bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4980: Engineering adoptive T cell therapy for efficacy in ovarian cancer
Authors: Anderson Kristin G. , Bates Breanna M. , Chiu Edison Y. , Greenberg Philip D.
Published: July 2017

Over 20,000 women are diagnosed with ovarian cancer annually - more than half will die within 5 years and this rate has changed very little in the last 20 years, highlighting the need for innovative therapies. One promising new treatment strategy has the potential to control tumor growth without toxicity to healthy tissues, by employing immune T cells engineered to target proteins uniquely overexpressed in tumors. Recent technological advances have helped identify and validate Wilms’ Tumor Antigen 1 (WT1) and mesothelin (MSLN) as valid antigen targets for ovarian cancer, as these proteins contribute to malignant and invasive phenotypes and have limited expression in healthy cells. In preclinical studies using either patient-derived cell lines or the mouse ID8 ovarian tumor model, we found that T cells engineered to express either a WT1- or MSLN- specific high-affinity T cell receptor (TCR) can kill human and murine ovarian tumor cells in vitro. Moreover, in a disseminated in vivo murine model, adoptively transferred TCR-engineered T cells preferentially accumulated within established ID8 tumors, delayed ovarian tumor growth and prolonged mouse survival. However, our data also revealed that the tumor microenvironment (TME) can limit engineered T cell persistence and killing capacity. Cellular and molecular analyses showed human therapy will face similar TME-mediated obstacles. The ovarian cancer TME is a nutrient- and oxygen-deprived milieu, and adaptive metabolic responses by infiltrating T cells have protean effects on T cell function. Thus, strategies that modulate T cell metabolic pathways, and thereby influence activity in the TME, might enhance T cell function and improve anti-tumor efficacy by overcoming a critical component of immune evasion by solid tumors. Ongoing studies will be discussed that are exploring strategies to overcome elements common to the human and murine TME, including direct modulation of the environment and T cell engineering to promote T cell survival and function.

Citation Format: Kristin G. Anderson, Breanna M. Bates, Edison Y. Chiu, Philip D. Greenberg. Engineering adoptive T cell therapy for efficacy in ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4980. doi:10.1158/1538-7445.AM2017-4980
Abstract 4985: Understanding the vulnerabilities in cancer cells upon inhibition of glutathione synthesis
Authors: Harris Isaac S. , Endress Jennifer E. , Brugge Joan S.
Published: July 2017

A hallmark of cancer is the rewiring of cellular metabolic pathways, including those that mediate oxidative stress. Cancer initiation and progression, which demands increased production of ATP and synthesis of proteins, also results in elevated generation of toxic by-products such as reactive oxygen species (ROS). Cancer cells counteract ROS by increasing the production of antioxidants, which convert ROS into benign species. It has been shown that production of glutathione (GSH), the most abundant intracellular antioxidant, is necessary for many cancers to initiate malignant transformation. Whether inhibition of GSH synthesis can impact the survival of established malignant tumors remains poorly understood. In this study we investigated the extent to which GSH is required in cancer cells and across different subtypes of breast cancer. Profiling of an extensive panel of breast cancer cell lines demonstrated that the majority of cells are resistant to death after acute GSH depletion, while only luminal breast cancer cells are sensitive to chronic GSH depletion. To understand how most tumor cells are resistant to GSH depletion and oxidative stress, we conducted a small-molecule high-throughput screen interrogating more than 500 compounds in a 10-point dilution format. Importantly, screening plates were imaged and cell numbers quantified to avoid any false positives/negatives potentially associated with interrogating cellular metabolism using classical high throughput techniques, such as CellTiter-Glo. This screen revealed that depletion of glutathione sensitized breast cancer cells to inhibition of deubiquitinases, resulting in a drastic induction of a proteotoxic stress response. Furthermore, this sensitivity was found to be specific to malignant cells, as non-transformed cells were resistant to the combined treatments. It has been hypothesized that GSH, acting as an abundant thiol group, non-enzymatically reacts with ubiquitin and limits ubiquitination of proteins. Loss of glutathione, in combination with deubiquitinase inhibitors, leads to deregulation of ubiquitinated protein pools, and cancer cells undergo proteotoxic stress and cell death. These findings elucidate a novel vulnerability in cancers cells and shed light on an unexpected relationship between cancer metabolism and protein homeostasis.

Citation Format: Isaac S. Harris, Jennifer E. Endress, Joan S. Brugge. Understanding the vulnerabilities in cancer cells upon inhibition of glutathione synthesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4985. doi:10.1158/1538-7445.AM2017-4985
Abstract 4986: Pancreatic cancers develop metabolic resistance pathways to glutaminase inhibition
Authors: Mancias Joseph D. , Biancur Douglas E. , Paulo Joao A. , Rey Maria Quiles Del , Sousa Cristovão M. , Wang Xiaoxu , Chu Gerald C. , Gygi Steven P. , Harper J. Wade , Kimmelman Alec C.
Published: July 2017

