Am J Cancer Res. 2012;2(4):414-33. Epub 2012 Jun 28.
Disturbances in microRNA expression by epigenetic alterations and mutations may promote not only tumorigenesis but also tumor aggressiveness, invasion, metastasis, and resistance to chemotherapy and radiotherapy. Several studies have profiled microRNA expression in normal and tumorigenic tissues, demonstrating a unique microRNA signature, which can be used as a marker for cancer diagnosis and prognosis. This review discusses the importance of microRNAs as regulatory biomolecules involved in cancer, focusing on microRNAs related to cancer invasion, metastasis, epigenetic alterations, chemoresistance, and radioresistance. The identification of both differentially expressed microRNAs in tumors and their target genes provides new tools for gene therapy; the re-expression of microRNAs silenced by cancer development or the silencing of oncogenic microRNAs can be effective in the blockade of cancer-related cell proliferation.
表观遗传改变和基因突变引起的 microRNA 表达紊乱不仅可能促进肿瘤发生，还可能促进肿瘤的侵袭、转移、耐药性以及对化疗和放疗的抵抗。一些研究已经对正常组织和肿瘤组织中的 microRNA 表达进行了分析，结果表明存在独特的 microRNA 特征，可作为癌症诊断和预后的标志物。本文讨论了 microRNAs 作为参与癌症的调节生物分子的重要性，重点介绍了与癌症侵袭、转移、表观遗传改变、化疗耐药性和放疗耐药性相关的 microRNAs。鉴定肿瘤中差异表达的 microRNAs 及其靶基因为基因治疗提供了新的工具；重新表达因癌症发生而沉默的 microRNAs 或沉默致癌 microRNAs 可有效阻断与癌症相关的细胞增殖。
