Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • American Association for Cancer Research (AACR)  (50)
  • 1
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 83, No. 7_Supplement ( 2023-04-04), p. 5407-5407
    Abstract: Patient-derived xenografts (PDXs) model human intra-tumoral heterogeneity in the context of the intact tissue of immunocompromised mice. Histological imaging via hematoxylin and eosin (H & E) staining is performed on PDX samples for routine assessment and, in principle, captures the complex interplay between tumor and stromal cells. Deep learning (DL)-based analysis of large human H & E image repositories has extracted inter-cellular and morphological signals correlated with disease phenotype and therapeutic response. Here, we present an extensive, pan-cancer repository of nearly 1,000 PDX and paired human progenitor H & E images. These images, curated from the PDXNet consortium, are associated with genomic and transcriptomic data, clinical metadata, pathological assessment of cell composition, and, in several cases, detailed pathological annotation of tumor, stroma, and necrotic regions. We demonstrate that DL can be applied to these images to classify tumor regions with an accuracy of 0.87. Further, we show that DL can predict xenograft-transplant lymphoproliferative disorder, the unintended outgrowth of human lymphocytes at the transplantation site, with an accuracy of 0.97. This repository enables PDX-specific investigations of cancer biology through histopathological analysis and contributes important model system data that expand on existing human histology repositories. We expect the PDXNet Image Repository to be valuable for controlled digital pathology analysis, both for the evaluation of technical issues such as stain normalization and for development of novel computational methods based on spatial behaviors within cancer tissues. Citation Format: Brian S. White, Xing Yi Woo, Soner Koc, Todd Sheridan, Steven B. Neuhauser, Shidan Wang, Yvonne A. Evrard, John David Landua, R Jay Mashl, Sherri R. Davies, Bingliang Fang, Maria Gabriela Raso, Kurt W. Evans, Matthew H. Bailey, Yeqing Chen, Min Xiao, Jill Rubinstein, Ali Foroughi pour, Lacey Elizabeth Dobrolecki, Maihi Fujita, Junya Fujimoto, Guanghua Xiao, Ryan C. Fields, Jacqueline L. Mudd, Xiaowei Xu, Melinda G. Hollingshead, Shahanawaz Jiwani, PDXNet consortium, Tiffany A. Wallace, Jeffrey A. Moscow, James H. Doroshow, Nicholas Mitsiades, Salma Kaochar, Chong-xian Pan, Moon S. Chen, Luis G. Carvajal-Carmona, Alana L. Welm, Bryan E. Welm, Ramaswamy Govindan, Shunqiang Li, Michael A. Davies, Jack A. Roth, Funda Meric-Bernstam, Yang Xie, Meenhard Herlyn, Li Ding, Michael T. Lewis, Carol J. Bolt, Dennis A. Dean, Jeffrey H. Chuang. A pan-cancer PDX histology image repository with genomic and pathological annotations for deep learning analysis. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5407.
