Skeletal metastasis is a final and inevitable consequence of advanced prostate cancer. Previous studies aimed to improve understanding of cancer and bone focused primarily on interactions of tumor cells and bone cells. Other critical cellular interactions have been understudied. Myeloid cells play intriguing roles infiltrating tumor tissue and promoting tumor growth; however little is known of the mechanisms of action of myeloid cells in the bone marrow relative to tumor occupation in bone. Tumor cells inevitably encounter these cells during their trajectory from the primary lesion, during dormancy, and in the frank metastatic lesion. Most of the interest in myeloid cells in cancer has centered on the cytokines they produce and/or immune reactions that they orchestrate. Macrophages mediate a specialized process of apoptotic cell phagocytosis termed efferocytosis. The distinct signaling pathways that macrophages use to identify apoptotic cells for efferocytosis are emerging as therapeutic targets for autoimmune conditions and atherosclerosis. Preliminary investigations from the project laboratory demonstrate that macrophage efferocytosis induces polarization towards M2-type tumor- promoting cells with activation of the Stat3-RelA signaling axis. Furthermore, M2-type macrophage depletion with a novel therapeutic, significantly reduces experimental tumor progression in the bone microenvironment. This proposal sets a goal to delineate pathways relative to prostate cancer cell apoptosis and tumor growth during skeletal metastasis using in vitro strategies, novel animal models, as well as human cells and tissues to validate the translation and clinical potential for targeted therapies. The overall hypothesis is that bone marrow macrophages support prostate cancer growth in bone via phagocytosis/efferocytosis of apoptotic tumor cells.
Three aims will address the intriguing question as to how myeloid/macrophage cells drive tumor establishment in the bone marrow. The first will identify the phagocytic/efferocytotic macrophage in the tumor microenvironment of skeletal metastases and determine its ability to support tumor growth. The second will determine the mechanisms of action of milk fat globule EGF-8 (MFGE8), a mediator of efferocytosis, in supporting tumor growth.
The third aim will elucidate targetable mechanisms of macrophage efferocytosis and prostate cancer tumor progression using strategies that directly translate to clinical therapeutic potential

Public Health Relevance

Skeletal metastasis is a challenging consequence of advanced prostate cancer. The central hypothesis of this proposal is that specialized bone marrow cells called macrophages support prostate cancer growth by recapitulating a process they normally use to clear away dead and dying cells. Approaches designed to thwart these mechanisms have therapeutic potential and will be evaluated to better position the field with innovative strategies to combat prostate cancer metastasis. Particularly relevant will be the investigations with a drug called Trabectedin (approved for use in Europe but not yet in the US for osteosarcoma). Trabectedin targets phagocytic macrophages in experimental models of skeletal metastasis, and will set the stage for its clinical application to treat patients with metastatic prostate cancer.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Program Projects (P01)
Project #
5P01CA093900-13
Application #
9312753
Study Section
Special Emphasis Panel (ZCA1-RPRB-J)
Project Start
2004-06-05
Project End
Budget Start
2017-06-01
Budget End
2018-05-31
Support Year
13
Fiscal Year
2017
Total Cost
$246,260
Indirect Cost
$52,911
Name
University of Michigan Ann Arbor
Department
Type
Domestic Higher Education
DUNS #
073133571
City
Ann Arbor
State
MI
Country
United States
Zip Code
48109
Chalfin, Heather J; Glavaris, Stephanie A; Malihi, Paymaneh D et al. (2018) Prostate Cancer Disseminated Tumor Cells are Rarely Detected in the Bone Marrow of Patients with Localized Disease Undergoing Radical Prostatectomy across Multiple Rare Cell Detection Platforms. J Urol 199:1494-1501
Axelrod, Haley D; Pienta, Kenneth J; Valkenburg, Kenneth C (2018) Optimization of Immunofluorescent Detection of Bone Marrow Disseminated Tumor Cells. Biol Proced Online 20:13
Jung, Younghun; Cackowski, Frank C; Yumoto, Kenji et al. (2018) CXCL12? Promotes Metastatic Castration-Resistant Prostate Cancer by Inducing Cancer Stem Cell and Neuroendocrine Phenotypes. Cancer Res 78:2026-2039
Decker, A M; Taichman, L S; D'Silva, N J et al. (2018) Periodontal Treatment in Cancer Patients: An Interdisciplinary Approach. Curr Oral Health Rep 5:7-12
Miller, Dannah R; Tzeng, Cherng-Chyi; Farmer, Trey et al. (2018) Novel CIL-102 derivatives as potential therapeutic agents for docetaxel-resistant prostate cancer. Cancer Lett 436:96-108
Machioka, Kazuaki; Izumi, Kouji; Kadono, Yoshifumi et al. (2018) Establishment and characterization of two cabazitaxel-resistant prostate cancer cell lines. Oncotarget 9:16185-16196
Hill, Elliott E; Kim, Jin Koo; Jung, Younghun et al. (2018) Integrin alpha V beta 3 targeted dendrimer-rapamycin conjugate reduces fibroblast-mediated prostate tumor progression and metastasis. J Cell Biochem 119:8074-8083
Axelrod, Haley D; Valkenburg, Kenneth C; Amend, Sarah R et al. (2018) AXL Is a Putative Tumor Suppressor and Dormancy Regulator in Prostate Cancer. Mol Cancer Res :
de Groot, Amber E; Pienta, Kenneth J (2018) Epigenetic control of macrophage polarization: implications for targeting tumor-associated macrophages. Oncotarget 9:20908-20927
Roca, Hernan; Jones, Jacqueline D; Purica, Marta C et al. (2018) Apoptosis-induced CXCL5 accelerates inflammation and growth of prostate tumor metastases in bone. J Clin Invest 128:248-266

Showing the most recent 10 out of 228 publications