CD26+ fibroblasts are responsible for the fibrosis of scar formation after cutaneous wound healing [49], and evidence supporting a similar fibrotic function of CD26+ CAFs in breast cancer was recently presented in the context of capsular contracture in implant-based reconstructive surgery, demonstrating that CD26+ fibroblasts sorted from human breast capsules produce more collagen-1a1 and have a higher expression of fibrogenic genes than sorted CD26- fibroblasts [50]. The gene discussed is DPP4; the disease is breast cancer.