bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract LB-208: First-in-class steroidal leukemia inhibitory factor (LIF) inhibitor in targeted cancer therapy
Authors: Nair Hareesh B. , Santhamma Bindu , Viswanadhapa Surya , Nickisch Klaus J.
Published: July 2016

The leukemia inhibitory factor (LIF), an IL-6 family member, is a pleotropic cytokine has been demonstrated as an oncogene and involved in multiple cellular mechanisms during the initiation and progression of various human malignancies. Overexpression of LIF was significantly correlated with advanced tumor stage, larger tumor size and worse relapse free survival rate. In the present study EC330, a novel steroidal LIF inhibitor showed cytotoxicity in various cancer cell lines and NCI-60 cell line panel at low nano-molar range. EC330 blocked formation of colonies in soft agar and inhibited angiogenesis (tube formation) in human umbilical vein endothelial cells. EC330 binds to LIF/LIFR complex by insilico docking studies and reduced the STAT3 phosphorylation in a dose dependent manner through blocking LIF-JAK-STAT signaling. EC330 showed marked specificity in MCF-7 cells overexpressing LIF verses MCF-7 cells. The compound further showed cytoskeletal disruption and targeting cancer associated fibroblasts (CAFs). EC330 treatment (0.5 and 2.5mg/kg) dose dependently reduced tumor burden in ovarian (IGROV-1) and triple negative breast cancer (MDA-MB-231) cell xenografted mouse models. These findings establish EC330 as a novel LIF inhibitor having targeted therapeutic perspectives for patients with aggressive primary tumors. LIF targeting may result in the blockade of cancer fibroblast associated pro invasive tumor microenvironment in regular as well as therapy resistant tumors.

Citation Format: Hareesh B. Nair, Bindu Santhamma, Surya Viswanadhapa, Klaus J. Nickisch. First-in-class steroidal leukemia inhibitory factor (LIF) inhibitor in targeted cancer therapy. [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 LB-208.
Abstract LB-231: An optide (optimized knottin-peptide) that inhibits tumor cell growth In vitro and accumulates in sarcoma flank tumors in vivo
Authors: Sottero Theo , Girard Emily J. , Correnti Colin , Stroud Mark R. , Kier Brandon L. , Mhyre Andrew J. , Olson James
Published: July 2016

Antibody-drug conjugates (ADCs) have been FDA approved for the targeted delivery of chemotherapy to cancer. However, ADCs are limited for solid tumors and brain cancer by their poor penetration and inability to cross the blood-brain-barrier. A number of groups have shown that cystine-knot peptides (knottins) can be modified in ways that allow them to target cancer cells. Our lab demonstrated that an optide (optimized knottin-peptides) conjugate such as chlorotoxin-Cy5.5 are able to accumulate throughout tumors and cross an intact blood-brain barrier. However, chlorotoxin-Cy5.5 accumulates in mouse liver - a potential liability if used as a peptide-drug conjugate. We sought to identify a novel peptide that is capable of delivering chemotherapy selectively to tumor cells in vitro and in vivo.

Our group has developed a mammalian protein expression system that is able to produce >20mg scale, endotoxin-free knottins and can rapidly generate variants of those peptides. We went in vivo to investigate if there was selective accumulation of our novel peptide-dye conjugates in sarcoma flank xenografts. Mice were injected intravenously with conjugate and accumulation was quantified in a number of tissues using IVIS imaging. We identified a novel peptide that accumulated in sarcoma flank tumors >10-fold relative to liver. We tested the ability of this peptide to deliver cytotoxic chemotherapy in vitro as a peptide-drug conjugate. We identified a novel conjugate capable of efficiently inhibiting the growth of a number of tumor cell lines in vitro. We tested the ability of various endocytosis inhibitors to prevent the uptake of this peptide and showed that inhibitors of GPI-anchored protein endocytosis prevented this accumulation. To verify tumor accumulation in preparation for efficacy studies we tracked the distribution of a radiolabeled form of the peptide in a whole body autoradiography model and observed sustained tumor uptake.

