ALDHs may play an important role in the chemo-resistance ability, clonogenicity, and spherogenesis of the cancer stem cell (Ginestier et al., 2007; Wang et al., 2020), and the ALDH1A1 expression was correlated with poorer overall survival in breast cancer patients (Morimoto et al., 2009). Here, ALDH1A1 is linked to cancer.