消化道肿瘤淋巴结转移灶多药耐药性的变化及其意义

The changes of mnltidrug resistance in metastatic lymph nodes of gastrointestinal tnmors

目的探讨消化道肿瘤淋巴结转移灶多药耐药性(MDR)的变化。方法对55例胃癌、大肠癌原发灶及相应淋巴结转移灶分别进行MDR相关蛋白(MRP)、P-糖蛋白(gp)、DNA拓扑异物酶(Topo)Ⅱα、谷胱甘肽S转移酶(GST)-л免疫组织化学染色,比较二病灶间诸指标表达程度的差异。结果原发灶与淋巴结转移灶比较:(1)两者的MRP、P-gp、TopoⅡα、GST-л表达一致率分别为32．7％、40．0％、45．5％、50．9％;(2)P-gp、GST-л阳性表达差异均有统计学意义(P<0．01); (3)中高分化腺癌的MRP、TopoⅡα阳性表达差异均有统计学意义(P<0．01,P<0．05),低分化腺癌仅GST-л阳性表达差异有统计学意义(P<0．01)。中高分化腺癌与低分化腺癌比较:原发灶中TopoⅡα阳性表达、转移灶中MRP及TopoⅡα阳性表达差异均有统计学意义(P<0．05)。结论消化道肿瘤淋巴结转移灶存在MDR的异质性变化,肿瘤原发灶的耐药基因相关蛋白表达水平不能预测淋巴结转移灶的MDR。

Objective To investigate the difference of multidrug resistance （MDR） between gastrointestinal primary tumors （PTs） and metastatic lymph nodes （MLNs）. Methods The S-P immunohistochemical technique was used to detect multidrug resistance-associated protein （MRP）, P-glycoprotein （P-gp） ,topoisomerase Ⅱα（TopoⅡα） and glutathione S transferase （GST-n） expression in PTs and MLNs from 48 cases of gastrointestinal tumors with metastatsis of lymph nodes. Results There was statistical difference in P-gp or GST-n expression （P 〈 0.01） between PTs and MLNs. Significant difference in MRP or Topo I] a expression was found in well differentated adenocarcinomas between PTs and MLNs （P 〈 0.01, P 〈 0.05）, and GST-n expression in poorly differentated adenocarcinomas （P〈0.01 ）. As compared between well and poorly differentated adenocarcinomas, the difference in the Topo Ⅱα expression level in PTs was statistically significant （ P 〈 0.05 ）, and difference in MRP or TopoⅡα level expression also was significant in MLNs （ P 〈 0.05）. Conclusion There was significant heterogeneity of MDR in metastatic lymph nodes as compared with gastrointestinal primary tumors. Resistance-associated proteins as MRP, P-gp,TopoⅡα, GST-n expression levels in PTs cannot be used to predict MDR of MLNs.