ALDH isoforms ALDH1A3 and ALDH1L1 have shown potential as prognostic markers and therapeutic targets in gastric cancer (Li et al., 2016), whilst Ajani et al showed that ALDH1+ tumour cells from OAC and GEJA resection specimens were more resistant to chemoradiotherapy, as compared to tumour cells with low ALDH1 expression (Ajani et al., 2014; Honing et al., 2014). The gene discussed is ALDH1A1; the disease is gastric cancer.