表皮型脂肪酸结合蛋白在跨种属肝癌组织中的表达

Expression of epidermal fatty acid-binding protein in cross-species hepatoceilular carcinoma

目的应用跨种属肿瘤关键基因筛选策略，从已报道的大量肝癌相关基因中筛选、定位出影响肝癌发生和发展的关键分子。方法结合本课题组的前期实验数据及国内外文献数据，建立肝癌差异表达分子的跨种属数据集，对首批筛选出的候选分子表皮型脂肪酸结合蛋白（E—FABP），应用RT-PCR和Western blot技术，分别验证其在人、树鼩和大鼠的肝癌、癌旁及正常肝组织中mRNA和蛋白水平的差异表达情况。实验数据以均数±标准差（x^-±s）表示，采用单因素方差分析。结果初步建成跨种属肝癌差异表达数据集，RT-PCR检测结果显示E-FABP mRNA在人肝癌及其癌旁组织和正常肝组织中的相对表达量分别为0．87±0．14、0．64±0．12和0．67±0．07I在树鼩肝癌及其癌旁组织和正常肝组织中的相对表达量分别为0．87±0．25、0．73±0．19和0．68±0．19；在大鼠肝癌及其癌旁组织和正常肝组织中的相对表达量分别为0．97±0．22、0．78±0．16和0．80±0．13。人、树鼩和大鼠肝癌组织中的E—FABP mRNA表达水平均显著高于癌旁和正常肝组织，F值分别为20．910、3．807、4．482，P值均〈0．05，差异有统计学意义。Western blot检测结果显示E-FABP在人、树鼩和大鼠肝癌组织中的蛋白表达水平均较癌旁和正常肝组织显著上调。结论跨种属肿瘤关键基因筛选策略可能有助于发现肝癌关键基因，E—FABP有可能是影响肝癌发生和发展的重要分子之一。

Objective To evaluate the utility of the cross-species screening strategy for investigating key molecule（s） involved in onset and progression of hepatocellular carcinoma （HCC）. Methods HCC- related molecule data from our previous studies and in the literature were collected to establish a cross-species dataset. Tissue samples of HCC, non-HCC surrounding liver （para-HCC）, and normal liver that were collected from humans, tree shrews and rats. The genes reported to have the most differential expression in HCC were verified by analyzing the mRNA and protein levels by reverse transcription-polymerase chain reaction （RT-PCR） and Western blotting, respectively. Results The cross-species dataset of HCC-related molecules included four genes： epidermal fatty acid-binding protein （E-FABP）, liver （L）-FABP, tyrosine a-ketoglutarate transaminase （TKT）, and cytokeratin （CK8）. In humans, E-FABP mRNA expression was significantly higher （P 〈 0.05） in HCC （0.87 ± 0.14 vs. para-HCC： 0.64 ± 0.12 and normal liver： 0.67 ± 0.07; F=20.910）. Similar results were obtained in tree shrew （HCC： 0.87 ± 0.25 vs. para-HCC： 0.73 ± 0.19 and normal liver： 0.68 ＋ 0.19; F=3.807） and rat （HCC： 0.97±0.22 vs. para-HCC： 0.78±0.16 and normal liver： 0.80 ± 0.13;F=4.482）. The Western blotting analyses revealed a similar statistically signticant trend. Conclusions The cross-species screening strategy for tumor genes may represent a feasible and convenient process of identifying key molecule（s） for human HCC. E-FABP may be a particularly crucial molecule for hepatocarcinogenesis.