GSTPi在正常胰腺、慢性胰腺炎与胰腺癌中的表达及临床意义

Expression of GSTPi in Normal Pancreas, Chronic Pancreatitis and Malignant Pancreas:an Immunohistochemical Study

GSTPi在多种恶性肿瘤中有较高表达,有人认为它是诊断癌肿的标志物,此外,它与癌肿对化疗耐药性有关,我们用免疫组化法检测36例胰腺导管癌,15例胰腺癌转移淋巴结,10例慢性胰腺炎和12例正常胰腺的GSTPi表达,结果表明:包括正常胰腺和慢性胰腺炎的非肿瘤组与肿瘤组的GSTPi单抗阳性染色率无明显差异(P>0.5);原发胰腺癌GSTPi阳性率显著高于相应淋巴结转移灶(P<0.01);经Kaplan-Meier曲线比较和log-rank检验结果显示:GSTPi染色阴性组胰腺癌预后优于阳性组,提示:GSTPi不能作为病理诊断胰腺癌的标志物,原发胰腺癌与相应淋巴结转移灶对化疗敏感性存在差异,GSTPi可作为判断胰腺癌术后预后参数之一。

GSTPi is expressed by miscellaneous human malignancies at high level. Overexpresssion of GSTPi in malignant tissue combined with its expression in preneoplastic and neoplastic lesions has been used to argue that GSTPi is a 'tumor diagnostic marker', but this has not been widely accepted yet. Moreover, GSTPi has been found to relate to tumor drug resistance. In this study, 36 pancreatic adenocarcinomas, 15 lymph node metastatic samples from the above malignancies, 10 chronic pancreatitis and 12 normal pancreatic samples were examined immunohistochemically for expression of GSTPi. No significant difference of GSTPi expression has been found between non - tumor samples (including normal pancreas and chronic pancretitis) and malignant samples (P>0.5). GSTPi is expressed by primary pancreatic cancers at markedly higher level than corresponding metastatic lesions in lymph nodes (F<0.001). Compared by Kaplan -Meire's curve and Log-rank test, pancreatic adenocarcinomas with negative GSTPi staining have a better prognosis than positive ones. Thus, we conclude that expression of GSTPi cannot be used as a tumor diagnostic marker. Discrepancy of sensitivity to chemotherapy may exist between primary and metastatic lesions of pancreatic cancers. Expression of GSTPi in pancreatic cancers can be used as a marker of prognosis.