The Role Of KAI1 In Breast Cancer And Its Regulation Of Biological Behavior Of Breast Cancer Cell

Objective: 1.This study was to evaluate the expression of KAI1 in breast cancer and explore its relationship with the clinicopathologic features of breast cancer patients.2.Overexpress KAI1 in human breast cancer MCF-7 cell line and investigate its effects on cell proliferation,apoptosis,migration and invasion.Methods: Part one:1.According to the inclusion and exclusion criteria,30 tissue specimens of benign breast lesions and 65 tissue specimens of breast cancer after radical surgery or modified radical surgery were collected,and the expression of KAI1 was detected by immunohistochemistry.2.The selected tissue specimens of breast cancer after radical surgery or modified radical surgery were grouped according to histological grade,clinical stage,axillary lymph node metastasis,tumor size,patient age and molecular type,the relationship between KAI1 and them is analyzed.Part two:1.MCF-7 cells were divided into three groups: the KAI1 overexpressed group,the control group(transfected with empty vector)and the blank group(no transfection).2.The expression of KAI1 and MMP1 were determined by western blot in these three groups.3.The MTT,flow cytometry,scratch healing and transwell assays were performed to evaluate the biological behavior of the breast cancer cell MCF-7 overexpressing KAI1.4.The data of each group were analyzed by SPSS,version21.0.Results: 1.The IHC positive rate of KAI1 in benign breast lesions is76.7%(23/30),while the positive rate in breast cancer is 21.5%(14/65),p<0.05,statistically significant.2.The expression of KAI1 in 65 breast cancer samples have statistically significant difference with pathological histological grade、clinical stage、Lymph node(p<0.05),While the KAI1 protein expression levels,tumor size,patient age,and molecular classification don’t have a difference(p>0.05).3.western blot method showed that the relative expression intensity of KAI1 and MMP1 in the three groups of cells are different.The MCF-7 cells overexpressed KAI1 by plasmids transfection possess a higher expression of KAI1 than the other two groups.While the expression of the MMP1 protein was lower than that of the other two groups.4.The results of the MTT experiment,flow cytometry,Transwell experimentscratch and scratch healing experiment showed that the cell proliferation rate,apoptosis rate,invasive ability and cell migration rate were different,p < 0.05,statistically significant.The apoptosis rate of MCF-7 cells transfected with KAI1 plasmid were higher than those of MCF-7 cells transfected without KAI1;the cell proliferation rate,invasive ability and cell migration rate of MCF-7 cells transfected with KAI1 plasmid were lower than those of MCF-7 cells transfected without KAI1.Conclusions: 1.The expression of KAI1 in breast cancer is lower than that in benign breast lesions,which is related to histological grade,clinical stage and axillary lymph node metastasis of breast cancer,the results suggest that KAI1 may inhibit the occurrence and development of breast cancer.2.After KAI1 transfection in MCF-7 cells of breast cancer,there were higher levels of KAI1 protein.The effect of the KAI1 gene on MCF-7 proliferation,migration,invasion and apoptosis biology may be related to MMP1.