Tracking preleukemic cells in vivo to reveal the sequence of molecular events in radiation leukemogenesis

Verbiest, T and Finnon, P and Brown, N and Cruz-Garcia, L and Finnon, P and O'Brien, G and Ross, E and Bouffler, S and Scudamore, C L and Badie, C (2018) Tracking preleukemic cells in vivo to reveal the sequence of molecular events in radiation leukemogenesis. Nature, 32. pp. 1435-1444.

[img]
Preview
Text
11451.pdf - Published Version
Available under License Creative Commons Attribution.

Download (1MB) | Preview

Abstract

Epidemiological studies have demonstrated an increased leukemia incidence following ionizing radiation exposure, but to date, the target cells and underlying mechanisms of radiation leukemogenesis remain largely unidentified. We engineered a mouse model carrying a different fluorescent marker on each chromosome 2, located inside the minimum deleted region occurring after radiation exposure and recognized as the first leukemogenic event. Using this tailored model, we report that following radiation exposure, more than half of asymptomatic CBA Sfpi1GFP/mCh mice presented with expanding clones of preleukemic hematopoietic cells harboring a hemizygous interstitial deletion of chromosome 2. Moreover, following isolation of preleukemic hematopoietic stem and progenitor cells irradiated in their native microenvironment, we identified the presence of Sfpi1 point mutations within a subpopulation of these preleukemic cells expanding rapidly (increasing from 6% to 55% in 21 days in peripheral blood in one case), hence identifying for the first time the presence of such cells within a living animal. Importantly, we also report a previously undescribed gender difference in the phenotype of the preleukemic cells and leukemia, suggesting a gender imbalance in the radiation-induced leukemic target cell. In conclusion, we provide novel insights into the sequence of molecular events occurring during the (radiation-induced) leukemic clonal evolution.

Actions (Repository Editors)

View Item View Item