PIK3R1 and esophageal squamous cell carcinoma: The number of differently methylated genes increased to 10 (BNIP3, BRCA1, CCND1, HTATIP2, ITGAV, NFKB1, PIK3R1, PRDM16, PTX3 and TAP2) between ESCC and healthy control tissues (Table 3).