MKI67 and gastric cancer: And Ki67 protein in AGS-RESCUE cells was also restored compared with AGS-OTUB2-sh1 cells (Fig. 7a, b) Notably, the expression of p-Akt (Thr308) protein coincided with the expression of KRT80 protein and Ki67 protein, suggesting that OTUB2 activates the PI3K/Akt signaling pathway by deubiquitinating KRT80, thus promoting the growth and proliferation of gastric cancer cells.