Clinicopathological Significance Of Bmi-1and Mel-18Expression In Breast Cancer

The breast cancer of female patients is the most important cause of death.In China, it tends to be a younger age and enlargement.In late stage, it is often accompanied by recurrence and metastasis, therefore, timely diagnosis and treatment, give the best treatment options to improve the survival rate of patient with breast cancer is self-evident.Today, the life science has been lots of discoveries, as the rise of molecular biology techniques, the diagnosis and treatment of breast cancer have been a solution and the prevention of cancer is possible.It has become possible to seek etiology and pathogenesis of breast cancer at the mRNA and protein levels.The understanding of the biology of breast disease is deepening, unprecedented changes taking place,and its effective biological has been a research focus.Bmi-1and Mel-18in breast cancer are mutually antagonistic.Bmi-1play a role of an oncogene,but Mel-18is a tumor suppressor gene.Both of them are involved in the occurrence of cells senesecence,and it is rarely reported about Bmi-1and Mel-18in breast cancer research.ObjectiveTo study and explore the expression of Bmi-1and Mel-18in breast cancer tissue, benign breast tumor tissue and normal breast tissue at mRNA and protein level, and investigate their correlations.Further more,the relations of their expressions with clinical and pathological features are analyzed.MethodsThe experimental set up three experimental groups, namely breast carcinoma tissue group(40cases), breast benign tumor group(20cases), normal breast tissue group(20cases). The gene and protein expression in all tissues were determined by RT-PCR and immunohistochemical method, respectively. The Bmi-1and Mel-18expression ststus were analyzed at gene and protein level. And to erplore age, menopausal status, tumor size, histological grade, lymph node metastasis, clinical stage, clinical pathological factors contact of the two mammary cancer patients. The date was respectively check with one-way analysis of varianc(ANOVA),Independent sample T-test,Spearman rank correlation, Chi-square test. The software SPSS17.0was applied to analyse the data.ResultsThe mRNA and protein levels of Bmi-1was significantly higher in breast cancer than that in benign tumors of breast and normal breast tissue (all P<0.05), and that in normal breast-tissue and benign tumors existed significant difference(P<0.05). The mRNA and protein levels of Mel-18was significantly lower in breast cancer than that in benign tumors of breast and normal breast tissue (all P<0.05),but that in normal breast tissue and benign tumors was no significance difference (P>0.05).The mRNA and protein expression of Bmi-1and Mel-18was negatively related in breast cancer(respectively r=-0.317, P=0.023; r=-0.413, P=0.008).The mRNA and protein levels of Bmi-1and Mel-18was closely related to lymphatic metastasis and clinical stages(all P<0.05), but was irrelevant to patients’age, tumor size, postmenopausal status and histologic classification (all P>0.05)Conclusion1. Bmi-1was highly expressed but Mel-18is abnormally low expression in breast cancer tissue, both of which are involved in malignant transformation in mammary cancer.2. The joint detection of two indicators of Bmi-1and Mel-18may contribute to breast prevention,diagnosis and treatment, it is possible to become important biological markers.