Targeting cancer-associated fibroblasts: Challenges, opportunities and future directions

Cancer-associated fibroblasts (CAFs) are a common cell in the tumour microenvironment with diverse tumour -promoting functions. Their presence in tumours is commonly associated with poor prognosis making them at-tractive therapeutic targets, particularly in the context of immunotherapy where CAFs have been shown to pro-mote resistance to checkpoint blockade. Previous attempts to inhibit CAFs clinically have not been successful, however, in part due to a lack of understanding of CAF heterogeneity and function, with some fibroblast popula-tions potentially being tumour suppressive. Recent single-cell transcriptomic studies have advanced our under-standing of fibroblast phenotypes in normal tissues and cancers, allowing for a more precise characterisation of CAF subsets and providing opportunities to develop new therapies. Here we review recent advances in the field, focusing on the evolving area of therapeutic CAF targeting.(c) 2022 Elsevier Inc. All rights reserved.