GSE60664
Decoding the regulatory landscape of melanoma reveals TEADS as regulators of the invasive cell state.
Understanding the molecular processes underlying intra-tumor heterogeneity is of critical importance to improve the efficiency of therapy and overcome drug resistance. In malignant melanoma, heterogeneity is though to arise -at least partly- through epigenetic rather than genetic reprogramming of proliferating cells, leading to the appearance within the primary tumors of a phenotypically distinct invasive cell subpopulation. The invasive melanoma cells are at the origin of metastatic spread and are thought to provide a reservoir of therapeutically resistant cells. To decipher the gene regulatory networks that underlie the proliferative and invasive cellular states we integrated publicly available gene expression and DNA methylation data from tumor biopsies with a newly generated compendium of open chromatin and histone modification profiling of melanoma cultures that are dominant in either of the two subpopulations. Extensive in silico analyses identified SOX10 and MITF, and AP-1 and TEADs as key upstream regulators of the proliferative and invasive transcriptomes, respectively. Knock-down experiments confirmed the implication of TEADs in the invasive gene network and, more importantly, established a causative link between activation of these transcription factors and melanoma cell invasion and sensitivity to MAPK inhibitors. Overall design: Investigation of the transcriptomes of 11 different melanoma cultures & Investigation of the effects of the Knock down of all 4 TEADs in an invasive melanoma culture (MM047).