Abstract 2641: The presence of Cyclooxygenase 2, tumor-associated macrophages, and collagen features as prognostic markers for invasive breast carcinoma patients

Inflammation and the organization of collagen in the breast tumor microenvironment is an important mediator of tumor progression. The objective of this study was to assess whether the tissue localization of COX-2 and tumor-associated macrophages were associated with clinicopathological features of invasive carcinoma, including collagen deposition and patient survival outcome. A tumor microarray (TMA) of 371 biopsy specimens from patients with invasive breast carcinoma was analyzed for expression levels of COX-2, the macrophage marker CD68 and activated macrophage marker CD163 in either the tumor nest (TN) or the tumor-associated stroma (TS). The TMA cohort included females; age 18 to 80, with a median follow up of 8.4 years. Biomarkers were correlated against clinicopathological and collagen features. Additionally, survival curves were calculated according to the Kaplan-Meier method. We found that high expression of COX-2 was associated with tumor size (P = 0.006), grade (P < 0.0001), proliferation (P < 0.0001), ER+ (P = 0.001), collagen deposition (P < 0.0001) and density (P = 0.001). One possible mechanism for this, is COX-2 dependent recruitment of macrophages to the tumor microenvironment. This is supported by our finding of high infiltration of both macrophage markers that were associated with tumor size and proliferation; however, only high levels of stromal CD163 were associated with collagen deposition. In order to better analyze patient survival data, samples were divided into quartiles based on their levels of COX-2 expression and/or macrophage infiltration. COX-2 localization in the TN (P = 0.016, HR = 1.71), perpendicular alignment of collagen to the tumor boundary (TACS-3) (P = 0.049, HR = 1.65) and macrophage recruitment were predictors of poor overall survival (OS). Furthermore, patient survival was worsened if patients had a high CD163 macrophage infiltration (TN: P < 0.0001, HR = 2.86; TS: P = 0.002, HR = 2.54). This notion is further established by the finding of our multivariate analysis that high numbers of CD163+ macrophages in the TS as an independent prognostic factor (P = 0.001, HR = 2.90). These results suggest that in invasive carcinoma the localization of inflammatory markers within the tumor are biomarkers for patient survival outcome. Therefore, we propose that these patients may benefit from a selective COX-2 inhibitor and/or immune modulation therapies.

Citation Format: Karla Esbona, Yanyao Yi, Menggang Yu, Rachel Van Doorn, Matthew Conklin, Douglas Graham, Kari Wisinski, Suzanne Ponik, Kevin Eliceiri, Lee Wilke, Patricia Keely. The presence of Cyclooxygenase 2, tumor-associated macrophages, and collagen features as prognostic markers for invasive breast carcinoma patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2641.

Abstract PR15: Haptotaxis and direct remodeling of the extracellular matrix by tumor cells is important for metastasis

The tissue microenvironment, composed of stromal cells and extracellular matrix (ECM), is known to contribute to tumor progression, by providing both the structure and signals that promote tumor cell proliferation, survival and invasion. Fibronectin and collagen are major components of the tumor microenvironment, however, how tumor cells gain the ability to respond to these substrate-bound cues and how ECM sensing contributes to promoting metastasis remain poorly understood. Here, using a combination of in vitro and in vivo imaging, we show that gradients of FN can promote directional cell motility of breast cancer cells, a process dependent upon the actin regulatory Mena. Expression of the pro-metastatic isoform MenaINV allows cells to haptotax towards very high concentrations of FN, found near blood vessels and tumor periphery. Haptotaxis requires the direct interaction between α5β1 integrin and Mena/ MenaINV and is driven by outside-in signaling at focal complexes, crosstalk between α5β1 and EGFR, and inside-out tumor cell dependent ECM remodeling. These findings are clinically relevant as patients with high levels of MenaINV protein and FN have increased recurrence and decreased survival in two breast cancer cohorts. Our results identify a novel tumor cell-intrinsic mechanism that promotes ECM remodeling and directed migration, ultimately affecting metastasis.

Citation Format: Madeleine J. Oudin, Oliver Jonas, Tatiana Kosciuk, Liliane Broye, Jeff Wyckoff, Joelle Klazen, John Lamar, Sreeja Asokan, Charlie Whittaker, Robert Langer, Michael Cima, Kari Wisinski, Richard Hynes, Douglas Lauffenburger, Patricia Keely, James Bear, Frank Gertler. Haptotaxis and direct remodeling of the extracellular matrix by tumor cells is important for metastasis. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Metastasis; 2015 Nov 30-Dec 3; Austin, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(7 Suppl):Abstract nr PR15.

