中文摘要：

化疗耐药是恶性肿瘤患者成功治疗的主要障碍，多种机制参与肿瘤耐药形成。近来研究表明，microRNAs与肿瘤耐药存在相关性，多种实体肿瘤耐药细胞或组织中microRNAs表达异常，修复异常表达的microRNAs可以改善肿瘤细胞的化疗敏感性。通过对耐药细胞或组织microRNAs表达谱进行研究，有利于耐药机制的深入研究，也有利于发现新的分子靶标以筛查化疗敏感患者。

英文摘要：

Drug resistance is major obstacles in the successful treatment of malignant solid tumors. Multiple mechanisms involeve in development of cancer drug resistance. Recent research suggests dysregulation of microRNAs is associated with cancer drug resistance. The profiles of microRNAs in drug resistance cancer cells or tissues are different with sensitivity cells or tissues in various solid tumors. Restoring microRNAs could improve （;hemosensitivity of cancer cells. MicroRNAs expression profiles may provide a critical link for understanding mechanisms involved in ehemoresistance. We can also find a specific nlarker for screening chemosensitivity patients through identification of the mieroRNAs patterns of drug resistance cells or tissues.