Project description:Melanoma cell lines were genotyped to evaluate copy number differences between nodular melanoma (NM) and superficial spreading melanoma (SSM). Cell lines were also evaluated for copy number alterations in the SKP2/p27 axis. Affymetrix SNP arrays were performed according to manufacturer's instructions using DNA extracted from 18 melanoma cell lines and 4 melanocyte controls. Affymetrix SNP6.0 Array data for melanoma cell lines Copy number analysis of Affymetrix SNP 6.0 arrays was performed on 18 melanoma cell lines including 2 primary superficial spreading melanoma, 2 primary nodular melanoma, 2 metastatic nodular melanoma, and 12 metastatic cell lines. Four melanocyte control lines were also evaluated including 2 immortalized melanocyte cell lines (Hermes 1 and 2B) and 2 normal melanocyte lines cultured from neonatal foreskin (HEM-N and HEM-LP) that were used to construct the baseline for copy number analysis.
Project description:We investigated the miRNAome in human melanocyte and melanoma cell lines using high-throughput RNA sequencing. We identified a group of dysregulated miRNAs by comparing the miRNA expression profiles among melanoma cell lines. Target genes of these miRNAs participate in functions associated with the cell cycle and apoptosis. Gene networks were built to investigate the interactions of genes during melanoma progression. We identified that the key genes that regulate melanoma cell proliferation were regulated by miRNAs. Our findings provide further knowledge regarding the mechanisms of melanoma development. miRNA profiles of melanocyte (HEMn-LP), low metastatic melanoma (A375) and high metastatic melanoma (A2058) cell line were generated using Illumina GA
Project description:Although mutations in p53 are infrequent in human melanoma, its function is abnormal. In this study, whole genome bead arrays were used to examine the expression of p53 target genes in extracts from 82 metastatic melanoma samples, compared to extracts derived from diploid human melanocytes, to provide a global assessment of aberrant p53 function. Total RNA extracted from 82 tumour samples and 8 melanocyte cell lines was analysed. Metastatic melanomas were compared to melanocyte cell lines.
Project description:Although mutations in p53 are infrequent in human melanoma, its function is abnormal. In this study, whole genome bead arrays were used to examine the expression of p53 target genes in extracts from 6 melanoma cell lines, compared to extracts derived from diploid human melanocytes and fibroblasts, to provide a global assessment of aberrant p53 function. The expression of these genes was also examined in extracts derived from melanocytes and melanoma cell lines in which p53 expression had been inhibited using shRNA and compared to cells that had been transduced with a control shRNA. Total RNA extracted from 18 samples was analysed representing duplicates of 6 melanoma cell lines, 1 melanocyte cell line and 2 fibroblast cell lines. Melanoma cell lines were compared to normal cell lines. In addition, IgR3, Mel-RM and melanocyte cell lines were transduced with either control shRNA or p53 shRNA to evaluate the effect of p53 on its target genes. Cell lines transduced with control shRNA were compared to cell lines transduced with p53shRNA. Duplicates were analysed.
Project description:The two most common melanoma histopathologic subtypes, superficial spreading (SSM) and nodular melanoma (NM), are believed to represent sequential phases of linear progression from radial to vertical growth. Studies suggest, however, that SSM and NM are biologically distinct. We utilized an integrative genomic approach to examine the possibility that SSM and NM are the result of independent pathways characterized by unique molecular alterations. Cell lines including SSM, NM, metastatic melanoma, and melanocyte controls were evaluated for copy number changes and differential mRNA expression using single nucleotide polymorphism array (SNP 6.0, Affymetrix) and gene array (U133A 2.0, Affymetrix). Data sets were integrated to identify copy number alterations that correlated with gene expression, and array results were validated using immunohistochemistry on human tissue microarrays (TMAs) and an external data set. The functional effect of genomic deletion was assessed by lentiviral overexpression. Integrative genomics revealed 8 genes in which NM/SSM-specific copy number alterations were correlated with NM/SSM differential gene expression (P<0.05, Spearman’s rank). Pathways analysis of differentially expressed genes (N=114) showed enrichment for metabolic-related processes. SSM-specific genomic deletions (DIS3, MTAP, G3BP2, SEC23IP, USO1) were verified in an expanded panel of cell lines, and forced overexpression of MTAP in SSM resulted in reduced cell growth. Metabolism-related gene ALDH7A1 was verified as overexpressed in NM using human TMAs.The identification of recurrent genomic deletions in SSM not present in NM challenges the linear model of melanoma progression and supports the unique molecular classification of SSM and NM. Gene expression profiling using Affymetrix U133A 2.0 arrays was performed on 18 melanoma cell lines including 2 primary superficial spreading melanoma, 2 primary nodular melanoma, 2 metastatic nodular melanoma, and 12 metastatic cell lines. Four melanocyte control lines were also evaluated including 2 immortalized melanocyte cell lines (Hermes 1 and 2B) and 2 normal melanocyte lines cultured from neonatal foreskin (HEM-N and HEM-LP).