Opinion piece by Dr. Jumi Popoola
Not the Cancer talk!
In many settings, Cancer is the big “elephant in the room”. It’s the thing no one likes to talk about even though most of us have encountered it either through a family member or a friend. For those of us that have been lucky, we’re left desperately hoping never to come across it in our lifetime.
Cancer is one of the major causes of global death in the non-communicable disease category. It is a genetic disease that is globally prevalent, the cause(s) of which is/are yet to be fully understood. There are ongoing research efforts to understand the genetic changes associated with the development and progression of cancer. This research is fuelling drug discovery approaches, driving clinical trials and ultimately resulting in the development of new cancer drugs. But why aren’t these new drugs always equally potent in all treated individuals? Clearly some patients benefit more than others, so there has to be a clear definition on which subset of individuals will benefit from a drug and which subset of individuals will not.
How will this distinction be made?
Advances in medical technologies are reshaping the way research is now being conducted. Sequencing of tumours (whole genome or targeted regions of the genome) which took months in the past, is now possible in a matter of days. This ultimately provides comprehensive “maps” of different cancer genomes and the multiple genetic variations contained in them. From this information, it is possible to categorize genetic signatures associated with different cancers from individuals or groups of people so as to better understand the diversity of cancers.
How do these signatures help improve treatment of cancers?
Simple! New drugs can be developed to target these tumour signatures. The tumour signature will guide patient stratification and determination of patient eligibility to access newly developed drugs for treatment, as well as inclusion of these patients in clinical trials for the drug to be approved if successful in the trial. With this, drug efficacy is improved and patients are able to benefit from drugs designed with a clear understanding and inclusion of their genetic signature. In addition, the drugs will be better tolerated and therefore have lesser side effects in these patients. Some classic examples are the well-studied variants in the HER2 gene that are associated with better response to breast cancer treatment drug Herceptin as well as in the BRAF gene, which are associated with better response to melanoma treatment drug Vemurafenib
How are governmental health bodies tapping into this approach towards achieving personalised medicine in their respective countries?
Some countries have established nation-wide research into sequencing the genomes of their citizens e.g. the 100K Genomes Project in the United Kingdom, the International HapMap Project, The GoNL project in The Netherlands, The GAsP Project in Asia, The All-of-Us Project in the U.S.A, to mention but a few. These initiatives are aimed at understanding the genomic drivers of health as well as disease in their respective populations. The data obtained is extremely useful for the discovery of novel drug targets as well as improved diagnosis of diseases, including cancer. Other countries should emulate these pace-setting countries to enhance the understanding of the genetics and genomic profiles of their citizens so as to tailor healthcare modalities (including drug development) to the people.
What’s the catch?
There’s a caveat to (almost) everything in life, right? Cancers are “beasts” that are constantly trying to find ways to evolve and evade the drug targeting their growth by developing alternative pathways to survive even in the presence of that drug. Therefore, it is important to keep up with the ever-changing face of cancer evolution in order to be able to proffer therapeutic solutions in a timely manner and to achieve the greatest drug efficacy for the management and treatment of cancer.