    Type of Medium: Online Resource
    ISSN: 1538-7445
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2023
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 82, No. 12_Supplement ( 2022-06-15), p. 1202-1202
    Abstract: Patient-derived xenografts (PDXs) recapitulate intratumoral spatial heterogeneity and simulate a tumor microenvironment in which human immune and stromal cells in the PDX are replaced over passages by murine cells partially lacking immune function. Histological imaging enables exploring the spatial heterogeneity and dynamics of cancer, stromal, and immune cell interactions as correlates of tumor stage and therapeutic response over passages. We created a repository of curated, haematoxylin and eosin (H & E) images as a community resource for addressing these questions. Images were generated at five sites within the NCI’s PDX Development and Trial Centers Research Network (PDXNet) and the NCI Patient-Derived Models Repository. Over 900 images, including 739 from PDXs and 190 from paired patients, are hosted on the Seven Bridges Genomics Cancer Genomics Cloud. They represent 42 cancer subtypes, including breast cancer (n=134), colon adenocarcinoma (COAD; n=94), pancreatic cancer (n=87), lung adenocarcinoma (LUAD; n=80), melanoma (n=71), and squamous cell lung cancer (LUSC; n=65). Paired human/PDX images are available for each of these cancers. Human and/or PDX images generated following patient treatment are available for 37 of the subtypes. Most images are from early passages (P0: 158; P1: 292; P2: 152; P3: 69; & gt;P3: 55). Annotations include sex, age, race, ethnicity, and, for most images, pathological assessment of tissue-level percent cancer, stromal, and necrotic cell content (n=639) and tumor stage (n=650). RNA and exome sequencing data are available for 99 and 228 images, respectively, matched at the patient or sample level. Quality control was performed using HistoQC. Cells were segmented and labeled as neoplastic, necrotic, immune, stromal, or other using Hover-Net and predictions of total neoplastic cell area correlated with whole-slide pathological assessment of cancer cell percentage (COAD: r=0.51; LUSC: r=0.59). HD-Staining, another classification approach, was applied to a subset of images and our clinical annotations will facilitate validation of this and related methods. Features of 512 x 512 pixel tiles were computed using the Inception V3 convolutional neural network pre-trained on ImageNet. Unsupervised clustering of these features demonstrate inter-patient heterogeneity within pathologist-annotated tumor regions. A classifier developed using pathologist-annotated cancer, stromal, and necrotic regions and trained on the features in LUSC images (n=10 images) achieved a cross-validation accuracy of 96% for cancer tiles across (n=5) LUAD images. Accuracy was lower for stromal classification (90%), likely reflecting current limitations of our small, but growing, labeled training set. Our repository of clinically-annotated PDX H & E images should aid the community in studying spatial heterogeneity and in training deep learning-based image analysis methods. Citation Format: Brian S. White, Xingyi Woo, Soner Koc, Todd Sheridan, Steven B. Neuhauser, Akshat M. Savaliya, Lacey E. Dobrolecki, John D. Landua, Matthew H. Bailey, Maihi Fujita, Kurt W. Evans, Bingliang Fang, Junya Fujimoto, Maria Gabriela Raso, Shidan Wang, Guanghua Xiao, Yang Xie, Sherri R. Davies, Ryan C. Fields, R Jay Mashl, Jacqueline L. Mudd, Yeqing Chen, Min Xiao, Xiaowei Xu, Melinda G. Hollingshead, Shahanawaz Jiwani, PDXNet Consortium, Yvonne A. Evrard, Tiffany A. Wallace, Jeffrey A. Moscow, James H. Doroshow, Nicholas Mitsiades, Salma Kaochar, Chong-xian Pan, Moon S. Chen, Luis G. Carvajal-Carmona, Alana L. Welm, Bryan E. Welm, Michael T. Lewis, Ramaswamy Govindan, Li Ding, Shunqiang Li, Meenhard Herlyn, Michael A. Davies, Jack A. Roth, Funda Meric-Bernstam, Carol J. Bult, Brandi Davis-Dusenbery, Dennis A. Dean, Jeffrey H. Chuang. A repository of PDX histology images for exploring spatial heterogeneity and cancer dynamics [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1202.