Pancreatic ductal adenocarcinoma (PDAC) is an extremely aggressive disease with poor prognosis. Therefore, novel treatment options are essential to combat this highly refractory disease. Oncogenic Kras can promote a metabolic rewiring of pancreatic cancers, including the non-canonical use of glutamine to support growth and proliferation through redox homeostasis. Indeed, inhibition of downstream components of glutamine metabolism leads to a decrease in tumor growth. The first step in glutamine metabolism is mediated by the enzyme glutaminase (GLS) which catalyzes the conversion of glutamine to glutamate in the mitochondria where, in PDAC, glutamine-derived glutamate is metabolized ultimately resulting in increased reducing potential in the form of increased NADPH and GSH. An outstanding question in pancreatic cancer is whether GLS inhibition is a viable therapeutic strategy given it is the most proximal enzyme in the PDAC-specific glutamine metabolism pathway, and how this may differ from targeting distal parts of the pathway. Using a combination of in vitro and in vivo models of pancreatic cancer, we tested whether recently developed highly potent inhibitors of GLS are an effective therapy for PDAC. We demonstrate that despite dramatic early effects on in vitro proliferation caused by GLS inhibition, pancreatic cancer cells have adaptive metabolic networks that allow them to sustain proliferation in vitro and in vivo. Through an integrated proteomic and metabolomic analysis, we identify multiple compensatory pathways that may explain the resistance to GLS inhibition and show as proof of concept that combining inhibitors to these pathways with GLS inhibitors may have therapeutic utility.

Citation Format: Joseph D. Mancias, Douglas E. Biancur, Joao A. Paulo, Maria Quiles Del Rey, Cristovão M. Sousa, Xiaoxu Wang, Gerald C. Chu, Steven P. Gygi, J. Wade Harper, Alec C. Kimmelman. Pancreatic cancers develop metabolic resistance pathways to glutaminase inhibition [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4986. doi:10.1158/1538-7445.AM2017-4986
Abstract 4987: ASS1 downregulation facilitates cancer cell survival in acidic environment
Authors: Erez Ayelet , Silberman Alon , Jacob Adi , Limanovich Shiran , Boukobza1 Odeya , Persi Erez , Keshet Rom , Sarver Alona , Lee Joo Sang , Brandis Alexander , Halpern Keren Bahar , Eilam Raya , Pode Ben , Anikster Yair , Ulitsky Igor , Nagamani Sandesh , Ruppin Eytan
Published: July 2017

”pH gradient reversal”, namely the alkalinization of intracellular pH (pHi) and acidification of extracellular pH (pHe), is a unique phenotype of cancer cells which enable cancer survival, migration and invasion. Hence, not surprisingly, pH gradient reversal is emerging as a new hallmark of cancer. Argininosuccinate synthase, ASS1, is a urea cycle enzyme found to be downregulated by methylation in multiple different types of cancers in correlation with increased metastasis and poor prognosis. We recently showed that ASS1 downregulation increases proliferation by channeling aspartate towards pyrimidine synthesis by CAD. We now show that under hypoxia and acidic environments, ASS1 is downregulated together with CAD by HIF1α as part of an essential network necessary for cancer cells’ survival, invasion and migration. Similar to germline deficiency of ASS1 which increases the levels of glutamine and ammonia, ASS1 downregulation by HIF1αenables the cancer cells to increase glutamine levels allowing its utilization for glutathione and importantly, for preservation of alkali pHi by elevating ammonia levels and buffering the acidity caused by cancers’ enhanced glycolysis and the consequent increase in lactic acid. Moreover, cancer cells which express ASS1 when grown in culture, downregulate its expression in hypoxic regions when grown in vivo, suggesting that these cancers might also be sensitive to drugs previously utilized only in ASS1 deficient cancers. Finally, we show that treating cancers with ASS1 deficiency with ammonia scavengers as given to ASS1 deficient patients, increases apoptosis and restricts migration, and is hence beneficial therapeutically. In summary, ASS1 downregulation is regulated differently at altered carcinogenic states, promoting proliferation as well as cancer survival and metastasis.

Citation Format: Ayelet Erez, Alon Silberman, Adi Jacob, Shiran Limanovich, Odeya Boukobza1, Erez Persi, Rom Keshet, Alona Sarver, Joo Sang Lee, Alexander Brandis, Keren Bahar Halpern, Raya Eilam, Ben Pode, Yair Anikster, Igor Ulitsky, Sandesh Nagamani, Eytan Ruppin. ASS1 downregulation facilitates cancer cell survival in acidic environment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4987. doi:10.1158/1538-7445.AM2017-4987
Abstract 4988: Genome-wide CRISPR screen and metabolite profiling reveal a new mechanism of methotrexate sensitivity
Authors: Kanarek Naama , Freinkman Elizaveta , Cantor Jason , Abu-Remaileh Monther , Wang Tim , Sabatini David M.
Published: July 2017

The chemotherapeutic drug methotrexate (MTX) inhibits nucleotide biosynthesis and causes cell death by blocking DNA and RNA production. While MTX has had tremendous success as an anti-cancer treatment and is the subject of nearly a thousand ongoing clinical trials, we do not fully understand why certain cancers are more sensitive to it and why resistance emerges. To study these questions, we used a CRISPR-based genetic screen to identify genes that confer sensitivity to MTX. We identified an enzyme that plays a key role in a metabolic pathway that was not known to be associated with MTX sensitivity. Inhibition of the pathway, either by genetic loss of several genes in the pathway or through nutritional modulations, causes dramatic resistance to MTX in cultured cancer cells. Our results improved our understanding of the cellular response to MTX, and suggest that expression levels of enzymes in the pathway may serve as clinical predictor for MTX response in patients.

