Study the relationship between the expression of MRP and the radiosensitivity of primary lesions of nasopharyngeal carcinoma

Objective: To study the relationship between the expression of multidrug resistance-associated protein (MRP) gene in nasopharyngeal carcinoma (NPC) and the radiosensitivity of primary lesions of NPC. Methods: Total 51 cases of NPC were analyzed retrospectively, who were treated by radiotherapy between January 1, 1999 and December 31, 2000 in our department, including the cases of pure radiotherapy and chemotherapy after radiotherapy. Using immunohistochemiscal S-P method, the expression of MRP in NPC was detected, and the relationship with the radiosensitivity of primary lesions of NPC was analyzed. Results: The rate of positive expression was 68.63% (35/51) in NPC, and there were significant difference between T stages (P<0.05), but no significant difference with radiosensitivity of primary lesions of NPC (P>0.05). Conclusion: There is a higher expression of MRP in NPC, but it has no relationship with radiosensitivity of primary lesions of NPC. So MRP can not be regarded as the predictive marker of radiosensitivity of primary lesions of NPC.