Abstract B41: Haptotaxis and direct remodeling of the extracellular matrix by tumor cells is important for metastasis

This abstract is being presented as a short talk in the scientific program. A full abstract is printed in the Proffered Abstracts section (PR15) of the Conference Proceedings.

Citation Format: Madeleine J. Oudin, Oliver Jonas, Tatiana Kosciuk, Liliane Broye, Jeff Wyckoff, Joelle Klazen, John Lamar, Sreeja Asokan, Charlie Whittaker, Robert Langer, Michael Cima, Kari Wisinski, Richard Hynes, Douglas Lauffenburger, Patricia Keely, James Bear, Frank Gertler. Haptotaxis and direct remodeling of the extracellular matrix by tumor cells is important for metastasis. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Metastasis; 2015 Nov 30-Dec 3; Austin, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(7 Suppl):Abstract nr B41.

COX-2 modulates mammary tumor progression in response to collagen density

Background

High breast density is linked to an increased risk of breast cancer, and correlates with changes in collagen. In a mouse model of mammary carcinoma in the context of increased collagen deposition, the MMTV-PyMT/Col1a1^tm1jae, there is accelerated mammary tumor formation and progression. Previous gene expression analysis suggests that increased collagen density elevates expression of PTGS2 (prostaglandin-endoperoxide synthase 2), the gene for cyclooxygenase-2 (COX-2).

Methods

To understand the role of COX-2 in tumor progression within a collagen-dense microenvironment, we treated MMTV-PyMT or MMTV-PyMT/Col1a1^tm1jae tumors prior to and after tumor formation. Animals received treatment with celecoxib, a specific COX-2 inhibitor, or placebo. Mammary tumors were examined for COX-2, inflammatory and stromal cell components, and collagen deposition through immunohistochemical analysis, immunofluorescence, multiplex cytokine ELISA and tissue imaging techniques.

Results

PyMT/Col1a1^tm1jae tumors were larger, more proliferative, and expressed higher levels of COX-2 and PGE2 than PyMT tumors in wild type (WT) mice. Treatment with celecoxib significantly decreased the induced tumor size and metastasis of the PyMT/Col1a1 tumors, such that their size was not different from the smaller PyMT tumors. Celecoxib had minimal effect on the PyMT tumors. Celecoxib decreased expression levels of COX-2, PGE2, and Ki-67. Several cytokines were over-expressed in PyMT/Col1a1 compared to PyMT, and celecoxib treatment prevented their over-expression. Furthermore, macrophage and neutrophil recruitment were enhanced in PyMT/Col1a1 tumors, and this effect was inhibited by celecoxib. Notably, COX-2 inhibition reduced overall collagen deposition. Finally, when celecoxib was used prior to tumor formation, PyMT/Col1a1 tumors were fewer and smaller than in untreated animals.

Conclusion

These findings suggest that COX-2 has a direct role in modulating tumor progression in tumors arising within collagen-dense microenvironments, and suggest that COX-2 may be an effective therapeutic target for women with dense breast tissue and early-stage breast cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-016-0695-3) contains supplementary material, which is available to authorized users.

Capturing relevant extracellular matrices for investigating cell migration

Much progress in understanding cell migration has been determined by using classic two-dimensional (2D) tissue culture platforms. However, increasingly, it is appreciated that certain properties of cell migration in vivo are not represented by strictly 2D assays. There is much interest in creating relevant three-dimensional (3D) culture environments and engineered platforms to better represent features of the extracellular matrix and stromal microenvironment that are not captured in 2D platforms. Important to this goal is a solid understanding of the features of the extracellular matrix—composition, stiffness, topography, and alignment—in different tissues and disease states and the development of means to capture these features

Abstract B02: Matrix stiffness regulates local metabolism of breast carcinoma cells

Dense breast tissue is one of the single largest risk factors for the development of breast cancer, and one of the primary proteins responsible for increased breast density is the core extracellular matrix (ECM) component, collagen. Similar to other ECM proteins, collagen plays a structural role underlying tissue organization and increased collagen deposition correlates to a stiffer ECM and cellular microenvironment. Interestingly, changes to the stiffness of the ECM or microenvironment have profound and poorly-understood effects on cell migration, cell proliferation, and cancer progression. Consistent with an expanding role of ECM stiffness in cell signaling, we report that increased matrix stiffness also affects cellular metabolism and respiration. Using specific pharmacological inhibitors and quantitative imaging modalities like fluorescence lifetime microscopy, we are able to show that changes in collagen stiffness can cause a metabolic shift towards a more glycolytic, Warburg-like equilibrium in breast carcinoma cells. Matrix stiffness regulates the expression of several metabolic enzymes, including PDHK-1, which is poised to regulate this shift.

