beta-bisabolene and Breast-Neoplasms

The essential oils from Commiphora species have for centuries been recognized to possess medicinal properties. Here, we performed gas chromatography-mass spectrometry on the essential oil from opoponax (Commiphora guidotti) and identified bisabolene isomers as the main constituents of this essential oil. Opoponax essential oil, a chemical component; β-bisabolene and an alcoholic analogue, α-bisabolol, were tested for their ability to selectively kill breast cancer cells. Only β-bisabolene, a sesquiterpene constituting 5% of the essential oil, exhibited selective cytotoxic activity for mouse cells (IC50 in normal Eph4: >200 µg/ml, MG1361: 65.49 µg/ml, 4T1: 48.99 µg/ml) and human breast cancer cells (IC50 in normal MCF-10A: 114.3 µg/ml, MCF-7: 66.91 µg/ml, MDA-MB-231: 98.39 µg/ml, SKBR3: 70.62 µg/ml and BT474: 74.3 µg/ml). This loss of viability was because of the induction of apoptosis as shown by Annexin V-propidium iodide and caspase-3/7 activity assay. β-bisabolene was also effective in reducing the growth of transplanted 4T1 mammary tumours in vivo (37.5% reduction in volume by endpoint). In summary, we have identified an anti-cancer agent from the essential oil of opoponax that exhibits specific cytotoxicity to both human and murine mammary tumour cells in vitro and in vivo, and this warrants further investigation into the use of β-bisabolene in the treatment of breast cancers.

Topics: Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Breast Neoplasms; Caspases; Commiphora; Female; Gas Chromatography-Mass Spectrometry; Humans; MCF-7 Cells; Mice; Monocyclic Sesquiterpenes; Oils, Volatile; Phytotherapy; Plant Extracts; Sesquiterpenes

The biological activities and the determined major volatile components in the Magnolia grandiflora and M. virginiana flowers extracts were compared. Volatile components were detected in the essential oil by dynamic headspace sampling (HS). 2-Phenylethanol (40% and 61%) was found as the main constituent in the essential oil and HS samples of M. virginiana, respectively. In the M. grandiflora oil sample, (E,E)-farnesol (18%) and 2-phenylethanol (10%) were found as main constituents, whereas germacrene D (17%) and β-bisabolene (17%) were the main components of the HS sample. The essential oil in M. virginiana displayed a moderate antioxidant activity relative to vitamin E, whereas both essential oils were active against human lung carcinoma and breast carcinoma cell lines, even at concentrations higher than 200 µg mL(-1).

Topics: Antineoplastic Agents, Phytogenic; Antioxidants; Breast Neoplasms; Cell Line, Tumor; Farnesol; Female; Flowers; Humans; Lung Neoplasms; Magnolia; Monocyclic Sesquiterpenes; Oils, Volatile; Phenylethyl Alcohol; Sesquiterpenes; Sesquiterpenes, Germacrane; Species Specificity