LY86, LRG1 and PDE9A genes overexpression in umbilical cord blood hematopoietic stem progenitor cells by acute myeloid leukemia (M3) microvesicles.

Background: Microvesicles as a new device of cell-cell communication are potentially able to induce some phenotypes and genotypes of an origin cell in a target cell. We evaluate the role of leukemia microvesicles on the leukemia stem cells (LSCs)-specific genes expression in healthy hematopoietic stem progenitor cells (HSPCs).

Methods: HL-60 and NB-4 cell lines were selected for microvesicles isolation by ultracentrifugation. Healthy HSPCs were obtained by magnetic association cell sorting (MACS) and CD-34 micro-beads from umbilical cord blood samples and then, were treated with 20 and 40 μg/ml leukemia microvesicles for 10 days, respectively. , and genes expression as LSC specific genes were analyzed by QRT-PCR. Surface CD-34 antigen as stemness marker was measured by flow cytometry technique.

Results: Healthy HSPCs showed a significant increase in LSC specific genes expression after treatment with both 20 and 40 μg/ml leukemia microvesicles at day 10. All studied groups showed more than 70% surface CD-34 antigen at the last day of experiment which proved HSPCs stemness.

Conclusion: Our results suggest that healthy HSPCs can be transformed genetically by leukemia microvesicles to over express LSC specific genes. This may be further evidence of leukemia-like transformation by leukemia microvesicles.