Our novel peptide-conjugate is able to potently inhibit the growth of a number of tumor cell lines in vitro and the endocytosis of GPI-anchored proteins is involved in this accumulation. Additionally, this peptide accumulates in tumor tissue in vivo. Optide-drug conjugates may offer enhanced tumor penetration over antibody-drug conjugates and therefore increase the therapeutic index in delivering cytotoxic chemotherapy.

Citation Format: Theo Sottero, Emily J. Girard, Colin Correnti, Mark R. Stroud, Brandon L. Kier, Andrew J. Mhyre, James Olson. An optide (optimized knottin-peptide) that inhibits tumor cell growth In vitro and accumulates in sarcoma flank tumors in vivo. [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 LB-231.
Abstract LB-237: BMS-986012, a fully human anti-fucosyl-GM1 antibody has potent in vitro and in vivo antitumor activity in preclinical models of small cell lung cancer
Authors: Chen Bing , Pan Chin , Ponath Paul , Oyasu Miho , Menezes Daniel , Cardarelli Pina
Published: July 2016

Fucosyl-GM1, is a sphingolipid monosialoganglioside and tumor-associated antigen with a high prevalence in human small cell lung cancer (SCLC), while its expression is minimal in most normal tissue. Here, we report results of our preclinical studies with BMS-986012, a novel fully human, non-fucosylated, IgG1 monoclonal antibody that specifically binds to FucGM1. The binding affinity of BMS-986012 was evaluated in Biacore® and cell-based assays. BMS-986012 binds with a high affinity to FucGM1 and demonstrates no significant binding to other closely related gangliosides. The antibody was engineered in a non-fucosylated IgG1 format, resulting in a 40-fold increased affinity for FcγRIIIa (CD16). In in vitro assays, BMS-986012 binds to FucGM1 on cancer cells and activates antibody-dependent cellular cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), and antibody-mediated phagocytosis (ADCP). The antitumor activity of BMS-986012 was profiled in a panel of SCLC lung cancer models in immunodeficient mice with varying FucGM1 target expression levels qualified using immunohistochemistry. Dose-dependent antitumor activity was observed in a panel of SCLC xenograft models with tumor regressions occurring at BMS-986012 doses greater than 0.3 mg/kg against DMS79 tumors. BMS-986012 efficacy generally correlated with FucGM1 target expression in tumor models. In mice, the antibody was well tolerated, with no adverse events observed in long term efficacy studies. Preclinical studies also explored combinations of BMS-986012 with standard-of-care (SOC) chemotherapeutics, including cisplatin, etoposide, topotecan and irinotecan. Combination therapy of BMS-986012 with SOC resulted in significantly enhanced antitumor activity compared to monotherapy. Finally, studies conducted with BMS-986012 in combination with anti-CD137 antibody resulted in significant improvement in efficacy. These data provide preclinical support for evaluation of BMS-986012 in SCLC. BMS-986012 is currently in a phase I trial.

Citation Format: Bing Chen, Chin Pan, Paul Ponath, Miho Oyasu, Daniel Menezes, Pina Cardarelli. BMS-986012, a fully human anti-fucosyl-GM1 antibody has potent in vitro and in vivo antitumor activity in preclinical models of small cell lung 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 LB-237.
Abstract LB-253: Control of tumor growth in vivo by a synthetic multi-antigen DNA immune therapy for prostate cancer
Authors: Ferraro Bernadette , Walters Jewell N. , Reuschel Emma L. , Balakrishnan Amritha , Morrow Matthew P. , Khan Amir S. , Sardesai Niranjan Y. , Humeau Laurent M. , Weiner David B.
Published: July 2016

