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
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.
Project description:MicroRNAs have been implicated in various skin cancers, including melanoma, squamous cell carcinoma, and basal cell carcinoma; however, the expression of microRNAs and their role in Merkel cell carcinoma (MCC) have yet to be explored in depth. To identify microRNAs specific to MCC (MCC-miRs), next-generation sequencing (NGS) of small RNA libraries was performed on different tissue samples including MCCs, other cutaneous tumors, and normal skin. Comparison of the profiles identified several microRNAs upregulated and downregulated in MCC. For validation, their expression was measured via qRT-PCR in a larger group of MCC and in a comparison group of non-MCC cutaneous tumors and normal skin. Eight microRNAs were upregulated in MCC: miR-502-3p, miR-9, miR-7, miR-340, miR-182, miR-190b, miR-873, and miR-183. Three microRNAs were downregulated: miR-3170, miR-125b, and miR-374c. Many of these MCC-miRs, with the miR-183/182/96a cistron in particular, have connections to tumorigenic pathways implicated in MCC pathogenesis. In situ hybridization confirmed that the highly expressed MCC-miR, miR-182, is localized within tumor cells. Furthermore, NGS and qRT-PCR reveals that several of these MCC-miRs are highly expressed in the patient-derived MCC cell line, MS-1. These data indicate that we have identified a set of MCC-miRs with high implications for MCC research. To identify microRNAs specific to Merkel cell carcinoma (MCC) next-generation sequencing (NGS) of small RNA libraries was performed on different tissue samples including MCCs, other cutaneous tumors, and normal skin
Project description:We performed miRNA expression profiling in a series of human Merkel Cell carcinoma samples using a microarray approach. Significant differentially expressed miRNAs among groups were identified using SAM analysis. Agilent microarray platform containing 723 human miRNAs was used to determine miRNA expression profiles in 16 human Merkel cell carcinoma (MCC) samples. To validate the microarray platform, the expression levels of selected miRNAs were evaluated using qRT-PCR.
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.
Project description:Array-CGH profiles of Merkel cell carcinoma tumors Experiment Overall Design: We perfromed array-CGH on 25 Merkel cell carcinoma tumor samples (2 primary/metastasis pairs) looking for recurrent gains/losses among the cohort of tumors. Experiment Overall Design: Results from the Analysis of Copy Errors (ACE) may be found in GSE13239_MccACEAnalyzedData.txt. Experiment Overall Design: The overall profiles of the primary/metastasis pairs are similar. These metastases samples, 1m and 3m, were excluded from the ACE analysis.
Project description:Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine tumor of the skin with growing incidence. In research immortalized cell lines are used for in vitro experiments in order to better understand the biology of this malignant disease.
Project description:We performed miRNA expression profiling in a series of human Merkel Cell carcinoma samples using a microarray approach. Significant differentially expressed miRNAs among groups were identified using SAM analysis.