HOXA13 and gastric cancer: Similar to HOXD13, HOXA13 might be related to the pathogenesis of both poly-Ala tract expansion-related hand-foot-genital syndrome (HFGS) [67,236] and some types of cancer, such as thyroid [237] and gastric cancers [238] characterized by the aberrant expression of HOXA13, both at gene and protein levels.