SHMT2 is critical for CRC cell proliferation, migration, and invasion dependent on β-catenin. (A) The overexpression of Flag-β-catenin in HCT116 and DLD-1cells after SHMT2 knockdown was confirmed by western blot analysis. (B) Cell proliferation was detected by CCK8 assay after stable SHMT2 knockdown with the re-expression of Flag-β-catenin (n = 3). *** p < 0.001; ordinary one-way ANOVA multiple comparisons test. (C) Representative images (top) of the Transwell migration and invasion assay using CRC cells after stable SHMT2 knockdown with the re-expression of Flag-β-catenin. The number of migrated cells was counted in three random fields per chamber and statistically analyzed (bottom). Scale bar, 100 μm. *** p < 0.001; ordinary one-way ANOVA multiple comparisons test. (D)-(E) Western blot analysis (D) and quantification (E) of vimentin, E-cadherin, and EMT-associated transcription factors in CRC cells with β-catenin overexpression after SHMT2 knockdown. * p < 0.05, ** p < 0.01, *** p < 0.001; ordinary one-way ANOVA multiple comparisons test. The data are presented as the mean ± SD from at least three independent experiments. Error bars are SD.