David Cantor writes:
Siddhartha Mukherjee is an oncologist, physician and laboratory scientist whose book captures the excitement of biomedical research and discovery, the wonder at the complexities of cancer and the bodies it inhabits, and the thrill of major advances in knowledge and practice. Without a molecular framework for understanding cancer, he argues, doctors’ ability to intervene against this group of diseases was limited. The major methods of treatment employed before the 1990s were based on questionable premises and used the bluntest of tools: surgery, carried out on the assumption that cancer began locally before affecting other parts of the body; and radiotherapy and chemotherapy, on the assumption that cancers comprise cells that divide more rapidly than the surrounding normal ones. All of this changed with a series of exhilarating breakthroughs in the last decades of the 20th century. Scientists discovered proto-oncogenes and tumour suppressor genes, which either accelerate or inhibit tumour growth, acting as ‘jammed accelerators’ or ‘missing brakes’, as Mukherjee puts it. They learned about the dependence of cancer cells on permanently activated signalling pathways which drive them to divide and grow, and about the capacity of cancer cells to resist death signals, and to metastasise throughout the body. These discoveries opened up a new world of so-called targeted therapy.