中文摘要：

目的检测乙醛脱氢酶1（ALDH1）在结直肠癌中的表达,探讨其与结直肠癌临床病理特征的关系。方法收集西南医院2006-2010年送检的结直肠癌组织及正常结直肠组织标本各75例,取结直肠癌与正常结直肠组织标本各70份,采用免疫组织化学法检测其ALDH1的表达,采用Real time RT-PCR、Western blotting检测其余各5例结直肠癌及正常结直肠组织中ALDH1的表达情况。结果免疫组织化学染色表明,ALDH1主要表达于结直肠癌肿瘤细胞和正常结直肠黏膜上皮细胞的胞质内,且在正常结直肠组织的阳性表达率（83%）显著高于结直肠癌组织（37%,P=0.000）。ALDH1 mRNA在正常结直肠组织的表达水平是结直肠癌组织的1.4~17倍。Western blotting检测结果显示,ALDH1在正常结直肠组织中的表达是结直肠癌组织的1.02~3.99倍。统计分析显示,ALDH1的表达与结直肠癌患者的年龄、性别以及肿瘤部位、浸润深度、分化程度、淋巴结转移、Dukes＇分期等无相关性（P〉0.05）。结论 ALDH1在正常结直肠组织中的表达显著高于结直肠癌组织,其表达与结直肠癌患者的临床病理特征之间无显著相关性。

英文摘要：

Objective To observe the expression of aldehyde dehydrogenase 1（ALDH1） in colorectal carcinoma and explore its clinicopathological significance.Methods Samples were collected from 75 patients admitted to Southwest Hospital from Jan.2006 to Sep.2010.Each sample consisted of both colorectal carcinoma and normal colorectal tissue of the same individual.Immunohistochemistry SP was used to detect the expression of ALDH1 in 70 samples,and real time RT-PCR and Western-blotting were used to detect the expression of ALDH1 in the remaining 5 samples.Results Using immunohistochemistry SP,the ALDH1 was found to be expressed in cytoplasm of colorectal carcinomas and normal colorectal mucosal epithelium.The expression of ALDH1 was detected in a significantly greater proportion of normal colorectal tissue（83%） than that of colorectal carcinoma（37%）.ALDH1 mRNA levels in normal colorectal tissue was 1.4 to 17-fold higher than that in colorectal carcinoma tissue.Similarly,the expression level of ALDH1 protein in normal colorectal tissue was 1.02 to 3.99-fold higher compared with that in colorectal carcinoma tissue.However,by statistical analysis,the expression levels of ALDH1 in colorectal carcinoma was not correlated with the clinical pathological characteristics,such as age,gender,location,infiltration,pathological stage,metastasis,and Dukes＇ stages（P0.05）.Conclusions The expression of ALDH1 is stronger in normal colorectal tissue than in colorectal carcinoma.However,the expression of ALDH1 in colorectal carcinoma is not correlated with the characteristics of clinical pathology.