Effect Of Knockdown SOX2 Gene On Proliferation And Migration Of Canine Mammary Gland Tumor Cells

Canine mammary gland tumors are one of the most common tumors in female dogs.Dogs as companion animals have many similarities with humans in terms of living environment.Therefore,spontaneous mammary gland tumors in dogs are good model for human mammary gland tumors.SOX2 is highly expressed in a variety of cancers and it is a hotspot of cancer research,but its mechanism in tumorigenesis and cancer development has not been fully clarified.Therefore,the effects of SOX2 on proliferation and migration of canine mammary tumor cells were studied in CHMp and CHMm cells isolated from primary and metastatic tumors of canine mammary gland tumors.In this experiment,si RNA of SOX2 gene was transfected into canine mammary gland tumor cell lines CHMp and CHMm with Lipofectamin 2000 as transfection reagent,and the knockdown effect of SOX2 was examined.The proliferation rate of each group of cells was examined by CCK-8 and colony formation assay.The migration ability was detected by Wound-healing and Transwell chamber migration assays respectively after knockdown SOX2 of CHMp and CHMm.Western blot was used to detected changes in the expression of related proteins.The sensitivity of tamoxifen and cisplatin to each group of cells was respectively detected by IC50.Results: 1.To detect the knockdown effect of SOX2 in transfected cells,the expression of SOX2 protein was detected by western blotting.The expression level of the protein in SOX2 decreased,and the difference was extremely significant compared with the control group(P<0.001).2.CCK-8 and clone formation assays were used to detect cell proliferation.Compared with the control group,the proliferation rate and colony formation rate of CHMp and CHMm cells with SOX2 knockdown were significantly decreased(P<0.001).3.The wound healing experiment and Transwell chamber migration assay were used to detect cell migration ability.The wound healing rate of CHMp and CHMm cells and the number of cells passing through Transwell chambers were significantly decreased after SOX2 knockdown(P<0.001).4.The expression of β-catenin in CHMp and CHMm cells with SOX2 knockdown was significantly decreased(P<0.001).5.SOX2 knockdown can inhibit Hippo signaling pathway.The expression of NF2 protein in CHMp and CHMm cells with SOX2 knockdown was significantly higher than that in control groups,and the expression of YAP protein was significantly decreased(P<0.001).6.The expression of EMT marker E-cadherin in SOX2 knockdown CHMp and CHMm cells was significantly increased,and the expression levels of N-cadherin and Vimentin were significantly decreased(P<0.001).7.After knocking down the SOX2,the IC50 of 4-hydroxytamoxifen and cisplatin was significantly reduced in canine mammary gland tumor cells(P<0.001),and the sensitivity of canine mammary tumors to 4-hydroxytamoxifen and cisplatin was improved.In summary,this experiment successfully constructed SOX2 knockdown canine mammary gland tumor cells model.SOX2 knockdown can reduce the proliferation and migration ability of canine mammary tumor cells by inhibiting Hippo signaling pathway,and improve the sensitivity of tamoxifen and cisplatin in canine mammary gland tumor cells.Further improved the mechanism of SOX2 regulation of mammary gland tumors.SOX2 is one of the therapy targets of canine gland tumors.