p27和p53基因在大肠癌中的表达及临床意义

EXPRESSIONS OF GENES p27 AND p53 IN COLORECTAL CARCINOMA AND THEIR CLINICAL SIGNIFICANCE

目的研究大肠癌患者癌组织中p27、p53基因的表达及其相互之间的关系,以探讨p27、p53基因在大肠癌发生中的作用及临床意义。方法运用原位杂交方法及免疫组化SP法检测58例大肠癌组织及正常黏膜中p27mRNA和P27蛋白的表达,同时运用免疫组化法分析相同组织中P53蛋白表达状况。结果p27mRNA在大肠癌组织及正常黏膜中的表达阳性率均为100%。P27蛋白在大肠癌组织中的表达阳性率为55.17%,在正常黏膜中的表达阳性率为96.55%(P<0.01);癌组织中P53蛋白表达阳性率为53.45%,正常黏膜未见P53蛋白表达(P<0.01);大肠癌组织中P27与P53蛋白表达无明显相关性。P27蛋白的表达与肿瘤分化程度呈负相关(P<0.01),与临床其它病理因素均无相关性(P>0.05)。大肠癌组织中P53蛋白表达与临床病理因素亦无相关性(P>0.05)。结论P27蛋白表达的调控主要在转录后水平,P27蛋白检测可作为评价大肠癌恶性程度和预后判断的重要指标。P27及P53蛋白在大肠癌的发生发展过程中具有重要作用。

Objective To study the expression and clinical significance of p27 and p53 genes in colorectal carcinoma. Methods In situ hybridization for p27 mRNA was performed in 58 cases of colorectal carcinoma and normal mucosa. The expression of P27 and P53 proteins was detected by immunohistochemical staining （S-P method） in the same cases. Results The positive rates of p27 mRNA expression in colorectal carcinoma and normal colorectal mucosa were 100%. The positive rates of P27 protein were 55.17% in colorectal carcinoma and 96. 55% in normal mucosa （P〈0.01）. 53.45% of cancer tissues expressed P53 protein, but no p53 protein expression was detected in normal mucosa. No relationship was found between P27 and P53 protein expressions. The expression of P27 protein was inversely correlated with the histological grade （P〈0. 01）, but not correlated with the other clincopathological factors. The protein expression of p53 gene was not correlated with clincopathological factors. Conclusion P27 protein expression is regulated mainly at posttranscriptional level. Detection of P27 protein could be useful in evaluating the malignant degree and prognosis of colorectal carcinoma. Alterations of P27 and P53 proteins play important roles in the carcinogenesis of colorectal carcinoma.