Mitoxantrone HClS2485

Mitoxantrone induces DNA fragmentation and the proteolytic cleavage of poly(ADP-ribose) polymerase (PARP), a marker of the activation of caspases, in all the patients studied, demonstrating that the cytotoxic effect of mitoxantrone is due to induction of apoptosis. ^[1] Mitoxantrone activates NFkappaB and stimulates IkappaBalpha degradation in the promyelocytic leukemia cell line HL60 but not in the variant cells, HL60/MX2 cells, which lack the beta isoform of topoisomerase II and express a truncated alpha isoform that results in an altered subcellular distribution. ^[2] Mitoxantrone inhibits proliferation of activated PBMCs, B lymphocytes, or antigen-specific T-cell lines (TCLs) stimulated on antigen-presenting cells (APCs) in a dose-dependent manner. Mitoxantrone induces apoptosis of PBMCs, monocytes and DCs at low concentrations, whereas higher doses causes cell lysis