Citation Format: Naama Kanarek, Elizaveta Freinkman, Jason Cantor, Monther Abu-Remaileh, Tim Wang, David M. Sabatini. Genome-wide CRISPR screen and metabolite profiling reveal a new mechanism of methotrexate sensitivity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4988. doi:10.1158/1538-7445.AM2017-4988
Abstract 499: IgH enhancers hs3b/hs4 are dispensable for c-Myc deregulation in mouse plasmacytomas with T(12;15) translocations
Authors: Kovalchuk Alexander L. , Morse Herbert C.
Published: July 2017

c-Myc deregulating t(12;15) chromosomal translocation is the hallmark cytogenetic abnormality of murine plasmacytomas (PCTs). In the great majority of PCTs, the immunoglobulin heavy chain (IgH) locus is broken between Eμ enhancer and the 3’ regulatory region (3’RR), making the latter the major candidate for orchestrating c-Myc deregulation. To elucidate the role of 3’RR in tumorigenesis, we induced PCTs in mice deficient for the major 3’RR enhancer elements, namely hs3b and hs4 (3’KO). Unexpectedly, and contrary to the previous observations made in a mouse lymphoma model, Hs3b/Hs4 3’KO mice did develop t(12;15)-positive PCTs, although with a lower incidence than wild-type controls. In heterozygous mice, there was no allelic bias in targeting IgH for the t(12;15). Molecular analysis of IgH/Myc junctions revealed dominance of Sμ region breakpoints compared to the prevalence of hits into Sγ or Sα in the controls. Analysis of c-Myc expression as well as Ig secretion in 3’KO PCT cell lines revealed no significant differences from the controls. Our current findings highlight the complexity of the 3’RR and the potential of its components to compensate for each other in the context of differentiation from B-lymphocyte to plasma cell. We next extended our observations to include a PCT model where Cre-mediated deletion can remove all four 3'IgH enhancers: hs3a, hs1,2, hs3b and hs4. In PCT cell lines where c-Myc is translocated to an IgH BAC transgene with a floxed 3’IgH enhancer region, induction of retrovirally-expressed Cre-recombinase causes gradual Myc downregulation and complete cell death within 96 hours. The later observation confirms the requirement of the full 3’RR for c-Myc deregulation by T(12;15).

Citation Format: Alexander L. Kovalchuk, Herbert C. Morse. IgH enhancers hs3b/hs4 are dispensable for c-Myc deregulation in mouse plasmacytomas with T(12;15) translocations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 499. doi:10.1158/1538-7445.AM2017-499
Abstract 4999: Stress, spiritual wellbeing and cancer risk among diverse racial faith-based communities: Elevated levels of stress proteomic biomarkers in breast cancer patients
Authors: Uppala Padma P. Tadi , Krivak Gretchen , Brown-Fraser Sherine , Anjejo Dixon , Mejia Alfredo , wakefield Dominique , Kolli Kumar
Published: July 2017

Spiritual wellbeing is associated with decreased risk for cancer. Stress and depression are common among cancer patients and may be inversely associated with spiritual wellbeing. The purpose of the study is to examine if stress and depression as indicators of cancer risk are lower in a racially diverse faith-based community. Methods: 752 individuals from a faith-based community completed a behavioral assessment survey that mapped the current patterns of behavior in key categories that include: stress, depression, exercise and nutrition using the E-wellness platform FitThumb. To identify stress biomarkers in cancer patients we examined levels of stress serum proteomic biomarkers that were previously identified in our study by proteomic profiling using 2D-DIGEMS analysis and a subset of samples by shotgun LCMS technology. The serum proteomic study included serum samples from 15 African American breast cancer patients and 12 healthy controls who were from a faith-based community. Results: The behavioral assessment surveys that included 752 individuals who were racially diverse showed a low stress risk of 47.74% vs 8.24 % of high stress risk for chronic disease; and low depression risk of 85.11% vs 1.99% high risk for chronic disease. Elevated levels of stress and inflammatory serum proteomic biomarkers such as ceruloplasmin known to increase in stressed animals and humans; heptaglobin, apolipoproteins, and heat shock proteins were significantly elevated in breast cancer patients compared to healthy controls. Conclusions: Our results indicate that spiritual well-being is associated with significantly low stress and depression in a faith-based community regardless of race or ethnicity, posing a low risk for cancer as shown in previous Adventist Health Cohort studies. Future efforts will focus on validating and identifying panel of biomarkers from this cohort to gain insight into their role(s) in the mechanisms of stress hormones and cancer risk. Funded by Susan G Komen for the cure.

Citation Format: Padma P. Tadi Uppala, Gretchen Krivak, Sherine Brown-Fraser, Dixon Anjejo, Alfredo Mejia, Dominique wakefield, Kumar Kolli. Stress, spiritual wellbeing and cancer risk among diverse racial faith-based communities: Elevated levels of stress proteomic biomarkers in breast cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4999. doi:10.1158/1538-7445.AM2017-4999
Abstract 500: Impairment of DNA double strand break repair in human primary alveolar type II cells in emphysema
Authors: Kosmider Beata , Vlasenko Liudmila , Marchetti Nathaniel , Bolla Sudhir , Mandapati Chenna , Xander Nathaniel , Criner Gerard , Bahmed Karim
Published: July 2017

Rationale Emphysema is caused by the destruction of alveolar wall septa. The major risk factor for this disease is cigarette smoke and effective therapies are very limited. Alveolar type II (ATII) cells are in the gas exchange portion of the lung. They make and secrete pulmonary surfactant, and proliferate to restore the epithelium after damage to the more sensitive alveolar type I cells.

