增殖细胞核抗原(PCNA)在大肠腺瘤—癌序列中的表达及其价值

Proliferating cell nuclear antigen (PCNA) expression and its significance in adenoma-carcinoma sequence of the large bowel.

采用ABC-PAP免疫组化法,用增殖细胞核抗原(PCNA)单抗PC_(10),对大肠腹瘤—癌序列的细胞动力学改变进行了研究。活检或切除的11例正常粘膜,52例腺瘤及20例腺癌被纳入本研究。计数1000个细胞中阳性细胞数作为PCNA计数值。结果显示:正常结肠粘膜PCNA阳性细胞局限在腺体下2/3区域;而腺瘤则可见于腺体上1/3;在腺癌,阳性细胞弥漫分布于整个腺管,甚至上皮表面,PCNA计数值在腺瘤和腺癌较正常明显增高(P<0.01)。在腺瘤中随异型增生程度加重,其计数值逐渐增高(P<0.05)。在重度异型增生和腺癌间其计数值比较差异无显著性(P>0.05).PCNA计数值与腺瘤的大小和组织学类型无关(P>0.05)。结果提示:PCNA免疫组化染色对识别腺瘤的恶性潜能及早期癌变有重要参考价值,对区别腺瘤异型增生程度也有一定价值。

The cell kinetics of the adenoma-carcinoma sequence of large bowel were investigated using ABC-PAP immunohistochemicai technique with monoclonal antibody PC10. Biopsy or sectioned specimens of normal mucosa (n=1l), adenoma with dysplasia (n=52) and adenocarcinoma (n=20) of the large bowel were used for this purpose. PCNA count was determined by calculating the positive cells per 1000 cells. The results showed that the PCNA positive cells were confined to the lower two-thirds of normal mucosal crypts, whereas positive cells were found at the upper parts of the glands in adenomas. In adenocarcinomas the positive cells spread diffusely along the glands, even arrived at the surface epithelium. The adenomas and adenocarcinomas showed increased PCNA count as compared with those of normal mucosa (P<0.01). There was increased PCNA count in adenomas with increasing degree of dysplasia (P<0.05). There was no statistical difference between the PCNA count in adenomas with severe dysplasia and that in adenocarcinomas (P>0.05). No significant correlation was observed between PCNA count and histologic type and size of adenomas (P>0.05). It's concluded that PCNA immunohistochemicai staining is valuable in early detection of malignant potential of adenomas, also it may be helpful in distinguishing the degree of adenomatous dysplasia.