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

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

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.

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.