape of MCPyV-positive and MCPyV-negative Merkel cell carcinomas
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA750166 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Mutational landscape of MCPyV-positive and MCPyV-negative Merkel cell carcinomas
| PRJNA750167 | ENA
Project description:Merkel cell carcinoma (MCC) is a rare but highly aggressive cutaneous neuroendocrine carcinoma, associated with the Merkel cell polyomavirus (MCPyV) in 80% of cases. To define the genetic basis of MCCs, we performed exome sequencing of 49 MCCs. We show that MCPyV-negative MCCs have a high mutation burden (median of 1121 somatic single nucleotide variants (SSNVs) per-exome with frequent mutations in RB1 and TP53 and additional damaging mutations in genes in the chromatin modification (ASXL1, MLL2, and MLL3), JNK (MAP3K1 and TRAF7), and DNA-damage pathways (ATM, MSH2, and BRCA1). In contrast, MCPyV-positive MCCs harbor few SSNVs (median of 12.5 SSNVs/tumor) with none in the genes listed above. In both subgroups, there are rare cancer-promoting mutations predicted to activate the PI3K pathway (HRAS, KRAS, PIK3CA, PTEN, and TSC1) and to inactivate the Notch pathway (Notch1 and Notch2). TP53 mutations appear to be clinically relevant in virus-negative MCCs as 37% of these tumors harbor potentially targetable gain-of-function mutations in TP53 at p.R248 and p.P278. Moreover, TP53 mutational status predicts death in early stage MCC (5-year survival in TP53 mutant vs wild-type stage I and II MCCs is 20% vs. 92%, respectively; P = 0.0036). Lastly, we identified the tumor neoantigens in MCPyV-negative and MCPyV-positive MCCs. We found that virus-negative MCCs harbor more tumor neoantigens than melanomas or non-small cell lung cancers (median of 173, 65, and 111 neoantigens/sample, respectively), two cancers for which immune checkpoint blockade can produce durable clinical responses. Collectively, these data support the use of immunotherapies for virus-negative MCCs.
| S-EPMC4823115 | biostudies-literature
Project description:Merkel cell carcinoma (MCC) is an aggressive cutaneous neuroendocrine tumor with high mortality rates. Merkel cell polyomavirus (MCPyV), identified in the majority of MCC, may drive tumorigenesis via viral T antigens. However, mechanisms underlying pathogenesis in MCPyV-negative MCC remain poorly understood. To nominate genes contributing to pathogenesis of MCPyV-negative MCC, we performed DNA microarray analysis on 30 MCCs. MCPyV status of MCCs was determined by PCR for viral DNA and RNA. 1593 probe-sets were differentially expressed between MCPyV-negative and -positive MCC, with significant differential expression defined as at least 2-fold change in either direction and p-value of ≤ 0.05. MCPyV-negative tumors showed decreased RB1 expression, whereas MCPyV-positive tumors were enriched for immune response genes. Validation studies included immunohistochemistry demonstration of decreased RB protein expression in MCPyV-negative tumors and increased peritumoral CD8+ T lymphocytes surrounding MCPyV-positive tumors. In conclusion, our data suggest that loss of RB1 expression may play an important role in tumorigenesis of MCPyV-negative MCC. Functional and clinical validation studies are needed to determine whether this tumor suppressor pathway represents an avenue for targeted therapy. We used microarrays to characterize global gene expression patterns related to Merkel cell polyomavirus status in Merkel cell carcinoma. Furthermore, we compared Merkel cell carcinoma to less aggressive primary cutaneous carcinomas. We utilized flash-frozen tumor tissue from primary Merkel cell carcinomas, metastatic Merkel cell carcinomas, primary cutaneous squamous cell carcinomas, and basal cell carcinomas. Merkel cell carcinoma cell lines, which represent a pure population of tumor cells, were also included. Merkel cell polyomavirus status was determined at the DNA and RNA level using multiple primers for viral T-antigen and capsid protein sequences. This Series represents two analyses - one with new Samples normalized together, and another with some of the new Samples re-normalized with Samples previously submitted under Series GSE13355. The latter group contain 'renormalized' in the titles.
2012-10-18 | E-GEOD-39612 | biostudies-arrayexpress
Project description:Merkel cell carcinoma is supposed to be derived from Merkel cells after infection by Merkel cell polyomavirus (MCPyV) and other poorly known events. A transcriptional profiling with cDNA microarrays was performed on cells from MCPyV(+) Merkel cell carcinomas and isolated normal Merkel cells. This microarray revealed numerous significantly upregulated genes and downregulated genes. The extensive list of genes identified in these experiments provides a large body of potentially valuable information of Merkel cell carcinoma carcinogenesis and could represent a source of potential targets for cancer therapy.
