SOX7 is involved in aspirin-mediated growth inhibition of human colorectal cancer cells

Figure 1 Aspirin and SOX7 inhibit the growth of SW480 cells. A: Dose- and time-dependent effects of aspirin on the growth rates of SW480 human colon cancer cells. SW480 cells were treated for 24, 48 or 72 h in aspirin-containing culture medium; 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to estimate the survival percentage compared with untreated cells; B: Effect of SOX7 expression on cell proliferation. MTT assay was used to estimate the proliferation at different time points after transfection of SOX7 expression vector; C: Western blotting was used to verify the expression of SOX7 after transfection of SOX7 expression vector at indicated time points. MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide. ASA: Aspirin.

Figure 2 Aspirin upregulates SOX7 expression in SW480 cells. A: SW480 cells were transfected with pGL3-SOX7-luc plasmid, and relative luciferase activity was determined after treatment with different doses of aspirin for 24 h; B and C: Reverse transcription-polymerase chain reaction (B) and Western blotting (C) detected the expression of SOX7 after treatment with aspirin for 30 h; β-actin was used as the internal reference. ASA: Aspirin.

Figure 3 Knockdown of SOX7 counteracts the growth inhibitory effect of aspirin in SW480 cells. A: Western blotting verification of the interfering efficiency of SOX7 Short interfering RNA in aspirin-treated SW480 cells. β-actin was used as the internal reference; B: Effect of SOX7 knockdown on SW480 cell proliferation after treatment with different doses of aspirin for 48 h by moto-nuclear cell direc cytotoxicity assay assay. MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide.

Figure 4 Role of the p38MAPK pathway in aspirin-induced SOX7 expression. A: HEK 293T cells were transfected with p38α expression vector; reverse transcription-polymerase chain reaction (RT-PCR) was used to detect SOX7 mRNA level 30 h after transfection; B: SW480 cells were treated with 10 μmol/L SB203580 for 30 h and SOX7 mRNA level was measured by RT-PCR; C: SW480 cells were treated with aspirin or aspirin combined with SB203580 for 30 h and SOX7 mRNA level was measured by RT-PCR; D: Cells were treated as in Figure 4 and SOX7 protein level was detected by Western blot; E: SW480 cells were transfected with pGL3-SOX7-luc plasmid and various expression vectors as indicated for 24 h and relative luciferase activity was examined. ASA: Aspirin.