Fig. 6

IQGAP3 activates the TGF-β signaling pathway. a Gene Set Enrichment Analysis shows that IQGAP3 expression is positively correlated with TGF-β–activated gene signatures (COULOUARN_TEMPORAL_TGFB1_SIGNATURE_UP and COULOUARN_TEMPORAL_TGFB1_SIGNATURE_DN). b TGF-β–responsive luciferase activity is measured in the indicated cells after 48 h culture with or without TGF-β1 (5 ng/mL) for 20 h using the dual luciferase assay. Values are presented as mean ± SD of triplicate samples. * p < 0.05. c Western blot analysis of the phosphorylated and total levels of Smad2 and Smad3 in the indicated HepG2 and HCCLM3 cells. GAPDH is used as a loading control. d IQGAP3 regulates the expression levels of numerous well-known genes downstream of TGF-β, as shown by real-time polymerase chain reaction analysis. * p < 0.05. e Western blot analysis of Smad2 and Smad3 expression in the cytoplasm and nucleus of HCCLM3 cells. GAPDH and p84 are used as loading controls for the cytoplasmic and nuclear fractions, respectively. HCC hepatocellular carcinoma, IQGAP3 IQ motif-containing GTPase activating protein 3, SD standard deviation, GAPDH glyceraldehyde 3-phosphate dehydrogenase, TGF-β transforming growth factor-β