PAQR8 and breast cancer: Ironically, contrary to their nomenclature, the majority of PAQR8 resides in the nucleus initially, and remains localized primarily to the nucleus throughout the experiment (Supplementary Figure S3C), suggesting a dominant nuclear localization of mPRs in nPR(−) RBMVECs under mPR-specific PRG actions, validating our previous observations in nPR(+/−) breast cancer cells [6,7,8].