PTEN, Galectin-3 And Ki-67 Expression And Significance In The Thymoma

1 Background and purposeThymoma in human tumors is relatively rare in a class of tumors, it comes from the thymus, mainly located in the anterior mediastinum, more common in adults, children, the incidence is rare and no difference in incidence between men and women. Seen under the microscope can be divided into three categories of thymoma:(1) epithelial cell thymoma (2)lymphocytic thymoma epithelial cells (3) lymphocytic thymoma epithelial cells of lymphoid or mixed thymoma. Mostly benign, but still a small number of cases in the clinical performance of evil behavior, such as the pleura, the pericardium cultivation, mediastinal lymph node and lung metastasis.At present,the diagnosis of thymoma is not difficult,according to clinical symptoms and signs in combination with a comprehensive analysis of imaging examination,the basic diagnosis can be made. In the treatment of thymoma mainly complete surgical excision of the combined treatment,n addition to clinically proven tumor metastases can not be removed or shall be timely chest surgery.Is now generally agreed that the prognosis of thymoma and thymoma organization has violated and whether the thymoma combined with other diseases related to pathological classification has nothing to do with.Kondo and other studies have reported,Ⅰ,Ⅱ,Ⅲ,Ⅳpatients with 5-year survival rates were 100%,98%,89%,71%.In recent years,studies have shown that, PTEN,Galectin-3 and Ki-67 in a variety of tumors,development, metastasis and prognosis may play an important role.Studies have shown that there is in the thymoma tissue loss of PTEN expression and Ki-67 overexpression,PTEN and Ki-67 expression was negatively correlated,suggesting that PTEN and Ki-67 in thymoma cells plays an important role in the malignant process, may be the occurrence of the combined effect of the thymoma,the development process. Galectin-3 may be by regulating cell growth,inhibit cell apoptosis and cell adhesion-mediated channels such as in tumor occurrence and development of the process also plays an important role. Previous studies have shown that,Galectin-3 expression level and its intracellular distribution and thyroid cancer,colon,stomach, lung,liver and other cancers exist in relevance. But not yet removed from the protein levels on the abnormal expression of Galectin-3 to study the relationship with thymoma.In this study, by histopathology and immunohistochemistry to detect PTEN, Galectin-3 and Ki-67 expression in the thymoma tissue changes of thymoma in their occurrence and development of the role and significance of the thymoma Early diagnosis and prompt treatment to prevent recurrence and provide a basis for prognosis.2 Materials and methods2.1 Experimental Materials40 cases of thymoma specimens for the First Affiliated Hospital of Zhengzhou University in July 2007-2009 6 menstrual pathologically confirmed surgical resection specimens.22 cases were male and female 18 cases; aged 2 years to 73 years,with an average age of 38 years.All specimens by histopathological examination confirmed thymoma organization and formalin-fixed,paraffin embedding,serial sectioning standby.2.2 Experimental MethodsThe immunohistochemical SP method,PTEN mouse anti-human monoclonal antibody,rabbit anti-human Galectin-3 polyclonal antibody,mouse anti-human Ki-67 monoclonal antibody,SP immunohistochemistry kit and diaminobenzidine (DAB) color kit were purchased, Beijing Golden Bridge Biotechnology Co. Ltd. fir. Steps in strict accordance with SP immunohistochemistry kit instructions. With phosphate buffered saline (PBS) instead of a resistance as negative control.2.3 The results to determineObserve the cells under a microscope with a clearly visible and positioning accuracy of the yellow,brown yellow or brown granules (clear background) positive staining. PTEN protein and Galectin-3 were localized in the cytoplasm,Ki-67 protein in the nucleus.By a pathologist for more than two pairs of immunohistochemical staining to evaluate,in the 400-fold from the Perspective of arbitrary choice five horizons, each horizon count 200 cells,the cells no positive response or number of positive cells< 10% is negative;positive cells the number of>10% is positive. Known for positive film with the positive control. With PBS instead of primary antibody as negative control.2.4 Statistical MethodsApplication of SPSS15.0 for Windows statistical software for statistical processing, with theχ2 test and Fisher's exact probability method to conduct significance test, using Spearman rank correlation for correlation analysis. In order to test the level ofα=0.05.3 ResultsPTEN in 5 cases of normal thymus tissue of all the positive expression, in 16 cases of A+AB thymoma patients,12 patients (75.0%) positive. B1+B2 in 17 cases of thymoma patients, only 5 cases (29.4%) positive. In seven cases of type B3 thymoma,1 patients (14.3%) positive. PTEN Masaoka stageⅠ+Ⅱin patients with positive expression rate (57.7%) was significantly higher than stageⅢ+Ⅳ(21.4%), the difference was statistically significant (P=0.029).Galectin-3 in 5 cases of normal thymus tissue relatively weak, in 16 cases of A+ AB thymoma patients,7 patients (43.8%) positive. B1+B2 in 17 cases of thymoma patients and 14 (82.4%) positive. In seven cases of type B3 thymoma patients,6 patients (85.7%) positive. Galectin-3 in the Masaoka stageⅠ+Ⅱpositive rate of patients (53.8%) was significantly lower than the stageⅢ+Ⅳ(53.8%), the difference was statistically significant (P= 0.012).Ki-67 in five cases of normal thymus tissue expression of basic no case, in 16 cases of A+AB thymoma patients,8 patients (50.0%) were positive. B1+B2 in 17 cases of thymoma patients and 15 (88.2%) positive. In seven cases of type B3 thymoma patients,6 patients (85.7%) positive. Ki-67 in the Masaoka stageⅠ+Ⅱpositive rate of patients (61.5%) was significantly lower than the stageⅢ+Ⅳ (92.9%), the difference was statistically significant (P= 0.034).4 Conclusion(1) PTEN expression in the loss, Galectin-3 and Ki-67 over-expression of thymoma occurrence, development and malignant process was significantly related to detection of thymus tissue PTEN, Galectin-3 and Ki-67 expression of the early thymoma diagnosis and treatment has an important significance.(2) PTEN, Galectin-3 and Ki-67 expression and clinical staging of thymoma and sub-type related to detection of thymus tissue PTEN, Galectin-3 and Ki-67 expression will help to determine the clinical stage of thymoma, the degree of malignancy and recurrence.(3) PTEN and Galectin-3, Ki-67 expression was negatively correlated, PTEN may be through the regulation of Galectin-3 and Ki-67 expression, inhibit invasion and metastasis of thymoma; Galectin-3 and Ki-67 showed a positive correlation between the two In the occurrence of thymoma, development and beginning the process of malignant synergy.(4) Galectin-3 in different phases in different tissues of thymoma, indicating that Galectin-3 involved in the occurrence of thymoma, development, malignancy and metastasis, in order to thymoma in-depth research direction.