鼻咽癌组织放疗前后细胞增殖凋亡的变化

目的 研究鼻咽癌组织放疗前后细胞增殖凋亡的变化。方法 采用TdT酶介导的生物素化dutp制品末端标记技术（terminal oxynucleotidyl transferase mediated dUTP biotion mick end labeling,TUNEL）和免疫组化S－P法，分别检测60例鼻咽癌患者在放疗前、放疗第2周、第4周时细胞凋亡率（apoptosis rate,AR）和增殖细胞核抗原（proliferation cell nuclear antigen,PCNA）的表达。结果 鼻咽癌组织放疗后的AR明显高于放疗前；常规分割放疗组放疗第4周后的AR较放疗第2周时下降，而PCNA增殖指数升高（P＜0．01；加速超分割放疗组放疗第2周和放疗第4周的AR、PCNA增殖指数均无显著差异（P＞0．05）。结论 放射治疗鼻咽癌可以加速癌细胞的凋亡，鼻咽癌自发性细胞凋亡与放疗诱发的凋亡呈正相关。常规分割放疗过程中存在肿瘤细胞加速再增殖和细胞凋亡率下降，而采用超分割放疗可以减少鼻咽癌细胞加速再增殖，提高凋亡率。

APOPTOSIS AND CELL PROLIFERATION OF NASOPHARYNGEAL CARCINOMA BEFORE AND AFTER RADIOTHERAPY

Objective To study the effect of radiotherapy on the apoptosis and cell proliferation in nasopharyngeal carcinoma(NPC). Methods 60 cases of NPC was divided into 2 groups:conventional radiotherapy group and hyperfractionation group. Paraffin embeded tissue blocks obtained before radiotherapy and from the 2 nd and 4 th weeks during radiotherapy were used in this study. Using terminal oxynucleotidyl transferase mediated dUTP biotin nick end labeling (TUNEL) and immunohistochemical S P staining, the apoptosis rate (AR) and the expression of proliferation cell nuclear antigen (PCNA) were examined. Results The AR of radiation induced apoptosis was significantly higher than that before radiotherapy. The AR of the second week during conventional radiotherapy was higher than that of the fourth week, while the expression of PCNA was lower than that of the fourth week ( P <0.01); but there was no difference between the second and the fourth week during hyperfractionation radiotherapy( P >0 05).Conclusion The process of aopotosis is accelerated by radiotherapy in NPC. The decrease of apoptosis and the increase of cell proliferation in nasopharyngeal carcinoma during conventional radiotherapy is obvious and hyperfractionation radiotherapy can increase AR and decrease proliferation.$$$$