【摘要】 目的 探讨凋亡抑制蛋白Livin与凋亡蛋白Caspase-3在结直肠腺瘤-癌序列中的表达变化及其相关性。 方法 2006年7月—2009年12月，采用免疫组织化学染色链霉菌抗生物素蛋白-过氧化物酶链接法streptavidin-peroxidese，SP）法检测18例正常黏膜、84例结直肠腺瘤、72例结直肠癌中Livin及Caspase-3的表达情况。 结果 结直肠腺瘤组织中Livin蛋白的阳性表达率明显高于正常黏膜组织（Plt;0.05），而低于腺癌组（Plt;0.05）；腺瘤组内绒毛状腺瘤与管状腺瘤相比较，Livin蛋白表达率差异有统计学意义（Plt;0.05）。结直肠腺瘤组织中Caspase-3的阳性表达率明显高于正常黏膜组织（Plt;0.05）；而腺瘤组织与癌组织之间Caspase-3阳性表达率差异（Plt;0.05）；腺瘤组内绒毛状腺瘤与管状腺瘤相比较，Caspase-3蛋白阳性表达率差异无统计学意义（Pgt;0.05）。Livin表达与Caspase-3表达呈负相关（Plt;0.05）。 结论 凋亡抑制蛋白Livin参与了大肠肿瘤的发生，且在大肠腺瘤-腺癌阶段起到了重要作用；凋亡抑制蛋白Livin与Caspase-3表达呈负相关，抑制Caspase-3蛋白的活性可能是Livin促进结肠癌发生的途径之一。【Abstract】 Objective To investigate the expression of Livin and Caspase-3 among colorectal adenoma-carcinoma sequence, and to identify the relationship between Livin and Caspase-3 expression in colorectal adenoma-carcinoma sequence. Methods Formalin-fixed paraffin embedded colorectal tissues from 174 patients, including 84 adenomas, 72 carcinomas, and 18 normal mucosa, were examined for expression of Livin and Caspase-3 by streptavidin-peroxidase (SP) immunohistochemistry between July 2006 and December 2009. Results The positive rates of Livin protein expression in colorectal adenoma was significantly higher than that in normal mucosa (Plt;0.05), but lower than that in adenocarcinoma (Plt;0.05); the expression of Livin in tubular adenoma was significantly higher than that in villous adenoma (Plt;0.05). The positive rates of Caspase-3 protein expression in colorectal adenoma were significantly higher than that in normal mucosa and carcinoma (Plt;0.05), and the difference in positive rate of Caspase-3 expression was not significant between the villous adenoma and tubular adenoma (Pgt;0.05). Livin expression had negative correlation with the Caspase-3 expression (Pgt;0.05). Conclusion The difference in expression of Livin between adenoma and adenocarcinoma indicates the potential value of it in carcinogenesis of colorectal cancer, which suggestes that suppressing Caspase-3 protein activity is one of the channels by which livin promotes colorectal carcinogenesis.