Fig 1: TRIM9 regulates cell proliferation and intestinal barrier function in IEC-6 cells likely through modulating DUSP6 expression. The overexpression efficiency of DUSP6 in IEC-6 cells was detected via (A) reverse transcription-quantitative PCR and (B) western blotting. **P<0.01, ***P<0.001 vs. Vector. IEC-6 cells were transfected with oeTRIM9 combined with oeDUSP6. (C) Cell proliferation at 0, 12, 24 and 48 h was detected using a CCK-8 assay. (D) Cell apoptosis was detected with a flow cytometer. (E) TEER was measured in each group. (F) The fluorescence intensity of FITC was tested in each group. (G) The levels of IL-1β and TNF-α expression were detected with an ELISA. (H) The protein expression levels of ZO-1, DUSP6, Claudin-4 and p-P38/P38 were detected via western blotting. *P<0.05, **P<0.01, ***P<0.001 vs. Vector; #P<0.05, ##P<0.01, ###P<0.001 vs. oeTRIM9 + Vector. IEC-6 cells were treated with irinotecan combined with oeDUSP6. (I) Cell proliferation at 0, 12, 24 and 48 h was detected with a CCK-8. (J) TEER was measured in each group. (K) The fluorescence intensity of FITC was tested in each group. (L) Cell apoptosis was detected with a flow cytometer. **P<0.01, ***P<0.001 vs. Vector; #P<0.05 vs. irinotecan + Vector. TRIM9, tripartite motif protein 9; DUSP, dual-specificity phosphatase; oe, overexpression; CCK-8, Cell Counting Kit-8; TEER, transepithelial electrical resistance; TNF-α, tumor necrosis factor-α; IL-1β, interleukin-1β; ZO-1, zona occludens protein 1; p-, phosphorylated.