Project description:To improve our understanding of the relationships between methylation and expression we profiled mRNA expression and single-base resolution methylation levels for two breast cancer cell lines, MCF7 and T47D. Expression was profiled using RNA-seq. Methylation was assayed using Methyl-MAPS, which uses methylation-sensitive and -dependent restriction enzyme digests followed by high-throughput sequencing to identify methylation levels at individual CpGs (Edwards et al. 2010, Genome Research). DNA Methylation was assayed for two breast cancer cell lines using Methyl-MAPS.
Project description:To evaluate the methylation profiles of breast cell lines, we performed methylation profiling of 55 well-characterized breast cancer cell lines on the Illumina HumanMethylation27 (HM27) platform and made use of publicly available methylation profiles of primary breast tumors for comparison. The available annotation for each cell line includes estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status, as well as the tumor type, and the age of each patient. Additionally, recent publications have described genome-wide mRNA expression profiles for most of these lines, and samples were classified on the basis of the expression profile into Basal A (BaA), Basal B/Claudin Low (BaB/CLDNlow) and Luminal (Lu) subtypes. Finally, GI50 has been calculated for these cell lines for 77 approved therapeutic agents. We find that the DNA methylation profiles of breast cancer cell lines largely retain the features that characterize primary tumors, although there are crucial differences as well. We assayed DNA methylation in 55 breast cancer cell lines. DNA extracted from breast cell lines was bisulfite treated and hybridized to Illumina HM27 arrays.