The unique expression of non-coding microRNAs in radioresistant fraction of acute promyelocytic leukemia, HL60 cell

A one of general treatments of patient with acute promyelocytic leukemia (APL) is performed a high dose rate of total-body irradiation therapy. However, the appearance of radioresistant cell that is rarely expressed induces a harmful outcome even performing radiotherapy. We have been established a radioresistant APL cell model (Resistant type), and some characteristics was clarified. But little is known as to the micro RNAs (miRs) expression profile in this cell. In the present study, we analyzed on the expression profile of miRs included in small RNAs using miRNA microarray, The focused miRs that is enabled to investigate by normalization was 1187 molecules. Among these miRs, 27 miRNAs (10 up-regulated miRs and 17 down-regulated miRs) in Res-HL60 showed a p-value < 0.05, Fold change > 1.5 or Fold change < 0.66 in comparison to Wt-HL60. In addition, five miRs were reproducible in RT-qPCR (miR-146a-5p, miR-30c-1-3p, miR-671-5p, miR-610, miR-3675-5p). miRNA-target gene regulation networks were looked for the five miRNAs using OmicsNet 2.0. Interestingly, the five miRNAs were Superoxide Dismutase 2 (SOD2) mRNA. These results were suggested that radioresistant leukemia cell acquires antioxidant system through from specific miRs endogenously. Human acute promyelocytic leukemia cell line HL60 was prepared after frequent irradiation (4Gy X-irradiation ×4 fractions per 4 weeks) with confirmed radiation-resistance characteristics. The extracted total RNA in wild type cell and radiation-resistant cell were performed micro RNA microarray and calculate the expression of micro RNAs.