定量PCR法检测胃癌多药耐药基因的表达

Quantitative analysis of Mdr_1 expression by PCR in patients with gastric carcinoma

肿瘤细胞对化疗药物的耐药性是癌症化疗中的主要难题。人类多药耐药基因Ｍｄｒ１的过度表达是耐药的主要原因。我们利用逆转录ＰＣＲ技术（ＲＴ－ＰＣＲ）定量分析１３例老年及老年前期胃癌患者Ｍｄｒ１表达水平，探讨其与临床化疗之间的相关性。对胃癌组织标本的初步检测表明，胃癌化疗疗效与Ｍｄｒ１表达水平的高低有关。初次发现未经化疗的胃癌患者，Ｍｄｒ１呈低表达（＜０．３０）；化疗反应好的缓解期患者Ｍｄｒ１亦呈低表达（＜０．３０），但随着缓解期的延长、疗程的增加，Ｍｄｒ１表达有增高趋势（０．３０～０．４０）；经化疗未缓解而发生转移或复发的患者Ｍｄｒ１呈高表达（＞０．４０）。

Abstract The resistance of tumor cells to drugs is a major obstacle to effective cancer chemotherapy. The major mechanism of drug resistance is associated with over expression of human multidrug resistance gene(Mdr1).This gene encodes a transmenbrane P-glycoprotein, which acts as an effiux pump and results in decreased intracellular drug accumulation. The levels of Mdr1 mRNA in tissue samples of 13 senile and presenile patients with gastric carcinoma were quantitatively ineasured by RT-PCR method. Our results showed that the levels of Mdr1 expression are correlated with the response of patients to chemotherapy. In newly found cases before chemotherapy Mdr1 expression was low(<0.30) . In patients with good response during remission Mdr1 expression was also low, but with the prolongation of remission and increased courses of chemotherapy;Mdr1 expression tended to rise(0.3-0.4). In patients with no response to chemotherapy and showed metastasis or relapse Mdr1 expressions were high(>0.4).