Note: This abstract was not presented at the conference.

Citation Format: Brian Burkel, Suzanne Ponik, Brett Morris, Kevin Eliceiri, Patricia Keely. Matrix stiffness regulates local metabolism of breast carcinoma cells. [abstract]. In: Abstracts: AACR Special Conference on Cellular Heterogeneity in the Tumor Microenvironment; 2014 Feb 26-Mar 1; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2015;75(1 Suppl):Abstract nr B02. doi:10.1158/1538-7445.CHTME14-B02

Abstract A082: Study of the effects of localized collagen manipulation on the behavior of breast cancer cells

The tumor microenvironment is complex and heterogeneous, comprised of the extracellular matrix, various cell types, blood vessels, and soluble factors. Multiple interactions occur between tumor cells and their environment which affect cellular behavior and the composition of the tumor microenvironment. Changes to the composition of collagen within the tumor microenvironment have been linked to an increased risk of developing breast carcinoma and an increased invasiveness of breast cancer cells. The goal of this study is to understand how selected, well-controlled manipulations of the collagen composition alter the behavior of an invasive human breast cancer cell line, MDA-MB-231. A BioMEMS device will be loaded with molecules that alter collagen and inserted into a 3-D gel containing MDA-MB-231 cells, to establish a localized gradient of these molecules. The compositional changes include increased collagen concentration through stimulating cellular deposition of collagen, increased collagen crosslinking and inhibition of a collagen cross-linker produced by tumor cells. Confocal reflectance microscopy, atomic force microscopy, and environmental scanning electron microscopy are utilized to characterize the changes induced and the rates at which the changes occur. Changes in gene expression are investigated to determine the pathways each of the collagen manipulations induce which result in the observed changes to cellular behavior. The observed alterations in cellular phenotype resulting from these collagen changes will help to better understand what degree of changes occur within breast carcinoma resulting in cancer progression.

Citation Format: Ashley N. Clark, James Williams, Michael Padgen, Patricia Keely, James Castracane. Study of the effects of localized collagen manipulation on the behavior of breast cancer cells. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Breast Cancer Research: Genetics, Biology, and Clinical Applications; Oct 3-6, 2013; San Diego, CA. Philadelphia (PA): AACR; Mol Cancer Res 2013;11(10 Suppl):Abstract nr A082.

Mammographic density: intersection of science, the law, and clinical practice

High mammographic density is associated with a two- to sixfold increased risk of breast cancer. Mammographic density can be altered by endogenous and exogenous hormonal factors and generally declines with age. Mammographic density is affected by confounding factors such as age, parity, menopausal status, and body mass index (BMI), thus making interpretation of mammographic density challenging. None of the established means of measuring mammographic density are entirely satisfactory because they are time consuming and/or subjective. Although mammographic density has been shown to predict breast cancer risk, the role of mammographic density in precisely assessing a woman's breast cancer risk over her lifetime and evaluating response to risk-reduction strategies cannot be fully realized until we have a better understanding of the biology that links mammographic density to breast cancer risk.

Abstract B71: Syndecan-1 promotes breast cancer metastasis by modulating tissue stiffness

Tumor-stroma interactions are integral to breast cancer progression and metastasis. It has been well established that women with dense breast tissue have increased risk of developing breast cancer as compared to women with less dense breast tissue; it has also been documented that a stiffer extracellular matrix (ECM) can promote tumor cell invasion both in vitro and in vivo. Our lab has previously shown that Syndecan-1 (Sdc1), a cell surface heparan sulfate proteoglycan, regulates the in vitro organization of a fibroblast-constructed ECM that thus creates an invasion-permissive microenvironment. Therefore, we sought to characterize the role of stromal Sdc1 in cancer progression in vivo. Using the 4T1 model of late stage metastatic breast cancer in both Sdc1 wild-type (WT) and Sdc1 knock-out (KO) mice, we assayed for tumor metastasis from orthotopic tumor cell implants. Sdc1 deficiency in the host did not influence the primary tumor weight or growth rate, but significantly reduced the incidence and the number of metastatic lesions (p<0.001, p<0.0001, respectively). In an effort to dissect out the mechanism by which loss of stromal Sdc1 is inhibiting metastasis, we analyzed the tumor microenvironment for the presence of specific cell types and structural differences. There was no difference in the recruitment of macrophages, the activation of fibroblasts, angiogenesis, or the structure or deposition of collagen between 4T1-induced tumors in the Sdc1 WT and Sdc1 KO mice. Interestingly, preliminary data suggest the tumors from the Sdc1 WT mice are significantly stiffer than the tumors from Sdc1 KO mice, as measured by atomic force microscopy. To determine whether Sdc1 was influencing later stages of metastasis we injected tumor cells via tail vein to specifically assay extravasation and metastatic outgrowth. After 2 weeks, all mice assayed had metastatic lesions but the Sdc1 WT mice had significantly more numerous and larger lesions (p<0.004, p<0.05, respectively). These data indicate that the presence of stromal Sdc1 promotes tumor cell outgrowth in the metastatic target organ, but may not play as large a role in tumor cell extravasation based on the finding that all mice assayed had metastatic lesions. These results further suggest that Sdc1 influences breast cancer metastasis by promoting increased tissue stiffness, which promotes tumor cell invasion and tumor outgrowth at secondary metastatic target organs, and ultimately promotes formation of metastatic lesions.

