p53,p21表达与直肠癌放疗敏感性的关系

Relationship between p53, p21 expression and radiosensitivity in rectal carcinoma

目的 :寻找直肠癌放疗敏感性与抑癌基因 p5 3和 p2 1的关系。方法 :应用 ABC免疫组织化学方法检测 6 5例直肠癌患者放疗前肿瘤组织 p5 3和 p2 1的表达 ,并与放疗后肿瘤组织病理学变化进行比较。其中男性 44例 ,女性 2 1例 ,平均年龄5 4.3岁。在 6 5例肿瘤中 ,高分化腺癌 34例 ,中分化腺癌 18例 ,粘液腺癌 6例 ,低分化腺癌 7例。依据术后切除标本分类 ,Dukes A5例 ,Dukes B38例 ,Dukes C17例 ,Dukes D5例。每例放疗总剂量为 5 0 Gy。 结果 :p5 3与 p2 1出现反向表达结果。组织病理学检测 ,6 6 .7%的 p5 3(- )和 75 .0 %的 p2 1(+ )肿瘤对放疗敏感 ,而 88.6 %的 p5 3(+ )和 80 .0 %的 p2 1(- )肿瘤对放疗不敏感 ;p5 3(+ )或 p2 1(- )表达与肿瘤分化和临床分期无关。结论 :免疫组化 p5 3和 p2

Objective:To study the relationship between p53, p21 expression and radiosensitivity in rectal carcinoma. Methods: p53 and p21 expression in formalin fixed, paraffin embedded, preradiation biopsy samples from 65 patients with rectal carcinoma were analyzed immunohistochemically and their relationship with tumor radiosensitivity were evaluated. Results: p53 and p21 expression were 54.3% and 29.8% respectively. Significant histopathological effect was observed in 35.5% of the tumors. There was a significant inverse expression between p53 and p21. Most of the p53(+) and/or p21(-) tumors were radioresistant while the majority of p53(-) and/or p21(+) were radiosensitive. Radiosensitive tumor decreased more significantly (47.4%) in size than radioresistant ones (22.4%). Conclusion: p53 and p21 may play important role in determing tumor radiosensitivity in rectal carcinomas.