Cation transport regulator 1 is a novel ER stress‐inducible gene, and in the presence of ER stress, CHAC1 mRNA levels are upregulated.3, 4 Infection is a factor that stimulates ER stress,20, 21, 22 and our previous in vitro study demonstrated that H. pylori‐triggered ER stress led to the overproduction of CHAC1.12 To date, there have been no IHC studies of CHAC1 expression in human tissues because commercially available anti‐CHAC1 antibodies cannot be used in FFPE samples. The gene discussed is CHAC1; the disease is infection.