Fig. 3.

Nucleus transportation of SRSF1 exerts oncogenic effect via upregulating MKNK2b level. a HCT-116 and SW480 cells were transfected with either scrambled siRNA or siRNAs targeting SRSF1. The transfection efficiencies were verified by western blotting. The alterations of MKNK2 alternative splicing were tested by RT-PCR. b Quantitative PCR results further confirmed the role of SRSF1 on regulating MKNK2 alternative splicing. P value was based on unpaired Student’s t-test comparing with scrambled group. c MTT and colony formation (d) assays demonstrated that SRSF1-knockdown inhibited CAC cell proliferation. P value was based on unpaired Student’s t-test comparing with scrambled group. e Western blot results showed that silencing TNPO3 downregulated nucleus SRSF1 level, indicating nucleus importing of SRSF1 was at least partially depend on TNPO3. Moreover, RT-PCR data indicated that silencing TNPO3 attenuated the effect of SRSF1 on altering MKNK2 alternative splicing. f Quantitative PCR results further verified the role of TNPO3-siRNA on attenuating SRSF1-induced MKNK2a-MKNK2b switch. P value was based on unpaired Student’s t-test comparing with SRSF1 group. g MTT and colony formation (h) assays demonstrated that TNPO3-knockdown attenuated the oncogenic effect of SRSF1 on CAC cell proliferation. P value was based on unpaired Student’s t-test comparing with SRSF1 group