CDKN1A and gastric cancer: Current studies have found that histone deacetylation occurs at the promoter region of a number of genes in gastric cancer, including p21(WAF1/CIP1) [34], RIP-associated ICH1/CED3-homologous protein with a death domain (RAIDD) [35], DTW domain containing 1 (DTWD1) [36], p53 upregulated modulator of apoptosis (PUMA) [31], gelsolin and retinoic acid receptor beta [37], deleted in liver cancer-1 (DLC1) [38], and thioredoxin-interacting protein (TXNIP) [39].