Notably, inhibition of ALDH1A1 has been shown to sensitize ALDH1A1-enriched pancreatic cancer MIA PaCa-2 cells to gemcitabine (20); in addition, inhibition of ALDH has been also shown to sensitize ALDH-enriched ovarian and breast cancer cells to chemotherapy and radiotherapy (18,47). Here, ALDH1A1 is linked to breast cancer.