IQGAP1 interacts with β-catenin and regulates β-catenin expression.

(A) Endogenous IQGAP1 interacts with β-catenin in HepG2 cells. 500ug of HepG2 cell lysate was immunoprecipitated with anti-IQGAP1 antibodies, and bound proteins were analyzed by immunoblotting with the indicated antibodies. 5% of total lysate was loaded as a control (input). (B) The IQGAP1 overexpression improved the expression of β-catenin. Transfection with pCMV6 empty plasmids was taken as a control and the untreated HepG2 cells were taken as a mock. flag-IQ: pFlag-IQGAP1 plasmids. (C) The IQGAP1 knockdown by IQGAP1 siRNA (si-IQ) reduced β-catenin expression. Transfection with non-target siRNA was taken as a control (si-NC), and untreated HepG2 cells were taken as a mock. (D)The expression of IQGAP1 and β-catenin was gradually increased in several HCC cell lines. LO2 was a normal liver cell line. 97L: MHCC-97L; 97H: MHCC-97H.