Fig. 5

USP22 knockout impairs NHEJ in NSCLC cells and sensitizes cancer cells to cisplatin treatment. a. Representative flow cytometry charts of the parent and USP22−/−H1299 cancer cells for HR and NHEJ reporter assays. b. Quantitative analysis of HR and NHEJ reporter; * P < 0.05, USP22−/− versus USP22+/+. Error bars are representative of three individual treated samples of two experimental duplicates. c. Representative flow cytometry apoptotic profiles of the parent A549 versus USP22−/− A549 (left panel) and the quantitative analysis of apoptotic cells (right panel) showing apoptotic cells were significantly increased in USP22−/− A549. d. Representative flow cytometry apoptotic profiles of the parent H1299 versus USP22−/− H1299 cancer cells (left panel) and the quantitative analysis of apoptotic cells (right panel) showing apoptotic cells were significantly increased in USP22−/− H1299 cells. The experiment was repeated three times and data represent the average of the early apoptotic and late apoptotic cells; ** P < 0.01. e. The in vitro proliferation curves of the parent A549 and A549-USP22−/− (left panel); the parent H1299 and H1299-USP22−/− cancer cells (right panel) over a period of 72 h of cisplatin (CDDP) treatment, cells were treated with 5 μM cisplatin and proliferation of each cell were measured by Kit-8 at 24 h, 48 h and 72 h post-treatment and presented as the averages of OD values of triplicated experiments