汉黄芩苷对鼻咽癌裸鼠移植瘤模型的放疗增敏作用及其机制研究

Radiosensitization and mechanism of wogonin on transplanted nasopharyngeal carcinoma cell line of 5-8F in nude mice

目的 观察汉黄芩苷对鼻咽癌裸鼠移植瘤放疗的增敏效应，并探讨其与核转录因子NF—KB的关系。方法取低分化鼻咽癌5．8F细胞接种于雌性裸鼠皮下（共接种24只），待肿瘤结节约4—6mm时，将裸鼠随机分为4组，每组6只。分别为对照组、汉黄芩苷组[20mg／（kg·W）]、放疗组、汉黄芩苷[20mg／（kg·W）]联合放疗组。依照各组不同治疗措施处理，定期测量瘤体体积，3周后处死裸鼠，剥离瘤体称重，分别计算各组抑瘤率；并采用RealtimePCR检测瘤体组织中NF—KBmRNA的表达水平。结果汉黄芩苷联合放疗组移植瘤的体积和重量显著下降，相比对照组、汉黄芩苷组及放疗组差异均具有统计学意义（P均〈0．05）；汉黄芩苷联合放疗组NF—KBmR-NA表达水平明显下降，与其他各组相比，差异均具有统计学意义（P均〈0．05）。结论汉黄芩苷能增强鼻咽癌裸鼠移植瘤对放疗的敏感性，其作用机制可能与抑制核转录因子NF—KB的作用相关。

Objective To detect in vivo radiosensitization of wogonin on transplanted nasopharyngeal carcinoma （NPC） in nude mouse, and to explore the relationship between the radiosensitization and expression of nuclear factor-KB （NF-KB）. Methods 5 -8F cells were inoculated subcutaneously in the fight axillas of 24 female BALB/c nude mice. When tumor nodes reached certain size （ range 4 - 6 ram） , the mice were randomly divided into four groups （6 mice for each group）： control group, wogonin group （20 mg/kg, intraperitoneal injection）, radiotherapy group （20 Gy）, and combination group （wogonin plus radiotherapy）. The tumor volume was measured once every three days. Three weeks after treatment, all mice were executed and tumors were removed and weighed. Their tumor inhibitory rates were calculated. Real-time PCR was applied to detect the expression of NF-KB in tumor tissues. Results Both tumor volume and weight of the combination group were less than those of the other three groups respectively （all P 〈 0. 05 ）. Real-time PCR showed that the expression of NF-KB mRNA in the combination group was decreased as compared with those of the other three groups, and the differences were all statistically significant （ all P 〈 0. 05 ）. Conclusion Wogonin may increase radiosensitization of transplanted NPC in nude mice with possible mechanism of down-regulated expression of nuclear factor- KB.