Prostate cancer (PCa) is one of the leading causes of cancer deaths among men with limited treatment options. Accordingly, new approaches, such as immunotherapy, may represent important approaches for PCa treatment. Electroporation (EP) delivered DNA vaccines has recently shown promising results for therapeutic immunotherapy strategies has been limited to single antigen and epitope targets with limited success. We hypothesized that a broader collection of antigens adjuvanted by plasmid encoded IL-12 would bypass immune tolerance and improve the breadth and effectiveness of a PCa immunotherapy approach. We tested this hypothesis in NHP for immune tolerance effects as well as in the highly relevant TRAMP-C2 challenge model. We developed highly optimized DNA vectors encoding consensus antigens for important PCa targets prostate-specific antigen (SynCon PSA), prostate-specific membrane antigen (SynCon PSMA), and human six-transmembrane epithelial antigen of the prostate (STEAP). In mice the vaccines demonstrated potent IFNγ production by ELISpot (2740 SFU) and robust immune responses in the CD4+ (0.53%) and CD8+ (3.0%) T cell compartments. Further, sera from immunized mice reacted in ELISA with relevant targets and specifically stained LNCaP cells, a human PCa cell line, as well as human PCa tumor sections, supporting that the vaccine antigens induced relevant antibody responses. Vaccination of Rhesus Macaques, which share greater than 98% identity with humans, showed robust anti-PSA, PSMA and STEAP IFNγ production (612 SFU), potential for cytotoxic T cell function, and antigen specific seroconversion supporting the ability of these constructs to break tolerance. The therapeutic potential of PSMA, STEAP, and the combination of PSMA and STEAP, alone or with the molecular adjuvant IL-12, was evaluated in mice in the TRAMP-C2 tumor model. Alone, PSMA, STEAP or PSMA+STEAP demonstrated prolonged survival and a modest impact on tumor growth. However, the combination of synthetic vaccine antigens with IL-12 resulted in 100% efficacy in treatment and clearance of tumors resulting in 100% survival. These data support further study of this novel immune therapy of PCa.

Citation Format: Bernadette Ferraro, Jewell N. Walters, Emma L. Reuschel, Amritha Balakrishnan, Matthew P. Morrow, Amir S. Khan, Niranjan Y. Sardesai, Laurent M. Humeau, David B. Weiner. Control of tumor growth in vivo by a synthetic multi-antigen DNA immune therapy for prostate 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 LB-253.
Abstract LB-271: Targeting fatty acid metabolism regulates the immunosuppressive activity of myeloid-derived suppressor cells
Authors: Al-Khami Amir A. , Hossain Fokhrul , Wyczechowska Dorota , Zheng Liqin , Rodriguez Paulo , Ochoa Augusto C.
Published: July 2016

Myeloid-derived suppressor cells (MDSC) play a major role in the immune defects associated with cancer. Although several mechanisms have been suggested as critical for MDSC-induced T cell suppression, there are no current therapies to block the accumulation and/or function of MDSC. Recent studies have highlighted the role of specific energy metabolic pathways in the activation and function of immune cells. However, the metabolic programs of tumor-associated MDSC (T-MDSC) remain unknown. Herein, we found that T-MDSC, but not splenic MDSC or normal myeloid cells, activated fatty acid oxidation (FAO). T-MDSC increased mitochondrial mass and function, key FAO enzymes, and oxygen consumption rate. Of interest, Inhibition of FAO blocked the immunosuppressive mechanisms and functions in T-MDSC and decreased their production of immunosuppressive cytokines. FAO inhibition also resulted in a T cell-dependent decrease in tumor growth and synergized with low-dose chemotherapy and cellular immunotherapy. Furthermore, targeting fatty acid uptake decreased the regulatory activity of T-MDSC. Human MDSC exhibited similar metabolic characteristics. These data support the possibility of targeting fatty acid metabolism as a novel approach to block MDSC and enhance cancer therapy.

