ABSTRACT
Objective: To study the mechanism of Wnt/β-catenin signaling pathway in the enhanced malignant phenotype of A549 cells of human non-small cell lung cancer induced by the anti-angiogenesis therapy. Methods: The siRNA technique was employed to inhibit the expression of vascular endothelial growth factor (VEGF) in A549 cells and simulate the clinical course of anti-angiogenesis therapy. Real-time PCR and western blot were used to study the change in the expression of Wnt/β-catenin signaling molecules at the mRNA and protein level respectively, as well as the effect on the epithelial mesenchymal transition in A549 cells. The proliferation and invasion abilities of tumor cells were detected to discuss the mechanism of Wnt/β-catenin signaling pathway in the enhanced malignant phenotype of non-small cell lung cancer induced by the anti-angiogenesis therapy. Results: The specific siRNA could significantly inhibit the expression of VEGF in cells to simulate the anti-angiogenesis therapy. Under the action of 50 nM VEGF siRNA, the proliferation ability of A549 significantly increased (P < 0.05). After being treated with VEGF siRNA, the invasion ability of cells increased. Twenty-four hours after the transcription of 50 nM siRNA into cells, the number of cells that come through the membrane was 278.3 ± 12.9. Compared with the Ctrl siRNA group, when VEGF was inhibited, the expression of β-catenin and Cyclin D1 increased by 86% and 55% respectively. Meanwhile, the expression of E-cadherin decreased, while the one of vimentin increased. Conclusions: siRNA can significantly inhibit the expression of VEGF. For the anti-angiogenesis therapy, the inhibited expression of VEGF can activate the Wnt/β-catenin signaling pathway to cause the epithelial mesenchymal transition and then the enhanced malignant phenotype of non-small cell lung cancer.
ABSTRACT
OBJECTIVE@#To study the mechanism of Wnt/β-catenin signaling pathway in the enhanced malignant phenotype of A549 cells of human non-small cell lung cancer induced by the anti-angiogenesis therapy.@*METHODS@#The siRNA technique was employed to inhibit the expression of vascular endothelial growth factor (VEGF) in A549 cells and simulate the clinical course of anti-angiogenesis therapy. Real-time PCR and western blot were used to study the change in the expression of Wnt/β-catenin signaling molecules at the mRNA and protein level respectively, as well as the effect on the epithelial mesenchymal transition in A549 cells. The proliferation and invasion abilities of tumor cells were detected to discuss the mechanism of Wnt/β-catenin signaling pathway in the enhanced malignant phenotype of non-small cell lung cancer induced by the anti-angiogenesis therapy.@*RESULTS@#The specific siRNA could significantly inhibit the expression of VEGF in cells to simulate the anti-angiogenesis therapy. Under the action of 50 nM VEGF siRNA, the proliferation ability of A549 significantly increased (P < 0.05). After being treated with VEGF siRNA, the invasion ability of cells increased. Twenty-four hours after the transcription of 50 nM siRNA into cells, the number of cells that come through the membrane was 278.3 ± 12.9. Compared with the Ctrl siRNA group, when VEGF was inhibited, the expression of β-catenin and Cyclin D1 increased by 86% and 55% respectively. Meanwhile, the expression of E-cadherin decreased, while the one of vimentin increased.@*CONCLUSIONS@#siRNA can significantly inhibit the expression of VEGF. For the anti-angiogenesis therapy, the inhibited expression of VEGF can activate the Wnt/β-catenin signaling pathway to cause the epithelial mesenchymal transition and then the enhanced malignant phenotype of non-small cell lung cancer.
ABSTRACT
Objective To investigate the expression of syndecan-1 (SDC1) in glioma cells and the effects of synde?can-1 knockdown on the proliferation and invasion of A172 cells. Methods The expression of syndecan-1 in glioma cells was analyzed using quantitative Real-time PCR and Western blotting. A172 cells were transfected with lentiviral vector carrying SDC1 shRNA to establish a stable SDC1-silencing cell line. The cell proliferation was analyzed by MTT assay. Trypan blue exclusion assay and flow cytometry, and Transwell assays were performed to measure the migration and invasion abilities, respectively. The mRNA and protein and expression levels of SDC1, Proliferation Cell Nuclear An?tigen (PCNA) and Matrix Metalloproteinase 9 (MMP-9) were detected by using qRT-PCR and Western blotting. Results The expression levels of SDC1 were significantly different in different glioma cell lines. The stable SDC1-silencing cell line was successfully established, in which the mRNA and protein expression levels of SDC1 were significantly decreased (P<0.05). SDC1 knockdown significantly reduced the cell proliferation, migration(58.40±5.24 vs. 255.8±16.09、226.5± 22.84,F=126.4,P<0.05)and invasion(61.67 ± 16.26 vs. 233.70 ± 17.24、244.30 ± 28.15,F=69.87,P<0.05)compared with either control group or blank group. SDC1 knockdown also significantly decreased the mRNA and protein expression levels of PCNA and MMP-9 (P<0.05). Conclusion:SDC1 knockdown suppresses the capacities of proliferation, invasion and migration of glioma A172 cell, implying that SDC1 may serve as a novel target in the biotherapy of glioma.