卵巢癌组织中二氢叶酸还原酶基因的表达及其临床意义

摘要

目的 探讨卵巢癌组织中二氢叶酸还原酶基因(dinhydrofolate reductase,DHFR)的表达及其临床意义.方法 采用实时荧光定量PCR法检测80例卵巢癌组织、50例良性卵巢组织及30例正常卵巢组织中的DHFR mRNA表达情况,分析其与卵巢癌临床病理及多药耐药的相关性.结果 1)DHFR mRNA在正常卵巢组织、良性卵巢肿瘤和卵巢癌组织中表达量分别为0.584±0.234、0.895±0.783和0.197±0.412,经比较差异有统计学意义(P<0.001,P=0.027,P<0.001).2)卵巢癌组织中DHFR mRNA表达量与患者临床分期及病理分级差异无统计学意义(P>0.05),但在上皮性癌中浆液性癌组织中DHFR mRNA表达量则明显高于黏液性和内膜样癌,经比较差异有统计学意义(P<0.001).3)卵巢癌组织中DHFR mRNA表达量与患者的腹水量、淋巴结转移和远处器官转移无明显相关(P>0.05),但大网膜转移者肿瘤组织中DHFR mRNA表达量则低于无转移者(P=0.044).4)在卵巢癌患者中治疗后缓解者组织中DHFR mRNA表达量低于肿瘤进展者(P<0.001);而铂类药物敏感型患者肿瘤组织中DHFR mRNA表达量0.130±0.103也低于铂类药物耐药者0.341±0.701(P=0.011).5)DHFR mRNA表达量判断卵巢肿瘤性质的ROC曲线Youden指数最大值所对应的数值为0.331,DHFR mRNA表达量>0.331的患者中位生存时间为16.4个月,而≤0.331的患者中位生存时间为44.5个月,差异有统计学意义(P<0.001),且Cox模型多因素分析亦显示DHFR mRNA表达量为影响预后的独立因素(P=0.018).结论 DHFR mRNA在正常和良性卵巢组织中表达量高于卵巢癌组织,提示DHFR参与正常组织细胞生理代谢,而在卵巢癌中DHFR mRNA在铂类耐药组织中表达较高,在铂类敏感组织表达低,提示DHFR与卵巢癌多药耐药相关,可能为判断卵巢癌多药耐药潜在标志之一.%Objective: The current study aims to investigate the dihydrofolate reductase ( DHFR ) mRNA expression in ovarian cancer as well as elucidate the relationship between the clinical pathologic parameters and the DHFR mRNA expression in ovarian cancer. Method: DHFR expression was detected in 80 cases of ovarian carcinoma, 50 benign ovarian cases and 30 normal controls by real-time fluorescent quantitative polymerase chain reaction. Results: The DHFR mRNA expression in ovarian carcinoma, benign ovarian tumor, and normal ovarian tissues was 0.584±0.234, 0.895±0.783, and 0.197±0.412, respectively, with statistically significant differences ( P < 0.000, P = 0.027, P O.001 ). No relationship was found between the DHFR mRNA expression and stage or pathological grade of ovarian cancer. But DHFR mRNA expression in serous carcinoma was significantly higher than that in mucinous and endometrioid carcinoma ( P = 0.000 ). DHFR mRNA expression in ovarian cancer was not related with the amount of ascites, lymph node metastasis, or distant metastasis (P > 0.05 ), but the DHFR mRNA expression in patients with omentum metastasis was lower than that in patients without omentum metastasis, with a statistically significant difference ( P = 0.044 ). DHFR mRNA expression in patients with CR for treatment was lower than that of patients with SD or PD or PR ( P < 0.001 ). The expression of DHFR mRNA in cisplatin-sensitive patients was lower than that in cisplatin-multidrug resistant cases [ ( 0.130 ± 0.103 ) vs. ( 0.341 ± 0.701 ), P = 0.011]. The Youden index of the ROC curve for DHFR mRNA expression was 0.331. The median survival period of patients with DHFR mRNA expression lower than 0.331 was 16.4 months, but the median survival time of patients with DHFR mRNA expression higher than 0.331 was 44.5 months, with a statistically significant difference ( P < 0.001 ). COX multivariate analysis showed that DHFR mRNA expression was a dependent prognostic factor ( P = 0.018 ). Conclusion: DHFR plays a role in physiological metabolism in normal cells. A relationship exists between upregulated DHFR mRNA expression and cisplatin-multidrugresistance in ovarian cancer. DHFR mRNA expression could be used as a marker to determine cisplatin-multidrug resistance in ovarian cancer.