Citation Format: Amir A. Al-Khami, Fokhrul Hossain, Dorota Wyczechowska, Liqin Zheng, Paulo Rodriguez, Augusto C. Ochoa. Targeting fatty acid metabolism regulates the immunosuppressive activity of myeloid-derived suppressor cells. [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 LB-271.
Abstract LB-275: Single cell analysis identified LY6D as a novel marker of castration-resistant multipotent luminal progenitors
Authors: Linn Douglas E. , Barros-Silva João , Guo Guoji , Brown Michael , Ashton Garry , Clarke Noel W. , Yuan Guo-Cheng , Orkin Stuart H. , Baena Esther , Li Zhe
Published: July 2016

The cellular origin of castration-resistant prostate cancer (CRPC) remains largely unsolved. We compared single-cell expression profiles of prostate cells sorted from hormone-naïve and castrated mice. Our single-cell analysis reveals that the prostate luminal lineage is highly heterogeneous. A subset of prostate cells in the luminal lineage characterized by high expression levels of luminal lineage markers including cytokeratin 8 (Krt8) and androgen receptor (Ar) genes, as well as prostate stem/progenitor marker genes (e.g., Trop2/Tacstd2, Sca1/Ly6a), and intermediate levels of basal genes (e.g. Trp63, Krt5), is enriched upon castration. We validated LY6D as a novel marker of castration-resistant (CR) multipotent luminal progenitor. Organoid culture revealed that LY6D+ prostate cells, including LY6D+ prostate luminal cells, were enriched with multipotent organoid-forming cells under androgen-deprivation. Lineage-tracing using Krt8-CreER mice revealed that in wild-type mice, LY6D+ CR luminal cells appeared to produce LY6D- luminal cells upon regeneration; however, when under the Pten-loss background, LY6D+ Pten-null luminal cells gave rise to LY6D+ luminal cancer cells. Furthermore, upon induced loss of Pten, prostate cancers originating from Krt8+ CR luminal cells were LY6D+ high-grade and were more advanced than those originating from hormone-naïve luminal cells. Lastly, in prostate cancer patients, LY6D amplification/upregulation correlates with advanced disease. Overall, our results uncover the luminal lineage heterogeneity and identify LY6D as a novel tumor-initiating cell marker of CRPC.

Citation Format: Douglas E. Linn, João Barros-Silva, Guoji Guo, Michael Brown, Garry Ashton, Noel W. Clarke, Guo-Cheng Yuan, Stuart H. Orkin, Esther Baena, Zhe Li. Single cell analysis identified LY6D as a novel marker of castration-resistant multipotent luminal progenitors. [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 LB-275.
Abstract LB-277: Induction chemotherapy induces enrichment of leukemic stem cells in PDX models of acute myeloid leukemia
Authors: Zhang Cathy C. , Yan Zhengming , Pascual Bernadette , Huang Stephen , Zong Qing , Elliot Mark , Lappin Patrick
Published: July 2016

Human leukemic stem cells may be one of the leading causes for resistance or treatment failure in acute myeloid leukemia patients. To gain insights into the mechanisms underlying chemo-resistance of AML disease, we evaluated the biomarkers and the pharmacological properties of minimal residual disease post induction therapy. The PDX models were established by iv injecting acute myeloid leukemia patient cells in NOD/SCID/Il2rg(-/-) mice (NSG). The disease progression was tracked by the AML counts in peripheral blood and bone marrow via FACS analysis. In the PDX models, daunorubicin/cytarabine (DA) chemotherapy showed early antileukemic efficacy through apoptosis induction and antiproliferation. However, treatment showed minimal survival benefits and all treated leukemic mice relapsed due to the minimal residual disease (MRD). FACS analysis showed that DA therapy induced enrichment of CD34+ and CLL1+/CD117- cells in the MRD of the BM0407 and BM2407 AML PDX models, respectively. Subsequently, we performed self-renewal functional test by in vivo reimplantation of sorted CD34+ and CLL1+/CD117- cells. The limiting delusion analysis showed that the chemo- resistant CD34+ and CLL1+/CD117- cells are much more tumorigenic than their counterpart CD34- and CLL1+/CD117+ cells, respectively. This work provides insights into the mechanism of chemo-resistance and helps identifying new strategies to improve AML therapy.

