Significance Of The Expression Of TP And MVD In Astrogliomas

Objective: Astrogliomas are common tumors of neuroepithelial tissue. The tumors develop from astroglia cells of white matter or gray matter in central nervous system. They can be divided into two main categories: lower grade astrocytoma (LGA)/ the well-differentiated (WHO grade I—II) and high grade astrocytoma (HGA)/ the undifferentiated (WHO grade III-IV). According to WHO 2000 histological classification of tumors of nervous system, astrogliomas can be divided into 6 subtypes. Astrogliomas prognosis depends on histological differentiation, pathological type, invaded site and surgical removal. Astrogliomas occur and develop under multiple factors, thereinto tumor angiogenesis plays an important role in tumors' growing, infiltrating and transferring, which not only realizes oxygen and nutrient supply for tumorous tissue, but also provides a short cut for tumor cell dispersing and transferring. Tumor angiogenesis depends on in-tumor expressing of tumor angiogenesis factors (TAFs) and angiogenesis inhibitory factors such as acid fibroblast growth factor (aFGF), basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), angiogenin, etc. Thymidine Phosphorylase (TP) is a tumor cell growth factor found and paid much attention to in recent years, whose structure and function are similar to that of platelet-derived endothelial cell growth factor (PD - ECGF), therefore it is also named tumor related angiogenic factor, and it may accelerate the growth and transfer of cancer cells through angiogenesis. In recent years, research shows that the proportion of TP in mammary cancer, bladder cancer, ovarian carcinoma, gastric carcinoma and uterus carcinoma has increased, and that this is associated to microvascular density(MVD). However, TP is at present seldom involved in cerebral tumor research. This experiment is designed to probe into TP expression in cerebral astrogliomas, analyze the relation between TP expression and microvascular density (MVD) and pathologic grading, and discuss whether the expression can be taken as the reference benchmark of pathologic grading and prognosis judging.Methods: This experiment is based on the 208 cases of cerebral astroglioma between 2003 and 2005 provided by pathology department, Affiliated Hospital of North Sichuan Medical College. 60 cases are random sampled from computer, and by referring to corresponding pathological sections, 50 cases with distinct hemorrhagic putrescence are removed through light microscope observation, which are not suitable for preparing immuno-histochemical specimens. Normal cerebral tissue autopsy specimens of 5 cases are recorded with respect to histologic type and pathologic grades. For rat anti human monoclonal TP antibody, 1 mastadenitis specimen is chosen (for positive control), and for rat anti human monoclonal CD34 antibody, 1 tonsillitis specimen is chosen (for positive control). Each specimen is cut into 3 pieces. TP and CD34 expressions of the specimens are detected using immuno-histochemical technique SP method. According to percentage of positive cells and tinctorial degree, TP expression result can be classified into TP(+) and TP(—). MVD is calculated by means of CD34 dye marking, and relations between TP and pathologic grading, MVD and pathologic grading, TP and MVD are analyzed by statistics methods..Results: 1. TP expression of 5 normal cerebral tissue specimens are negative (—). 2. TP expression of HGAs (WHO grade III～IV) is significantly higher than LGAs (WHO grade I～II) (X~2=20.07,P<0.05).3. MVD of HGAs (WHO grade III～IV) is evidently higher than LGAs (WHO grade I～II) (t = 7.2,P<0.05).. 4. TP/PD-ECGF expression and MVD are directly correlated (r=0.692,P<0.05)Conclusion: Expressions of TP and MVD are closely connected with astroglioma malignancy, and the said expressions are directly correlated. TP may accelerate malignantly the growth of astroglioma through tumor angiogenesis, and affect prognosis. TP and MVD can be used as the reference benchmark of pathologic grading and prognosis judging of astroglioma . The function mechanism of TP can be further studied so as to find new ways for chemical treatment of astroglioma .