NS398对放射抗拒食管癌裸鼠移植瘤的放射增敏作用

目的研究COX-2抑制剂NS398对放射抗拒食管癌细胞裸鼠移植瘤的放射增敏作用。方法采用食管癌细胞悬液裸鼠皮下接种法建立裸鼠移植瘤模型,比较食管Eca109细胞和放射抗拒Eca109R50Gy细胞(接受总剂量50Gy照射)的致瘤能力。选取接种Eca109R50Gy细胞荷瘤裸鼠,随机分为NS398组、放射组、NS398+放射组和对照组。在干预的14d中记录移植瘤体积、重量,计算各组肿瘤抑制率和NS398的放射增敏比值(E/O)。结果 Eca109R50Gy细胞比Eca109细胞裸鼠体内致瘤能力高出40倍。NS398+放射治疗能显著抑制裸鼠移植瘤的生长,体积缩小和瘤重减轻最为明显(P<0.05)。1.5mg/kg NS398的放射增敏比值E/O=1.61(>1.4)。结论 NS398对人食管Eca109R50Gy细胞裸鼠移植瘤具有放射增敏作用,其中更深入的信号传导机制值得进一步研究。

Radiosensitization effect of cyclooxygenase-2 inhibitor NS398 on radioresistant esophageal cancer cell xenografts in nude mice

Objective To investigate the radiosensitization effect of cyclooxygenase-2 inhibitor NS398 on radioresistant esophageal cancer cell xenografts in nude mice.Methods The model of xenograft tumor was established by subcutaneous inoculation of cell suspensions into the nude mice.We compared the tumorigenetic ability between esophageal Eca109 cells and Eca109R 50 Gy cells(which received a total irradiation dose of 50 Gy).The Eca109R 50 Gy cell-bearing nude mice were divided randomly into 4 groups: NS398 treatment group,radiation group,NS398+radiation group and the control group.The volume and weight change of tumors were recorded during the 14 days of intervention.The tumor inhibition rate and radiosensitization ratio(E/O) were calculated.Results Eca109R 50 Gy cells displayed 40 times higher tumorigenetic ability than Eca109 cells in vivo.The treatment of NS398 plus radiation could significantly inhibit the growth of Eca109R 50 Gy cell nude xenografts,particularly with the most obvious decrease of tumor volume and weight(P<0.05).The E/O of 1.5 mg/kg NS398 was 1.61(>1.4).Conclusion NS398 could enhance the radiosensitivity of radioresistant Eca109R 50 Gy cells in vivo,and more in-depth signal conduction mechanisms need further study.