Project description:Epigenetic alterations play significant roles in the melanoma tumorigenesis and malignant progression. We profiled genome-wide promoter DNA methylation patterns of melanoma cells deribed from primary lesions of Radial Growrth phase (RGP) and Vertical Growth Phase (VGP), metastatic lesions, and primary normal melanocytes by interrogating 14,495 genes using Illumina bead chip technology. By comparative analysis of the promoter methylation profiles, we identified epigenetically silenced gene signatures that potentially associated with malignant melanoma progression. Bisulphite converted genomic DNA from a group of melanoma cells representing pathologic stages of melanoma progression (3 cell lines derived from RGP melanoma lesions, 4 cell lines derived from VGP lesions, and 3 melastatic melanomas) and normal human primary melanocytes isolated from lightly pigmented adult skin were hybridized to Illumina's Infinium HumanMethylation27 BeadChips
Project description:Epigenetic alterations play significant roles in the melanoma tumorigenesis and malignant progression. We profiled genome-wide promoter DNA methylation patterns of melanoma cells deribed from primary lesions of Radial Growrth phase (RGP) and Vertical Growth Phase (VGP), metastatic lesions, and primary normal melanocytes by interrogating 14,495 genes using Illumina bead chip technology. By comparative analysis of the promoter methylation profiles, we identified epigenetically silenced gene signatures that potentially associated with malignant melanoma progression.
Project description:The imbalance of cellular homeostasis during oncogenesis together with the high heterogeneity of tumor-associated stromal cells have a marked effect on the repertoire of the proteins secreted by malignant cells (the secretome). Hence, the study of tumoral secretomes provides insights for understanding the cross-talk between cells within the tumor microenvironment as well as the key effectors for the establishment of the pre-metastatic niche in distant tumor sites. In this context, we performed a proteomic analysis of the secretomes derived from four cell lines: (i) a paired set of fibroblasts - Hs 895. T, a cell line obtained from a lung node metastatic site from a patient who had melanoma and Hs 895.Sk, a skin fibroblast cell line (derived from the same patient); (ii) two malignant metastatic melanoma cell lines - A375, a malignant melanoma cell line from primary source and SH-4, a cell line derived from pleural effusion of a patient with metastatic melanoma. Clustering of expression profiles together with functional enrichment revealed patterns that mirrored each cell type (skin fibroblasts, cancer-associated fibroblasts and metastatic cells). These patterns might be the result of cell-specific protein expression programs and may serve as basis for further proteomic analysis of melanoma cell lines secretomes.
Project description:Reactive oxygen species (ROS) are implicated in tumor transformation by modulating proteins involved in differentiation, proliferation and invasion. In order to identify genes that may support melanoma progression or regression after an antioxidant system (AOS) response, we developed and characterized a human melanoma cell model with different levels of ROS by stably overexpressing the antioxidant enzyme catalase in A375 amelanotic melanoma cells, and whole genome gene expression patterns were analyzed by microarrays. We used gene expression microarrays to study the AOS global response to catalase overexpression and to identify up-regulated and down-regulated genes during progression or regression of melanoma.
Project description:Analysis of gene expression patterns in cancer improved the understanding the mechanisms underlying the process of metastatic progression. Recent studies have attributed an important role to B-1 cells, a subset of B lymphocytes, in melanoma progression. It was already demonstrated that in vitro interaction between B16 melanoma cells and B-1 lymphocytes induced increase in metastatic potential of B16 lineage. In this study we used a microarray approach to assess gene expression profile in B16 melanoma cells after contacting B-1 lymphocytes (B16B1).