Methods Control ATII cells were isolated from deidentified control non-smoker and smoker organ donors whose lungs were not suitable for transplantation and donated for medical research. Furthermore, as a unique approach, we have developed a new method on how to isolate ATII cells from excess tissue from lung transplants obtained from patients with emphysema using magnetic microbeads. We determined DNA damage, DNA repair, oxidative stress, injury, and inflammation in human primary ATII cells isolated from these individuals in comparison with controls.

Results Our data indicates high oxidative stress in human ATII cells induced by cigarette smoke extract in vitro as measured by 4-HNE staining by immunocytofluorescence. We also observed DNA double strand breaks, high DNA damage, and low DNA repair in these cells. Moreover, we found greater proinflammatory response as determined by IL-8 and IL-6 levels by ELISA. Furthermore, ATII cells obtained from patients with emphysema had greater injury compared to cells obtained from control non-smokers and smokers.

Conclusion Our results indicate oxidative ATII cell damage induced by cigarette smoke and in emphysema. Observed DNA damage/repair imbalance may contribute to cell death in this disease. The study of ATII cell injury may improve our knowledge on this disease pathogenesis and may lead to novel therapeutic strategies to slow the progression of emphysema.

Note: This abstract was not presented at the meeting.

Citation Format: Beata Kosmider, Liudmila Vlasenko, Nathaniel Marchetti, Sudhir Bolla, Chenna Mandapati, Nathaniel Xander, Gerard Criner, Karim Bahmed. Impairment of DNA double strand break repair in human primary alveolar type II cells in emphysema [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 500. doi:10.1158/1538-7445.AM2017-500
Abstract 5007: Role of the interferon-gamma response pathway in immune escape of colorectal carcinoma
Authors: Britzen-Laurent Nathalie , Straube Julia , Tripal Philipp , Waldner Maximilian , Becker Christoph , Merkel Susanne , Croner Roland S. , Sturzl Michael
Published: July 2017

The presence of an interferon-dominated Th1 immune response in colorectal carcinoma (CRC) has been associated with improved clinical outcome. We have previously identified the guanylate-binding protein 1 (GBP-1), one of the major IFN-γ-induced proteins, as a marker for the Th1 immune response and an independent positive prognostic factor in CRC. We also found that GBP-1 is a necessary mediator of the anti-tumorigenic effects of IFNγ. Interestingly, the expression of GBP-1 in CRC was observed more frequently in the desmoplastic stroma than in the directly adjacent tumor cells, suggesting that CRC tumor cells might become resistant to IFN-γ in the course of tumorigenesis. Indeed, we found that several colorectal carcinoma cell lines failed to express GBP-1 or other interferon-stimulated genes after treatment with IFN-γ, and were resistant to IFN-γ-induced apoptosis or proliferation inhibition. In these cell lines, the loss of IFN-γresponsiveness correlated either with the down-regulation of the IFN-γ receptor alpha chain (IFNγRα) or with the presence of a mis-glycosylated form of IFNγRα, which displayed an aberrant intracellular localization. We further validated these findings at the clinical level by showing that the expression of IFNγRα is decreased in CRC compared to normal tissue. In addition, the down-regulation of IFNγRα expression in CRC correlated with a reduced cancer-related survival together with a higher rate of distant metastasis. In addition, in-vivo colon tumorigenesis models using conditional knock-out mice revealed that the absence of IFNγRα expression by intestinal epithelial cells fosters tumor growth. Altogether, our data suggest that the loss of IFN-γ responsiveness is a common event in CRC and protects tumor cells against the anti-tumorigenic effects of IFN-γ.

Citation Format: Nathalie Britzen-Laurent, Julia Straube, Philipp Tripal, Maximilian Waldner, Christoph Becker, Susanne Merkel, Roland S. Croner, Michael Sturzl. Role of the interferon-gamma response pathway in immune escape of colorectal carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5007. doi:10.1158/1538-7445.AM2017-5007
Abstract 5009: Self-renewal of hypoxic glioma stem-like cells is facilitated by secretion-mediated STAT3 activation
Authors: Bonnin Damian A. Almiron , Havrda Matthew C. , Liu Huan , Lee Myung Chang , Ung Matthew H. , Cheng Chao , Israel Mark A.
Published: July 2017

Glioblastoma, a type of high-grade glioma, is the most common and the most aggressive primary brain tumor of adults. The median survival is 12-15 months. Despite multimodality treatment, most high-grade gliomas eventually recur and are ultimately incurable. Several studies suggest that the initiation, progression, and recurrence of gliomas are driven at least partly by cancer stem-like cells. A defining characteristic of these cancer stem-like cells is their capacity to self-renew. We have identified a pathway dependent upon tumor hypoxia, a commonly found pathologic feature of GBM, that promotes self-renewal through the HIF1α-JAK1/2-STAT3 axis. Under hypoxic conditions, the expression of HIF1α is greatly increased in GBM stem-like cells leading to the activation of JAK1/2-STAT3 which mediates enhanced tumor stem-like cell self-renewal. Our data further demonstrate the importance of VEGF secretion for this pathway of hypoxia-mediated self-renewal. Using tumor stem-like cells derived from the S100β-v-erbB/p53-/- mouse model of spontaneous high-grade glioma, we have discovered that the activation of STAT3 through hypoxia-mediated VEGF secretion is required for self-renewal of glioma stem-like cells. Media conditioned by these S100β-v-erbB/p53-/- tumor sphere cells cultured under hypoxic conditions promoted self-renewal in S100β-v-erbB/p53-/- glioma stem-like cells and depletion of VEGF from this media was sufficient to inhibit STAT3 phosphorylation. Moreover, we have been able to identify two drugs: Brefeldin A and EHT-1864, that significantly inhibit VEGF secretion, decrease stem cell self-renewal, inhibit tumor growth, and increase the survival of mice allografted with S100β-v-erbB/p53-/- glioma stem-like cells. Cells treated with these drugs express molecular signatures that correlated strongly with the increased survival of GBM patients. These findings suggest a novel treatment strategy to inhibit hypoxia-mediated self-renewal of glioma stem-like cells in high-grade gliomas by targeting the secretion of extracellular, paracrine mediators of self-renewal.