2014-01-01 | GSE50434 | GEO
Project description:Merkel cells are epidermal mechanoreceptor cells responsible for the perception of gentle touch. Merkel cell carcinoma (MCC) is a rare and highly aggressive skin cancer. Although MCC histologically resembles Merkel cells, the cell of origin for MCC is unknown. MCC frequently contains integrated Merkel cell polyomavirus (MCPyV), a small DNA tumor virus with widespread prevalence. Whether MCPyV can transform Merkel cells is unknown. Here, we describe the isolation and long-term expansion of human Merkel cells from neonatal foreskin. We validated the expression of several Merkel cell-related factors by RNASeq, and assessed the ultrastructure by electron microscopy. Culture of Merkel cell preparations on an artificial basement membrane promoted the formation of structures containing both Merkel and non-Merkel cell populations. To determine whether Merkel cells were susceptible to transformation, we expressed tumor-derived MCPyV T antigens and additional oncogenes. We were unable to demonstrate tumorigenesis in immunodeficient mice, but were able to detect T antigen expression from excised cells weeks after implantation. These results highlight that foreskin-isolated Merkel cells can be propagated extensively, sustain expression of MCPyV T antigens, but are not susceptible to transformation by MCPyV, suggesting that Merkel cells from non-glabrous skin may not be a cell of origin for MCC.
2017-04-01 | GSE79657 | GEO
Project description:Merkel cell polyomavirus (MCPyV) is the first human polyomavirus etiologically associated with Merkel cell carcinoma (MCC), a rare and aggressive form of skin cancer. Similar to other polyomaviruses, MCPyV encodes early T antigen genes, a viral oncogene required for MCC tumor growth. To identify the unique oncogenic properties of MCPyV, we analysed the gene expression profiles in human spontaneously immortalized keratinocytes (NIKs) expressing the early genes from five distinct human polyomaviruses (PyVs), including MCPyV. A comparison of the gene expression profiles revealed 28 genes specifically deregulated by MCPyV.
2019-09-13 | GSE137328 | GEO
Project description:Merkel cell carcinoma (MCC) is an aggressive cutaneous neuroendocrine tumor with high mortality rates. Merkel cell polyomavirus (MCPyV), identified in the majority of MCC, may drive tumorigenesis via viral T antigens. However, mechanisms underlying pathogenesis in MCPyV-negative MCC remain poorly understood. To nominate genes contributing to pathogenesis of MCPyV-negative MCC, we performed DNA microarray analysis on 30 MCCs. MCPyV status of MCCs was determined by PCR for viral DNA and RNA. 1593 probe-sets were differentially expressed between MCPyV-negative and -positive MCC, with significant differential expression defined as at least 2-fold change in either direction and p-value of ≤ 0.05. MCPyV-negative tumors showed decreased RB1 expression, whereas MCPyV-positive tumors were enriched for immune response genes. Validation studies included immunohistochemistry demonstration of decreased RB protein expression in MCPyV-negative tumors and increased peritumoral CD8+ T lymphocytes surrounding MCPyV-positive tumors. In conclusion, our data suggest that loss of RB1 expression may play an important role in tumorigenesis of MCPyV-negative MCC. Functional and clinical validation studies are needed to determine whether this tumor suppressor pathway represents an avenue for targeted therapy. We used microarrays to characterize global gene expression patterns related to Merkel cell polyomavirus status in Merkel cell carcinoma. Furthermore, we compared Merkel cell carcinoma to less aggressive primary cutaneous carcinomas.
2012-10-18 | GSE39612 | GEO
Project description:Bulk RNA sequencing of MCPyV positive and negative patient derived Merkel cell carcinoma cell lines
| PRJNA925504 | ENA
Project description:Merkel cell carcinoma is supposed to be derived from Merkel cells after infection by Merkel cell polyomavirus (MCV) and other poorly known events. A transcriptional profiling with cDNA microarrays was performed on cells from MCV+ Merkel cell carcinomas and isolated normal Merkel cells. This microarray revealed numerous significantly upregulated genes and down-regulated genes. The extensive list of genes identified in these experiments provides a large body of potentially valuable information of Merkel cell carcinoma carcinogenesis and could represent a source of potential targets for cancer therapy. Two-conditions experiment, MCV vs Normal Merkel Cell. Biological replicates : 4 MCV (Cy5), 1 control = pool of Normal Merkel cells from 3 liftings
2014-01-01 | E-GEOD-50434 | biostudies-arrayexpress
Project description:Merkel cell polyomavirus (MCPyV) is linked to Merkel cell carcinoma (MCC), a rare and aggressive skin cancer. This study investigated the influence of MCPyV T antigens on the host genome using transcriptomics and epigenomics. Results revealed a role for the small Tumor (sT) antigen in subverting type I interferon response and immune evasion, contributing to persistent infection and tumor progression. These findings enhance our understanding of MCPyV pathogenesis and may inform new therapeutic strategies.
2024-04-04 | GSE230758 | GEO