Abstract:
Objective To examine the expression of IQGAP1 in hepatocellular carcinoma and its effect on vasculogenic mimicry (VM).
Methods Immunohistochemical staining was performed to investigate the expression of IQGAP1. CD31/PAS double staining was performed to detect VM and analyze the correlation of IQGAP1 and VM. HepG2 cells were transfected with an IQGAP1 overexpression plasmid to induce exogenous expression of IQGAP1, and an IQGAP1 knockdown plasmid was transfected into SMMC7721 cells to reduce IQGAP1 levels. The expression of cancer stem cell markers CD133, CD44, Sox2, and ALDH1 was analyzed by Western blot and compared with that in the control. Cellular functional experiments were used to determine the role of IQGAP1 in promoting cancer cells' ability of invasiveness and migration, proliferation, and VM formation.
Results Immunohistochemical analysis revealed that IQGAP1 was mainly located in the cell membrane and/or cytoplasm, and the staining intensity was correlated with tumor grade, metastasis, and VM (P < 0.05). Cells transfected with the overexpression plasmid showed enhanced CD133, CD44, Sox2, and ALDH1 levels due to the increase in IQGAP1 and exhibited increased invasion ability, proliferation, and VM formation. In the SMMC7721 cells transfected with the knockdown plasmid, CD133, CD44, Sox2, and ALDH1 levels were decreased and motility was inhibited.
Conclusions IQGAP1 supports malignant behavior in hepatocellular carcinoma and may promote VM by increasing stemness.