Studies have reported that lower CLDN23 mRNA levels are associated with poorer OS.[40,57] There is also a Cox multivariate survival analysis showing that when CLDN23 is low expressed, the OS of gastric cancer patients is longer.[58] A recent study showed that low expression of CLDN23 was associated with longer OS in colorectal cancer patients of CMS4 and C4 subtypes. This evidence concerns the gene CLDN23 and gastric cancer.