During the COVID-19 pandemic, there was a huge rise in misinformation about medicines, among other matters. It also changed people’s engagement with podcasts. For myself, the pandemic flagged up the existence of the Aural Apothecary, which features more than 50 episodes (and growing) of podcast interviews about all things medicines-related.
A recent episode on the podcast featured Liz O’Riordan; a breast-cancer surgeon who was herself diagnosed with breast cancer and now spends a huge amount of time helping others by debunking misinformation and tackling myths about cancer and its treatment. In April 2023, her call on Twitter for people to send in posts about dubious cancer cures makes for depressing reading — there appear to be many potential ‘natural cures’, some of which are dangerous as well as ineffective. The thread indicates people’s appetite to experiment on themselves, by attempting a cure with unproven remedies, even when their condition is serious and the risks of getting it wrong are so high.
A purely scientific mind might wonder why people would make important health decisions based on hearsay and anecdote, rather than data and evidence. It is perhaps hard to answer this without subjective experience, but we might consider that what makes us human is that stories, rather than science, can take precedence in our everyday experience, especially when we face difficult choices. As a result, my focus this month is on primary studies that investigate potential cancer cures originating from natural sources.
The first paper, published in RPS Pharmacy and Pharmacology Reports, examines the anticancer effect of Cissus quadrangularis (CQ) on human glioblastoma cells. CQ, the authors describe, is a vining plant native to south Asia and Africa, extracts of which contain a range of promising constituents, such as phytosterols, ascorbic acid, triterpenoids, and so on. The authors selected glioblastoma cells based on the need to find better treatment for glioblastoma multiforme, an aggressive and difficult-to-treat brain tumour. Using a range of experiments, the authors illustrate the potential anticancer properties of CQ through its ability to inhibit glioblastoma cell viability and migration, potentially through mitochondrial fragmentation, apoptosis, suppression of cell cycle progression, endoplasmic reticulum stress, as well as downregulation of pro-survival signalling pathways. Of course, these findings can only signal that more work awaits to establish the in vivo effects of CQ and its therapeutic potential in humans.
The second paper, published in the Journal of Pharmacy and Pharmacology, is a study of the anticancer properties of compound shougong powder, a traditional Chinese medicine formulation, which the authors indicate is of both plant and reptile origin. The work focuses on hepatocellular carcinoma (HCC), a leading cause of cancer death. The authors state compound shougong powder has already achieved “outstanding” results in clinical trials of a range of other cancers. Using chromatographic methods, they first confirm the active ingredients of their compound shougong powder to include hypericin, ginsenoside Rb1, emodin and emodin methyl ether. Then, using a range of methods, the authors show that compound shougong powder has inhibitory potential in both HCC cell lines, as well as an in vivo tumour model in mice, proposing it does so via interference with the DNA damage-repair pathway.
The third paper that caught my attention, also published in the Journal of Pharmacy and Pharmacology, focused on propolis, which the authors describe as “a natural product composed of a mixture of resins, plant exudates and tree barks, added to organic secretions from the metabolism of the Apis mellifera bees, therefore classified as opotherapic”. The organic secretions from bees might also be thought of as bee glue. Focusing on ovarian cancer, another difficult-to-treat malignancy, the authors studied Brazilian red propolis extract (BRPE). However, rather than merely investigating the biological anti-tumour effects of ‘free’ BRPE, highlighting the need to work on the drug delivery aspects of this product, they also created nanostructured systems for encapsulation of BRPE, which they included in their assessment of its activity in ovarian cancer cells. I include this paper here because the authors rightly highlight the need to consider not just biological activity of natural products, but also their physicochemical properties, such as low solubility, bioavailability, instability and short half-life, which are also important when assessing the application of natural products in cancer therapeutics.
The final paper I read, published in RPS Pharmacy and Pharmacology Reports, was a review paper looking at bioactive compounds from marine sources, including in the treatment of cancer. What I found interesting is the inclusion of a whole range of organisms and derivatives, including snails, corals, algae, sponges and tunicates in this review. It’s worth a read, if for no other reason than to help us appreciate the importance of marine life in general, if we didn’t already.
How awe-inspiring that we continue to learn that products from a breadth of natural sources, not just plant but reptile, bee and marine-life, can have therapeutic potential. But potential is the operative word. A pharmacist would know, of course, that it is one thing to extract, characterise and then test substances derived from nature in cell lines and animal models, but quite something else to formulate, deliver and prove their efficacy in large-scale randomised clinical trials.
Perhaps this adds further weight, if it was ever needed, to the important role that pharmacists play in educating patients, especially those with cancer. For those training to be a pharmacist, using stories to convey science would be a great place to start.
Parastou Donyai is chief scientist at the Royal Pharmaceutical Society
