The human microbiome is the subject of a burgeoning field of research. The effect of gut microflora, and especially bacteria, has in the last few years been linked to anxiety, depression, gastrointestinal and autoimmune diseases, and numerous other disorders.Having the appropriate gut microflora has been correlated to everything from high quality sleep, to lengthening the human lifespan. One of the newest surprises it that gut microbiota can play a role in cancer – yes, even though cancer arises from nothing other than our own cells. The way that it influences cancer is complex, and not completely understood, but several key ideas have been proposed.
A new era in medical science has dawned with the realization of the critical role of the “forgotten organ,” the gut microbiota, in health and disease. Central to this beneficial interaction between the microbiota and host is the manner in which bacteria and other microorganisms contained within the gut communicate with the host’s immune system and participate in a variety of metabolic processes of mutual benefit to the host and the microbe.
One recent finding is that checkpoint inhibitor (CPI) anti-cancer immunotherapies get a massive boost from the presence of certain bacteria. Scientists believe that this is because these specific bacteria activate an immune pathway in the body that allows T cells to become activated, priming them to seek out and destruct cancer cells. The effect is all-or-nothing and does not work for most people, but it can cure some cancer patients quickly, safely and with minimal side-effects. CPI immunotherapies are a miracle for some people, albeit only the lucky ones who respond to treatment.
Of course, findings like this are spurring the growth of companies looking to cash in on the new developments, as well as save lives. In addition, they are also spurring further growth of the research sector. The very fact that such an incredible treatment works only for a select few poses a new challenge: can we find a way to make this work for everyone, including those of who fall into the “unlucky” category? How can the approach be generalized, and might there even be a bacterium (or other organism) that can help the anti-cancer bacteria do their job, effectively extending the realm of treatment to many more patients?
Finally, it’s worth noting that while this technology is still in its infancy, it already poses challenges to the FDA and any other government-sanctioned bodies that are responsible for regulation. For starters, how does one patent a living organism? How much information needs to be shared with clinicians and scientists, balancing the need for companies to retain information rights vs. the need to for physicians to understand what they’re doing to people? And how can we even be sure that we’ve got the right mechanistic explanation, when several different pathways and completely different mechanisms may simultaneously be at work, contributing to the overall efficacy of the treatment?
These questions, and others, will have to be addressed as this research uncovers more promising treatments and complex connections between out gut microflora and our health.