The Research On The Relationship Between Protein Expression Of Cullin7and The Metastasis In Breast Cancer

Background: Breast cancer has become one of the the most common malignanttumor of female worldwide, which is an important cause of female death.Breastcancer recurrence and metastasis are the main reason that casuse the death of breastcancer patients. The treatments of metastatic breast cancer are very tough and theprognosis is very poor. In recent years, screening on metastasis related genes of breastcancer has become a popular research field. Cullin7gene is screened to be a candidategene associated with metastasis of breast cancer in our preliminary experimentalstudy,which belongs to cullin gene family. In this study, we used theimmunohistohemical method to research in the protein expression in normal breasttissues, benign breast tumor, primary focas and axillary lymph node metastasis tissueof breast cancer, we also analyzed and studied in the relations between expression ofcullin7and metastasis of breast cancer.Objective: We studied the protein expression of cullin7in normal breast tissues,benign breast tumor, primary focas and axillary lymph node metastasis tissue of breastcancer.We explored the differential protein expression,clinical pathological fators ofpatients of breast cancer and the associated factors of fomation,developent,metastasisof breast cancer. We convinced that Cullin7gene is the associated candidate gene inthe level of immunohistochangmistry（IHC）.Methods and Results:1) We collect surgical specimens of breast cancer surgery in Guangzhou TumorHospital, during July2011to July2013,which includingthe normal breast tissues, benign breast tumor, primary focas and axillary lymph node metastasis tissue of breastcancer as the experimental group.This experimental group included13cases ofnormal breast tissue,13cases of adjacent normal breast tissue from benign tumors,20cases of benign breast diseases, including breast adenosis, fibroadenoma,intraductal papilloma, etc.,68cases of the primary focas of breast cance, including56cases of non-specific invasive ductal carcinoma,12cases of a special type of invasiveductal carcinoma （7cases of medullary carcinoma, mucinous adenocarcinoma fivecases）,32cases of axillary lymph node metastasis.TNM staging system based on the7thedition PTNM staging of breast cancer,which enacted by the International UnionAgainst Cancer and the American Cancer Association in2010. Routine pathologicaltissue examination（HE staining） is to define the protein expression of the histologicaltype, pathological features （degree of differentiation and lymph node metastasis） andclinical staging. Patients were all female, within range of37to66, average age of46.4year-old, median age of47years old. They devides into37cases of pre-menopausalbreast cancer patients and31cases of postmenopausal breast cancer patients,whichcan also devide into stage I:21cases, stage II:20cases, stage III27cases.35cases ofpatents have lymph node metastasis and33of then haven’t lymph node metastasis.All the patients were treated without chemotherapy, radiotherapy and endocrinetherapy.2)We used the immunohistochemistry SP method to test protein expression ofcullin7normal breast tissue in, benign breast tumors, breast invasive ductal carcinoma,axillary lymph node metastases of breast cancer, the analysis the differences ofprotein expression of cullin7between all the selected tissues,We also analysisrelationship of cullin7protein among age of the patients, menopausal status, tumorsize, number of axillary lymph node metastasis, clinical stage, histological type,histological grade and ER, PR, Her-2. X2test is used to analyze the differenct proteinexpression differences of cullin7in breast tissues; Spearman correlation is used inanalysiscorrelation test. P <0.05was considered statistically significant.Results：1.13cases of normal breast tissue are mainly（-） in cullin7expresssion.20case ofbenign breast tumors are （+） in cullin7expression.68cases of breast cancer tissue, mainly between （+）⁺⁺ in cullin7expresssion.32cases of axillary lymph nodemetastasis tissue are mainly between （++）⁺⁺⁺in cullin7expresssion.（-）⁺ judged to be weakly positive expression （cullin7protein low expression）,while（++）⁺⁺⁺ judged to be strong expression （cullin7protein high expression）.The strongly positive expression rates cullin7of protein were:0,30.0%,55.9%,78.1%in the group of normal breast tissue, benign breast tumor group, infiltratingductal carcinoma and axillary lymph node metastasis group. Strong expression ofcullin7protein difference between the groups of normal breast and benign breasttumor, between the groups of the normal mammary gland and frimary focus of breastcancer,between the groups of normal mammary gland and axillary lymph nodemetastasis of breast cancer, between the groups of benign breast tumors and breastinvasive ductal carcinoma, between the groups of benign breast tumors and negativelymph node metastasis of breast cancer, between the groups of infiltrating ductalcarcinoma and axillary lymph node metastasis of breast cancer were all statisticallysignificant （p <0.05）. That groups of lymph node metastases of breast cancercompared with the other groups, protein expression of cullin7difference werestatistically significant （p <0.05）.2. The expression of cullin7in breast cancer was significantly associated withhistology grade and axillary lymph nodes（p <0.05）, but The expression of cullin7inbreast cancer was not significantly associated with postmenopausal, tumor size,pathological type and clinical stage（p>0.05）.3. Cullin7protein in breast cancer tissues were significantly negatively correlatedwith ER （p<0.05）, but with the PR, C-erbB-2is not related （p>0.05）. It also suggeststhat breast cancer protein expression cullin7poor endocrine therapy.Conclusion:1. The protein expression of cullin7in breast cancer was significantly higher thanbenign breast tumors and normal breast tissue. It suggested that the high expressionof cullin7may be involved in the occurrence and development of breast cancer.cullin7can be valuabled as the biomarkers to the distinguish between benign andmalignant breast tissue.2. the expression of cullin7in breast cancer was significantly associated with histology grade and axillary lymph nodes,while The expression of cullin7in breastcancer was not significantly associated with postmenopausal, tumor size,pathological type and clinical stage.3. The strongly positive expression rate of cullin7protein in lymph nodemetastasis group was significantly higher than other groups.And in the clinicalpathology analysis, strong expression rate of cullin7protein in breast cancer patientswith lymph node metastasis was significantly higher than those without lymph nodemetastasis of breast cancer groups. It suggested that cullin7might be have positiveinfluence in invasion and metastasis of breast cancer.Cullin7may be used ascandidate genes related to metastasis of breast cancer.4. Cullin7protein in breast cancer tissues were significantly negatively correlatedwith ER （P <0.05）, but not related with the PR, C-erbB-2（P>0.05）. It also suggeststhat the endocrine therapy may not work well in the patient with the higherexpression of Cullin7protein5. Detecting loss of heterozygosity by exome sequencing technology to screeningcandidate genes related to metastasis of breast cancer many be realiability.