Previous evidence showed that miR-142-3p functions to suppress both tumorigenesis and the generation of cancer stem cells in triple-negative breast cancer [31,32], where overexpression of miR-142-3p was shown to reduce breast cancer stem cell characteristics and was associated with decreased expressions of CD44, CD133, ALDH1, Bod1, and BRCA2, and lower mammosphere formation while increasing sensitivity to radiation [31]. This evidence concerns the gene ALDH1A1 and cancer.