title: Upregulated stromal EGFR and vascular remodeling in mouse xenograft models of angiogenesis inhibitor-resistant human lung adenocarcinoma.
abstract: Angiogenesis is critical for tumor growth and metastasis, and several inhibitors of angiogenesis are currently in clinical use for the treatment of cancer. However, not all patients benefit from antiangiogenic therapy, and those tumors that initially respond to treatment ultimately become resistant. The mechanisms underlying this, and the relative contributions of tumor cells and stroma to resistance, are not completely understood. Here, using species-specific profiling of mouse xenograft models of human lung adenocarcinoma, we have shown that gene expression changes associated with acquired resistance to the VEGF inhibitor bevacizumab occurred predominantly in stromal and not tumor cells. In particular, components of the EGFR and FGFR pathways were upregulated in stroma, but not in tumor cells. Increased activated EGFR was detected on pericytes of xenografts that acquired resistance and on endothelium of tumors with relative primary resistance. Acquired resistance was associated with a pattern of pericyte-covered, normalized revascularization, whereas tortuous, uncovered vessels were observed in relative primary resistance. Importantly, dual targeting of the VEGF and EGFR pathways reduced pericyte coverage and increased progression-free survival. These findings demonstrated that alterations in tumor stromal pathways, including the EGFR and FGFR pathways, are associated with, and may contribute to, resistance to VEGF inhibitors and that targeting these pathways may improve therapeutic efficacy. Understanding stromal signaling may be critical for developing biomarkers for angiogenesis inhibitors and improving combination regimens.
authors: Department of Thoracic/Head and Neck Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA.
authors: Tina
authors: T
authors: Cascone
authors: Matthew H
authors: MH
authors: Herynk
authors: Li
authors: L
authors: Xu
authors: Zhiqiang
authors: Z
authors: Du
authors: Humam
authors: H
authors: Kadara
authors: Monique B
authors: MB
authors: Nilsson
authors: Carol J
authors: CJ
authors: Oborn
authors: Yun-Yong
authors: YY
authors: Park
authors: Baruch
authors: B
authors: Erez
authors: Jörg J
authors: JJ
authors: Jacoby
authors: Ju-Seog
authors: JS
authors: Lee
authors: Heather Y
authors: HY
authors: Lin
authors: Fortunato
authors: F
authors: Ciardiello
authors: Roy S
authors: RS
authors: Herbst
authors: Robert R
authors: RR
authors: Langley
authors: John V
authors: JV
authors: Heymach
mesh_terms: D000230:Adenocarcinoma / Q000098:blood supply* / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D020533:Angiogenesis Inhibitors / Q000494:pharmacology*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D061067:Antibodies, Monoclonal, Humanized; D017209:Apoptosis / Q000187:drug effects; D000068258:Bevacizumab; D045744:Cell Line, Tumor; D019008:Drug Resistance, Neoplasm; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D020869:Gene Expression Profiling; D006801:Humans; D008175:Lung Neoplasms / Q000098:blood supply* / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008819:Mice, Nude; D009389:Neovascularization, Pathologic / Q000188:drug therapy; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012334:RNA, Neoplasm / Q000235:genetics / Q000378:metabolism; D017154:Stromal Cells / Q000378:metabolism; D015854:Up-Regulation; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors / Q000235:genetics; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000037:antagonists & inhibitors / Q000378:metabolism; D023041:Xenograft Model Antitumor Assays
chemical_list: D020533:Angiogenesis Inhibitors; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D012333:RNA, Messenger; D012334:RNA, Neoplasm; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab; D066246:ErbB Receptors; D040301:Vascular Endothelial Growth Factor Receptor-2