Citation Format: Cathy C. Zhang, Zhengming Yan, Bernadette Pascual, Stephen Huang, Qing Zong, Mark Elliot, Patrick Lappin. Induction chemotherapy induces enrichment of leukemic stem cells in PDX models of acute myeloid leukemia. [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 LB-277.
Abstract LB-290: UCSC TumorMap: Exploring cancer signatures on an interactive dynamic landscape
Authors: Newton Yulia , Novak Adam , Swatlowski Teresa , Chopra Sahil , Salama Sofie , Morozova Olena , Haussler David , Stuart Joshua
Published: July 2016

Cancer is caused by accumulated changes in a cell's DNA sequence that disrupt the regulation of genetic networks. Mutation type, cell of origin, and tissue microenvironment all influence the initiation and progression of disease. The Cancer Genome Atlas (TCGA) catalogues the molecular changes of thousands of tumor samples of various tumor types using different data modalities including genomic, transcriptomic, proteomic, and epigenomic views. The goal is to find similarities amongst cancers of different tissues and to reveal clinically-relevant subtypes sharing common molecular abnormalities. While various analyses for interpreting these rich datasets exist, few methods are available to enable intuitive global overviews of these rich compendia. There is a need for methods that can tap the statistical power of large cohorts, to aid in analysis of smaller cohorts and of individual patient samples. Patterns present in many tumors may reveal driving genomic aberrations and pathway signatures that inform therapy. Here, we present a TumorMap, a tool that generates a map of cancer samples for interactive exploration, data overlay visualization, and statistical analysis. TumorMap arranges samples on a hexagonal 2-dimensional grid based on sample similarity. Different maps can be made for each distinct platform of data. Herein we demonstrate the utility of TumorMap for revealing commonalities between cancers of different tissue types, and its ability to aid in pan-cancer hypothesis generation. TumorMap maps for various cancer cohorts are available for free online at http://tumormap.ucsc.edu.

Citation Format: Yulia Newton, Adam Novak, Teresa Swatlowski, Sahil Chopra, Sofie Salama, Olena Morozova, David Haussler, Joshua Stuart. UCSC TumorMap: Exploring cancer signatures on an interactive dynamic landscape. [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 LB-290.
Abstract LB-306: Molecular mechanisms of trastuzumab-mediated cardiomyopathy: Implications of autophagy in trastuzumab-induced cardiotoxicity
Authors: Mohan Nishant , Shen Yi , Wu Wen J.
Published: July 2016

Trastuzumab is a humanized monoclonal antibody directed against the extracellular domain IV of human epidermal growth factor receptor 2 (HER2) and approved for the treatment of HER-2 positive breast cancer and gastric cancer. Trastuzumab therapy is associated with considerable cardiotoxicity, the mechanism of which remains unclear. Dysregulation of autophagy has been implicated in various cardiovascular diseases. In this investigation, we explored a novel mechanism by which trastuzumab dysregulates HER2 signaling and impairs basal autophagic process in human primary cardiomyocytes. Specifically, trastuzumab treatment leads to the phosphorylation of HER1-Y845 and HER2-Y1248 and the activation of Erk. This in turn results in up-regulation of mTOR/Ulk1 pathway and subsequently inhibition of autophagy in primary cardiomyocytes, by downregulating LC3I/II and increase in p62. We further demonstrate that trastuzumab-mediated inhibition of autophagy resulted in the increased production of reactive oxygen species (ROS) in cardiomyocytes. Pertuzumab, another anti-HER2 therapeutic mAb binding to HER2 domain II, fails to modulate HER2 signaling and is unable to influence autophagy in cardiomyocytes. This study provides novel mechanistic insights into trastuzumab-induced cardiotoxicity, which may assist in formulating novel approaches for clinical management of trastuzumab-induced cardiomyopathy.

Citation Format: Nishant Mohan, Yi Shen, Wen J. Wu. Molecular mechanisms of trastuzumab-mediated cardiomyopathy: Implications of autophagy in trastuzumab-induced cardiotoxicity. [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 LB-306.
Abstract LB-311: Elevated kynureninase protein expression is associated with KEAP1 mutant non-small cell lung cancer and is predictive of poor overall survival
Authors: Fahrmann Johannes F. , Dennison Jennifer , Murage Eunice , Wang Hong , Ostrin Edwin J. , Taguchi Ayumu , Hanash Samir
Published: July 2016

Purpose: To identify signatures related to tryptophan metabolism independent of indoleamine 2,3-dioxygenase (IDO) that are predictive of tumor behavior.

