ALDH1A3 and neoplasm: ALDH1A3 is the primary contributor of the Aldefluorhigh activity that defines the CSCs of multiple cancers, is associated with poor prognosis, actively promotes tumor growth, invasion, and metastasis, contributes to chemoresistance in multiple cancers, and has been proposed as a therapeutic target [23, 25, 27–31, 36, 61–70].