丁酸钠抑制人喉癌裸鼠皮下移植瘤的实验研究

Inhibitory effect of sodium butyrate on human laryngeal carcinoma xenograft model in nude mice

目的研究丁酸钠对人喉癌裸鼠皮下移植瘤生长的抑制作用,探讨其作用机制。方法将人喉癌细胞株Hep-2细胞接种于12只裸鼠皮下,建立喉癌移植瘤模型。分为实验组和对照组,每组6只,分别给予丁酸钠和磷酸盐缓冲液(PBS)治疗4周。治疗过程中定期测量肿瘤大小及裸鼠体质量,于治疗结束时取肿瘤组织切片进行HE染色、电镜观察、TUNEL标记及免疫组化S-P法检测Ki-67、survivin蛋白表达情况,取心、肝、肺、脾、肾等组织切片进行药物毒性评估。结果治疗组肿瘤体积明显小于对照组,肿瘤组织内坏死面积增大,细胞凋亡率显著增高,Ki-67核抗原、survivin蛋白表达水平降低。治疗过程中裸鼠生长良好,无明显毒性反应。治疗结束时,心、肝、肺、脾、肾组织切片光镜下检查未见异常。结论丁酸钠对人喉癌裸鼠皮下移植瘤有明显的生长抑制作用,其机制可能与抑制survivin表达而诱导细胞凋亡及抑制Ki-67表达有关。治疗剂量的丁酸钠对裸鼠心、肝、肺、脾、肾等组织无毒性。

Objective To study the inhibitory effect and its mechanism of sodium butyrate on human laryngeal carcinoma in nude mice. Methods Human laryngeal carcinoma cell line Hep-2 was seeded in the subcutaneous layer of 12 nude mice to built laryngeal carcinoma xenograft model. Then they were randomly and equally divided into 2 groups. Sodium butyrate was given in experimental group while phosphatic-buffered saline （PBS） was used in control group for 4 weeks. Tumor size and body weight of the mice were measured at regular time-intervals. The tumor, heart, liver, lungs, spleen and kidneys were removed at the end of treatment. Tumor sections were examined by electronic microscopy. TUNEL method and immunohistochemical S-P method were used for detecting the expression of Ki-67 nuclear antigen and survivin protein. The heart, liver, lung, spleen and kidney sections were examined after HE staining for assessment of toxicity. Results In experimental group, the volume of tumors was reduced, the area of necrosis in tumors was widened, the apoptotic rate was increased obviously and the expression level of Ki-67 nuclear antigen and survivin protein was decreased as compared with control group. During treatment, all the nude mice grew well and there were no toxic reactions. At the end of treatment, there were no abnormal changes in heart, liver, lung, spleen and kidney sections examined under light microscope. Conclusion Sodium butyrate can significantly inhibit the growth of human laryngeal carcinoma xenograft in nude mice. Its mechanism may be related to the apoptosis in tumor cells by inhibiting the expression of survivin protein and Ki-67 nuclear antigen. There is no toxicity to heart, liver, lungs, spleen and kidneys at a treatment dose of sodium butyrate.