ALDH1A2 and neoplasm: Each ALDH1A isoform was stably expressed in these SCP28-RARE-Luc reporter cells, and tumor growth measurements from orthotopically implanted tumors in immunodeficient NSG mice revealed that overexpression of ALDH1A2 or ALDH1A3 did not affect tumor growth while ALDH1A1 suppressed primary tumor growth (Figures 1G and 1H).