    Type of Medium: Online Resource
    ISSN: 1538-7445
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2022
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2017
    In:  Cancer Immunology Research Vol. 5, No. 3 ( 2017-03-01), p. 198-210
    In: Cancer Immunology Research, American Association for Cancer Research (AACR), Vol. 5, No. 3 ( 2017-03-01), p. 198-210
    Abstract: Heterogeneity in tumor immune responses is a poorly understood yet critical parameter for successful immunotherapy. In two doxycycline-inducible models where oncogenic H-RasG12V is targeted either to the epidermal basal/stem cell layer with a Keratin14-rtTA transgene (K14Ras), or committed progenitor/suprabasal cells with an Involucrin-tTA transgene (InvRas), we observed strikingly distinct tumor immune responses. On threshold doxycycline levels yielding similar Ras expression, tumor latency, and numbers, tumors from K14Ras mice had an immunosuppressed microenvironment, whereas InvRas tumors had a proinflammatory microenvironment. On a Rag1−/− background, InvRas mice developed fewer and smaller tumors that regressed over time, whereas K14Ras mice developed more tumors with shorter latency than Rag1+/+ controls. Adoptive transfer and depletion studies revealed that B-cell and CD4 T-cell cooperation was critical for tumor yield, lymphocyte polarization, and tumor immune phenotype in Rag1+/+ mice of both models. Coculture of tumor-conditioned B cells with CD4 T cells implicated direct contact for Th1 and regulatory T cell (Treg) polarization, and CD40-CD40L for Th1, Th2, and Treg generation, a response not observed from splenic B cells. Anti-CD40L caused regression of InvRas tumors but enhanced growth in K14Ras, whereas a CD40 agonist mAb had opposite effects in each tumor model. These data show that position of tumor-initiating cells within a stratified squamous epithelial tissue provokes distinct B- and CD4 T-cell interactions, which establish unique tumor microenvironments that regulate tumor development and response to immunotherapy. Cancer Immunol Res; 5(3); 198–210. ©2017 AACR.
    Type of Medium: Online Resource
    ISSN: 2326-6066 , 2326-6074
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2017
    detail.hit.zdb_id: 2732517-9
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2013
    In:  Cancer Research Vol. 73, No. 8_Supplement ( 2013-04-15), p. 5682-5682
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 73, No. 8_Supplement ( 2013-04-15), p. 5682-5682
    Abstract: Antiangiogenic agents target tumor mechanisms involved in blood vessel formation vital for tumor growth and metastases. However, these agents are mainly cytostatic and usually not tumoricidal. Several combinations of antiangiogenic and cytotoxic agents have shown significant promise in the clinic, and several clinical trials are in progress. Single agents with both antiangiogenic activities and cytotoxicity would afford agents that would circumvent pharmacokinetic problems of multiple agents, avoid drug-drug interactions, could be used at lower doses to alleviate toxicity, be devoid of overlapping toxicities, and could delay or prevent tumor cell resistance. We designed, synthesized and evaluated a novel compound AG119 that inhibits both vascular endothelial growth factor receptor-2 (VEGFR-2) affording antiangiogenic effects and tubulin for cytotoxic effects in a single agent. Structural modifications of AG119 afforded AG321 that inhibited platelet derived growth factor receptor-β (PDGFR-β) and epidermal growth factor receptor (EGFR) in addition to VEGFR-2 and tubulin. The novel compounds AG119 and AG321 were potent inhibitors (activity comparable to that of combretastatin A-4) of bovine brain tubulin assembly and of [3H] colchicine binding to tubulin, indicating that these compounds bind at the colchicine site on tubulin. Both compounds have potency comparable to those of sunitinib and semaxinib in tumor cell lines overexpressing VEGFR-2. AG321 has potency comparable to that of erlotinib in tumor cell lines overexpressing EGFR and potency comparable to those of erlotinib, DMBI and PD153035 in cell lines overexpressing PDGFR-β. Both AG119 and AG321 also inhibited angiogenesis in the chorioallantoic membrane (CAM) assay. AG321 is a unique compound with four separate mechanisms of action in a single agent including inhibition of tubulin. This is unprecedented and to our knowledge, is the first of its kind. In mice, AG119 reduced tumor size and vascularity in two flank xenograft models [the BLBC MDA-MB-435 model and U251 glioma model] and in a 4T1 triple negative breast orthotopic allograft model. In these in vivo models, the activity of AG119 was superior to those of temozolomide (U251), docetaxel and sunitinib (MDA-MB-435 and 4T1) without overt toxicity to the animals. Citation Format: Aleem Gangjee, Roheeth K. Pavana, Michael A. Ihnat, Jessica E. Thorpe, Bryan C. Disch, Anja Bastian, Lora C. Bailey-Downs, Ernest Hamel, Rouli Bai. Design and preclinical evaluation of single agents with combination chemotherapy potential. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5682. doi:10.1158/1538-7445.AM2013-5682