Citation Format: Damian A. Almiron Bonnin, Matthew C. Havrda, Huan Liu, Myung Chang Lee, Matthew H. Ung, Chao Cheng, Mark A. Israel. Self-renewal of hypoxic glioma stem-like cells is facilitated by secretion-mediated STAT3 activation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5009. doi:10.1158/1538-7445.AM2017-5009
Abstract 5010: Activation of the notch signaling pathway confers a tumor-suppressive phenotype on melanoma-associated fibroblasts
Authors: Shao Hongwei , Moller Mecker G. , Cai Long , Zhang Leiming , Liu Zhao-Jun
Published: July 2017

Objectives. The tumor microenvironment (TME) is an emerging therapeutic target for cancer treatment. Cancer-associated fibroblasts (CAF) play a crucial role in cancer progression. We aim to target TME by altering intracellular signaling which determines the biological function of CAF. We have recently showed that the Notch signaling pathway likely functions as a molecular switch in controlling the tumor regulatory role of CAF in animal models and experimentally created “CAF”. Here, we investigated the status of Notch signaling in human melanoma-associated fibroblasts (MAF) versus their normal counterparts and tested whether manipulation of the Notch pathway activity in MAF alter their tumor-regulating function.

Methods. We examined levels of Hes1, a canonical Notch target, in MAF of human malignant melanoma at different stages (I-IV) and fibroblasts in either adjacent or non-adjacent normal skin tissues using tissue microarray. MAF were isolated from human metastatic melanoma tissues. Notch pathway RT2-PCRArray and immunoblot were used to assess Notch pathway activity in MAF versus normal human dermal fibroblasts. Activation of Notch signaling pathway in MAF was achieved by lentiviral vector encoding active form of Notch1 (NIC). The effect of Notch1-engineered MAF on melanoma growth was tested by in vitro co-cultures and in a mouse co-xenograft model (n=6/group). Tumor angiogenesis was analyzed by immunochemistry.

Results. MAF expressed decreased levels of Hes1 compared with adjacent skin fibroblasts. Isolated MAF also exhibited lower Notch activity than normal human dermal fibroblasts. Notch1-engineered MAF significantly inhibited melanoma cell growth in vitro (p<0.01) and suppressed melanoma growth and tumor angiogenesis in mice (p<0.05).

Conclusions. Notch pathway activity is down-regulated in MAF. Increase of Notch pathway activity confers MAF with inhibition to melanoma growth and tumor angiogenesis. Our study demonstrates that Notch signaling is a critical molecular switch in determining the tumor regulatory role of MAF and provides potential targets for cancer therapeutic interventions on the TME.

Citation Format: Hongwei Shao, Mecker G. Moller, Long Cai, Leiming Zhang, Zhao-Jun Liu. Activation of the notch signaling pathway confers a tumor-suppressive phenotype on melanoma-associated fibroblasts [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5010. doi:10.1158/1538-7445.AM2017-5010
Abstract 5014: Drug discovery for NF1-associated malignant peripheral nerve sheath tumors using the zebrafish model
Authors: Ki Dong Hyuk , He Shuning , Look A. Thomas
Published: July 2017

Children and young adults with type 1 neurofibromatosis (NF1) are at risk to develop plexiform neurofibromas, which can undergo malignant transformation to malignant peripheral nerve sheath tumors (MPNSTs). MPNSTs are among the most frequently occurring sarcomas in children and young adults and are especially problematic in NF1 patients. Currently, complete surgical excision is the only curative therapy for NF1-associated MPNST, but these tumors are often not completely resectable. Therefore, it is very important to identify promising drugs that can be rapidly moved into clinical trials to improve the therapy of patients with MPNSTs. We have developed a faithful zebrafish model of NF1-associated MPNST by using genome engineering to develop zebrafish lines harboring loss-of-function mutations of the duplicated nf1a and nf1b genes and p53. Our nf1 and p53 deficient zebrafish models develop MPNSTs that are very similar to human NF1-associated MPNST, and thus are ideal for experiments to test the efficacy of FDA-approved small molecule drugs in vivo. To test the FDA-approved drugs for activity against MPNST tumor cells, about 100 Sox10:mCherry expressed MPNST primary tumor cells were transplanted into dechorionized 2 day-post-fertilization (dpf) larval fish using a micro-injector. MPNST-implanted embryos were exposed to individual test compounds added to the fish water at a range of concentrations and to the vehicle control. After 4-days of treatment, quantitative assessment of the remaining mCherry-labeled tumor cell numbers were measured using the ImageJ software for each treated embryo. Currently, trametinib and sunitinib caused marked antitumor effects indicated by reduced numbers of mCherry-labeled nf1-deficient MPNST cells compared to the DMSO control in this study. We are now applying this embryonic implantation assay to identify combinations of FDA-approved drugs that have a high degree of efficacy against MPNST and can be rapidly “repurposed” to improve the treatment of this disease.

