The Function Of Zinc-finger Protein 382 In Breast Cancer As A Tumor Suppressor

Objective: The purpose of our study was to detect the expression status of the new tumor suppress ZNF382 in breast cancer cell lines, paired breast tumor tissues and normal breast epithelial tissues. This gene is located on the long arm of chromosome 19, plays critical roles in the regulation of many cellular processes including proliferation and apoptosis in colon cancer and nasopharyngeal carcinoma cells. According to the reports that ZNF382 protein can distinctly inhibit NF-κB and AP-1 signaling play as a tumor suppressor in multiple carcinomas. Besides ZNF382 could inhibit tumorigenesis through heterochromatin-mediated silencing by interacted with heterochromatin protein HP1. This could make the downstream target oncogenes silence or inactivation. It was found that the expression of ZNF382 was down-regulation frequently in both breast cancer tissues and breast cancer cells. So we put forward the hypothesis that whether ZNF382 plays significant roles in the development of breast cancer as a tumor suppressor gene.Methods:1. We detected the expression status of ZNF382 in breast cancer cell lines BT549, MDA-MB-231, MCF-7, T47 D, MDA-MB468, T47 D, SK-BR-3, BT549, HBL100 and normal breast epithelial tissues by RT-PCR and we used real-time quantitative PCR to check the expression of ZNF382 in paired breast tumor tissues.2. The breast cancer cells MB231 and MCF7 expressed lower yields of ZNF382 and were transfected by plasmid. Then we established stable expression ZNF382 cells through screening and identification of cell lines.3. In vivo cell function experiment show that flow instrument to detect the cell cycle, CCK 8, clone forming test, scratch test, migration, at least a tumor-burdened experiments, observation group(expressed genes ZNF382 group) and control group(empty plasmid transfected) on human breast cancer cell cycle, proliferation and clone formation, cell migration ability, and the influence of cell proliferation in vitro experiment.Result:1. We found the ZNF382 was always widely expression in breast cancer tissues than in the adjacent cancer tissues and normal breast tissue. The difference was statistically significant. The expression of ZNF382 was always down-regulation in MB231 and MCF7 was silenced.2. Re-expression of ZNF382 can block the cell cycle in G0 / G1 phase obviously from 41.09% to 50.49%(p<0.05) in MB231 cell and from 54.56% to 62,7%(p<0.05) in MCF7 cell compared to controls; In colony formation test, we observed that overexpression of ZNF382 could distinctly inhibit MB231 and MCF7 cells both in clone size and quantity(p < 0.001); In CCK8 cell proliferation test, we check the OD value in 0 days, 2 days, 4 days, 6 days compared with the control group. Re-expression of ZNF382 can suppress MCF7 cell proliferation ability obviously; as well as ZNF382 can significantly inhibit MB231 cell migration ability by the experiment of scratches and Transwell migration assay.Conclusion:We found the expression of ZNF382 was always lower in breast cancer tissues than the adjacent cancer tissues and normal breast tissues. Re-expression of ZNF382 in MB231 and MCF7 cells can obviously inhibit cell proliferation and migration, block cell cycle in G0/G1. In conclusion: ZNF382 may play a vital role and participate in the key steps through the development of breast cancer.