Citation Format: Colleen L. Chute, Patricia Keely, Caroline Alexander, Andreas Friedl. Syndecan-1 promotes breast cancer metastasis by modulating tissue stiffness. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Invasion and Metastasis; Jan 20-23, 2013; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2013;73(3 Suppl):Abstract nr B71.

Mammographic density: intersection of science, the law, and clinical practice

High mammographic density is associated with a two- to sixfold increased risk of breast cancer. Mammographic density can be altered by endogenous and exogenous hormonal factors and generally declines with age. Mammographic density is affected by confounding factors such as age, parity, menopausal status, and body mass index (BMI), thus making interpretation of mammographic density challenging. None of the established means of measuring mammographic density are entirely satisfactory because they are time consuming and/or subjective. Although mammographic density has been shown to predict breast cancer risk, the role of mammographic density in precisely assessing a woman's breast cancer risk over her lifetime and evaluating response to risk-reduction strategies cannot be fully realized until we have a better understanding of the biology that links mammographic density to breast cancer risk.

Abstract B61: Postpartum mammary gland involution drives DCIS progression through collagen and COX-2, identifying a target for intervention

Prognosis of young women's breast cancer is influenced by reproductive history. Women diagnosed within five years postpartum have worse prognosis than nulliparous women or women diagnosed during pregnancy. We propose that breast involution following pregnancy accounts for the poor prognosis of breast cancers diagnosed postpartum. Our ‘involution hypothesis’ states that the physiologically normal microenvironment of the postpartum involuting gland is tumor promotional; however, testing the involution hypothesis has been limited by lack of pre-clinical models. We developed a mouse xenograft model of PABC that isolates postpartum mammary gland involution as a driving force for breast cancer progression and metastasis. In this model, human breast cancer cells are injected into actively involuting mouse mammary glands and nulliparous controls. Results from this model indicate that tumor cells exposed to the collagen rich involuting mammary microenvironment form larger tumors characterized by abundant fibrillar collagen, high COX-2 expression, and an invasive phenotype. In culture, these tumor cells are invasive in a collagen/COX-2-dependent manner. Importantly, in the involuting mammary gland, inhibition of COX-2 with celecoxib or ibuprofen reduced the collagen fibrillogenesis associated with involution, as well as tumor growth and lung infiltration. These anti-tumor effects were observed without blocking apoptosis of secretory mammary epithelial cells, which is required to remodel the gland to a non-secretory state, and is a requisite for advancing this strategy to clinical trial. The question of whether an NSAID based intervention study could be aimed at recently pregnant women at high risk for breast cancer remains to be determined, but is an extremely desirable objective given that there are more than 6 million pregnancies in the US per year. In summary, these data support further research to determine whether women at high-risk for postpartum breast cancer would benefit from treatment with NSAIDs during postpartum involution.

This work was funded by DOD, Komen, and ACS.

Citation Information: Cancer Prev Res 2011;4(10 Suppl):B61.

Integrins and GTPases in tumour cell growth, motility and invasion

One of the most exciting aspects of recent research on cell-adhesion receptors is the realization that these molecules can participate in bidirectional signal-transduction processes. Integrins can convey signals from the extracellular matrix to the cell interior, and intracellular events can influence the affinity of integrins for their ligands. Another important emerging concept is that integrins and small GTPases of the Rho family work together to coordinate both cytoskeletal organization and signalling processes. In this review, the authors examine integrin signalling and integrin-GTPase interplay in the context of cancer cell growth and behaviour.