Genetic network profiles associated with established resistance to ionizing radiation in acute promyelocytic leukemia cells and their extracellular vesicles.

Radiation-resistant acute promyelocytic leukemia (APL) cells present challenges to treatment, and the acquisition of resistance to ionizing radiation (IR) is a matter of clinical concern. However, little information is available on the behavior of radio-resistant APL in terms of gene expression profiles and intercellular communication. In this study, cDNA microarray and RT-PCR were used to analyze the intracellular genetic network and extracellular vesicles (EVs), respectively, in the established radio-resistant HL60 (Res-HL60) cell line. Significant changes in the expression of 7,309 known mRNAs were observed in Res-HL60 relative to control. In addition, 7 mRNAs were determined as targets because significant changes in the expression were observed using Ingenuity analysis software, confirming the quantitative RT-PCR. However, EVs from Res-HL60 cells did not include these target molecules. These results suggest that radio-resistant APL is regulated by the expression and suppression of specific molecules, and these molecules are not transferred between cells by EVs.