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2013
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2016
    In:  Cancer Research Vol. 76, No. 14_Supplement ( 2016-07-15), p. 3776-3776
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 76, No. 14_Supplement ( 2016-07-15), p. 3776-3776
    Abstract: About fifty percent of breast cancer patients receiving a combination of surgery, radiation and systemic therapy will not remain cancer-free. Most solid tumors, including breast tumors, have hypoxic regions that can contribute to chemoresistance, radioresistance, and poor differentiation in tumors resulting in a poor clinical outcome in patients with advanced disease. It has been reported that mitochondrial respiration remains active in these hypoxic microenvironments. Complex I of the mitochondrial electron transport chain (ETC) has been shown to switch to a de-active catalytic state under hypoxic conditions. The purpose of this study was to investigate the potential anticancer action of a novel compound with antimitochondrial activity under hypoxic conditions. AG311 (5-[(4-Methylphenyl)thio]-9H-pyrimido[4,5-b] indole-2,4-diamine) is a small molecular weight compound shown to inhibit complex I activity in vitro and to drastically reduce mitochondrial oxygen consumption rate by 62.9% at 7.5 μM in breast cancer cells (p & lt;0.001). In two triple negative breast cancer mouse models (MDA-MB-435 and 4T1), AG311 significantly reduced tumor volume by 85% and 81%, respectively (p & lt;0.001 for both). In this current study, the effect of the microenvironment on AG311 mitochondrial inhibition was examined. First, it was shown that AG311 inhibited complex I activity not only in vitro, but also in breast cancer cells (54% inhibition, p & lt;0.001) and tumor homogenate (50% inhibition, p = 0.01). AG311 induced greater cytotoxicity in cells (MDA-MB-435) cultured in glucose-depleted media (IC50 15.5 μM vs 20.0 μM, p & lt;0.01), a condition favoring mitochondrial ATP production, as compared to normal glucose concentrations. Further, co-treatment of AG311 with dichloroacetate, a pyruvate dehydrogenase kinase inhibitor and stimulator of oxidative phosphorylation, showed a synergistic effect on cell kill (CI = 0.7 at 20 μM). Importantly, hypoxic conditions (1% O2) significantly sensitized cancer cells to AG311-induced cell death (from 43.3% to 30.1%, p = 0.019). Further, the effect of AG311 on the deactive form of complex I, which is promoted under hypoxic conditions was assessed by measuring NADH oxidation rate. The switch to the de-active state was thermally-induced in mitochondrial homogenates and once in this state, complex I activity was sensitized to AG311 inhibition (from 45.4% to 65.0% inhibition, p = 0.04). Thus, a mitochondrial inhibitor that preferentially inhibits the de-active state of complex I in hypoxic tumor regions could potentially provide a therapeutic benefit. Citation Format: Anja Bastian, Satoshi Matsuzaki, Kenneth M. Humphries, Lora C. Bailey-Downs, Aleem Gangjee, Michael A. Ihnat. Mechanistic evaluation of AG311 - an OXPHOS inhibitor - as a potential treatment for breast cancer. [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 3776.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2016
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2011
    In:  Cancer Research Vol. 71, No. 8_Supplement ( 2011-04-15), p. 2449-2449
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 71, No. 8_Supplement ( 2011-04-15), p. 2449-2449
