Model illustrating how multiple, converging pathways may lead to t-MN. Left, various
predisposing factors that may influence whether a patient develops t-MN. A patient may
have no predisposing factors, have an inherited mutation (predisposing them to aberrant
DNA repair), have a preexisting somatic mutation (CHIP), or have an aberrant BM
microenvironment (due to aging and/or chronic inflammation). Middle, how multiple cycles
of cytotoxic therapy may promote clonal expansion of cells with preexisting and/or newly
acquired mutations and alter the BM microenvironment, possibly via therapy-induced
senescence. Together, this creates permissive conditions for malignant transformation of
hematopoietic cells. Right, how these changes converge to deregulate the DNA damage
response and cell-cycle checkpoint, as well as enhance metabolism and survival,
ultimately leading to t-MN.