PCNA and tongue squamous cell carcinoma: Recently, several studies report that PAIP1 could regulated expression of AKT/GSK-3 β signaling pathway genes in lung cancer, Ki67, Pcna, Bax/Bcl2 and caspase-3 in tongue squamous cell carcinoma, and PLK1 in gallbladder cancer, respectively (Bi et al., 2021; Wang et al., 2019c; Xie et al., 2020).