The Expression And Significance Of E-cadherin And Vimentin Of Epithelial Mesenchymal Transition In Breast Phyllodes Tumor

Objective: By observing the expression of E-cadherin and vimentin in different types of phyllodes tumor and fibroadenoma, we study the mechanism of phyllodes tumor whether involve in epithelial mesenchymal transition. And explore the distinction and connection between fibroadenoma and phyllodes tumor, the biological characteristics of every types of phyllodes tumor.Methods: We selected 50 breast phyllodes tumor samples from 2005 to 2015 in Pathology Department of Southwestern Medical University Affiliated Hospital. All patients who did not accept any drug treatments before operation had completed related auxiliary examination: ultrasound, mammography, thick needle puncture. Their lumps all were one-stage resection and classified as benign, borderline and malignant phyllodes tumor according to pathological nuclear division diagnosis index of pathological report standard type from WHO. At the same time 30 breast fibroadenoma cases were selected as control. All samples were divided into 4 groups: group A 30(benign PTB), group B 12(borderline PTB), group C 8(malignant PTB) and group D 30(breast fibroadenoma). Firstly, hematoxylin and eosin(HE) staining of four groups was used to observe histological differences, immunohistochemistry was used to detect the expression of epithelial marker E-cadherin and mesenchymal mark vimentin, which are the important related molecules of epithelial mesenchymal transformation. Then we scored respectively according to the staining degree and positive cells rate which were detected in high magnification microscope(×400) and selected randomly 10 visual fields according to the universal classification standards from literature records. The results of immunohistochemistry are respectively analyzed and valued by average integral optical density(IOD), in order to determine the expression of each protein in the cell and the degree within the epithelium and stromal elements. We recorded the results of semiquantitative analysis and analysed the expression of EMT markers, E-cadherin and vimentin, in different types of phyllodes tumor and fibroadenoma. Whether the development of tumors is involved in epithelial transformation process, and epithelial mesenchymal transformation process will be exacerbated with development of tumor malignant degree.Results:(1)HE staining: microscopically visible tissue of benign PTB showed obvious lobular structure, fracture structure, tubular glands. Stroma were arranged mussily, the proportion of glands and stroma were unbalanced. The stromal overgrowth and hyperplasia were greater than fibroadenomas and cell atypia was not obvious, less nuclear mitoses could be visible.The breast fibroadenoma showed hyperplasia of fiber stromal and glandular epithelium, stroma was loose and a large number of fiber cells and myxoid stroma were apparent, but hyperplasia degree was lower compared with phyllodes tumor. The malignant PTB showed stromal overgrowth, nuclear division>10/10 HPE, abnormal cell and the unclear boundary. The stromal cells in borderline PTB were moderately distributed, and the extent of marked hyperplasia was between benign and malignant PTB, atypical cells were moderate,nuclear division 5-9/10 HPE. The cell distribution was not uniform, no necrosis, and the boundaries with surrounding tissues were partly clear but partly unclear.(2)Immunohistochemistry results: the positive expression of E-cadherin and vimentinin could be detected in benign, borderline, malignant PTB and breast fibroadenoma. And the expression of E cadherin showed markedly positive expression in benign PTB and fibroadenoma, the IOD was 252413±402 in benign PTB and 298100±456 in fibroadenoma. There was no significantly statistical difference compared with eath other(P>0.05). The positive expression decreased significantly with the development of tumor malignant degree. IOD value was 158950±285 in borderline PTB and 92157±197 in malignant PTB, and the difference was statistically significant compared with benign PTB and fiberadenoma(P<0.05). The brown positive expression of vimentin in benign PTB and fibroadenoma was weak, IOD was 78314±308 in benign PTB and 81340±456 in fibroadenoma. There was no significantly statistical difference compared with eath other(P>0.05).The degree and scope of expression were significantly increased with the malignant degree becoming worsen, and IOD value 149505±785 in borderline PTB and 291557±317 in malignant PTB. The differences were statistically significance compared with benign PTB and fibroadenoma(P<0.05). All datas were shown by mean±standard deviation( sx ±). The results showed that expression of E-cadherin and vimentin, as the important molecular markers of epithelial mesenchymal transitionin, in different categories of phyllodes tumor was statistically significance,which indicated that the tumorigenesis process may be associated with different degree of epithelial mesenchymal transition process. The difference of the two protein in fibroadenoma and benign phyllodes tumor was not statistically significant, indicating that the process and mechanism of the two tumors may be correlated.Conclusions: 1. With the malignant degree of phyllodes tumor developed, the expression of E-cadherin decreased and vimentin increased. The mechanism of phyllodes tumor may be involved in epithelial mesenchymal transformation, and with the malignant degree worsen, epithelial mesenchymal transition degree was increased. 2.The pathological features of breast fibroadenoma and benign breast phyllodes tumor is very similar, both pathogenesis of and process may be correlated.