title: Tumor-driven paracrine platelet-derived growth factor receptor alpha signaling is a key determinant of stromal cell recruitment in a model of human lung carcinoma.
abstract: Activated fibroblasts are thought to play important roles in the progression of many solid tumors, but little is known about the mechanisms responsible for the recruitment of fibroblasts in tumors. Using several methods, we identified platelet-derived growth factor A (PDGFA) as the major fibroblast chemoattractant and mitogen from conditioned medium generated by the Calu-6 lung carcinoma cell line. In addition, we showed that Calu-6 tumors express significant levels of PDGFC, and that the levels of expression of these two PDGFRalpha ligands correlate strongly with the degree of stromal fibroblast infiltration into the tumor mass. The most intense expression of PDGFRalpha was observed in fibroblasts in the tumor outer rim. We subsequently showed that disrupting PDGFRalpha-mediated signaling results in significant inhibition of tumor growth in vivo. Furthermore, analysis of a compendium of microarray data revealed significant expression of PDGFA, PDGFC, and PDGFRalpha in human lung tumors. We propose that therapies targeting this stromal cell type may be effective in treating certain types of solid tumors.
authors: Department of Molecular Oncology, Pathology, Genentech, Inc., South San Francisco, California 94080, USA.
authors: Max L
authors: ML
authors: Tejada
authors: Lanlan
authors: L
authors: Yu
authors: Jianying
authors: J
authors: Dong
authors: Kenneth
authors: K
authors: Jung
authors: Gloria
authors: G
authors: Meng
authors: Franklin V
authors: FV
authors: Peale
authors: Gretchen D
authors: GD
authors: Frantz
authors: Linda
authors: L
authors: Hall
authors: XiaoHuan
authors: X
authors: Liang
authors: Hans-Peter
authors: HP
authors: Gerber
authors: Napoleone
authors: N
authors: Ferrara