Resistance to cancer drugs: A new genetic explanation

Cancer drugs can burn through tumors like a wildfire, killing off the vast majority of malignant cells. But a few stubborn cells often end up surviving, seeding a recurrence of the disease. The prevailing theory behind this drug resistance is built on natural selection: Among the vast and genetically diverse population of cancer cells in a tumor, some have random mutations that help these cells survive an onslaught.

“But this is not the full picture,” said Yogesh Goyal, a cancer researcher at Northwestern University. Goyal and his colleagues at the University of Pennsylvania demonstrated in a series of experiments that cancer cells can survive treatments just by having certain genes turned on, even if they were nearly genetically identical to cancer cells that died but had activated different genes.

“We think this work stands to really change how we think about therapy resistance,” said Arjun Raj, the study’s co-senior author and a bioengineer at the University of Pennsylvania.