Date Published: 8 June 2018
Olfactory receptor OR51E2 and prostate cancer
A biotech news website has recently speculated about the possible future use of aromatherapy to treat prostate cancer1. Such a headline attracts attention because while aromatherapy has many uses and benefits, it is not usually the first treatment method to spring to mind for the treatment of cancer. Not surprisingly, the article does not discuss relaxing massages with nice smelling essential oils. Instead it describes recently published research about the behaviour of a particular olfactory receptor in prostate cancer cells. Specifically, olfactory receptor OR51E2, which is also known as a Prostate Specific G-Protein Receptor is the subject of a recent study2 by scientists at Duke University School of Medicine, located in the city of Durham, North Carolina, in the USA.
What is the connection with aromatherapy?
It's worth pausing to explain the connection to anyone unfamiliar with some of the specialist vocabulary used in the scientific paper2. Olfactory receptors are also known as odorant receptors. They are found in the cell membranes of olfactory receptor neurons, neurons being nerve cells i.e. a type of cell that forms nervous tissue, which in turn forms the human nervous system. Olfactory receptors are responsible for the detection of odorants, that is compounds that have an 'odor', also called a 'smell' or an 'aroma'. It is the detection of these compounds by the body that leads to the perception or 'sense' of smell, with different odorants smelling different, some pleasant, some not so nice. In the language of biology textbooks, "activated olfactory receptors trigger nerve impulses which transmit information about odor to the brain".
In common English usage many similar words are often used interchangeably despite subtle distinctions between them indicating one or another as slightly more appropriate in any particular context. In this situation words such as 'odor' (Am.Sp), 'odour' (British Sp.), 'aroma', 'fragrance', 'scent' and 'smell' are sometimes used to refer to either or both an olfactory (smell) sensation and a chemical compound, or compounds, capable of giving rise to that sensation. All these words are closely associated with the physical sense of smell, but in different ways. The words 'aroma', 'fragrance' and 'scent' have generally positive connotations of pleasant olfactory experiences such as of flowers, fruits and oils broadly associated with uplifting ones emotions. Conversely, words such as 'smell' and 'odor' are more likely to be associated with 'bad smells' such as waste or drains and the desire for deodorants (to deal with unpleasant body odors).
Research suggesting that an olfactory receptor has an important role in the progression of prostate cancer raises questions about the possibility of a treatment being developed that would be delivered into the body by the patient inhaling a specifically developed chemical substance, i.e. a drug, that could enter the body via the lungs and then the bloodstream before interacting with the specific olfactory receptor for which that that particular drug had been developed. Note that olfactory receptors are not only located in the nasal cavity ('olfactory epithelium'). Other 'ectopic' olfactory receptors are also present in many parts of the body, including the prostate glad in men.
Aromatherapists and other practitioners of natural approaches to health and well-being might stop right there and state that aromatherapy treatments involve the use of natural (often, but not necessarily, organically produced) essential oils: Inhaling synthetic drugs, i.e. chemicals that have been developed in laboratories, is not what is meant by 'aromatherapy'. In addition, it is highly unlikely that most aromatherapists would be able to obtain or prescribe such drugs3. Therefore one might wonder if the GEN News item (30 May 2018) entitled "Could Prostate Cancer Be Treated with Aromatherapy in the Future?"1 is mis-leading. While the title is attention-grabbing, the article itself summarises and refers to the recent paper by Abaffy et.al.2, as is made clear from the opening sentence:
"Treating prostate cancer could one day be as noninvasive as inhaling certain scented compounds." from genengnews.com2
and from the following quotation early in the article:
"When you smell a specific odor, the molecules you inhale go into your bloodstream. So one day, we may be able to use an odorant to cure prostate cancer - though it's not possible yet." genengnews.com quoting Prof Hiroaki Matsunami of Duke University School of Medicine2
That particular news item makes no further reference to aromatherapy, perhaps - rightly or wrongly - assuming readers' understanding of it. It is possible that use of the word 'aromatherapy' in the title has attracted interest and viewers to that webpage, which is useful. Mention of alternative medicine approaches by publications that concentrate on conventional Western medicine helps to draw attention to the existence of other possibilities even if they are not specifically intended for the condition discussed in the article or the example/s given. Acknowledging the existence of other treatment methodologies respects others' approaches which extend to many different styles and systems across the world including, for example, Ayurveda and Traditional Chinese Medicine (TCM).
Why might aromatherapists be interested?
Having made clear that the recent scientific paper referred to in this case does not endorse the use of essential oils to treat prostate cancer, one might ask why aromatherapists might be interested in it. Afterall, understanding of how compounds from essential oils that have evapourated into the air surrounding a person receiving an aromatherapy treatment reach tissues within the person's body via inhalation then delivery via the lungs then through the bloodstream is well-known to those qualified in aromatherapy.
One answer is that during the busy activities of day-to-day life professionals can sometimes take their own knowledge for granted. In the case of health professionals (of whatever type) that can manifest in the form of occasionally over-looking opportunities to help people to more fully engage with treatments by taking the time and effort needed to explain processes and benefits. Most people who have experienced an aromatherapy treatment would probably agree that such treatments feel good. However, some might also fall into the habit of thinking of aromatherapy as merely relaxing or 'skin deep'. Without disparaging the huge benefits of both relaxation and skincare, the use of essential oils in aromatherapy - as opposed to merely carrier oils in a non-aromatherapy massage treatment - brings additional benefits. A useful purpose will be served if articles such as this one, or that in GEN News Highlights last month, act as a gentle reminder to therapists (incl. aromatherapists) to offer information and explanations in addition to physical or other treatments. Of course this is not intended to suggest that everyone would like a detailed tutorial in biochemistry. Discerning how much information to offer to each individual person is one of the many skills involved in providing any personal, and particularly any therapeutic, service. Given that people might appreciate more information than is usually offered, yet time is limited and therapists can find it difficult to know how much to say - especially to a relatively new client, mentioning recent news such as this can be a useful way to find out who is interested in more detailed information and who is not.