Project description:To discover potential biomarkers of melanoma development and progression, we embarked on studies comparing the glycomic gene profiles of normal human epidermal melanocytes with human metastatic melanoma (MM) cells represented by A375 and G361 cell lines. Glycomic features embody all of those enzymatic, membranous and regulatory proteins that influence glycan ‘sugar’ formation/degradation on a cell. Comparative expression profiling of glycomic genes indicated that several genes were differentially expressed between normal melanocytes and MM cells. We speculate that glycome genes differentially expressed in MM cells help drive malignant and metastatic behavior of MM cells and could potentially serve as a biomarker(s) of melanoma progression.
Project description:DNA methylation profiling of human melanocytes and melanoma cell lines. Goal was to identify hypermethylated gene promoters in melanoma Genomic DNA from 4 human melanoma cell lines and normal human epidermal melanocytes was subjected to methylated DNA immunoprecipitation (MeDIP) and hybridized to Agilent's G4489A Human Promoter ChIP-on-Chip Set 244K
Project description:To pinpoint developmental pathways that are up-regulated both in neural crest stem cells (NCSC) and in melanoma cells but not in melanocytes, we carried out computational analyses to compare gene expression profiles of human skin-derived NCSC, epidermal melanocytes and melanoma cells. Our aim was to preselect genes that exhibit high mRNA expression levels both in melanoma cells and in NCSC but low levels in melanocytes.
Project description:Early-passage (<10 passages) cultures of melanoma cells from metastatic lymph node lesions and normal adult melanocytes explanted in parallel from the adjacent, non-involved skin of 5 patients were compared by cDNA arrays. Differences between normal and neoplastic counterparts were then assessed upon adjustment for individual factors. cDNA expression profiles comparison between normal and neoplastic counterparts in a strictly autologous setting
Project description:DNA methylation is considered the primary epigenetic mechanism underlying the development of malignant melanoma. Since DNA methylation can be influenced by environmental factors, it is preferable to compare cancer and normal cells from the same patient. Here, we employed a novel epidermal sheet cultivation technique to isolate normal melanocytes from unaffected sites of melanoma patients and compared the methylation status with melanoma tissues from the same individuals. We also analyzed primary and metastatic melanoma samples, three commercially available melanocytes, and four melanoma cell lines. Cluster analysis of DNA methylation data classified freshly isolated melanomas and melanocytes into the same group, whereas the four melanoma cell lines were clustered together in a distant clade. Moreover, our analysis discovered methylation at several novel loci (KRTCAP3, AGAP2, ZNF490), in addition to those identified in previous studies (COL1A2, GPX3); however, the latter two were not observed in fresh melanoma samples. Subsequent studies revealed that NPM2 was hypermethylated and downregulated in melanomas, which was consistent with previous reports and indicated that NPM2 immunoreactivity could be used to differentiate melanomas from normal melanocytes or benign disease. Our results highlight the importance of using matched fresh melanoma and melanocyte samples in epigenetic studies. Illumina Infinium 450k Human Methylation Beadchip
Project description:The study aims to identify differences in miRNA expression during melanoma development. Therefore, normal human epidermal melanocytes (NHEM) were de-differentiated into melanoblast-related cells (MBrCs) to model processes during embryonic differentiation and to compare them to the tumorigenic phenotype in melanoma development.
Project description:Development of melanoma brain metastasis is caused by an interaction between tumor cells and normal cells in the brain microenvironment. miRNAs delivered by exosomes derived from the tumor cells seem to prime the brain microenvironment, prior to extravasation of tumor cells into the brain. We investigated miRNA in exosomes extracted from normal (astrocytes, melanocytes) and metastatic melanoma cells (brain, skin and lymph node metastasis). We have discovered that miR-146a-5p is an important player in brain metastatic development: this miRNA was highly upregulated in exosomes from melanoma brain metastasis cells, compared to normal cells.
