Expression Of MAP2K4 And Preliminary Study On Its Function And Molecular Mechanisms In Breast Cancer

Background and ObjectivesBreast cancer is the most common cancer of women.It is a heterogeneous disease derived from mammary gland epithelial tissue which is related to age,estrogen,family history,gene susceptibility and other factors.At present,a variety of gene mutations and abnormal expression are widely involved in the pathogenesis of breast cancer.Through the study of more related genes,the pathogenesis of breast cancer still remains unclear.MAP2K4 is a member of the mitogen-activated protein kinase activator family.After activated by upstream signaling,MAP2K4 can phosphorylate JNK and P38 to regulate inflammation and cell proliferation processes,which plays an important role in tumorigenesis.MAP2K4 has been reported in many tumors initially,but these researchdid not report the specific role and molecular mechanism of MAP2K4 in breast cancer.In this study,we will explore the exact function of MAP2K4 in breast cancer.It will further reveal the pathogenesis of breast cancer and provide new gene targets for the prevention and treatment ofbreast cancer.Contents and methods1.The function on cell biology of MAP2K4 in breast cancer cell.1)MCF-7 and A231 cell lines were treated with stable expression of MAP2K4 slow virus,and the two cell lines were established.Detecting the expression of MAP2K4 in MCF-7 and A231 cells by quantitative real-time PCR(qPCR)and westernblot.2)After transfection with MAP2K4 slow virus,MTT,cell cycle and Edu assay were used to observe the ability of cell growth,proliferation of MCF-7 and A231 cells with MAP2K4 overexpressed.Transwell and Boyden chamber assay were used to test the effects of MAP2K4 overexpression on migration and invasion.3)After that,transiently transfecting MAP2K4 silencing small RNA in overexpression MAP2K4 cells,MTT assay and Edu assay were used to detect the proliferation of MCF-7 and A231 cells.Transwell assay and Boyden assay were used to detect the expression of MCF-7 and A231 cells on the impact of invasion and migration and distant metastasis changes.2.The molecular mechanism of MAP2K4 in breast cancer.Detecting the expression of proteins involved in PI3K/Akt signaling pathways by western blot in MAP2K4 overexpression cells.3.MAP2K4 interacting proteins1)Detecting the presence of interacting proteins MAP2K4 protein by immunoprecipitation(CoIP).2)Detecting the localization of MAP2K4 and Vimentin in cells by immunofluorescence microscopy.4.Clinical association between MAP2K4 and ER in Breast Cancer specimens.1)Immunohistochemical staining was used to the expression of MAP2K4 in breast cancer specimens.2)Clinical association between the expression of MAP2K4 and clinicopathological parameters in breast cancer specimens.3)Clinical association between the expression of MAP2K4 and ER in breast cancer specimens.Results1.MAP2K4 promotes MCF-7 and A231 cells cell proliferation as well as cell cycle transition in vitro and in vivo2.MAP2K4 promotes MCF-7 and A231 cell migration,invasion,and metastasis in vitro and in vivo.3.Silencing MAP2K4 reverses proliferation,invasion and migration of MCF-7 and A231 cells after stable overexpression of MAP2K4.4.MAP2K4 promotes proliferation and invasion of tumor cells by activating PI3K/Akt pathway signaling.5.Further analysis of the protein related to MAP2K4detects potentially interacting proteins of MAP2K4 and their colocalization in cells.6.MAP2K4 and ER expression was negatively correlated in invasive breast cancer tissue.