Citation Format: Dong Hyuk Ki, Shuning He, A. Thomas Look. Drug discovery for NF1-associated malignant peripheral nerve sheath tumors using the zebrafish model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5014. doi:10.1158/1538-7445.AM2017-5014
Abstract 5017: Visualization of the mechanisms of metastasis within a biomimetic engineered tumor microenvironment encompassing a perfusable cylindrical 3D microvessel
Authors: Wong Andrew D. , Silvestri Vanesa , Ewald Anderw J. , Searson Peter C.
Published: July 2017

Metastasis is responsible for the majority of cancer related deaths; however, many of the biological and physical details surrounding the critical steps (e.g. invasion and intravasation) are largely unknown, in part due to the difficulty in recapitulating and visualizing these dynamic processes. To elucidate these mechanisms, we have developed an in vitro model of invasion and intravasation that comprises tumor cells embedded within an extracellular matrix (ECM) surrounding an engineered microvessel. The microvessel is cylindrical, 150 µm in diameter, and lined with endothelial cells forming a functional barrier that is maintained under constant perfusion at a shear stress of 2-8 dyne cm-2. Using this biomimetic tumor-microvessel platform, we have previously visualized invasion and intravasation of single MDA-MB-231 breast cancer cells into the microvessel and escape into flow. Here, we present mechanistic details of intravasation from both single tumor cells (MDA-MB-231) and mouse mammary tumor organoids (MMTV-PyMT). For single cells, we observe a mitosis-mediated mechanism of intravasation where tumor cell entry into flow is prefaced by cell division at the ECM-vessel interface. For tumor organoids, we see vascular deformation and destabilization from growing tumors that impinge upon proximal vessels, and that bulk intravasation is mediated by shear stress and tumor cell adhesion. As we characterize the various ways in which tumor cells interact with the vessel endothelium and intravasate, we can explore strategies involving the tumor vasculature and clinically relevant drugs to inhibit critical steps in the metastatic cascade.

Citation Format: Andrew D. Wong, Vanesa Silvestri, Anderw J. Ewald, Peter C. Searson. Visualization of the mechanisms of metastasis within a biomimetic engineered tumor microenvironment encompassing a perfusable cylindrical 3D microvessel [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5017. doi:10.1158/1538-7445.AM2017-5017
Abstract 5023: Disruption of Monocarboxylate transporter-4 Basigin interaction as an effective strategy to inhibit hypoxic response, tumor growth and vascularization, and stem cell phenotype in human glioblastoma in vitro and in vivo
Authors: Spina Raffaella , Voss Dillon M. , Lim Kah Suan , Jeffery Constance J. , Bar Eli E.
Published: July 2017

Monocarboxylate transporters, constitute a family (SLC16) of proton-linked plasma membrane transporters that carry molecules containing a single carboxylate group across biological membranes. Basigin (CD147), is involved in many physiological functions during early stages of development and in cancer. Basigin has been shown to be required for functional plasma membrane expression of Monocarboxylate transporter-1 and Monocarboxylate transporter-4. Using a cell-based screening assay, we identified acriflavine, a small molecule that inhibits the binding between Basigin and Monocarboxylate transporters in vitro and in vivo. Surface Plasmon Resonance analysis confirmed direct binding of acriflavine to Basigin’s immunoglobulin extracellular domain with a low binding constant (kD) of 0.16µM. Acriflavine inhibits normoxic growth of glioma stem cells in vitro and this activity is augmented by hypoxia or by expression of oxygen-stable mutant forms of HIF-1α or HIF-2α. Treatment of mice bearing established glioma stem cell-derived xenografts resulted in inhibition of tumor growth. Acriflavine treatment inhibited intratumoral expression of the angiogenic cytokine vascular endothelial growth factor and tumor vascularization. Our work shows that disruption of monocarboxylate transporter binding to Basigin is an effective approach to target glioma stem cells.

Citation Format: Raffaella Spina, Dillon M. Voss, Kah Suan Lim, Constance J. Jeffery, Eli E. Bar. Disruption of Monocarboxylate transporter-4 Basigin interaction as an effective strategy to inhibit hypoxic response, tumor growth and vascularization, and stem cell phenotype in human glioblastoma in vitro and in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5023. doi:10.1158/1538-7445.AM2017-5023
Abstract 5027: Exome sequencing of cancer-related genes to identify genetic markers for sensitivity to cytotoxic anticancer drugs
Authors: Udagawa Chihiro , Sasaki Yasushi , Suemizu Hiroshi , Ohnishi Yasuyuki , Ohnishi Hiroshi , Tokino Takashi , Zembutsu Hitoshi
Published: July 2017

