| Background:Triple-Negative Breast Cancer(TNBC)is that it lacks expression of estrogen receptor(ER),progesterone receptor(PR)and human epidermal growth factor receptor 2(HER2).This form of breast cancer is marked by its invasive phenotype,poor prognosis and lack of specific therapies.Non receptor tyrosine kinase 2(TYK2)is a member of the JAK family,is involved in a variety of cytokine signaling pathways,and human cancer are closely related.Previous study showed that overexpression of TYK2 in the triple-negative breast cancer cell lines,but the molecular mechanism of TYK2 involves in the tumorigenesis of triple-negative breast cancer is still not clear.The most human tumors with P53 gene mutation,Wild type P53 is the tumor suppressor gene,with the regulation of cell cycle,DNA repair,cell aging and playing an important role in apoptosis.However,Mutant P53(mtp P53)can promote tumor cell migration,invasion and metastasis.Researchs indicate that the P53 mutation was expressed in MDA-MB-231.and triple-negative breast cancer with P53 mutation has poor clinical prognosis.In recent years,studies have indicated that there are interactions between JAK family and P53.But there are few reports about the correlation between TYK2 and mutant P53.Objective: The purposes of this study is to validate the influence of TYK2 gene on the proliferation,migration and apoptosis of breast cancer cell line MDA-MB-231.To further clarify the interaction of TYK2 in triple breast cancer and mtp P53.Providing new ideas and experimental evidence for the treatment of triple negative breast cancer.Methods:(1)By using the si RNA transient transfection technique,TYK2-si RNA and P53-si RNA were transfected with MDA-MB-231 cells,and cells transfected with invalid sequence served as negative control group.Western blot was performed to detect the expression of protein of TYK2 and P53.(2)MTT method was used to detect the proliferation of MDA-MB-231 cells after interfering with Tyk2 and p53.(3)The migration of cells was detected by wound scratch assay.(4)Cell apoptosis was tested by flow cytometry.Results: 1.Western blotting revealed that the expression of TYK2 protein in si TYK2 transfection group was significantly lower than that in negative control group,while the expression of P53 protein in si TYK2 transfection group was also decreased than negative control groups.Compared with negative control group,the expression of P53 protein was lower in breast cancer MDA-MB-231 cells by interfering with the P53 gene,and the expression of TYK2 protein was aslo decreased.2.MTT results showed that the cell proliferation rate in the joint or single transfected si TYK2,si P53 group are notable decreased than negative control group.But the increment rate of the co-transfection group decreased had no obviously improvement when compared with si P53 transfected group.3.Wound scratch assay indicated that cell migration ability of co-transfection group and single transfection of si TYK2 group and si P53 group were notable decreased.But the imigration ability of the co-transfection group decreased had no obviously improvement when compared with si TYK2 transfected group or si P53 transfected group.4.Flow cytometry suggested that the cell apoptosis rate in siTYK2 transfected group and si P53 transfected group and co-transfection group are notably increased than negaive control group.Conclusion: 1.When silencing TYK2 gene,The expression of P53 gene can be inhibited in MBA-MB-231 cell line.While silent P53 gene also downregulated the expression of TYK2 gene.Suggesting that TYK2 and mtp P53 have associated role in the occurrence and development of triple negative breast cancer,both can be through the regulation of genes of transcription and translationin in a certain signaling pathway directly or indirectly.2.TYK2 gene silencing can lead to increased apoptosis of breast cancer cell line of MDA-MB-231,reduce the proliferation and migration,suggesting that the TYK2 gene can affect MDA-MB-231 through a mechanism of cell proliferation,migration and apoptosis of biological behavior.3.mt P53 gene silencing can increase the apoptosis of breast cancer cell line MDA-MB-231 and reduce the proliferation and migration ability,which plays an important role in the development of triple negative breast cancer. |
