ALDH1A1 and ductal breast carcinoma in situ: The stem-cell factors sex-determining region Y-related high-mobility group box 9 (SOX9) and aldehyde dehydrogenase 1 (ALDH1), the most activated factors in ductal carcinoma in situ (DCIS) stem-like cells, were identified to be objective targets for miR-140 [102].