Breast cancer growth and progression require complex interactions between tumor cells and their surrounding environment. Understanding the key tumor-stromal interactions that drive breast cancer growth and metastasis is critical for the development of strategies to inhibit tumor progression and recurrence. Breast cancers are often associated with an inflammatory environment, which has been linked to enhanced breast cancer progression. The availability of anti-inflammatory agents for clinical use enhances the feasibility of targeting the inflammatory microenvironment. However, understanding the mechanisms that drive the formation of an inflammatory environment and identifying key mediators that contribute to breast cancer growth and progression are critical for developing successful anti-inflammatory therapeutic strategies. Fibroblast growth factors (FGFs) are well-established promoters of cancer growth and progression. Collectively, FGFs and their receptors (FGFRs) are overexpressed and/or amplified in up to 75% of human breast cancers and increased FGFR activity is correlated with poor patient outcome. We have recently found that FGFR activation leads to pro-tumorigenic alterations within the extracellular matrix (ECM) including enhanced synthesis and fragmentation of the ECM component hyaluronan. Furthermore, we have identified a novel pathway activated by hyaluronan in breast cancer cells along with pro-inflammatory mediators that contribute to hyaluronan function. These studies have led to the hypothesis that activation of FGFR in breast cancer cells leads to the formation of an HA-rich inflammatory microenvironment, which promotes tumor growth and progression by activating pro-inflammatory signaling pathways and promoting expression of inflammatory mediators. The following specific aims are proposed: 1) Determine the functional contributions of FGFR-mediated HA synthesis and fragmentation to mammary tumor progression. 2) Delineate the specific signaling pathway through which HA regulates inflammatory gene expression in breast cancer cells. 3) Develop combination therapies that target FGFR and downstream HA effectors. The significance of these studies is that they will define novel interactions between tumor cells and the ECM. A major goal of these studies is to determine the ability of combination therapies that target both tumor cells and HA: receptor interactions in the microenvironment to limit tumor initiation and growth.

Public Health Relevance

The proposed studies focus on delineating the mechanisms through which fibroblast growth factor receptor signaling impacts the tumor microenvironment during breast cancer growth and progression. This research is relevant to human health because understanding the mechanisms underlying the promotion of human breast cancer will ultimately lead to the development of novel therapeutic strategies that will improve patient outcome by enhancing initial therapeutic responsiveness, preventing resistance and reducing relapse.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
1R01CA215052-01
Application #
9286463
Study Section
Tumor Microenvironment Study Section (TME)
Program Officer
Hildesheim, Jeffrey
Project Start
2017-04-01
Project End
2022-03-31
Budget Start
2017-04-01
Budget End
2018-03-31
Support Year
1
Fiscal Year
2017
Total Cost
$349,416
Indirect Cost
$120,666
Name
University of Minnesota Twin Cities
Department
Pathology
Type
Schools of Medicine
DUNS #
555917996
City
Minneapolis
State
MN
Country
United States
Zip Code
55455
Nelson, Andrew C; Machado, Heather L; Schwertfeger, Kathryn L (2018) Breaking through to the Other Side: Microenvironment Contributions to DCIS Initiation and Progression. J Mammary Gland Biol Neoplasia 23:207-221
Doak, Geneva R; Schwertfeger, Kathryn L; Wood, David K (2018) Distant Relations: Macrophage Functions in the Metastatic Niche. Trends Cancer 4:445-459
Aukes, Kelly; Forsman, Cynthia; Brady, Nicholas J et al. (2017) Breast cancer cell-derived fibroblast growth factors enhance osteoclast activity and contribute to the formation of metastatic lesions. PLoS One 12:e0185736