shPTGR1 affected the expression of cell cycle regulatory proteins. (a) The levels of CDK1, cyclin A2, CDK2, and cyclin B1 protein were analyzed by western blot in shCon and shPTGR1 infected 95D cells. GAPDH was used as an internal loading control. (b) Correlation between PTGR1 and CDK1/cyclin A2/CDK2/cyclin B1 mRNA expression in lung cancer is observed. Pearson’s correlation coefficient test.