Introduction: Recent evidence has pointed to the importance of tryptophan catabolites on immune suppression and promotion of tumor growth. IDO1 is a rate-limiting enzyme in tryptophan catabolism currently targeted in clinical trials. Tryptophan catabolism can occur in IDO-negative tumors and resulting metabolites may have immunosuppressive and potential autocrine functions. Our late breaking finding is that we have uncovered signatures related to tryptophan metabolism independent of IDO that impact clinical outcome in NSCLC.

Experimental Procedures: We initially carried out integrated genomic and proteomic profiling of 114 cancer cell lines. Small interfering RNA transfection experiments were used to evaluate the effect of KYNU knockdown on cell viability. TCGA data was analyzed to determine clinical relevance.

Results: We identified kynureninase (KYNU), an enzyme involved in tryptophan metabolism that mediates formation of anthranilate and 3-hydroxyanthranilate, as uniquely overexpressed at the RNA and protein levels in NSCLC compared to other cancer types. These findings were not conserved for IDO or tryptophan 2,3-dioxygenase (TDO2), rate-limiting enzymes in tryptophan metabolism. Knockdown of KYNU reduced cell viability of NSCLC cell lines tested. Upregulation of KYNU was highly associated with KEAP1 mutational status and positively correlated with numerous Nrf-2 regulated-genes at both the protein and mRNA level. These findings were confirmed using TCGA data. KYNU mRNA levels predicted worse outcomes in stage II and III NSCLC adenocarcinoma and squamous cell carcinoma in TCGA cohorts independently of other covariates (P = : 0.008).

Conclusion: We have uncovered a unique signature in NSCLC reflective of aberrant tryptophan metabolism mediated by elevated KYNU but not IDO/TDO2. KYNU expression is highly associated with KEAP1 mutational status. High KYNU mRNA levels was predictive of worse clinical outcomes in NSCLC.

Citation Format: Johannes F. Fahrmann, Jennifer Dennison, Eunice Murage, Hong Wang, Edwin J. Ostrin, Ayumu Taguchi, Samir Hanash. Elevated kynureninase protein expression is associated with KEAP1 mutant non-small cell lung cancer and is predictive of poor overall survival. [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 LB-311.
Abstract LB-315: Bone marrow adipocytes alter the metabolic phenotype of metastatic prostate cancer cells through the activation of HIF-1a
Authors: Diedrich Jonathan , Rajagurubandara Erandi , Herroon Mackenzie , Podgorski Izabela
Published: July 2016

Bone is a preferential site of metastasis from prostate cancer (PCa). Age and obesity, conditions that increase adipocyte numbers in bone marrow, are risk factors for skeletal metastases from PCa. Research in our laboratory focuses on understanding the interactions between adipocytes and tumor cells that have infiltrated the bone marrow. Specifically, we are examining how the secretion, transport, and uptake of adipocyte-supplied factors promote metastatic progression in bone. We have previously shown that bone marrow adipocytes enhance a glycolytic phenotype in PCa cells through paracrine activation of glycolytic enzymes GLUT1, HK2, PDK1, ENO2, and LDHa at both the mRNA and protein levels. This correlated with an increase in glycolytic activity as measured by higher levels of lactate secretion and decreases in oxidative phosphorylation, indicative of an enhanced Warburg-like metabolic signature. We then assessed HIF-1a activity through mRNA analysis of HIF-1a target genes carbonic anhydrase 9 (CA9) and vascular endothelial growth factor (VEGF). We found that CA9 and VEGF had elevated expression levels in tumor cells exposed to adipocytes, indicative of enhanced HIF-1a activity. Notably, PCa cells exposed to bone marrow adipocytes had significantly enhanced presence of HIF-1a in the nucleus, result further confirming HIF-1α, activation in tumor cells exposed to marrow adipocytes. Hypoxia chamber experiments revealed that these effects were observable regardless of the presence or absence of oxygen, indicating the presence of oxygen-independent HIF-1a signaling or a state of pseudohypoxia in tumor cells. These results were further validated in multiple in vitro cell culture and in vivo mouse models, where an increased production of both glycolytic genes and HIF-1α target genes was shown to correlate with marrow adiposity. Our overall hypothesis is that bone marrow adipocyte-supplied lipids within the bone microenvironment cause HIF-1a activation and metabolic switch to glycolysis in metastatic PCa cells in bone, leading to their increased aggressiveness and resistance to therapy.

