Expression of microRNA in 6 types of human cancer cell lines / 中国肿瘤生物治疗杂志

ABSTRACT

Objective:To determine the difference of miRNA expression profiles in 6 types of human cancer cells by microarray technique.Methods:The microarray was prepared,with contained 210 oligonucleotides,including 206 probes complementary with human and mouse miRNA sequences and 4 positive control oligos.MiRNAs were extracted from HeLa(human cervical cancer epithelial cells),MCF-7(human breast cancer cells),A549(human lung adenocarcinoma cells),HT-29(human colonic cancer cells),ES-2(ovarian carcinoma cells),and K562(chronic myelogenous leukemia cells) cells and were labeled with Cy3 for hybridization to the miRNA microarray.The slides were scanned by ScanArrayTMExpress1.0 and images were analyzed by ScanArray3.0 and Cluster3.0;the results were confirmed by Northern blotting and RT-PCR.Results:Totally 115 miRNAs were found to be differentially expressed in the 6 cancer cell lines,with miR-21 expression up-regulated and miR-125b,let-7 expression down-regulated.The expression of miR-17-5p and miR-20a was in cluster and was more higher in ES-2 cells than in other cells.HeLa and MCF-7 cells were located on a single branch of the dendrogram in cluster analysis.Northern blotting showed that both pre-and miR-17-5p expressed in K562,pre-miR-17-5p was weakly expressed in A549 and ES-2 cells,and obvious pre-miRNA expression and weak miRNA expression were noticed in MCF-7,HeLa,and HT-29 cells.RT-PCR showed that expression of pre-miR-17-5p in K562 cells was higher than those in other cells.Expression of miR-21was high in all 6 cell lines and the highest expression was seen in A549 cells.Conclusion:Microarray can be used to detect miRNA expression files in cancer cells,which contributes to the study of the relation between miRNA and tumor.