肾上腺皮质肿瘤Ki67表达和P16蛋白表达的相关性及意义

目的研究肿瘤增殖抗原Ki67和抑癌基因P16与肾上腺皮质肿瘤的关系。方法应用免疫组化方法检测68例肾上腺皮质肿瘤（腺瘤60例、腺癌8例）及9例瘤旁正常组织标本中Ki67及P16的标记指数（La—beling Index，LI）。结果Ki67在正常肾上腺组织不表达，在腺癌表达最高，腺瘤次之；P16在正常肾上腺组织表达最高，腺瘤次之，腺癌最低，Ki67和P16在肾上腺皮质肿瘤表达的结果相比较差异有显著性（P〈0．001），且存在负相关关系（r=-0．7136，P〈0．05）。Ki67的LI在肾上腺皮质腺瘤、腺癌的界定值（cut point）为4％；P16的LI在肾上腺皮质腺瘤、腺癌的界定值为12％。结论Ki67及P16的表达与肾上腺皮质肿瘤显著相关，肾上腺皮质肿瘤组织Ki67的LI〉4％和P16的LI〈12％时，提示为腺癌。联合检测Ki67和P16在肾上腺皮质肿瘤的表达对区别良、恶性肾上腺皮质肿瘤具有重要意义，可以作为早期诊断肾上腺皮质腺癌的生物学指标之一。

Expression and significance of Ki67 and P16 in adrenocortical tumors tissue

[Objective] To study the relationship between Ki67, P16 and adrenocortical tumors. [Methods] The Labeling Index (LI) of Ki67 and P16 was detected by immunohistochemical staining in 68 cases of adrenocortical carcinoma(8 cases), adrenocortical adenoma (60 cases) and normal adrenocortical tissue beside tumor (9 cases). [Results] There is the highest expression of Ki67 and the lowest expression of P16 in adrenocortical carcinoma. There exist negative correlation between the expression of Ki67 and P16 (r=-0.7136,P <0.05). There is significant difference in the LI of Ki67 and that of P16 between adrenocortical carcinoma and adrenocortical adenoma (P <0.001 ). The cutpoint of LI of Ki67 was 4% and the cutpoint of LI of P16 was 12% in adrenocortical carcinoma. [Conclusions] The LI of Ki67 above 4% and LI of P16 below 12%,is a sensitive indicator of adrenocortical carcinoma. It is suggested that combine detecting the expression of Ki67 and P16 may be taken as one of biomarkers for differentiation of adrencortical adenomas from adrencortical carcinomas.