放大色素结肠镜观察FAS、Ki-67在直肠异常隐窝病灶中的表达

目的:观察FAS、Ki-67在结肠腺瘤、异常隐窝病灶(aberrant crypt foci,ACF)中的表达,探讨脂肪酸合成酶(fatty acid synthase,FAS)、增殖细胞核抗原(Ki-67)的异常表达在结直肠癌癌前病变形成中的意义.方法:对34例结肠镜确诊为腺瘤性息肉患者,常规内镜检查结束时,用0.2%的亚甲蓝溶液染色直肠黏膜,然后使用放大结肠镜观察直肠寻找ACF.对结肠腺瘤性息肉、ACF及正常黏膜活检标本进行免疫组织化学分析其FAS和Ki-67的表达.结果:34例结肠腺瘤性息肉患者,其中31例直肠发现ACF,共发现并活检ACF166处(其中伴异型增生14处,不伴异型增生152处).FAS、K i-67在结肠腺瘤、A C F中呈异常高表达(P<0.01).伴异型增生ACF中FAS、Ki-67表达较不伴异型增生ACF无明显上调.结论:FAS、Ki-67在结直肠癌的癌前病变(腺瘤、ACF)呈异常高表达.结直肠癌的癌前病变存在细胞能量代谢异常及异常增殖,在ACF阶段就已经异常增殖明显,抑制FAS有望成为结直肠癌预防、治疗的靶点.

Overexpression of FAS and Ki-67 in aberrant crypt foci from patients with adenoma

AIM:To detect the expression of fatty acid synthase(FAS) and Ki-67 in colonic adenoma and aberrant crypt foci to explore their significance in the formation of precancerous lesions.METHODS:Aberrant crypt foci(ACF) in the rectum of 34 patients with adenoma were identified by magnification chromoendoscopy(MCE) after staining with 0.2% methylene blue solution.Specimens with ACF were biopsied to detect the expression of FAS and Ki-67 by immunohistochemistry.RESULTS:A total of 166 ACF were found in 31 patients,of which 14 had atypical hyperplasia and 152 had no atypical hyperplasia.The expression of FAS and Ki-67 in colonic adenoma and ACF were significantly higher than that in normal tissue(all P < 0.01).There was no significantdifference in the expression of FAS and Ki-67 between ACF with and without dysplasia.CONCLUSION:The expression of FAS and Ki-67 is higher in colorectal precancerous lesions.FAS may be used as a target for preventing and treating colorectal cancer.