Screening For Mutation On MiRNAs In CRCs

CRC (colorectal cancers) is one kind of most common cancer,and it'smorbidity and mortality have increasedgradually every year in our country. The knowledge formolecular mechanisms underlying its initiation and progression has significant meaning for the prevention and treatment of this disease. miRNAs are new identified RNA genes and are undergoing intensive investigation. They play a vital role in the development of organisms and balance maintenance of the cells. In many kinds of diseases,the expression patterns of miRNAs are altered. The changed miRNAs participate and contribute to the whole process,which is also true in the case of CRCs, but the factorsaffectingthe expression of miRNA are largely unknown..In the cancer tissues of CRCs patients and CRCs cell lines(SW480, DLD-1, RKO), we have identified a few mutations on the miRNAs by cloning and sequencing. For all of the samples,there are two unreported single nucleotide mutation sites with base A changed to G on the hsa-mir-532,.A SNP site on hsa-mir-618 appears only having base G alternative to base T. While the VNTR sequence before hsa-mir-137 expands in the case of RKO cell. Those mutations may impact on the folding and maturation of miRNA so as to alter the relationship between miRNAs and their targets. As a result, those mutations may contribute to CRCs developmental progress.