The effect of ADI on the cell proliferation, apoptosis, cell cycle, and colony formation of pancreatic cancer cells. A, The proliferation-inhibitory effect of ADI on BxPC-3, PANC-1, SW1990, and MIA PaCa-2 cells was measured by the MTT assay. *, P < 0.05 as compared with the control group (0 mU/mL ADI). B, Cell cycle progression of primary pancreatic cancer cell lines BxPC-3 and PANC-1 after treatment with or without ADI was analyzed by FACS. *, P < 0.05 as compared with the control group (0 mU ADI/mL); NS, not significant. C, The percentage of apoptotic PANC-1 cells treated with ADI was calculated by FACS. D, The percentage of apoptotic BxPC-3 cells treated by ADI for 48 h was calculated by FACS. E, ADI (1 mU/mL) intervention altered cell morphology of PANC-1 cells but not BxPC-3 cells. F, The colony forming ability of PANC-1 cells was altered by ADI intervention, while BxPC-3 colony formation was not changed. *, P < 0.05 as compared with the control group (0 mU ADI/mL).