水甘油通道蛋白7与原发性肝细胞癌的相关性研究

Expression of aquaglyceroporin 7 in human hepatocellular carcinoma

摘要:

目的：检测水甘油通道蛋白7（aquaglyceroporin，AQP7）是否在肝组织中有表达，并观察其在原发性肝细胞癌（human hepatocellular carcinoma，HCC）组织及其配对癌旁肝脏（non-tumourigenic liver，NTL）组织，以及正常肝脏（normal liver，NL）组织中的表达差异，并结合临床病理探讨AQP7与HCC发生发展的相关性。方法：收集34例HCC患者的HCC组织及其配对NTL组织和4例NL组织，分别应用real-time PCR法、蛋白免疫印迹（Western blot）法、免疫组织化学技术，在基因与蛋白、定性及定位层面检测HCC及NTL、NL组织中AQP7的表达情况。收集临床病理资料，分析AQP7的差异表达与患者临床病理参数的相关性。结果：（1）AQP7在所有HCC及NTL、NL组织中均有表达，免疫组化结果显示其主要表达于肝细胞胞膜及胞浆。（2）在HCC组织中AQP7的表达量无论在基因还是蛋白水平明显低于NTL与NL组织，NTL与NL组织中AQP7的表达量无明显差异：mRNA水平，NL组表达量与NTL组相比，无统计学差异（P=0.072），HCC组表达量明显低于NTL组（t=3.841，P=0.000）及NL组（P=0.001）；蛋白水平，NL组与NTL组无明显统计学差异（t=0.264，P=0.798），HCC组表达量明显低于NTL组（t=7.333，P=0.000）及NL组（t=5.648，P=0.011）。（3）应用多元线性回归分析法分析患者HCC组织中AQP7降低的差值与临床参数的相关性分析，发现有淋巴结转移的患者降低幅度更大（t=-2.837，P=0.008）。回归方程为：Y=1.612-0.472 X7（F=8.048，P=0.008）。结论：AQP7在人肝脏组织上有大量表达，主要表达于肝细胞胞膜及胞浆，且在ＨＣＣ组织上表达较其配对ＮＴＬ组织及ＮＬ组织表达明显降低，有淋巴结转移的患者降低幅度更大。

Abstract:

Objective：To determine whether human hepatocytes express aquaglyceroporin 7（AQP7），to detect the differential expression of AQP7 in human hepatocellular carcinoma（HCC） tissues，pair-matched non-tumourigenic liver（NTL） tissues and normal liver（NL） tissues，to investigate its correlation with the occurrence and progress of HCC. Methods：Fresh frozen HCC tissues and pair-matched NTL tissues were collected from 34 patients diagnosed with HCC，and NL tissues were collected from 4 patients with hepatic heman－gioma. AQP7 gene and protein expression of the three kinds of tissues was detected by real-time PCR，Western blot and immunohis－tochemical method. Then the correlation analysis between AQP7 expression and clinical features was done. Results：AQP7 was ex－pressed in hepatocytes，both intracellular and in membrane localized. Both levels of AQP7 mRNA and protein were significantly lower in HCC tissues than in NTL and NL tissues. No obvious difference in AQP7 mRNA and protein levels was found between NTL and NL tissues. AQP7 mRNA levels were not statistically different between NL group and NTL group（P=0.072）. AQP7 protein levels were not statistically different between NL group and NTL group（t=0.264，P=0.798）. AQP7 protein levels were lower in HCC group than in NTL group（t=7.333，P=0.000） and NL group（t=5.648，P=0.011）. Low expression of AQP7 in HCC was correlated with the lymphatic metastasis and the reduction of AQP7 was greater among the patients with lymphatic metastasis（t=-2.837，P=0.008）. Re－gression equation：Y=1.612-0.472 X7（F=8.048，P=0.008）. Conclusion：AQP7 is expressed in hepatocytes，both intracellular and in membrane localized. AQP7 decreases expression in HCC tissues. And the reduction of AQP7 is greater among the patients with lym－phatic metastasis.