Although the progress in moving from a one-size-fits-all cytotoxic approach to personalized molecular medicine, majority of the patients with cancer receive chemotherapy with cytotoxic anticancer drugs. Exome sequencing of 409 cancer related genes was conducted using 59 DNAs extracted from human tumor xenografts implanted into nude mice, of which sensitivity to nine cytotoxic anticancer drugs (5-fluorouracil (5FU), Nimustine (ACNU), adriamycin (ADR), cyclophosphamide (CPM), cisplatin (DDP), mitomycin C (MMC), methotrexate (MTX), vincristine (VCR), and vinblastine (VLB)) had been examined. We investigated the relationship between the sensitivities of the xenografts to the nine anticancer drugs and single nucleotide variants (SNVs) by classifying them into three groups according to the allele frequency (≤10%, 10-90%, ≥90%). We further carried out replication study using additional set of 20 xenografts. We also estimated the correlation between the expression levels of the 409 genes and sensitivities to the nine drugs in the above xenografts. In the screening stage using 59 xenografts, three SNVs, which were associated with sensitivity to VCR or MMC, showed P < 0.001. We further carried out a replication study of 596 SNVs showing P < 0.05 in the screening stage using independent samples of 20 xenografts. A combined result of the screening and replication studies suggested possible associations of 35 SNVs with sensitivities to the nine anticancer drugs (Pcombined = 0.0011 - 0.035). A total of 35 SNVs showed possible association with sensitivity to at least one of the nine drugs. Of the 35 SNVs, SNV-1 and SNV-2 in a tumor suppressor gene and a oncogene were commonly associated with sensitivity to two or four anticancer drugs, respectively. These findings provide new insights into precision anticancer therapy for the patients with cancer.

Citation Format: Chihiro Udagawa, Yasushi Sasaki, Hiroshi Suemizu, Yasuyuki Ohnishi, Hiroshi Ohnishi, Takashi Tokino, Hitoshi Zembutsu. Exome sequencing of cancer-related genes to identify genetic markers for sensitivity to cytotoxic anticancer drugs [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5027. doi:10.1158/1538-7445.AM2017-5027
Abstract 5031: Distribution of single nucleotide polymorphisms related to paclitaxel and carboplatin toxicity in ovarian cancer patients
Authors: Cordova Miguel , Bravo Maria L. , Arriagada Isidora , Cumsille Elisa , Quiñones Luis , Bravo Erasmo , Correa Raimundo , Leiva Juan E. , Paredes Cesar , Cuello Mauricio , Ibañez Carolina , Garrido Marcelo , Owen Gareth I.
Published: July 2017

Introduction: Standard first-line treatment for ovarian cancer consists in the combined use of taxanes and platinum, with neuropathies and neutropenia the most frequent and complex adverse drug reactions (ADRs) requiring clinical management. These adverse effects may be related to differing levels of drug transport and metabolism brought about by intrinsic genetic characteristics of the patients. Single nucleotide polymorphisms (SNPs) are now recognized as key factors in the variability of drug response. In a cohort of Chilean ovarian cancer patients we analyzed the frequencies of several SNPs previously reported to be associated with paclitaxel and carboplatin ADRs.

Methods: Blood samples were obtained with informed consent from adult ovarian cancer patients (n = 120). DNA was extracted and SNPs within the ABC transporter and CYP P450 gene families were genotyped. High specificity Taqman probes were used.

Results: Four SNPs associated with risk of ADR within the ABC transporter family showed genotypic frequencies ranging between 0 - 23%. Frequencies for the ADR-associated variants in the CYP P450 family were 4 - 90%. Finally, for the CYP2C8 enzyme, whose function is essential in paclitaxel metabolism, the frequencies of risk-associated SNPs ranged from 2.10% to 13.6%.

Conclusions: SNPs associated with paclitaxel and carboplatin ADRs are highly prevalent in the Chilean population of ovarian cancer patients studied. The identification of these variants may help avoid severe ADRs associated with chemotherapy regimes. Funding: CORFO 13CTI21526-P6 & 13IDL2-18608

Citation Format: Miguel Cordova, Maria L. Bravo, Isidora Arriagada, Elisa Cumsille, Luis Quiñones, Erasmo Bravo, Raimundo Correa, Juan E. Leiva, Cesar Paredes, Mauricio Cuello, Carolina Ibañez, Marcelo Garrido, Gareth I. Owen. Distribution of single nucleotide polymorphisms related to paclitaxel and carboplatin toxicity in ovarian cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5031. doi:10.1158/1538-7445.AM2017-5031
Abstract 504: Quantification of nucleic acid quality in postmortem tissues from a cancer research autopsy program
Authors: Fan Jun , Khanin Raya , Sakamoto Hitomi , Zhong Yi , Michael Chelsea , Pena Derwin , Javier Breanna , Wood Laura , Iacobuzio-Donahue Christine
Published: July 2017

The last decade has seen a marked rise in the use of cancer tissues obtained from research autopsies. Such resources have been invaluable for studying cancer evolution or the mechanisms of therapeutic resistance to targeted therapies. Degradation of biomolecules is a potential challenge to usage of cancer tissues obtained in the post-mortem setting and remains incompletely studied. We analysed the nucleic acid quality in 371 different frozen tissue samples collected from 80 patients who underwent a research autopsy, including eight normal tissue types, primary and metastatic tumors. Our results indicate that RNA integrity number (RIN) of normal tissues decline with the elongation of post-mortem interval (PMI) in a tissue-type specific manner. Unlike normal tissues, the RNA quality of cancer tissues is highly variable with respect to post-mortem interval. The kinetics of DNA damage also has tissue type-specific features. Moreover, while DNA degradation is an indicator of low RNA quality, the converse is not true. Finally, we show that despite RIN values as low as 5.0, robust data can be obtained by RNA sequencing that reliably discriminates expression signatures. Based on this promising pilot data, we are currently identifying samples for multiregion RNA sequencing of pancreatic cancers with divergent morphologies within the primary and/or metastatic sites. Thus far we have screened 554 RNA samples from 10 autopsy cases. These samples represent 198 geographically distinct regions of tumor with duplicate or triplicate RNA extractions. The number of samples per patient ranges from 17 to 86 with an average of 55. Our data shows that high quality RNA can be acquired from cases with long PMI (>48h). While extensive screening of samples is required to identify those with optimal quality, the downstream data produced is of high quality and can support novel hypotheses or validations of experimental data.

