Using the transgenic Eμ-myc mouse model of B cell lymphoma, where c-Myc deregulation in pre-B cells models spontaneous B cell lymphoma9,10, we found that the inflammasome in the bone marrow stroma orchestrated constraint of the Ras pathway in trans within hematopoietic stem cells (HSCs) and controlled turnover of stem and progenitor cells in the transformed compartment. Here, MYC is linked to B-cell non-Hodgkin lymphoma.