DNA methylation signature defines genes modulated by stromal cell contents of human breast tumors [MethylationEPIC]

Using genome-wide approaches we have identified groups of genes modulated by CAF-secreted factors from human breast cancer cell lines grown in different CAF-conditioned medium. The genes modulated by CAF secreted factors were characterized by a specific DNA methylation pattern: hypermethylation at transcription start site (TSS) and shore regions. Approximately 60% of them exhibited a methylation-dependent expression level and 20% of them were also dependent on the methyl-CpG-binding protein domain 2. Thus, these specific DNA methylation patterns were linked to an epigenetic control of their expression, upon CAF-secreted factors. We have therefore identified some molecular events defining the responsiveness of groups of genes to stromal cell contents in human breast tumors. SBR3 and AU565 cell lines none treated or treated with CAF-conditionned medium or with Decitabine in duplicate