The Expression And Significance Of Mfn2 And ER-beta In In Breast Infiltrating Ductal Carcinoma

Objective: Breast cancer is the malignant tumors of mammary epithelium. The growth process is closely related with the expression of many oncogenes and anti-oncogenes. Hyperplasic suppress gene(hyperplasic suppress gene, HSG), also known as mitochondrial fusion protein-2(mitofusin-2, mfn-2), had effects of significant growth inhibition and apoptosis induction on various tumor cell lines. It is one of novel anti-oncogenes. Research has confirmed from the molecular biological level mfn2 Ras-ERK signaling pathways negatively regulated by inhibiting cell proliferation and metastasis of breast cancer, suggesting that mfn2 May play an important role in the development and progression of human cancer. It is well known that about 70% breast tissue expression of ER-beta, many expressing breast cancer ER-alpha and ER-beta. Some studies have shown that, ER-beta plays a suppressor role in most cases, its absence can promote the development of breast cancer. Our previous study found that ER-beta expression plasmid transfected MCF-7 cells can inhibit the proliferation and metastasis, mfn2 expression plasmid was transfected MCF-7 cells effectively inhibited E2-induced migration capabilities improvement, also found that ER-beta by mfn2 inhibited E2-induced MCF-7 expression of cell proliferation and metastasis. This experiment from the overall level to observe the relationship between the two, further confirms previous research work.Methods: The samples were randomly selected from January 2008 to December in postoperative patients with breast cancer in 95 cases in the fourth Hospital of Hebei Medical University. All of the patients were women, ages 31~88 years. Each patient was not suited for chemotherapy, radiotherapy and hormonal treatment. All slices were classified in accordance with the WHO histological classification of tumors of the breast, grading standards(2012). 95 cases were breast infiltrating ductal carcinoma, of which 13 cases were histologic gradeⅠ, 63 cases were gradeⅡ, 19 cases were grade Ⅲ. According to AJCC TNM staging of breast cancer standard(2009 Edition), 12 cases had stageⅠ, 69 cases had stageⅡ, and 14 cases had stage Ⅲ. Besides taking normal ductal epithelial tissues(primary tumor >5cm are taken from the margin of normal breast tissue and pathologically) 30 patients as controls. Immunohistochemical methods were taken to detect the tissue expression of ER-beta and mfn2.Statistical methods using χ 2 test and variable correlation analysis.Results:1 The expression of mfn2 and ER-beta in breast infiltrating ductal carcinoma tissues was significantly lower than in normal breast ductal epithelium tissues(P <0.05), both statistically significant difference.2 There was no statistical difference between the group(older than 50 years) and the group(younger than 50 years) in the mfn2 and ER-beta expression(P >0.05).3 Mfn2 and ER-beta expression in histology and pathological grading of grade Ⅰ, Ⅱ, Ⅲ of the three groups with the decrease of the degree of differentiation between both positive expression rate of decline(P <0.05), a statistically significant difference.4 Mfn2 and ER-beta expression in lymph node involvement, 0, 1-3, ≥ 4 groups of three with the increase of lymph node involvement, the positive expression rate of decline(P <0.05), a statistically significant difference.5 The expression of mfn2 and ER-beta was not correlated with TNM staging of stage(P >0.05).6 There was no statistical difference between the bigger tumors(>2cm in diameter) and the smaller tumors(≤ 2cm in diameter) in mfn2 and ER-beta expression(P >0.05).7 The correlation of mfn2 and ER-beta expression in breast infiltrating ductal carcinoma: mfn2 and ER-beta expression is positively correlated in 95 cases of breast infiltrating ductal carcinoma.Conclusions: mfn2 and ER-beta expression in normal breast ductal epithelium tissues were significantly higher than those in breast ductal carcinoma tissues. Mfn2 and ER-beta expression was negatively related to status of lymph node involvement and histologic grade in breast infiltrating ductal carcinoma tissues. The expression of mfn2 in breast infiltrating ductal carcinoma tissues is positively correlated with the ER-beta expression. The positive expression of mfn2 and ER-beta was not correlated with patient age, tumor diameter and TNM stage. The positive expression of both genes was decreased with the increased malignancy of breast cancer and lymph invasion, suggesting that the expression deletion of both genes promoted the invasion and metastasis of breast cancer. The lack expression of both genes was associated with poor prognosis in breast cancer.