PDGFRB and neoplasm: When phosphorylated, PDGFR-β contributes to increased IFP by enhanced stimulation of stromal growth, which disrupts interstitial homeostasis (Heuchel et al, 1999; Ostman, 2004) and by participation in tumour angiogenesis (Pietras et al, 2001; Labrecque et al, 2005).