CCND1 and colorectal carcinoma: Furthermore, western blot analysis revealed an increase in the levels of phosphorylated GSK-3β, AKT and PI3K, as well as the protein levels of β-catenin, Cyclin D1 in RKO cells overexpressing NUBP2, which was partially reversed upon treatment with GSK3 inhibitor CHIR-99021 HCl (Figs. 5D and S1), implying that NUBP2 might regulate CRC EMT through PI3K/AKT/GSK3β signaling.