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  • American Association for Cancer Research (AACR)  (4)
  • 2015-2019  (4)
  • 1
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 77, No. 2_Supplement ( 2017-01-15), p. A05-A05
    Abstract: Introduction: Tumor dimensionality creates a dynamic three dimensional (3D) architecture that is influenced by the associated microenvironment, including stromal cells and the extracellular matrix. These paracrine interactions impact therapeutic efficacy and can alter drug response in vivo , yet most current in vitro models do not accurately recapitulate the dimensionality or the stromal microenvironment of human tumors. In vitro models that are more recapitulative of the human tumor microenvironment have broad applicability in evaluation of signaling pathways driving cancer progression, therapeutic efficacy, and mechanisms involved in therapeutic resistance and tumor recurrence. There is a great need to adapt traditional analytical methods, developed for two dimensional cell culture, for use in 3D tissue models. Herein, a novel perfusion bioreactor system is used to support the multi-week growth and development of 3D breast carcinoma tissue surrogates (measuring 1.0 cm in maximum dimension) consisting of breast carcinoma epithelial cell lines and cancer associated fibroblasts (CAF) in a supportive extracellular matrix. Further, non-invasive imaging techniques, commonly employed to evaluate in vivo animal model systems, were used to measure growth of the surrogates overtime. Methods: 3D breast carcinoma surrogates were generated by incorporating MDA-MB-231 cells (tagged with GFP and luciferase) or MCF-7 cells (tagged with GFP and luciferase), with or without CAF, into an extracellular matrix. Surrogates were cultured in a perfusion bioreactor system for up to 3 weeks. Cell growth was measured on histologic sections of surrogates by counting the number of nucleated cells per surrogate cross-sectional area (cell density). Growth and viability were also determined in the same surrogates over time by using non-invasive fluorescence and luminescence imaging (IVIS 100 system). Results: The use of a flow perfusion bioreactor system resulted in a marked increase in the cell density of surrogates compared to non-perfused surrogates (perfused: 93.3 nucleated cells/area vs. non-perfused: 32.1 nucleated cells/area) at 21 days culture. Fluorescence and luminescence imaging of surrogates, containing increasing concentrations of breast cancer epithelial cells, were imaged at day 0 to confirm a correlation between signal intensity and cell number using each imaging modality (GFP: R2=0.97, p & lt;0.01, Luciferase: R2=0.99, p=0.053 ). Next, fluorescence imaging of the same 3D breast carcinoma surrogates (containing breast carcinoma cells and CAF) overtime was completed at days 0, 7, and 14 of culture and showed an increase in signal (7.9 fold higher signal at day 14 compared to day 0) indicating growth throughout culture. Similar results were seen with imaging of the luciferase signal where the signal was 28.2 fold higher at day 14 compared to day 0. Conclusions: The presence of perfusion allows the growth and development of a recapitulative breast carcinoma surrogate with a size similar to human breast carcinomas at the time of detection and with an appropriate tumor microenvironment. Non-invasive imaging methods have successfully been adapted to evaluate growth of the breast carcinoma surrogates throughout multi-week culture. Future Directions: The use of these perfused breast carcinoma surrogates and imaging modalities in the evaluation of established and candidate cancer therapeutics will be assessed. Citation Format: Kayla F. Goliwas, Jillian R. Richter, Lauren E. Marshall, Joel L. Berry, Andra R. Frost. Evaluation of in vitro three dimensional breast cancer surrogates using histologic morphology and non-invasive imaging to monitor growth and viability throughout culture. [abstract]. In: Proceedings of the AACR Special Conference on Engineering and Physical Sciences in Oncology; 2016 Jun 25-28; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2017;77(2 Suppl):Abstract nr A05.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2017
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  • 2
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 75, No. 15_Supplement ( 2015-08-01), p. LB-226-LB-226
    Abstract: Introduction: The kynurenine pathway is of key importance for immune suppression in cancer, a function exerted primarily via kynurenine as an AhR ligand that potently impairs adaptive immune responses. Inhibition of kynurenine (Kyn) synthesis, mediated by IDO1, TDO (and possibly IDO2) is of great interest for cancer immune checkpoint inhibition, with 3-4 IDO1 inhibitors currently in clinical development. However: (1) IDO1 inhibition has marginal anti-cancer effects as a monotherapy; (2) IDO1 inhibitors only block one of the two major pathways for Kynureine synthesis (the other being via TDO) and (3) IDO1 inhibition does generally not impact the serum concentration of Kynurenine and thus no pharmacodynamic marker is available. Experimental: We postulated that administration of a therapeutic enzyme (Kynureninase) that can degrade Kyn into non-toxic and immunologically inactive metabolites (Alanine and anthranilic acid) may be able to: (a) potently relieve cancer immune suppression. An extensive protein engineering campaign was carried out to develop a Kynureninase suitable for therapeutic administration which was then PEGylated (Kynase-PEG) to enable long circulation persistence. Kynase-PEG was evaluated in the well-established B16-OVA melanoma model in wild type C57BL/6J mice as a monotherapy and in combination with anti-PD-1 administration. Quantitation of tumor size/regression, histology, as well as flow cytometric analyses assessing lymphocytes in the spleen, tumor (TILs) and tumor-draining lymph nodes (dLNs) was used to evaluate efficacy. Summary: Administration of KYNase-PEG in B16-OVA melanoma allografts in C57BL/6J mice reduced serum Kyn levels and resulted in significant tumor growth retardation and extended survival in a manner indistinguishable from that observed with immune checkpoint inhibitors anti-PD1 (clone RMP1-14) or anti-CTLA-4 (clone 9D9) antibodies. KYNase-PEG administration did not display anti-tumor activity in NOD-scid Il2Rγ-/- mice or in IDO1-/- mice revealing that the function of the enzyme is dependent on adaptive immune responses and also on the function of stromal IDO1. Consistent with the hypothesis that depletion of Kyn relieves immune inhibition, we observed a marked increase in CD8+ TILs expressing Gzm B + IFNγ, enhanced proliferation of CD4+ and CD8+ T cells in the tumor dLNs as well as changes in tumor neovascularization. Importantly, combination of KYNase-PEG and anti-PD-1 administration resulted in complete tumor eradication in 60% of the animals (n = 10 per group) for & gt;100 days, with all the surviving animals completely rejecting tumors following re-challenge. For comparison, anti-PD-1 treatment alone, only led to 20% long-term survival in this model. Conclusions: We demonstrated that unlike IDO1 inhibitors, KYNase-PEG displays a significant anti-tumor efficacy as a monotherapy as well as excellent synergism with anti-PD1. The observed increase in tumor infiltration and proliferation of cytotoxic CD8+ T cells argues that the mechanism of action of Kynase-PEG acts by relieving the immune suppression that normally occurs in the tumor microenvironment as a consequence of Kyn accumulation. Thus, KYNase-PEG represent a “first in class” immune checkpoint enzyme. Progress in developing a clinical candidate enzyme will be discussed. Citation Format: Everett Stone, Nicholas Marshall, Moses Donkor, Kendra Triplett, John Blazek, Todd Triplett, Lauren Ehrlich, George Georgiou. Depletion of kynurenine using an engineered therapeutic enzyme potently inhibits cancer immune checkpoints both as a monotherapy and in combination with anti-PD-1. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-226. doi:10.1158/1538-7445.AM2015-LB-226
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2015
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  • 3
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2015
    In:  Cancer Research Vol. 75, No. 15_Supplement ( 2015-08-01), p. 331-331
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 75, No. 15_Supplement ( 2015-08-01), p. 331-331
    Abstract: Background: Breast carcinomas are complex, three-dimensional (3D) tissues composed of breast cancer epithelial cells and stromal components, including fibroblasts and extracellular matrix (ECM). Most in vitro models of carcinoma consist only of cancer epithelial cells, omitting the stroma and, therefore, the 3D architecture of a tumor in vivo. While more accurate 3D modeling allows for enhanced recapitulation of tumor biology and behavior, 3D culture is acknowledged to be challenging with cell viability decreasing dramatically overtime due to lack of available nutrients. Here-in, a novel perfusion bioreactor system supplies medium through 400 uM-diameter channels to maintain survival of a 3D breast cancer surrogate consisting of MDA-MB-231 (231) breast cancer epithelial cells, breast cancer fibroblasts (CAF) and ECM. For optimization of ECM in the breast cancer surrogates, collagen I concentration and species were varied and the effect on 3D morphology and cell viability was assessed. Methods: To assess the effect of collagen concentration on 3D morphology and cell viability, 231 cells and CAF (2:1 ratio) were incorporated into 1.9, 4, 6, or 8 mg/ml (bovine or rat tail) collagen I mixed with 10% basement membrane (BM, i.e. GFR Matrigel) and cultured for 7 days in 8-well chamber slides (non-perfused, solid 3D cultures). H & E stained histologic sections were prepared after fixation and paraffin embedding of the cultures. Cell aggregation, as a measure of 3D morphology, and viability were assessed on histologic sections by image analysis (ImageJ) and autofluorescence, respectively. To compare cell viability in solid 3D culture to surrogates in the perfusion bioreactor system, 231 cells and CAF (2:1 ratio) were incorporated into an ECM composed of 6 mg/ml bovine collagen I mixed with 10% BM and grown in solid 3D culture or in the bioreactor system. The conditions were compared at 7, 14, and 21 days. Results: Collagen I concentration and species had no significant effect on the extent of cell aggregation. However, cell viability was significantly greater in 6 and 8 mg/ml (69.6% and 67.0% alive, respectively) than 1.9 mg/ml (31.9% alive) bovine collagen (ANOVA, p≤0.05). A similar increase in viability with increasing concentration was not seen with rat-tail collagen. Therefore, 6 mg/ml bovine collagen I was used in cancer surrogates in the perfusion bioreactor system. Cell viability was increased in the perfused surrogate (87.9% alive) in comparison to solid cultures (69.6% alive, t-Test, p = 0.03) at 7 days. There was no significant decrease in viability at 14 and 21 days in perfused surrogates (93.8% and 76.7% alive, respectively). Conclusions: Bovine collagen I concentration affects viability of breast cancer cells in 3D. The perfusion bioreactor system promotes cell viability allowing for multi-week culture of breast carcinoma surrogates. Citation Format: Kayla F. Goliwas, Lauren E. Marshall, Kun Yuan, Joel L. Berry, Andra R. Frost. A novel perfusion bioreactor system maintains long-term viability of a three dimensional in vitro breast carcinoma surrogate. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 331. doi:10.1158/1538-7445.AM2015-331
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2015
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  • 4
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 76, No. 14_Supplement ( 2016-07-15), p. 4112-4112
    Abstract: Introduction: Tumor resident mesenchymal stem cells (MSCs) promote cancer progression. Pathways involved in recruitment of MSCs to breast tumor cells remain largely undefined. We aimed at defining the mechanism whereby geminin overexpressing breast tumor cells recruit and interact with MSCs to increase their own aggressiveness. Experimental Procedures: We used co-culturing assay, immunohistochemistry, in vitro invasion assay with or without cytokines neutralization, western blot analysis, immunoprecipitation, immunofluorescence, ELISA, exposure to hypoxic conditions, cytokines receptor inactivation, in vivo orthotopic tumor formation assay in the presence or absence of inhibitors to the proposed signaling pathways, analysis of publically available data sets for the association of selected factors with overall survival, distant metastasis free survival and recurrent free survival to define the mechanism geminin overexpressing cells employ in vivo to recruit and initiate bi-directional interactions with MSCs in order to enhance their own aggressiveness. Results: Here we show that geminin-dependent acetylation of chromatin HMGB1 (Ac-HMGB1) leads to its release to the extracellular space. Extracellular Ac-HMGB1 promotes geminin overexpressing (GemOE) cells survival by binding to RAGE receptors. Extracellular Ac-HMGB1 also triggers expression and activation of RAGE in the non-expressing MSCs leading to induction of CXCR4 expression and migration of MSCs towards SDF1/CXCL12-expressing GemOE cells. Inhibiting c-Abl, RAGE or CXCR4 prevented MSCs recruitment to GemOE cells in vitro and in vivo. Reciprocal interactions between GemOE cells and MSCs elevate the TIC, basal and EMT traits in GemOE cells leading to enhanced aggressiveness. Indeed, faster, larger and more aggressive tumors develop when GemOE cells are co-injected with MSCs in orthotropic tumor model. Concurrently, inhibiting c-Abl and thus geminin function or RAGE or CXCR4 activity in the in vivo model not only suppressed MSCs recruitment to the orthotopic breast tumors, but also led to decrease in TIC, basal and EMT phenotypes in these tumors. Conclusion: We suggest that GemOE generates metastatic tumors in part through recruiting and interacting with MSCs. Citation Format: Theresa Bonner, Suryatheja Ananthula, Janene Nordan, Simran Batth, Gailen D. Marshall, Lauren H. Gardner, Yoshiko Shimizu, Wael M. ElShamy. Geminin overexpression-dependent recruitment and crosstalk with mesenchymal stem cells enhances aggressiveness in triple-negative breast cancers. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4112.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2016
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    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
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