Cancer treatment aims to take into account the rules of natural selection to fight against tumors.
About six years ago, Alberto Bardelli fell into a scientific slump. A cancer biologist at the University of Turin in Italy, he had been studying targeted therapies—drugs tailored to the mutations that drive the growth of a tumour. The strategy seemed promising, and some patients started to make dazzling recoveries. But then, inevitably, their tumours became resistant to the drugs. Time and time again, Bardelli would see them relapse. “I stumbled into a wall,” he says. The problem wasn’t the specific mutations, Bardelli realized: it was evolution itself. “Unfortunately, we are facing one of the most powerful forces on this planet,” he says.
Researchers have long understood that tumours evolve. As they grow, mutations arise and populations of genetically distinct cells emerge. The cells that are resistant to treatment survive and expand. No matter what medication physicians apply, it seems, the tumour adapts. And it has been difficult for researchers to unpick this process, because cancer evolves inside the body over the course of years. “We used to say to patients all the time that cancers are evolving in a Darwinian manner, but we didn’t have a huge amount of evidence at our disposal to really formally prove that,” says Charles Swanton, a cancer researcher at the Francis Crick Institute in London.
That is beginning to change. Thanks to advances in sequencing technology and the development of massive collections of samples and clinical data, scientists are piecing together a more precise picture of how cancer evolves, revealing the roots of resistance and, in some cases, finding out how it might be overcome. With a growing arsenal of treatments, biologists are trying to capitalize on these insights.
“Cancer is continuously adapting, therefore we have to do so as well,” Bardelli says. In that spirit, last year he shifted the focus of his lab to studying the evolution of cancer. His team has modelled how colorectal cancers respond to targeted therapies that are given in combinations, potentially revealing ways to prevent the tumour cells from becoming resistant. “We have very exciting data now on the possibility to track and treat evolution,” he says.
Read Full Article: Cancer Therapy: An Evolved Approach – Scientific American
|Read Full Article: Cancer Therapy: An Evolved Approach – Scientific American|