ERRFI1 and liver cancer: The protein expression of ERRFI1 (ERBB receptor feedback inhibitor, also known as MIG6 or GENE33), which is a negative regulator of EGFR, is reported to be down-regulated in skin, breast, pancreatic, ovarian, and liver cancer [9, 10], and augmented protein expression of EGFR is known to be involved with radio-resistance [11].