Drug-tolerant persister cells in cancer: the cutting edges and future directions

Abstract

Drug-tolerant persister (DTP) cell populations were originally discovered in antibiotic-resistant bacterial biofilms. Similar populations with comparable features have since been identified among cancer cells and have been linked with treatment resistance that lacks an underlying genomic alteration. Research over the past decade has improved our understanding of the biological roles of DTP cells in cancer, although clinical knowledge of the role of these cells in treatment resistance remains limited. Nonetheless, targeting this population is anticipated to provide new treatment opportunities. In this Perspective, we aim to provide a clear definition of the DTP phenotype, discuss the underlying characteristics of these cells, their biomarkers and vulnerabilities, and encourage further research on DTP cells that might improve our understanding and enable the development of more effective anticancer therapies. Despite improved effectiveness, most systemic cancer therapies are not curative and most patients will develop acquired resistance that often cannot be explained by the emergence of specific genomic alterations. In this Perspective, the authors describe the potential role of a small population of tumour cells, termed drug-tolerant persister cells, that are able to survive therapy and, on continued treatment exposure, develop stable mechanisms of resistance to systemic therapies.