The Expression Of Reduced Folate Carrier In Osteosarcoma And The Clinical Significance

Objective: to investigate the expressions of reduced folate carrir (RFC) and P-170 in osteosarcoma, to analyze their relationshship with the rate of Tumor necrosis and prognosis, and to study the Mechanisms of MTX resistance. Method: 21 osteosarcomas treated by HD-MTX chemotherapy and surgery in our department of orthopedics , from November 2002 to October 2004, were selected, which were 12 males and 9 females with an average age of 17.76±5.72 years old. RFC and P-170 expression were examined with immunohistochemistry in 42 specimens obtained at biopsy and surgery,and the statistical analysis was used to study the telationship between their expressions and the prognosis. Result: the positive rates of RFC and P-170 were 38.10%(8/21)and 47.62%(10/21) in specimens from biopsy, but 33.33%(7/21) and 71.43%(15/21) in surgery specimens, respectively . The expression's level of P-170 in surgery specimens was significance higher than in biopsy specimens (p=0.001). however, there is no significance between the positive rates of RFC in surgery and biopsy specimens(P=0.756). Furthermore, the expression of RFC was closely correlated with the osteosarcoma prognosis . Conclusion: low expression of RFC in osteosarcoma plays an important role in the mechanism of inherent resistance to MTX , and The level RFC's...