In this study, we demonstrated that CD49f+/ERα + prostate cancer cells associated with basal stem-like and EMT features (EMT-PCBSLCs), as having elevated potential for metastasis, NOTCH1 may be an essential E2-regulated gene pivotal to driving CD49fHi EMT-PCBSLCs subpopulations. The gene discussed is NOTCH1; the disease is prostate cancer.