中文摘要：

MicroRNA（miRNA）是一类含21～25个核苷酸长度的单链小分子RNA，其在细胞生长和发育过程的调节中起到了多重作用．miRNA的突变或异位表达与多种肿瘤相关。电离辐射可以诱导miRNA的改变，从而产生致癌或抑癌效果，而且辐射诱导的miRNA表达变化还显示出细胞特异性和性别特异性。

英文摘要：

MicroRNA （miRNA）are noncoding RNA of 21-25 nucleotides that act as post-transcriptional regulators of gene expression, it plays a multiple role in the regulation of cell growth and development, miRNA mutation or ectopia expression is associated with a variety of tumor. Ionizing radiation which has a carcinogenic or tumor suppressive effect induces changes in miRNA, miRNA expression changes induced by radiation are also cell-specific and gender-specific.