MicroRNAs (miRNAs) are a class of small non-coding RNA molecules (containing ～22 nucleotides),which function in RNA silencing and post-transcriptional regulation of gene expression [1].miRNAs have been reported to play a key role in tumorigenesis [1].Some single nucleotide polymorphisms (SNPs) in miRNA genes can influence the generation or function of miRNAs,and thereby possibly affect tumor growth and development.