Neoplastic transformation and tumor progression is mediated by intrinsic genetic changes in tumor cells, as well as extrinsic factors such as infiltrating innate inflammatory cells, adaptive immune cells, endothelial cells (EC), the extracellular matrix (ECM) and mesenchymal-derived stromal cells (MDSCs). MDSCs (tumor associated fibroblasts (TAFs) and pericytes) have emerged as important players in tumor initiation, invasive growth and metastasis through their roles in ECM remodeling, angiogenesis and stromagenesis. However, the mechanisms involved are not yet well-defined. The long-term goal of this project is to define such mechanisms. This proposal is focused on the role of a stromal cell-restricted protease, Fibroblast Activation Protein (FAP), in lung cancer. FAP is a well defined marker of TAFs and blood vessel associated pericytes that can be exploited to study the generation and function of these important cell populations. FAP expression is restricted to fibroblasts in tumors, wound healing and fibrosis and is tightly regulated. FAP contains a structurally defined catalytic domain that mediates its protease activities. Our preliminary data establish that FAP+ cells are a prominent component of human lung cancers and that genetic deletion of FAP indirectly inhibits tumor cell proliferation in mouse models. In addition, our results indicate that FAP is a critical determinant of collagen accumulation in tumors. These data provide proof-of-principle that targeting stromal cell-mediated processes may be an effective approach to treating epithelial-derived solid tumors. We now propose to define the mechanistic bases of the tumor promoting activity of FAP in mouse models of lung cancer (Aim 1) and to define the mechanisms that drive the generation of TAFs (Aim2).
In Aim 3, we will test the hypothesis that FAP promotes the growth of human lung tumor cells through mechanisms conserved between mouse and man. The proposed studies will define TAF-dependent mechanisms that promote the growth of lung cancers. However, as FAP-expressing stromal cells are a prominent feature in a wide variety of tumor types, the results of these studies are likely to have broad implications for epithelial-derived tumors. These studies will likely lead to the development of stroma-targeted therapies that are likely to synergize with therapies directed against tumor cells per se.

Public Health Relevance

As the second leading cause of death, cancer presents a major public health problem. Lung cancer is the second most common cancer and the leading cause of cancer deaths. Therefore, there is an urgent need to develop new treatments for lung cancer. We now know that the tumor microenvironment plays a critical role in driving neoplastic transformation and tumor progression. We have obtained evidence that targeting a protease restricted to mesenchymal derived stromal cells, which are prevalent in a wide variety of solid tumors, inhibits tumor growth. The proposed experiments will define the mechanisms that lead to the expression of this protease in tumors and the mechanisms by which it promotes tumor growth. These studies are likely to lead to the clinical development of new anti-tumor therapies that target stromal cells.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
7R01CA141144-05
Application #
8728438
Study Section
Tumor Microenvironment Study Section (TME)
Program Officer
Mohla, Suresh
Project Start
2010-04-01
Project End
2015-01-31
Budget Start
2014-02-01
Budget End
2015-01-31
Support Year
5
Fiscal Year
2014
Total Cost
$276,286
Indirect Cost
$92,294
Name
University of Pennsylvania
Department
Veterinary Sciences
Type
Schools of Veterinary Medicine
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Avery, Diana; Govindaraju, Priya; Jacob, Michele et al. (2018) Extracellular matrix directs phenotypic heterogeneity of activated fibroblasts. Matrix Biol 67:90-106
Govindaraju, Priya; Todd, Leslie; Shetye, Snehal et al. (2018) CD44-dependent inflammation, fibrogenesis, and collagenolysis regulates extracellular matrix remodeling and tensile strength during cutaneous wound healing. Matrix Biol :
Puré, Ellen; Blomberg, Rachel (2018) Pro-tumorigenic roles of fibroblast activation protein in cancer: back to the basics. Oncogene 37:4343-4357
Puré, Ellen; Lo, Albert (2016) Can Targeting Stroma Pave the Way to Enhanced Antitumor Immunity and Immunotherapy of Solid Tumors? Cancer Immunol Res 4:269-78
Fan, Ming-Hui; Zhu, Qiang; Li, Hui-Hua et al. (2016) Fibroblast Activation Protein (FAP) Accelerates Collagen Degradation and Clearance from Lungs in Mice. J Biol Chem 291:8070-89
Newick, Kheng; O'Brien, Shaun; Sun, Jing et al. (2016) Augmentation of CAR T-cell Trafficking and Antitumor Efficacy by Blocking Protein Kinase A Localization. Cancer Immunol Res 4:541-51
Brisson, Becky K; Mauldin, Elizabeth A; Lei, Weiwei et al. (2015) Type III Collagen Directs Stromal Organization and Limits Metastasis in a Murine Model of Breast Cancer. Am J Pathol 185:1471-86
Lo, Albert; Wang, Liang-Chuan S; Scholler, John et al. (2015) Tumor-Promoting Desmoplasia Is Disrupted by Depleting FAP-Expressing Stromal Cells. Cancer Res 75:2800-2810
Wang, Liang-Chuan S; Lo, Albert; Scholler, John et al. (2014) Targeting fibroblast activation protein in tumor stroma with chimeric antigen receptor T cells can inhibit tumor growth and augment host immunity without severe toxicity. Cancer Immunol Res 2:154-66
Moon, Edmund K; Wang, Liang-Chuan; Dolfi, Douglas V et al. (2014) Multifactorial T-cell hypofunction that is reversible can limit the efficacy of chimeric antigen receptor-transduced human T cells in solid tumors. Clin Cancer Res 20:4262-73

Showing the most recent 10 out of 11 publications