ALDH2 and breast cancer: To evaluate ALDH, in particular ALDH1A3, as potential target in CSC maintenance, we tested the effect of multiple ALDH inhibitors with different isoform specificity38, including DEAB (pan-inhibitor, most specific for ALDH1 isoform39), Daidzin (ALDH2 inhibitor40), Gossypol (pan-inhibitor, most specific for ALDH3 isoform41), and Disulfiram (pan-inhibitor, most specific for ALDH1A142) on SUM149 breast cancer cells (data not shown).