Nevertheless, Yang et al (44) observed that homeobox genes from cluster A (HOXA4, HOXA5, HOXA7, HOXA9 and HOXA13) were highly expressed in gastric cancer cell lines and suggested that the mechanism of gastric carcinogenesis possibly involves specific chromosomal rearrangement and up-regulation of HOX genes. This evidence concerns the gene HOXA5 and gastric cancer.