肝癌肝移植患者外周血中AFP mRNA和MXR7 mRNA的表达及其与预后的关系

Expression of AFP and MXR7 mRNA in the peripheral blood and its relationship with prognosis of patients with hepatocellular carcinoma following liver transplantation

目的:探讨甲胎蛋白(浕-fetoprotein,AFP)mRNA和米托蒽醌抗性基因(Mitoxantrone-resistant7,MXR7)mRNA作为游离癌细胞(isolated tumor cells,ITC)的标志物在肝癌肝移植患者外周血中的表达情况及其与术后肿瘤复发和转移的关系。方法:以2002年4月至2003年12月期间的53例肝癌肝移植患者为对象,通过建立稳定可靠的实时荧光定量RT-PCR检测方法来定量检测肝癌患者外周血全细胞中AFP mRNA和MXR7mRNA在整个肝移植术围手术期的表达和动态变化情况,并与术后肝癌复发和转移进行相关分析。结果:将研究对象分为肝癌移植组(53例)、晚期肝癌组(8例)、良性肝病组(26例)、正常对照组(10例),检测发现在肝移植术前,晚期肝癌组的AFP mRNA和MXR7mRNA其表达率均达到100%,在肝癌移植组中表达率分别为57.7%和53.6%。2者均明显高于在良性肝病组(表达率为19.2%和0)和正常对照组(表达率均为0)(P<0.05)。同时在2者的阳性结果表达水平上,晚期肝癌组和肝癌组要明显高于良性肝病组和正常对照组(P<0.05),前2者阳性结果定量水平达到1×1012copies/g RNA,是后2者定量水平的100-200倍。围手术期AFP mRNA和MXR7mRNA的表达无论是表达率还是阳性结果表达水平,均以在术中的检测标本为最高,而术后1周为次之。术后出现2次以上的持续性的AFP mRNA和MXR7mRNA的表达往往提示肝癌的复发和转移,较之移植术后没表达或一过性升高的病例,其差异有统计学意义(P<0.05),而术前和术中单次的AFP mRNA和MXR7mRNA的表达与否则对术后肝癌复发和转移无明显影响(P>0.05)。结论:AFP mRNA和MXR7mRNA可以作为肝癌ITC细胞的标志物,具有较好的特异性。术后血全细胞检测出现2次以上的持续性的AFP mRNA和MXR7mRNA的表达可以有效预测肝癌肝移植术后肿瘤复发和转移。

AIM： To investigate the expression pattern of α-fetoprotein（AFP） mRNA and Mitoxantrone -re- sistant 7 （MXR7） mRNA as surrogate markers for isolated tumor cells （ITC） in the peripheral blood of patients with hepa-tocellular carcinoma （HCC） following liver transplantation, and to correlate with tumor recurrence and metastasis after patients with HCC received liver transplantation. METHODS： In this prospective study, 97 patients were divided into four groups ： HCC group （ n = 53）, advanced HCC group （ n = 8）, benign liver disease group （ n = 26） and healthy volunteers （ n = 10）. RNA was purified from the peripheral blood of 53 patients in HCC group before, during and after liver transplan-tation and from 44 control patients. Complementary DNA （cDNA） synthesis by the fluorescent quantitative reverse tran- scriptase and polymerase chain reaction （FQ RT -PCR） for AFP and MXR7 gene were conducted. RESULTS： Using FQ - PCR to detect the expression of AFP mRNA and MXR7 mRNA in the peripheral blood of patients with HCC, we found that two surrogate markers in ITC were detected in 57.7% and 53.6% of patients in HCC group. While in advanced HCC group, the positive radio was all 100%. Compared with HCC group and advanced HCC group, the positive radio of the three surrogate markers in ITC was lower in benign l^ler disease group and healthy volunteer group （ P 〈 0.01 ）. In the mean time, the mean levels of the three surrogate markers in ITC in HCC group and advanced HCC group were 100 - 200 folds higher than those in benign liver disease group and healthy volunteer group （ P 〈 0.01 ）. An evident relation between the consistent presence of postoperative AFP mRNA and MXR7 mRNA and the recurrence and metastasis after HCC pa- tients received liver transplantation was also observed. CONCLUSION： AFP mRNA and MXR7 mRNA could be used as surrogate markers for ITC in HCC patients. The consistent presence of postoperative AFP mRNA and MXR7 mRNA in ITC may have clinically relevant with the recurrence and metastasis after HCC patients receive liver transplantation.