ML-239 is an inhibitor of cancer stem cells, displaying greater than 23-fold selective inhibition of a breast cancer stem cell-like cell line (EC50 = 1.18 μM) over an isogenic control cell line (EC50 = 27.6 μM). It is also toxic to the breast carcinoma cell line MDA-MB-231. ML-239 alters the expression of genes in the MAPK, NF-κB, and inflammatory cytokine pathways. It is stable in saline and modestly stable in human plasma.
