They applied equal concentrations of commercial Somalian frankincense oil from the Boswellia carteri tree, without modifying it, to the in vitro cells. They didn’t want to focus their research on finding the specific chemical composition of frankincense oil nor determining best dosages, since some previous research showed that total frankincense extract is more powerful than pure individual boswellic acids (the active ingredients in frankincense). But for future research, they noted, such steps will have to be taken to gauge their effect on tumor suppression.
The scientists performed gene expression analyses to see how frankincense oil stifles bladder cancer cells. They found that the oil suppresses cancer cell growth by halting cell cycle progression and stimulating many natural cell-death pathways.
The team found that four other oils kill both cancerous and normal bladder cells. These were sandalwood oil (Santalum album), balsam fir oil (Abies balsamea), palo santo oil (Bursera graveolens), and tsuga oil (Tsuga canadensis).
The frankincense tree is native to Africa, India, and the Middle East, and frankincense oil has previously been shown to have many medicinal benefits.
About two-thirds of bladder cancer sufferers are men. In the United States, bladder cancer is the fourth most common type of cancer in males; in Britain, it is the seventh-highest cause of death among men.
“Frankincense oil,” Lin said, “may represent an inexpensive alternative therapy for patients currently suffering from bladder cancer.” He emphasized, however, that experiments need to be performed using additional bladder cancer cell lines and animal models in order to confirm the team’s observations.