ABSTRACT
Objective: To determine the expression of TAZ and its role in angiogenesis in gastric carcinoma. Methods: Immunohistochemical staining was performed to investigate the expression of TAZ and to determine whether a direct relationship exists between TAZ and β-catenin. Transfection with TAZ overexpression plasmid in MKN28 cells was conducted to induce exogenous expression of TAZ and a TAZ knockdown plasmid was transfected into MGC803 cells to reduce TAZ levels. The effects on endothelial cell formation, proliferation, and migration were determined by Matrigel three-dimensional culture, MTT proliferation assay and Transwell migration assay. In addition, the expression of TAZ and β-catenin in transfected gastric cancer cells was detected by Western blot. Results: Immunohistochemistry showed that TAZ protein was expressed in 64 of 150 gastric cancer sample tissues (43%), TAZ was localized in the nucleus, and its expression was associated with tumor grade, TNM stage, metastasis, and microvessel density (MVD) (P<0.05). In addition, the expression frequency of β-catenin in the TAZ positive group was 67.2%, which was significantly higher than that in the TAZ negative group, and the expression of TAZ was positively correlated with β-catenin. After transfection, TAZ overexpression increased the expression of β-catenin and enhanced HUVECs tube formation, proliferation, and migration. In the MGC803 cells transfected with the knockdown plasmid, β-catenin levels were decreased and HUVECs motility was inhibited. Conclusions: TAZ may promote angiogenesis in gastric cancer by promoting β-catenin expression.
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 per-formed 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 re-duce 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,me-tastasis,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 trans-fected 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.
ABSTRACT
Objective:To determine the expression of BMP4 in hepatocellular carcinoma (HCC) and to study the role of BMP4 in inducing epithelial-mesenchymal transition (EMT) to analyze the effect of BMP4 on the migration and invasion of HCC cells. Methods: The expression of BMP4 in HCC specimens was examined by immunohistochemistry staining, and the correlations were analyzed between the expression of BMP4 and clinicopathological data. The BMP4 expression plasmid was transfected into HepG2 cells to induce exogenous overexpression of BMP4 protein. The changes of HepG2 cell morphology were detected after BMP4 transfection by using a microscope; the changes of the expression of BMP4, EMT-related protein (E-cadherin, Vimentin) in HepG2 cells were detected by Western blot after transfection of BMP4;the wound healing assay in vitro was used to detect the effects of BMP4 gene transfection on the ability of migration of HepG2 cells;the invasion assay was used to determine the role of transfection of BMP4 on the invasive potential of HepG2 cells. Results: Immunohistochemistry staining method displayed that BMP4 expression was positively associated with age, histological differentiation, stage, and poor prognosis. After BMP4 overexpression, the morphology of HepG2 cells showed significant changes from a paving stone structure with cell-cell adhesion to a fibroblastic shape, which showed typical EMT change; Western blot exhibited that the expression of E-cadherin was downregulated and the Vimentin expression was upregulated in HepG2 cells;the wound healing and invasion assay showed that the migration and invasion potentials of HepG2 cells were significantly enhanced. Conclusion: BMP4, which displayed a high expression in HCC specimens, was closely associated with clinicopathologic data, and BMP4 may promote migration and invasion of HCC cells by inducing epithelial-mesenchymal transition.