Expression Levels Of RASSF1A And KRAS In Breast Cancer Tissues And Their Clinical Significance

Objective:At present,the morbidity and mortality of female breast cancer in our country are increasing year by year.For the treatment of this disease,Chinese women tend to choose surgical resection of the breast,supplemented by postoperative radiotherapy,chemotherapy and endocrine therapy.Therefore,breast cancer not only brings physical health damage to women,but also reduces the quality of life of women.In recent years,with the increasing popularity of molecular biology,more and more proto-oncogenes and anti-cancer genes related to breast cancer have been discovered by scholars and applied to clinical work.It brings new hope for the treatment of breast cancer.The purpose of this study was to summarize the expressions of RASSF1A and KRAS in BC and the corresponding para-carcinoma tissue,and to explore the correlation between the expressions of RASSF1A and KRAS and their clinicopathological characteristics,so as to lay a foundation for the research on the pathogenesis and treatment of breast cancer.Methods:The postoperative histopathological specimens of a total of 78 breast cancer patients from January 2015 to July 2016 were collected and screened in the thyroid and breast hernia surgical ward of HePing branch of the North China Theater General Hospital.The expression levels of RASSF1A and KRAS in breast cancer tissues and para-carcinoma tissue(within 5cm of the tumor edge)were detected by immunohistochemical staining,and the relationship between the expressions of RASSF1A and KRAS and the clinicopathological characteristics was analyzed.Results:Immunohistochemical results showed that:1.RASSF1A was highly expressed in the cytoplasm and some nuclei of para-carcinoma tissue,while KRAS was highly expressed in the cytoplasm and a few nuclei of cancer tissues.2.The expression level of RASSF1A in para-carcinoma tissue(76.92%)was significantly higher than that in breast cancer tissues(34.62%),and the difference was statistically significant(χ~2=28.30,P<0.05).3.RASSF1A in different age,maximum tumor diameter,ER,PR,HER-2expression differences of no statistical significance(P>0.05),and expressed in different TNM stages:stageⅠexpression rate(70.58%)was higher thanⅡexpression rate(30.56%)thanⅢexpression rate(16.00%),the difference statistically significant(χ~2=13.81,P=0.001).The expression rate without lymph node metastasis(45.10%)was higher than that with lymph node metastasis(14.81%),the difference was statistically significant(χ~2=7.153,P=0.007).The expression rate in ki-67<15%(56.52%)was higher than that in ki-67>15%(25.46%),and the difference was statistically significant(χ~2=6.916,P=0.009).4.There was no statistically significant difference in KRAS expression at different ages,maximum tumor diameter,TNM stage,ER,and PR(P>0.05),while the expression rate without lymph node metastasis(74.51%)was lower than that with lymph node metastasis(96.30%),and the difference was statistically significant(χ~2=4.307,P=0.038).The expression rate of negative HER-2(59.01%)was lower than that of positive HER-2(91.07%),with statistically significant difference(χ~2=8.905,P=0.003),and the expression rate of ki-67<15%(60.87%)was lower than that of ki-67 15%(90.91%),with statistically significant difference(χ~2=8.002,P=0.005).5.RASSF1A expression was negatively correlated with KRAS expression in breast cancer tissues,and the difference was statistically significant(φ=-0.573,χ~2=22.532,P<0.001).Conclusion:The expression level of RASSF1A was down-regulated in breast cancer tissues,while the expression level of KRAS was up-regulated,which was negatively correlated with each other and may have antagonistic effects.As an anticancer gene,RASSF1A may be associated with the occurrence and development of breast cancer.As a proto-oncogene,KRAS may be associated with the proliferation of breast cancer cells and can be used to determine the prognosis of patients.Combined detection of RASSF1A and KRAS expression and further study of their molecular mechanism may provide new ideas for early diagnosis,targeted treatment and prognosis of breast cancer.