| Background:Breast cancer(BC)has become a major killer of contemporary women’s health,and has gradually attracted people’s attention.The pathogenesis of breast cancer is complex,involving inflammatory reaction,DNA methylation,cell proliferation,oxidative stress,signal transduction disorder,gene mutation,immune response,etc.At present,although the available treatment methods for breast cancer patients include surgery,radiotherapy,chemotherapy,targeted treatment,traditional Chinese medicine treatment and biological treatment,there are still many problems such as large adverse reactions,insignificant therapeutic effects.Thus,there remains an urgent need to further investigate the pathogenesis of breast cancer and identify novel treatment strategies to improve the survival rate of clinical patients.Synaptotagmin(SYTs)is a family of membrane-related synaptic vesicular transport proteins.SYTs is a rich and evolutionarily conserved integrated membrane protein,a large family with 17 subtypes(SYT1-SYT17),which is mainly used as a sensor for calcium signal transduction in cell secretion activities.Previous studies have shown that SYTs family members play a key role in a variety of cell life activities.In addition,with the continuous in-depth study of SYTs family members,more and more evidence shows that some members of the family are also involved in the pathogenesis and progression of human malignant tumors.Synaptotagmin 13(SYT13)is an atypical member of SYTs.Studies have found that SYT13 is related to the occurrence and development of gastric cancer,lung adenocarcinoma,liver cancer,colorectal cancer and other cancers.SYT13 plays an significant role in the biological behavior of cancer cells and tumor growth.However,the role of SYT13 in breast cancer is still unclear,so this study aims to explore the very possible mechanism of action of SYT13 overexpression on the biological function of breast cancer cells,to provide clues for the molecular mechanism of the occurrence and development of breast cancer,and to provide theoretical basis for finding new treatment strategies to improve the survival rate of clinical patients.Methods: 1.Collect 25 for breast cancer and cancer adjacent tissues,through qRT-PCR in detection of breast cancer and cancer adjacent tissues SYT13 mRNA expression.Then,8 tissue pairs with different SYT13 mRNA were selected to detect the expression of SYT13 protein by Western blot.2.Normal human breast epithelial cells(MCF-10A)and five breast cancer cells(HCC1937,MDA-MB-231,MDA-MB-453,MDA-MB-468 and MCF-7 cells,respectively)were selected.The expression of SYT13 mRNA was verified by qRT-PCR,and the expression of SYT13 protein was verified by Western blot.The strain with the lowest expression of SYT13(MDA-MB-231)was used for follow-up in vitro experiments.SYT13 overexpression vector was constructed to transfect MDA-MB-231 cell lines,and then transient strains were constructed to perform cell phenotype experiments,which confirmed the effect of SYT13 on the proliferation,metastasis and invasion of breast cancer cells.The experiments mainly included Cell Counting Kit-8(CCK-8)experiment,EDU staining,flow cytometry,cell scratch experiment and Transwell experiment.3.The potential mechanism of carcinogenic effect triggered by SYT13 was discussed and verified.Activation of the FAK/AKT signaling pathway has been shown to play a role in regulating breast cancer progression.The regulation of SYT13 on malignant phenotype of gastric cancer cells is related to FAK/AKT signaling pathway.Therefore,this study speculates that SYT13 may also be related to the activation of FAK/AKT signaling pathway in the occurrence and development of breast cancer.PF573228(FAK inhibitor)and MK2206(AKT inhibitor)further elucidate that SYT13 promotes breast cancer cells through the FAK/AKT signaling pathway.Results: The mRNA and protein levels of SYT13 in breast cancer tissue and breast cancer cell line were higher than those in paracancer tissue.In cell function experiments,overexpression of SYT13 promoted the proliferation of MDA-MB-231 cells by up-regulating cyclin D1 and CDK4 and down-regulating P21,and increased the number of cells in S phase of the cell cycle.Overexpression of SYT13 promotes migration and invasion of MDA-MB-231 cells by decreasing E-cadherin and increasing Vimentin.In addition,overexpression of SYT13 can up-regulate p-FAK and p-AKT in breast cancer cells,PF573228(FAK inhibitor)and MK2206(AKT inhibitor)can inhibit p-FAK and p-AKT up-regulated by SYT13.The effect of SYT13 overexpression on promoting proliferation,metastasis and invasion of MDA-MB-231 cells was also reversed.In addition,PF573228 and MK2206 also reversed Syt13-induced up-regulation of cyclin D1 and Vimentin.Conclusion: This study suggests that overexpression of SYT13 promotes proliferation,metastasis,and invasion of breast cancer cells by activating the FAK/AKT signaling pathway.It suggests that SYT13 may be a potential target for the treatment of breast cancer patients... |
PDF Full Text Request