Wong Queenie W-L, Lung Raymond W-M, Law Priscilla T-Y, Lai Paul B-S, Chan Kathy Y-Y, To Ka-Fai, Wong Nathalie
Department of Anatomical and Cellular Pathology at the Li Ka-Shing Institute of Health Sciences, The Chinese University of Hong Kong, SAR Hong Kong, China.
Gastroenterology. 2008 Jul;135(1):257-69. doi: 10.1053/j.gastro.2008.04.003. Epub 2008 Apr 11.
BACKGROUND & AIMS: Recent studies have emphasized causative links between microRNA (miRNA) deregulations and cancer development. In hepatocellular carcinoma (HCC), information on differentially expressed miRNA remained largely undefined.
Array-based miRNA profiling was performed on HCC cells that were derived from chronic carriers of hepatitis B virus (HBV) and hepatitis C virus (HCV), and nonviral-associated patients. Specific microRNA (miR)-223 and miR-222 deregulations were verified in an independent series of tumors. The functional effect of miR-223 was examined further. An integrative analysis of messenger RNA (mRNA) array with in silico predictions defined potential downstream targets of miR-223. A luciferase reporter assay was conducted to confirm target association.
Distinct up-regulations of miR-222, miR-221, and miR-31, and down-regulations of miR-223, miR-126, and miR-122a were identified. Further investigations suggested the highly deregulated miR-223 and miR-222 could unequivocally distinguish HCC from adjacent nontumoral liver, irrespective of viral associations (P <or= .0002). Re-expression of miR-223 in HBV, HCV, and non-HBV non-HCV-related HCC cell lines revealed a consistent inhibitory effect on cell viability (P < .01). Integrative analysis further implicated Stathmin 1 (STMN1) as a downstream target of miR-223. A strong inverse relationship between STMN1 mRNA and miR-223 expressions was shown (P = .006). A substantial reduction in STMN1 protein was further demonstrated upon restoration of miR-223 expression in HCC cell lines. We further showed that miR-223 readily could suppress the luciferase activity in reporter construct containing the STMN1 3' untranslated region (P = .02).
Our study revealed specific miRNA differential expressions in HCC and underscores the potential importance of miR-223 down-regulations in the development of HCC.
近期研究强调了微小RNA（miRNA）失调与癌症发展之间的因果联系。在肝细胞癌（HCC）中，关于差异表达miRNA的信息仍大多未明确。
对源自乙型肝炎病毒（HBV）和丙型肝炎病毒（HCV）慢性携带者以及非病毒相关患者的肝癌细胞进行基于芯片的miRNA谱分析。在另一组独立肿瘤中验证了特定微小RNA（miR）-223和miR-222的失调情况。进一步研究了miR-223的功能作用。通过对信使核糖核酸（mRNA）芯片与计算机预测结果进行综合分析，确定了miR-223潜在的下游靶点。进行荧光素酶报告基因检测以确认靶点关联。
发现miR-222、miR-221和miR-31明显上调，miR-223、miR-126和miR-122a下调。进一步研究表明，无论病毒关联情况如何，高度失调的miR-223和miR-222都能明确区分肝癌与相邻的非肿瘤肝脏组织（P≤0.0002）。在HBV、HCV以及非HBV非HCV相关的肝癌细胞系中重新表达miR-223，显示出对细胞活力的一致抑制作用（P<0.01）。综合分析进一步表明，Stathmin 1（STMN1）是miR-223的下游靶点。STMN1 mRNA与miR-223表达之间呈现出强烈的负相关关系（P = 0.006）。在肝癌细胞系中恢复miR-223表达后，进一步证明STMN1蛋白显著减少。我们还进一步表明，miR-223能够显著抑制含有STMN1 3'非翻译区的报告基因构建体中的荧光素酶活性（P = 0.02）。
我们的研究揭示了肝癌中特定的miRNA差异表达，并强调了miR-223下调在肝癌发生发展中的潜在重要性。