Citation Format: Jun Fan, Raya Khanin, Hitomi Sakamoto, Yi Zhong, Chelsea Michael, Derwin Pena, Breanna Javier, Laura Wood, Christine Iacobuzio-Donahue. Quantification of nucleic acid quality in postmortem tissues from a cancer research autopsy program [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 504. doi:10.1158/1538-7445.AM2017-504
Abstract 5040: The plasma and cerebrospinal fluid pharmacokinetics of pegylated liposomal doxorubicin after intravenous administration in non-human primates
Authors: Higham Christine , Murphy Robert , McCully Cynthia , Warren Katherine , Widemann Brigitte
Published: July 2017

Background: Pegylated liposomal doxorubicin (PLD) exhibits altered plasma pharmacokinetics (PK) compared to doxorubicin, with a longer half-life (55 hours), large area under the concentration-time curve (AUC), lower rate of clearance, and markedly smaller volume of distribution. The cerebrospinal fluid (CSF) PK of PLD are unknown. We evaluated the plasma and CSF PK of PLD in a non-human primate (NHP) model.

Methods: PLD was given as single dose (1 mg/kg = low adult recommended dose of 20 mg/m2) intravenously over 60 minutes to 3 NHP with indwelling central venous catheters and central nervous system ventricular reservoirs or lumbar ports. Serial blood and CSF samples were obtained for 96 hours after completion of the infusion. The total doxorubicin concentration (liposome bound + protein bound + free) was quantified with a validated liquid chromatography/tandem mass spectrometry assay (lower limit of quantification plasma=0.29 ng/mL, and CSF=0.06 ng/mL). PK parameters were estimated using non-compartmental methods. CSF penetration was calculated from the AUCCSF:AUCplasma.

Results: PLD was well tolerated. Total doxorubicin plasma concentration time curves were characterized by sustained PLD exposure, comparable to the exposure observed in humans at a similar dose. The terminal elimination phase was not captured. In CSF, doxorubicin was measurable and still present at the last time point in all animals, but the CSF penetration was limited (Table).

Conclusions: Using a sensitive assay, we could quantify doxorubicin in CSF. However, the CSF penetration is limited in NHP with intact blood brain barrier. Our assay analyzed the total doxorubicin concentration in plasma. It is unknown if PLD can penetrate into the CSF, therefore we could not determine if the CSF penetration represents total versus free.

Plasma and CSF PK of pegylated liposomal doxorubicin in NHPAnimalCmax Plasma(ng/mL)Tmax Plasma(h)AUC0-96h Plasma(ng*h/mL)Cmax CSF (ng/mL)Tmax CSF (h)AUC0-96h CSF (ng*h/mL)CSF Penetration (%)19396487.24E+051.84524.210.3323044901.76E+060.71618.750.113374670.081.91E+063.251036.410.2Mean25770161.46E+061.93726.460.21

Citation Format: Christine Higham, Robert Murphy, Cynthia McCully, Katherine Warren, Brigitte Widemann. The plasma and cerebrospinal fluid pharmacokinetics of pegylated liposomal doxorubicin after intravenous administration in non-human primates [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5040. doi:10.1158/1538-7445.AM2017-5040
Abstract 5041: Translational pharmacokinetic-pharmacodynamic xenograft model for TAK-931, a small molecule cell division cycle 7 (CDC7) kinase inhibitor
Authors: Locuson Charles , Patel Mayank , Ohashi Akihiro , Iwai Kenichi , Nambu Tadahiro , Takeuchi Toshiyuki , Kogame Akifumi , Bowman Douglas , Tirrell Stephen , Niu Huifeng , Xia Cindy
Published: July 2017

TAK-931 is a small molecule inhibitor of the cell division cycle 7 (CDC7) kinase. As a serine/threonine kinase that contributes to DNA replication and the DNA damage response, CDC7 is hypothesized to be a promising cancer drug target. CDC7 inhibition with TAK-931 has demonstrated antiproliferative activity with cancer cell lines and tumor growth inhibition (TGI) in murine ectopic xenograft models. Herein, the analysis of multiple models to characterize pharmacokinetic (PK) and pharmacodynamic (PD) relationships with xenograft TGI is described. TAK-931 treatment-induced TGI was dose schedule-independent and could be described using plasma drug concentrations or tumor PD inhibition. However, the efficacious doses were at least 10-fold higher for the PK-TGI relationship than for the PD-TGI relationship. This discrepancy was used to select a dynamic PK-PD-TGI modeling approach to project the minimal efficacious dose (MED) and minimal biological active dose (MBAD) for TAK-931 due to the large differences in time-concentration profiles predicted for humans versus mice. The Phase I human trial is on-going and will be used to verify the dynamic PK-PD-driven modeling approach for the CDC7 inhibitor.

Citation Format: Charles Locuson, Mayank Patel, Akihiro Ohashi, Kenichi Iwai, Tadahiro Nambu, Toshiyuki Takeuchi, Akifumi Kogame, Douglas Bowman, Stephen Tirrell, Huifeng Niu, Cindy Xia. Translational pharmacokinetic-pharmacodynamic xenograft model for TAK-931, a small molecule cell division cycle 7 (CDC7) kinase inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5041. doi:10.1158/1538-7445.AM2017-5041