LETMD1 and cancer: When HGC27-R cells were transfected with HCCR-shRNA1 combined with 5-FU treatment (0.0, 5.0 and 10.0 μg/mL) for 24 hours, it was found that the HCCR-shRNA1-mediated downregulation of HCCR significantly increased the 5-FU-induced apoptosis of chemotherapy-resistant cancer cells (P < 0.01; Fig. 2B, C).