Fig 2: siMAD2L2-induced cell apoptosis is regulated by oxaliplatin and MG132 in HCT116 and SW620 cells. The cells were treated with oxaliplatin or MG132 alone, or co-treated with oxaliplatin and MG132 for 24 h (oxaliplatin was incubated at 50 and 90 µM with HCT116 and SW620 cells, respectively; MG132 was incubated at 18 and 36 µM with HCT116 and SW620 cells, respectively). The induction of cell apoptosis was determined using TUNEL staining. Scale bar, 40 µm. MAD2L2, mitotic arrest deficient 2 like 2; si, small interfering RNA.

Fig 3: siMAD2L2-induced cell apoptosis is regulated by oxaliplatin and MG132 in HCT116 and SW620 cells. The cells were treated with oxaliplatin or MG132 alone, or co-treated with oxaliplatin and MG132 for 24 h (oxaliplatin was incubated at 50 and 90 µM with HCT116 and SW620 cells, respectively; MG132 was incubated at 18 and 36 µM with HCT116 and SW620 cells, respectively). The induction of cell apoptosis was determined via flow cytometry. MAD2L2, mitotic arrest deficient 2 like 2; si, small interfering RNA.

Fig 4: MAD2L2 expression is downregulated by oxaliplatin and MG132 in human colon cancer cells. (A) Western blotting was performed to detect the protein expression levels of MAD2L2 in HCT116 and SW620 cells. The cells were treated with oxaliplatin or MG132 alone, or co-treated with oxaliplatin + MG132 for 24 h (oxaliplatin was incubated at 50 and 90 µM with HCT116 and SW620 cells, respectively; MG132 was incubated at 18 and 36 µM with HCT116 and SW620 cells, respectively). One-way ANOVA followed by Tukey's multiple comparisons test was used to determine the statistical significance in (B) HCT116 and (C) SW620 cells. The data are presented as mean ± SD. n=3. **P<0.01, ***P<0.001 vs. blank. MAD2L2, mitotic arrest deficient 2 like 2.

Fig 5: Knockdown of MAD2L2 expression promotes Bcl-2-mediated apoptosis of colon cancer cells. The cells were treated with negative siRNA, siMAD2L2, siMAD2L2 + oxaliplatin, siMAD2L2 + MG132 and siMAD2L2 + oxaliplatin + MG132 (oxaliplatin was incubated for 24 h at 50 and 90 µM with HCT116 and SW620 cells, respectively; MG132 was incubated for 24 h at 18 and 36 µM with HCT116 and SW620 cells, respectively). Western blotting was performed to detect the expression levels of cell apoptosis-associated proteins. (A) Expression levels of Bax, Bak and Bcl-2 proteins in HCT116 and SW620 cells. One-way ANOVA followed by Tukey's multiple comparisons test was used to determine the statistical significance in (B) HCT116 and (C) SW620 cells. The data are presented as the mean ± SD. n=3. *P<0.05 vs. negative group; $P<0.05 vs. siMAD2L2 group; &P<0.05 vs. siMAD2L2 + oxaliplatin group; #P<0.05 vs. siMAD2L2 + MG132 group. MAD2L2, mitotic arrest deficient 2 like 2; si, small interfering RNA.