Expression Of Survivin In Pancreatic Cancer And Its Correlation To Expression Of Bcl-2

Objectives: Pancreatic cancer is a devastating cancer disease due to its biologically aggressive behavior. Most pancreatic cancers progressed invasion to the peripheral tissues and metastasis to the lymph nodes or distant organs. These characters induce early recurrence and cancer death. Pancreatic cancer is associated with very poor prognosis, with 5-year survival rates ranging from 0 to 8%.Therefore, understanding of the pathogenesis of the pancreatic cancer would be necessary for early diagnosis and better treatment.The inhibitor of apoptosis protein (IAP) is a member of the widely-expressed gene family of apoptosis inhibitors. It can inhibit apoptosis induced by a variety of stimuli and plays a critical role in the physiologic activities of cells. Survivin is a recently-characterized gene, a member of the IAP family, and has a close relation between anti-apoptosis and tumors. Overexpression of survivin has been reported to play an important role in the development and progression of pancreatic cancer.In this study, we investigated the relationship between the expression of survivin in patients with pancreatic cancer and the expression of Bcl-2 in order to provide a theoretical basis for the prevention, diagnosis, and treatment of pancreatic cancer.Methods: Ten samples from normal pancreatic tissue and 42 samples from pancreatic cancer were collected. Normal pancreatic tissues were obtained from autopsy specimens in Department of Anatomy, Medical College, Wuhan University, and their mean age was 49.3 years (range, 33-78). Pancreatic cancer samples were obtained from surgically-resected specimens in Zhongnan Hospital, Wuhan University. All these cancers were diagnosed pathologically.Fixed in routinely-processed formalin and then embedded in paraffin, 4 m thick sections were prepared from the cut surface of blocks at the maximum cross-section. For morphological analysis, the sections were routinely stained with hematoxylin and eosin. Immunohistochemical staining for survivin and Bcl-2 antigen was made by the standard streptavidin/peroxidase (SP) technique. By using immunohistochemistry, Survivin andBcl-2 expression were measured in tissue specimens from 42 pancreatic cancers and 10 normal pancreases.The positive section was used as a positive control. As a negative control, PBS was used instead of the primary antibody for survivin and Bcl-2.Results: No Survivin expression was detectable in normal pancreases,while Survivin expression was detectable in 34 of 42 pancreatic cancers (81.95%).Correlation was found of the expression Survivin with the differentiation and staging of the pancreatic cancers (staging of the pancreatic cancers: positive rate( I - II )30.8% vs (III-IV)62.5%; high differentiation 22.2% vs middle or low differentiation 58.3%) P<0.05 r=0.31K 0.361.Survivin positive cases were strongly associated with Bcl-2 expression ( 28/30 versus 6/12 P<0.05).Conclusion: These findings suggested that overexpression of Survivin play a crucial role in the origin and development of pancreatic cancer, and correlate with the expression of Bcl-2,so the Survivin expression can be used as a prognostic factor.