    Abstract: Primary cilia are microtubule rich projections eminating from the apical surface of epithelial cells. Primary cilia are responsible for the transduction of growth factor and morphogenetic signaling pathways, including the hedgehog, wnt and platelet-derived growth factor pathways. Initial observations in the field of pancreatic cancer have suggested the absence of primary cilia in human pancreatic intraepithelial neoplasia (PanIN) and pancreatic ductal adenocarcinoma. While absent in the majority of pancreatic cancer cells, primary cilia have been identified in differentiated acinar cells undergoing an acinar to ductal metaplasia. This metaplasia is well characterized in pancreatic injury and regeneration models and accelerates tumor formation in the presence of acinar specific KrasG12D mutations. Thus, we are addressing the hypothesis that primary cilia, while not expressed in bulk tumor populations, are maintained in pancreatic tumor-initiating cells. To address the hypothesis, we have used confocal microscopy to quantify the percentage of cells within low grade human PanIN lesions that express a primary cilium. Performing confocal microscopy on a human PanIN tissue array (n=23), we have determined that in 15% of PanIN lesions, 13-30% of the cells are expressing a primary cilium, as is evidenced by staining for acetylated alpha tubulin. We have also developed a sorting strategy using an acetylated alpha tubulin antibody to isolate ciliated cells by Fluorescence Activated Cell Sorting (FACS) analysis. Using this protocol, we have discovered that human pancreatic cancer cells bearing a primary cilium are markedly enriched in cells also positive for either CD133 or CD24/CD44, representing putative pancreatic cancer stem cell populations. We have functionally analyzed the tumor-initiating capacity of ciliated vs non-ciliated cells using tumor sphere experiments. In this assay, ciliated cells show a significant increase (100 fold) in tumor sphere-forming capacity, suggesting that the presence of a primary cilium may mark a pancreatic cancer tumor initiating population. These data are informative regarding the earliest initiating events in pancreatic cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2449. doi:10.1158/1538-7445.AM2011-2449
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2011
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 76, No. 14_Supplement ( 2016-07-15), p. 530-530
    Abstract: Tumors from stratified epithelium contain proliferating and differentiating compartments, but it is not clear how tumor cells in different layers alternatively engage the immune system. We have established two doxycycline inducible Ras models in which oncogenic RasV12G is targeted to either the epidermal basal/stem cell layer with a Keratin14-rtTA transgene (K14Ras), or suprabasal differentiating cells with an Involucrin-tTA transgene (InvRas). On threshold doxycycline levels yielding similar tumor numbers and Ras expression over 30 days, mice with basal cell targeted Ras developed focal squamous cell carcinoma while suprabasal targeting caused benign squamous papilloma formation. On a Rag1-/- background InvRas mice developed fewer tumors that regressed over time while K14Ras mice developed more tumors with shorter latency than Rag1+/+ controls. Depletion and adoptive transfer studies revealed that naïve B and CD4 T cells together, but not alone, suppressed tumor formation in K14Ras mice but restored tumor numbers in InvRas mice. Tumors developing in K14Ras mice showed a loss of proinflammatory CD4 T and B cells and increased percentages of regulatory cells infiltrating the tumor tissue. In vivo cotransfers show that B and CD4 T cells reciprocally prime each other towards a regulatory phenotype in the K14Ras tumor microenvironment, but in the InvRas tumor microenvironment proinflammatory CD4 T and B cell phenotypes result. Coculture of tumor-conditioned B cells with stimulated naïve CD4 T cells showed an importance of direct contact and CD40/CD40L interactions for the generation of regulatory T cells (Tregs) by B cells in K14Ras mice. In contrast, tumor-conditioned B cells from InvRas mice support generation of proinflammatory CD4 T cells, and antagonize Treg development. This function is restricted to tumor-conditioned B cells, as splenic B cells from tumor-bearing mice had no effect on CD4 T cell phenotype. In vivo blockade of CD40L in K14Ras mice resulted in significantly increased tumor counts as well as reduced B and Treg prevalence. Blockade of CD40L in InvRas mice significantly reduced tumor number, increasing Treg cell count and decreasing neutrophil infiltration into the tumor tissue. Time-course experiments suggest a protective role of Tregs in late stages of K14Ras tumors, and a tumor-promoting role of proinflammatory CD4 T cells in InvRas tumors. Thus, basal/stem cell expression of Ras provokes a regulatory cell inducing microenvironment, suppressing tumor-promoting