The proteomic profiling of endometrial cancer cell lines revealed that ECC-1 and RL95-2 shared the ALDH isoforms ALDH3A1, ALDH3A2, ALDH3B1, ALDH3B2, ALDH7A1, ALDH9A1, and ALDH18A1 in their proteome. Here, ALDH3A2 is linked to endometrial cancer.