Investigation of the chemopreventive potential of neem leaf subfractions in the hamster buccal pouch model and phytochemical characterization.

Chemoprevention by medicinal plants has evolved as a practical strategy to control the incidence of cancer. Azadirachta indica (neem) containing various bioactive components is a promising candidate for chemoprevention. The present study was undertaken to evaluate the chemopreventive efficacy of the bioactive subfractions ethyl acetate chloroform insoluble fraction (ECIF) and the methanol ethyl acetate insoluble fraction (MEIF) following activity-guided fractionation of neem leaf extract. Analysis of the mechanism of chemoprevention revealed multitargeted mode of action that involved modulation of xenobiotic-metabolizing enzymes, inhibition of cell proliferation, induction of mitochondrial apoptosis, and abrogation of NF-κB signaling. HP-TLC, GC-MS and LC-MS analyses indicated the presence of several polar phytochemical entities in the neem leaf subfractions that might be responsible for their potent chemopreventive efficacy.