inflammation in late-stage tumors. Ras expression in differentiating cells activates a tumor promoting proinflammatory phenotype in B and CD4 T cells without provoking immunosurveillance. Taken together, these data show that tumor cell position within a stratified epithelium differentiation hierarchy provokes distinct B and CD4 T cell interactions with opposing effects on tumor development. Citation Format: Michael A. Podolsky, Carrie J. Oakes, Andrew Gunderson, Kyle Breech, Jacob Bailey, Adam B. Glick. Location of oncogene expression within a stratified squamous epithelium drives distinct B and CD4 T-cell crosstalk to dictate the tumor immune response. [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 530.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2016
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2012
    In:  Cancer Research Vol. 72, No. 8_Supplement ( 2012-04-15), p. 1554-1554
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 72, No. 8_Supplement ( 2012-04-15), p. 1554-1554
    Abstract: Pancreatic ductal adenocarcinoma (PDA) is a leading cause of cancer mortality with a dismal 2-5% 5-year survival rate. Monotherapy with Gemcitabine has limited success, highlighting the need for additional therapies that enhance the efficacy of current treatments. We evaluated the combination of Gemcitabine and Rosiglitazone Maleate, an FDA-approved drug for the treatment of type II diabetes, in an immunocompetent transplantable mouse model of pancreatic cancer. Tumor progression, survival and metastases were evaluated in mice with subcutaneous or orthotopic pancreatic tumors treated with Pioglitazone, Rosiglitazone, Gemcitabine or combinations of these. We characterized the impact of high dose Rosiglitazone and Gemcitabine therapy on immune suppressive mediators, including MDSC and T regulatory cells, and on modulation of peripheral and intra-tumoral T cell populations. Combinations of Rosiglitazone and Gemcitabine significantly reduced tumor progression and metastases, enhanced apoptosis, and significantly extended overall survival compared to Gemcitabine alone. Rosiglitazone altered tumor-associated immune suppressive mediators by limiting early MDSC accumulation and intra-tumoral T regulatory cells. Combination therapy with Rosiglitazone and Gemcitabine modulated T cell populations by enhancing circulating CD8+ T cells and intra-tumoral CD4+ and CD8+ T cells while limiting T regulatory cells. The results suggest that Rosiglitazone, in combination with Gemcitabine, decreases immune suppressive mechanisms in immunocompetent animals and provide pre-clinical data in support of combining Rosiglitazone and Gemcitabine as a clinical therapy for pancreatic cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1554. doi:1538-7445.AM2012-1554
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2012
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2012
    In:  Cancer Research Vol. 72, No. 8_Supplement ( 2012-04-15), p. 2308-2308
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 72, No. 8_Supplement ( 2012-04-15), p. 2308-2308
    Abstract: MUC1, a cell-surface glycoprotein implicated in tumorigenesis and metastasis, has a cytoplasmic tail (MUC1.CT) that is phosphorylated by different receptor tyrosine kinases and conducts these signals by binding and altering the function or stability of transcription factors, thereby influencing gene transcription. MicroRNAs (miRNAs), short RNAs (19-22 nucleotides), regulate gene expression at the transcriptional level and are differentially regulated in cancer and metastasis. We discovered that MUC1.CT influences expression of miRNAs that contribute to metastasis, including miR-200c. MiR-200c is a known regulator of epithelial-to-mesenchymal transition (EMT) through regulation of ZEB1, a transcriptional repressor of E-cadherin. In addition, ZEB1 is a repressor of miR-200c in a feedback loop. Overexpression of MUC1 results in a dramatic decrease in miR-200c levels, resulting in increased levels of ZEB1. Chromatin immunoprecipitation (ChIP) was used to demonstrate that MUC1.CT occupies the ZEB1 binding motif upstream of the miR-200c start site. In addition, we found that ZEB1 occupancy of the miR-200c promoter region was enhanced 3.5-fold in MUC1 overexpressing cells, indicating that MUC1.CT may influence the expression and stability of ZEB1 at the miR-200c promoter. Co-immunoprecipitation experiments determined that MUC1.CT directly interacts with ZEB1. We evaluated levels of proteins affected by the miR-200c pathway in