Differential expressions of cyclin G (CCNG) and increased RING finger and WD repeat domain protein 2 (RFWD2), the two proteins involved in negative autoregulatory feedback loops of the p53 response observed in this study, were concomitant with the modified transcriptional direction addressed in gastric cancer tissues and in ovarian and breast cancer tissues, respectively (Dornan et al., 2004; Gao et al., 2018). Here, COP1 is linked to breast carcinoma.