大肠肿瘤癌基因蛋白产物同步检测的对比分析

A STUDY OF EXPRESSION OF ONCOGENE PROTEIN PRODUCTS IN COLORECTAL TUMORS

对大肠肿瘤连续切片组织同步进行了Ｃ－ｍｙｃ．Ｐａｎ－ｒａｓ和Ｐ５３三种癌基因蛋白产物的检测，结果显示：癌基因ｍｙｃ、ｒａｓ和Ｐ５３阳性表达率在结肠腺瘤分别为６１．１％（４４／７２）、３７．５％（２７／７２）和５．６％（４／７２），大肠腺癌分别为７２．９％（５１／７０）、５１．４％（３６／７０）和４０．０％（２８／７０），而正常粘膜则分别为２８．０％（７／２５）、４．０的（１／２５）和０。印戒细胞癌仅有１例呈ｒａｓ蛋白表达阳性（１６．７％），对比三种癌基因产物检测结果，有二种以上癌基因蛋白产物同时表达呈阳性者在腺瘤有１４例（１９．４％），腺癌３７例（５２．９％）。腺瘤中主要为ｍｙｃ＋ｒａｓ同时表达阳性（１３．９％）。腺癌中ｍｙｃ＋ｒａｓ、ｍｙｃ＋Ｐ５３、ｒａｓ＋Ｐ５３、ｍｙｃ＋ｒａｓ＋Ｐ５３同时表达者分别为２４．３％、７．１％、５．７％、１５．７％。进一步分析表明，腺瘤病变中癌基因表达与不典型增生程度有关，其中同时呈二种以上表达者在轻度不典型增生仅为８．３％（４／４８）、中度为３３．３％（５／１５）和重度５５．６％（７／９）。而大肠癌蛋白产物表达阳性率与癌分化程度无明确关系。

he expression of protein products of oncogene C-myc,Pan-ras and P53 were studied by meansof immunohistochemical method in serial tissue sections of 25 cases of normal colon mucosa,72adenomas (48 with mild dysplasia,15 with moderate dysplasia and 9 with severe dysplasia),70adenocarcinomas and 6 signet-ring cell cancers.The results showed that the positive ratea of myc,ras and P53 expression were 61.1%, 37.5%and 5.6%respectively in adenomas and 72.9%, 51.4%and 40.0% in adenocarcinomas,while those in normal controls were only 28.0%,4.0%and 0%.Noexpression of oncogene was observed in signet-ring cell cancers except one case with ras positive.Expressions of two or three oncogenes occurred in l9.4% of adenomas and 52.9% ofadenocarcinomas.In adenomas,myc+ras,was responsible for main co-expression(13.9%), whereasin adenocarcinomas, co-expression of myc+ras,myc+P53, ras+P53 and myc+ras+P53 were24.3%,7.1%,5.7%and l5.7% respectively.Further study showed that the positive rates ofoncogene expressions in adenoma were related to the severity of dysplasia,being 8.3%, 33.3%and55.6% respectively in mild,moderate and severe dysplasia.Howerver,this relation was notobserved in adenocarcinomas in various degrees of differentiation.