MUC1 overexpressing cells and observed an increase in ZEB1 levels and a decrease in E-cadherin levels, consistent with induction of EMT. We also confirmed an increase of ZEB1 occupancy at the E-cadherin promoter in MUC1 overexpressing cells, further confirming our hypothesis. In addition, MUC1.CT is differentially phosphorylated by several receptor tyrosine kinases. Antibodies against different phospho-isoforms were used with ChIP to investigate the signaling cascades that influence localization of the MUC1.CT to the miR-200c promoter. The phospho-YEKV form of MUC1.CT, which is representative of signaling through epidermal growth factor/receptor (EGF/EGFR), was the only phospho-MUC1.CT detected at the ZEB1 binding motif of the miR-200c promoter. EGF signaling is linked to a loss of E-cadherin, and our work is the first to link EGF signaling through the MUC1.CT as a direct regulator of miR-200c expression. These data portray a novel pathway of EMT modulation. EGF signaling via MUC1 regulates levels of miR-200c, altering regulation E-cadherin. Grant support was provided by grants from the NCI (Training Grant CA09476, R01CA57362, U01 CA111294) and student assistantships from UNMC. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2308. doi:1538-7445.AM2012-2308
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2012
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2013
    In:  Cancer Research Vol. 73, No. 8_Supplement ( 2013-04-15), p. 1389-1389
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 73, No. 8_Supplement ( 2013-04-15), p. 1389-1389
    Abstract: Physiologically relevant animal models of micrometastasis are lacking; yet micrometastasis activation leading to macrometastasis and/or recurrent tumors is a major cause of cancer mortality and treatment resistance. Tumor cell implantation metastasis models typically use large numbers of tumor cells and immune compromised rodents together with removal of primary tumors to maximize the number, size and speed of macrometastases. Genetic and chemical/physical tumorigenesis models are often inconveniently slow and do not provide consistent metastasis. In order to develop a platform for investigating the biology of micrometastasis and for drug development to target micrometastases, we developed a model to study this phenomenon in vivo. The 4T1 triple negative syngeneic breast cancer model was chosen without resection of the primary tumor. A cell titration from 100,000 to 500 4T1-GFP tagged cells was first completed, with cells implanted into fat pad 3 of immune proficient 8 wk female BALB/c mice. Implantation of 15,000-100,000 cells resulted in 90-100% primary tumor take by 7 days; a small number (less than 15) micrometastases into the lungs by 2 wk; 70-90% of the animals having macrometastases (as evidenced by a distinct blood supply using tetrarhodamine labeled dextran) by 4 wk; and with most animals becoming moribund by 5 wk. Implantation of 7,500 cells resulted in & gt;90% tumor take by 10 days; in 30-250 micrometastases in the lung (with many animals having 5-10 brain micrometastases) 2 wk post-implantation; with the first small macrometastases present at 4 wk; with most (80%) animals having macrometastases at 5 wk and animals becoming moribund by 6 wk post-implantation. With animals seeded with 500-1500 cells, the time of micrometastasis to macrometastasis conversion and animal survival could be prolonged, though primary tumor take was less (40-60%) than with 7,500 cells. Finally, this model using 7,500 cells was used to test the efficacy of a first-line chemotherapeutic agent for breast cancer, docetaxel, given at its maximal tolerated dose (MTD; 30 mg/kg weekly). Although primary tumor growth could be significantly reduced by docetaxel (P & lt;0.01; two way ANOVA/repeated measures post-test), the number of micro and macrometastases at the experiment end was not significantly affected by docetaxel treatment and animal weight, a measure of systemic toxicity, was significantly reduced in the docetaxel group (P & lt;0.01, unpaired two-tailed students’ t-test). Citation Format: Michael A. Ihnat, Lora C. Bailey-Downs, Jessica E. Thorpe, Bryan C. Disch, Anja Bastian, Taleah C. Farasyn, Paul J. Hauser, Robert E. Hurst. Development and characterization of a natural model of triple negative breast micrometastasis. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1389. doi:10.1158/1538-7445.AM2013-1389
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2013
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages