IDH2 mutation accelerates TPO-induced myelofibrosis with enhanced S100a8/a9 and NFκB signaling in vivo.

INTRODUCTION

mutation is an unfavorable prognostic factor in patients with primary myelofibrosis (PMF) but its effect on myelofibrosis (MF) remains largely unclear.

METHODS

In this study, we aimed to elucidate the roles of mutation in the development and progression of MF by transcriptomic and molecular techniques using the transgenic mice.

RESULTS

We found that thrombopoietin (TPO)-overexpressed ( + TPO) mice had accelerated progression to MF, compared with TPO-overexpressed wild (WT + TPO) mice, showing activation of multiple inflammatory pathways, among which nuclear factor κB (NFκB) was the most significantly enhanced. Single-cell transcriptomes of the marrow cells in early MF showed that expression was mainly confined to neutrophil progenitors in the WT + TPO mice, but highly expressed in several types of myeloid precursor cells, including the megakaryocyte progenitors in the + TPO group. Furthermore, mice at age of 18 months had larger spleens, increased expression, and elevated serum S100a8/a9 levels compared with WT mice. PMF patients with mutations had higher bone marrow plasma S100A8/A9 levels than those without mutations.

CONCLUSION

Overall, our findings showed that mutation induced proinflammatory effects, which further exacerbated MF, as evidenced by the increase in S100a8/a9 levels and NFκB hyperactivation in + TPO mice.