RNA-seq of T47D and MDA-MB-134 cell lines with normal or reduced ability to respond to progesterone

In order to study the role of progesterone receptor (PR) in the context of estrogen receptor positive (ER+) breast cancer, we performed RNA-seq of T47D (ER+/PR+) and MDA-MB-134 (ER+/PR-) cell lines. We disrupted the PR gene in T47D cells using the CRISPR/Cas9 technology and obtained cell pools we termed PR-low as progesterone (P4) mediated effects were inhibited or blocked. Moreover we transiently transfected MDA-MB-134 cells with a PR-B encoding plasmid (pSG5-PRB). We analyzed the gene expression profiles of T47D PR-low and T47D control pools as well as MDA-MB-134 control and transfected cells in the absence of hormone and upon treatment with P4 alone or with P4 and estrogen together. The present study provides new insights into the highly diverse and central role of PR in ERa-positive/PR-positive breast cancer cells.