CD133与直肠癌新辅助放疗敏感性关系的研究

目的探讨肿瘤干细胞标记物CD133与直肠癌新辅助放疗敏感性的关系。方法回顾性分析杭州市第三人民医院2008—2010年间接受新辅助短程放疗（5Gy／d，x5d）的32例直肠癌患者的临床资料，采用免疫组织化学染色的方法检测放疗前直肠癌活检标本CD133的表达强度．采用直肠癌消退分级标准评价新辅助放疗后手术切除直肠癌组织对放疗的敏感性．分析两者的关系。结果32例直肠癌组织都不同程度表达CD133，其中高表达者17例，低表达者15例。CD133的表达强度与直肠癌分化程度有关．分化越低的直肠癌组织其CD133的表达越高（P〈0．05）。CD133高表达直肠癌患者中，放疗敏感性1级2例，2级5例，3级10例；15例低表达患者中，放疗敏感性1级5例，2级7例，3级3例；CD133表达与放疗敏感性之间存在显著相关性（P=0．037）。进一步行多因素回归分析显示，CD133表达强度（P=0．027）和肿瘤分化程度（P=0．046）是影响直肠癌放疗敏感性的两个独立因素。结论CD133表达强度与直肠癌放疗敏感性存在一定的相关性。

Association of CD133 expression and sensitivity of rectal cancer to preoperative radiotherapy

Objective To determine the association of CD133 expression with the sensitivity to radiotherapy among rectal cancer patients. Methods The clinical data of 32 rectal cancer patients was retrospectively collected for patients who received a short-term preoperative radiotherapy （5 Gy/d,×5 d） from 2008 to 2010. Pretreatment tumor biopsies were immunostained for CD133 expression. Rectal cancer regression grade （RCRG） was used to evaluate the sensitivity of the rectal cancer to preoperative radiotherapy. The correlation of CD133 expression and sensitivity to radiotherapy was analyzed. Results CD133 differentially expressed in rectal cancer tissue with 17 high expression and 15 low expression. The expression of CDI33 was associated with the differentiation of rectal cancer with higher expression of CD133 among poorly differentiated rectal cancers （P〈0.05）. Among the CD133-high patients, two patients showed 1st RCRG, five patients showed 2rid RCRG and ten patients showed 3rd RCRG. For the CD133-1ow patients, there were five 1st RCRG, seven 2nd RCRG and three 3rd RCRG. There was a significant association between CD133 expression and sensitivity to radiotherapy （P=0.037）. Multivariate logistic regression analysis showed that the expression level of CD133 （P=0.027） and the differentiation of rectal cancer （P=0.046） were independent predictive factors for the sensitivity of rectal cancer to radiotherapy. Conclusions Correlation between CD133 expression and sensitivity to radiotherapy of rectal cancer may exist, which may be helpful in predicting the sensitivity of rectal cancer to preoperative radiotherapy.