A Subset of Cancer-Associated Fibroblasts Determines Therapy Resistance.

While functional heterogeneity of fibroblastic cells populating the tumor microenvironment is increasingly recognized, lack of definitive markers complicates elucidation of roles among ostensibly distinctive fibroblastic states. In this issue of Cell, Su et al. characterize a new pro-tumorigenic cancer-associated fibroblast subset mediating chemoresistance defined and driven by a novel signaling pathway.