Opydo-Chanek M, Śladowska K, Blicharski K, Mikeš J, Fedoročko P, Niemeyer U, Mazur L
Anticancer Res. 37 (11) 6355-6361 [2017-11-00; online 2017-10-25]
The oxazaphosphorines, ifosfamide and cyclophosphamide, represent a class of alkylating agents. The aim of the present in vitro study was to compare antileukemic activity of 4-hydroperoxyifosfamide (4-OOH-IF) and 4-hydroperoxycyclophosphamide (4-OOH-CP). The experiments were performed on MOLT-4 and ML-1 cells. The research was conducted using flow cytometry fluorescein diacetate/propidium iodide (PI), fluorescein-conjugated annexin V/PI, CaspGLOW Red Active Caspase-8 and -9, CellEvent™ Caspase-3/7 Green assays, and tetramethylrhodamine ethyl ester test. 4-OOH-IF and 4-OOH-CP distinctly reduced cell viability and triggered apoptosis and necrosis, causing changes in intracellular esterase activity, plasma membrane structure and integrity, caspase activation, and mitochondrial membrane potential. The oxazaphosphorines were responsible for the different antileukemic activities. 4-Hydroperoxyifosfamide appeared to be less cytotoxic against the leukemia cells than 4-hydroperoxycyclophosphamide. MOLT-4 cells were more sensitive to the action of the oxazaphosphorines than ML-1 cells. The findings provide a new insight on the mechanisms of cytotoxic action of 4-OOH-IF and 4-OOH-CP on the human acute lymphoblastic and myeloblastic leukemia cells.