Id1 Expression And Its Correlation With Cell Proliferation And VEGF Expression In MCF-7 Breast Cancer Cell Strain

Objective: To study the influence of Id1 (inhibitors of DNA binding 1) gene on breast cancer cell proliferation and the expression of vascular endothelial growth factor(VEGF).Method:1. Positive,negative and empty eukaryotic expression vector of Id1 were transfected into the MCF-7 cell lines of breast cancer by liposome-mediated transfection. Hygromycin was used to select stabilized expressed cell lines. Reverse transcriptase polymerase chain reaction(RT-PCR)and cell immunohistochemical staining were perfermed to determine the expression of Id1.2.Growth activity of MCF-7 breast cancer cell was measured by cell counting and methyl thiazoly tetrazolium(MTT) test. Flow cytometry(FCM) was used to determine the proliferation index after Id1 transfection.3. The expression of VEGF was determined by cell immunohistochemical staining and ELISA to explore the relationship between Id1 and VEGF in the development and metastasize of breast cancer. Results:1.The result of RT-PCR and cell immunohistochemical staining shew that the level of Id1 of positive transfection cell lines was significantly higher than the control group(p<0.05),while the negative transfection cell lines expressed lower Id1(p<0.05).There was no difference between the nonsense eukaryotic vector transfection cell lines and the control group(p>0.05).2.Cell counting and MTT data shew that the proliferation of the positive transfection cell lines increased significantly.3. The result of FCM shew that the proliferation index of the positive transfection cell lines was significantly higher than the control group(p<0.05),while the negative transfection cell lines expressed lower Id1(p<0.05). There was no difference between the nonsense eukaryotic vector transfection cell lines and the control group(p>0.05). 4. The result of cell immunohistochemical staining shew that VEGF expression of positive transfection cell lines was significant higher than the control group(p<0.05),while the negative transfection cell lines expressed lower VEGF (p<0.05). There was no difference between the nonsense eukaryotic vector transfection cell lines and the control group(p>0.05).5. The result of ELISA shew that the concentration of VEGF increased proressively within a certain time in all the groups.At the same time, the concentration of VEGF of the positive transfection cell lines was significant higher than that in the control group(p<0.05),while it was extremely lower expressed in the negative transfection cell lines (p<0.05). There was no difference between the nonsense eukaryotic vector transfection cell lines and the control group(p>0.05).Conclusion:1.The level of Id1 expression of positive transfection cell lines is significant higher than the control group(p<0.05),while the negative transfection cell lines expresses lower Id1 level(p<0.05).2.Overexpression of Id1 promotes cell proliferation,while low-expression of Id1 inhibits cell proliferation.3.The level of Id1 expression is associate with the expression of VEGF in the breast cancer.Id1 can influence the invasion and metastasis of breast cancer by regulating the expression of VEGF in a certain pathway.