According to scientists, in the future, cancer will be treated not as an organ-specific disease but will depend on understanding the genes that work defectively and lead to cancer.
“Drugs are developed around targets (genetic/protein pathways) and generally not around specific organs. There is increasing anecdotal evidence that actionable mutations found in cancers suggest repurposing drugs that have hitherto not been used to treat cancers of the tissue of origin,” says Dr Vijay Chandru, chairman and CEO of Strand Life Sciences.
Thus, clinical strategy may need to go beyond the obvious, he points out.
Dr Kalyanasundaram Subramanian, their chief scientific officer adds, “Another parallel here is with HIV, where usually a cocktail of drugs are used to treat the disease. Similarly, in cancer it is likely that in the future, treatment will be multi-pronged by attacking the cancer on various fronts based upon the mutation profile.”
Do Indian scientists agree with the shift in thought? Dr Chandru says, “Yes, particularly since our ability to find these mutations and match them to therapeutic strategies is growing by leaps and bounds. Advances in technology of genome sequencing and rapid reduction in costs are primary drivers.”
Cancer is a scary disease and the costs of treatment can be debilitating for individuals and society, he says. It is estimated, for example, that less than 10 per cent of patients who receive chemotherapy for lung cancer benefit, while administration of other anti-cancer agents that may benefit them are delayed, he explains.
Can genetic diseases like diabetes benefit from the above strategies and what will the future be like? Dr Chandru thinks, “Pharmacogenomics (dosage sensitivity, adverse reactions, etc) will likely extend broadly to other disease areas.
Certain subtypes of diabetes can also benefit from diagnosis of mutations in the genome.” Leading neuroscientists have suggested that subtyping diseases may be the future and often use the analogy with cancer, he says.
Dr Subramanian, on the other hand, thinks, “I will go even further and say that in the not-so-distant future every disease will be addressed this way and every patient will be treated in a personalised manner for every disease.”
Dr Ryan B Jensen, assistant professor of therapeutic radiology at Yale School of Medicine, New Haven in Connecticut, USA, says, “The future of cancer research is mostly going to be understanding the unique combination of genes that are mutated in each type of cancer and developing drugs that specifically target these genetic pathways instead of specific organs.”
This will move clinicians away from categorising cancer as organ specific and instead, a lung tumour may have the same genetic mutations as a colon tumour and treated with the same drug, he explains.
The current standard of care is to treat cancer in an organ-centric manner and hence breast cancer is treated differently when compared to lung or colon cancer, he adds.