放疗前后食管鳞状细胞癌组织中Fas和Survivin蛋白的表达

Expression of Fas and Survivin in Esophageal Squamous Cell Carcinoma before and after Radiotherapy

目的:探讨食管鳞状细胞癌术前放疗前后,Fas和Survivin蛋白的表达变化及其与放疗敏感性的关系。方法:采用免疫组织化学SP法检测56例食管鳞状细胞癌放疗前胃镜活检标本及放疗后食管癌根治性切除术后标本Fas和Survivin蛋白的表达水平,分析二者放疗前后表达的差异及其与放疗后病理反应分级的关系。结果:放疗前胃镜活检标本中Fas蛋白表达为0.47±0.23,放疗后食管癌根治性切除术后标本中Fas蛋白表达为0.61±0.17,放疗前后阳性率相比较差异有统计学意义(p<0.01);放疗前胃镜活检标本中Survivin蛋白表达为0.43±0.23,放疗后食管癌根治性切除术后标本中Survivin蛋白表达为0.37±0.40,放疗前后阳性率比较差异不具有统计学意义(P=0.49)。放疗前Fas蛋白表达与放疗后病理反应呈正相关,并有统计学意义(P<0.01),放疗后Fas蛋白表达与放疗后病理反应的相关性无统计学意义(P>0.05),放疗前后标本中Survivin蛋白表达与放疗后病理反应的相关性均无统计学意义(P>0.05)。结论:放疗前Fas蛋白表达与放疗后病理反应呈正相关,提示术前Fas蛋白表达可以代表肿瘤细胞的放射敏感性,Fas蛋白不但可以直接诱导肿瘤细胞的凋亡,而且可以预测肿瘤细胞的放射敏感性,Fas蛋白可作为中晚期食管鳞状细胞癌术前放疗的筛选指标之一。

Objective： To investigate the correlations between radiosensitivity and pre- and post-radiotherapy expression of Fas and Survivin in esophageal squamous cell carcinoma before surgery. Methods： Fifty-six patients with esophageal squamous cell carcinoma were enrolled. All of the patients were diagnosed by pathological examination and the samples excluded lymph node metastases. The pre-radiotherapy biopsy tumor samples were obtained via gastroscopy and the post-radiotherapy, post-surgery tumor samples were taken via esophagectomy performed to remove the esophageal squamous carcinoma tumors. Partial esophageal resection was performed with anastomosis of the esophagus, stomach and neck. The protein expression levels of Fas and Survivin were detected by SP immunohistochemistry. Statistical analysis was performed to investigate the correlations between pre- and post-radiotherapy expression levels of Fas and Survivin and the patho- logic response levels after radiotherapy. Results： Before radiotherapy, the expression levels of Fas were 0.47± 0.23. After radiotherapy and surgery, the expression levels of Fas were 0.61±0.17. Statistical analysis showed a significant increase in the positive rate of Fas expression （P〈0.01）. No significant difference was found in the positive rate of Survivin expression （P=0.49）. The expression levels of Survivin were 0.43±0.23 before radiotherapy and 0.37±0.40 after radiotherapy and surgery. The pre-radiotherapy expression of Fas in biopsy samples was significantly and positively associated with pathologic tumor response after radiotherapy （P〈 0.01）. However, the post-radiotherapy expression levels of Fas were not significantly associated with pathologic tumor response after radiotherapy （P〉0.05）. No significant difference was found in Survivin expression before and after radiotherapy, and no correlation was found between Survivin expression and pathologic response after radiotherapy （P〉0.05）. Conclusion： There is a positive correlation between Fas expression before radiotherapy and pathologic response after radiotherapy in esophageal squamous cell carcinoma, suggesting that Fas protein level could be used as a marker for tumor cell radiosensitivity. The expression level of Fas before radiotherapy may serve as a screening index for preoperative radiotherapy for patients with ad- vanced esophageal squamous cell carcinoma.