Expression And Localization Of MMP-1 Protein In Human Breast Cancer May Be Related To Clinical Significance

Objective: At present, C hina has become one of the fastest growing incidence of breast cancer in the world, in many large and medium cities in C hina, the breast cancer in female malignant tumors have ranks first, and gradually getting younger. Therefore, the research on exploring the pathogenesis of breast cancer and improving the effect of comprehensive treatment has been one of the focuses in the field of breast cancer.Invasion and metastasis are the malignant signs and features of breast cancer, and also the main cause of death in patients. The degradation and destruction of basement membrane and extracellular matrix, which mainly consist of type IV collagen, laminin and fibronectin, are important steps in the process of tumor metastasis. A variety of protease family such as matrix metalloproteinases, serine protease, cysteine protease may promote the invasion and metastasis of various tumors,and matrix metalloproteinases(MMPs) are one of the most important enzyme families. So far, 28 kinds of MMPs have been identified in humans. O f all the MMPs, MMP-1 is the first vertebrate collagenase purified as a protein and cloned as a c DNA, and is considered the prototype for all the interstitial collagenases. Research shows that MMP-1 can degrade basement membrane and extracellular matrix, and induce endothelial cell hyperplasia, in the process of tumor invasion and metastasis plays an important ro le. But the related research reports, especially about MMP-1 in breast cancer research is few.Our previous study found that breast cancer can be positioned ER protein expression in the nucleus and / or cell plasma membrane, and is closely related to the biological behavior of Expression and localization of ER protein and prognosis of breast cancer.Therefore, the purpose of this study is to understand the MMP-1 protein expression in breast cancer, and the relationship of MMP-1 protein expression with clinical pathological characteristics and investigate MMP-1 role in the process of occurrence and development of breast cancer.Method:1. A total 99 surgery specimens of invasive breast cancer(includingcytoplasm and tumor stroma in 28 cases of ER nuclear(+) breast cancer group, 23 cases of ER slurry(+) breast cancer group, 22 cases of HER-2(3+) in breast cancer group and 26 cases of three negative breast cancer group)were collected from Second Affiliated Hospital of Dalian Medical University between January 2013 to March 2014, all patients were female. The age is 32-86 years old, with average age of 54 years old. All patients were not received any preoperative radiotherapy or endocrine therapy, chemotherapy. In all of 99 cases, 83 cases were non- special invasive carcinoma, 26 invasive breast cancers, and 3 cases of mucinous carcinoma.2. The localization and expression level of MMP-1 protein were examed by using immunohistochemistry and western-blotting, respectively. The relationships of MMP-1 localization and expression level with expressions of estrogen receptor(ER), progesterone receptor(PR), human epidermal growth factor receptor 2(HER-2), and the clinicopatholgical characteristics of breast cancer were analyzed.3. All data were analyzed by SPSS17.0 statistical software. As The comparison of objects is different, according to the situation using respectively ?2 、Spearman correlation analysis, rank sum test(Kruskall-Wallis H test), independent samples T test analysis the measurement date.Values of p<0.05 were considered significant.Results:1. Immunohistochemistry staining results showed that breast cancer cell nucleus, cytoplasm and tumor stromal cells are colour.(1) The rate of MMP-1 was 57.58% in the cancer cells(57/99), the positive expression of cytoplasmic positive expression rate was 62.63%(62/99). MMP-1 nuclear positive expression rate was related with lymph node metastasis status, age, menopause(p<0.05), and was not related with the size, histological grade, clinical and tumor staging.(p>0.05); MMP-1 cytoplasm positive expression was related with lymph node status(p<0.05), clinical stage III + IV positive expression rate(75.86%) was higher than that of I + II(57.14%), but has not statistical significance(p>0.05), and patient age, menopausal status, tumor size, histological grade are independent(p>0.05); The rate of positive expression of MMP-1 in the tumor stromal was 71.72%(71/99), the rate of tumor stromal cells of MMP-1 positive expression and lymph node metastasis status are relative(p<0.05), clinical stage III + IV positive expression rate was higher than that of I + II, histological grade III positive expression of MMP-1 is the highest, but no statistical significance(p>0.05), It has not relevant with patient age, menopausal status, tumor size(p>0.05).(2) MMP-1 expression in three negative breast cancer group has the highest positive rate(76.92%,20/26), followed by ER positive group(73.91%,17/23). Nuclear expression of MMP-1 was highest in the ER positive group(89.29%,25/28). MMP-1 tumor stromal expression in three negative breast cancer(TNBC) group expression was the highest(92.31%,24/26).(3) the nuclear expression of MMP-1 was negatively correlated with K i-67 expression(p=0.000, r=-0.353).A significant positive correlation with the expression of K i-67 and MMP-1(p=0.007, r=0.270).Tumor stromal MMP-1 expression was positively correlated with K i-67(p=0.000 r=0.420).2. Western-blot(1) the amount of MMP-1 expression in TNBC group is highest(33.90 ± 7.56), higher than other groups with statistically significant difference(p<0.05).(2) The amount of MMP-1 expression related to clinical expression、 tumor size and lymph node metastasis, the expression of MMP-1 of tumor diameter of >2 group was higher than the expression of tumor diameter is less than or equal to 2 groups(p<0.05); the expression of clinical stage III + IV group protein content is higher than in group I + II protein expression(p<0.05); group with lymph node metastasis of protein expression amount was higher than that non lymph node metastasis the expression quantity(p<0.05).(3) the expression of MMP-1 protein in K i-67(+) group was higher than that of Ki-67(-) group(p<0.05).Conclusion:1. The expression of MMP-1 protein located in the cytoplasm of breast cancer cells, cell nucleus and cytoplasm in tumor stroma.2. The expression localization in the cytoplasm and expression level of tumor stroma cells of MMP-1 protein in breast cancer are related to poor prognostic factors.3. The expression level o f MMP-1 protein in cancer cell nucleus was related to good prognostic factors of breast cancer.4. MMP-1 protein expression in HER-2(3+) group and TN BC group was obviously higher than that of ER nuclear positive group,sugeest that the MMP-1 protein is associated with poor prognosis of breast cancer patients.