The Correlation And Clinical Significance Of The Expression Of VEGF And Nm23 With Angiogenesis In Osteosarcoma

Osteosarcoma (OS) is the most common primary malignant bone tumor inadolescents and young adults, comprising 20% of all such malignancies. Itsbiological behavior is always highly malignant. Its hematogenous metastasisoccurs more frequently and early. The standard therapy of OS is amputationbefore 1970, but the 5-year survival rate of OS is less 10%. Despite recentadvances in multimodality treatments consisting of aggressively adjuvantchemotherapy and wide tumor excision make the 5-year survival rate of OSclimb to 80%, a significant percentage of patients die from lung metastasis.Some papers report that 80 percent of osteosarcoma patients have lungmetastasis in final diagnosis, which is the first cause of death of advancedosteosarcoma. So it is a great significance to research the mechanism ofmicro-metastasis of OS in improving the clinical results of therapy andjudging the prognosis. VEGF makes great function in stimulating the tumorgrowth and making it metastasis, but nm23 can anti-metastasis. Theco-research of VEGF and nm23 in OS is seldom reported.Objective: To investigate the expression and function of vascular endothelialgrowth factor (VEGF) and nm23 and research their relations in osteosarcoma,which provides theoretical foundation for explaining the mechanism ofmicro-metastasis and comprehending the prognosis of OS.Method: From Jan. 1998 to Dec. 2003, 40 osteosarcoma patients treated inthe first affiliated hospital of Jiangxi medical college, with follow-up morethan two years, were selected to enter this study. Specimens of 40 OS werestudied by immunohistochemical S-ABC method to VEGF, CD34 and nm23.The known standard positive specimen from Fuzhou Maixin biological Co.Ltd. was the positive contract, and the negative contract was PPS instead ofVEGF, CD34 and nm23 as the first antibody in this experiment. Expression ofVEGF, nm23 gene is that the cell dyed brown and obvious dense backgrounddying is named positive. And the number of positive cells was counted fromwhich one hundred of cells in high-scope with incompletely randomizedprinciple. When the number of the positive cells are less than 24,theexpression rate is recorded(+),then the number of positive cells are between25-49, 50-74, 75-100, and the expression rates are(++),(+++),(++++)respectively. The high expression of VEGF and nm23 is (+++)to(++++),andthe low expression is(+)to(++). Statistic soft file of SPSS 10.0 for Windowswere used in Statistics analysis. All the enumeration data was analyzed byFisher's exact test and the measurement data was analyzed by student t test.Results: VEGF staining was positive in 37 tumors (92.5%) which theCD34-positive micro-vessels was significantly higher than that inVEGF-negative 3 tumors (P<0.05), and multivariate analysis indicated thatmicro-vessel density (MVD) and VEGF expression were closely correlatedwith patients'poor prognosis as well as metastasis. There was no correlationbetween patient's prognosis and patient's gender, age, the time of illness.nm23 staining was positive in 18 tumors (45%), which was no significancebetween patient's prognosis and the expression of nm23 in statistics.Conclusion: VEGF is a critical angiogenic stimuli which stimulatesangiogenesis, tumor growth and metastasis in osteosarcoma, the microvesseldensity and VEGF expression can function as two independent prognosticvariables in osteosarcoma. But nm23 is nonmetastasis suppressor inosteosarcoma, which expression can't play important role in prognosis ofosteosarcoma.