The expression of PVT1 is inversely correlated with p15/p16 protein level in GC tissues. (A) Immunostaining of EZH2 was negatively or very weakly positive in non-tumor gastric tissues, but was strongly positive in corresponding tumor tissues. The immunoreactivity of EZH2 protein in GC tissues showed a statistically significant positive correlation with PVT1 expression. Error bars indicate means ± standard errors of the mean. (B) Flow cytometry assays were performed to detect the cell cycle after si-EZH2 transfection. (C) The level of p15/p16 in GC tissues was determined by immunohistochemistry. PVT1 expression was inversely correlated with p15/p16 protein level. *, P < 0.05, **, P < 0.01.