ALDH1A1 and ovarian cancer: Comparing the expression between ALDH1A1 and ALDH2, stronger ALDH2 expression can be found in the tumor stem-like cells of atypical teratoid/rhabdoid tumour (TSC-AT/RT), and in both parental and stem-like tumor cells of breast cancer, prostate cancer, ovarian cancer and glioblastoma (GBM).