The effect of CBG (BDS) botanical cannabinoid extract on MCF‐7 human breast carcinoma cells

Abstract

Recently the cannabinoid pharmacology has received attention in cancer research (Alexander et al., 2009). The present study investigated the potential anti‐tumour activity of CBG (BDS), a botanical cannabinoid extract on breast tumour cells.MCF‐7 cells (American Type Culture Collection) were grown and maintained in RPMI 1640 medium plus 10% fetal bovine serum at 37°C, 5% CO2. The cells were plated in 96‐well culture plates at a density of 1×104 cells/well and allowed to adhere at 37°C for 24 hours. The following day, various doses of extract or vehicle in the absence and presence of AM251, SR144528 and capsazepine, were added to the cells and further incubated for 4 days. Then the supernatant was removed and MTT (3‐(4,5‐dimethylthiazol‐2‐yl)‐2, 5‐diphenyltetrazolium bromide) was added for 4 hours. The ability of cells to form formazan crystals by active mitochondrial respiration was determined after dissolving the crystals in DMSO. Cytotoxicity was expressed as a relative percentage of the absorbance measured at 540 nm.CBG (BDS) extract induced dose‐dependent cytotoxic effect (IC50 of 0.096 mg/ml). Pre‐treatment with AM251, SR144528 and Capsazepine, CB1, CB2 and TRPV1 receptor antagonists, respectively, did not reverse the cytotoxicity afforded by CBG (BDS). Single application of antagonists alone or vehicle did not affect the survival rate of the MCF7 cells.The data suggest the unlikely involvement of CB1, CB2 and TRPV1 receptors in mediating CBG (BDS)‐induced cytotoxicity.We thank GW Pharmaceuticals for providing cannabinoid extracts.