Two opposing sub-populations of fibroblasts decide progression of pancreatic cancer.

Fibroblasts are a major non-neoplastic component of solid tumors, yet it is unclear whether they promote or oppose cancer. In this issue of Cancer Cell, Hutton et al. report two distinct fibroblast subpopulations that are defined by a single marker, one subpopulation that is tumor permissive and the other that is tumor suppressive and supports anti-tumor immunity.