The Expressions Of STAT3, CyclinD1and Ki67in Human Non-small Cell Lung Cancer Tissue And Correlativity Analysis

Objective：To examine the expressions of STAT3(Signal transducerand activator of transcripton3), cyclinD1and Ki67in NSCLC (Non-Small CellLung Cancer) and normal lung tissue, study their relation ship,and to exploretheir possible roles in the tumorigenesis of NSCLC or tumor invasion andmetastasis. Method: Thirty resected tissue samples from patients with NSCLCand twenty normal lung tissues were subjected to immunohistochemicalstaining (Envision) for STAT3, cyclin D1and Ki67. The NSCLC tissues wereobtained from30patients undergoing lung cancer resection at the Departmentof Surgery. No patient had received chemotherapy or radiation therapy beforesurgery. Detailed clinicopathological parameters including age, tumor diameter,stage, lymph node metastasis, and degree of differentiation are as following.There were20males and10females. Their ages ranged from35to76. Thespecimenes whose tumor diameter＞3cm were22compared8specimeneswhose tumor diameter≤3cm. There were15squamous carcinomas and15adenocarcinomas. The metastatic lymph node specimens were14, while16specimens had no nodal metastasis performance. NSCLC tissues that belongdetoⅠ-Ⅱs tage were16and that belonged toⅢ-Ⅳstage were14. Moderatelydifferentiated and well-differentiated tumors were19, poorly differentiatedtumors were11. All the specimens were dealt with formalin fixation, paraffinimbedding and section-cutting. After deparaffinage and hydration, we rinsed the sections with distilled water and soaked them in phosphate buffer saline. Thenthey were subjected to an antigen retrieval procedure by heating. Endogenousperoxidase activity was blocked using3%H2O2solution and nonspecificbinding sites were blocked by incubating with goat serum. The slides wereincubated with appropriate primary antibody (Rabbit anti-STAT3PolyclonalAntibody, Mouse anti-CyclinD1Monoclonal Antibody and Mouse anti-Ki67Monoclonal Antibody). Wait2hours and then wash them with PBS. Thesecond antibody Envision were dropped to incubated. Wait15minutes and thenwash them with PBS. Immunologic reaction was developed using DAB. Theslides were counterstained with hematoxylin, mounted and then observedthrough microscope. Consider the cells whose cytoplasm or nucleus hadbrownish yellow matter as positive cells. The STAT3positive signal was mainlyin cytoplasm. The cyclinD1positive signal was localized in both cytoplasm andnucleus, but predominantly in nucleus but Ki67was mainly in nucleus. Theywere divided into4levels according to proportion of positive cells and colourdepth of each slice. Results:⑴Protein levels of STAT3, cyclinD1and Ki67were significantly increased in NSCLC tissue compared with normal tissue(P<0.01).⑵Overexpression of STAT3, cyclinD1and Ki67wasn’t associatedwith age of onset, tumor diameter, nodal metastasis, tumor differentiation andstages in NSCLC (P＞0.05).⑶There was no significant correlation betweenthe expressions of STAT3and cyclinD1in NSCLC (P＞0.05).⑷There was nocorrelation between the expressions of STAT3and Ki67(P＞0.05).⑸There was also no correlation between the expressions of cyclinD1and Ki67inNSCLC (P＞0.05). Conclusion:⑴The levels of STAT3, cyclinD1, andKi67proteins were higher in NSCLC than in normal lung tissue. Theoverexpression of STAT3, cyclinD1and Ki67might play important roles in thetumorigenesis of NSCLC.⑵There was no association between STAT3,cyclinD1or Ki67overexpression and the age of onset, tumor diameter, lymphnode metastasis, tumor differentiation and stages in NSCLC. It indicates thatthose three proteins have no effct on tumor progression, invasion and metatasis.⑶There was no significant correlation between the expressions of STAT3andcyclin D1in NSCLC.⑷In NSCLC, there was no significant correlationbetween STAT3and Ki67expression. It shows that Ki67participates intumorigenesis of NSCLC through other way but not through STAT3signalingpathway.⑸There was also no correlation between the expressions of cyclinD1and Ki67protein. So they might have no synergistic action with eath other inNSCLC. They might play independent roles in oncogenesis of NSCLC.