Citation Format: Jonathan Diedrich, Erandi Rajagurubandara, Mackenzie Herroon, Izabela Podgorski. Bone marrow adipocytes alter the metabolic phenotype of metastatic prostate cancer cells through the activation of HIF-1a. [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 LB-315.
Abstract LB-375: Childhood body size at age 13 years and associations with ovarian cancer in adult life
Authors: Aarestrup Julie , Gamborg Michael , Wentzensen Nicolas , Ulrich Lian G. , Sørensen Thorkild IA , Baker Jennifer L.
Published: July 2016

Background: Among women, body mass index (BMI; kg/m2) and attained height are positively associated with ovarian cancer. Few studies have, however, investigated associations with childhood body size. As such, it remains largely unknown if it is body size development in early life or adult life that contributes to these associations. Therefore, we examined if childhood BMI and height at age 13 years were associated with ovarian cancer in adult life.

Methods: Individuals were girls in the Copenhagen School Health Records Register who were born between 1930 and1989 and had available measures of height and weight at age 13 years. BMI and height z-scores were calculated from an internal age-specific reference. Via a personal identification number, individuals were followed up for ovarian cancer diagnosis by linkage to the Danish Cancer Registry. Cox proportional hazard regressions were performed and stratified by birth cohort.

Results: Among the included 137,416 girls, 1048 cases of ovarian cancer occurred during 5.2 million person-years of follow-up with a median age of diagnosis of 57 years (range: 19-83 years). BMI tended to be non-linearly associated with ovarian cancer such that only the heaviest girls had positive associations with ovarian cancer. Compared with a 13-year-old girl of average-size (BMI z-score = 0, corresponding to a weight of 45 kg and a height of 157 cm), an equally tall girl who was at least 9 kg heavier (corresponding to a BMI z-score >1.28) had a hazard ratio (HR) for ovarian cancer of 1.33 (95% confidence interval [CI]: 1.08-1.63). In analyses adjusted for childhood height, the association was only marginally attenuated (HR = 1.30, 95% CI: 1.06-1.60). Childhood height was positively and statistically significantly associated with ovarian cancer. At age 13 years, per height z-score (corresponding to approximately 7 cm), the HR for ovarian cancer was 1.07 (95% CI: 1.01-1.14).

Conclusion: Body size in early life was associated with ovarian malignancies later in life suggesting that childhood height and BMI might impact if women are later diagnosed with ovarian cancer. As ovarian cancers vary widely in their etiologies, associations with childhood body size may differ depending on the tumor type, which will be investigated.

Citation Format: Julie Aarestrup, Michael Gamborg, Nicolas Wentzensen, Lian G. Ulrich, Thorkild IA Sørensen, Jennifer L. Baker. Childhood body size at age 13 years and associations with ovarian cancer in adult life. [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 LB-375.
Abstract LB-376: Hormone therapy use and DNA methylation in breast tissue
Authors: Harlid Sophia , Xu Zongli , Kirk Erin L. , Wilson Lauren E. , Troester Melissa A. , Taylor Jack A.
Published: July 2016

The association between use of hormone therapy (HT) and breast cancer risk has been consistently replicated in epidemiologic studies, but the biological effects of HT on breast tissue are poorly understood. We hypothesized that postmenopausal exposure to HT leads to changes in DNA methylation in breast tissue. We used fresh frozen samples from the Normal Breast Study (NBS), a hospital based study conducted between 2009 and 2013 at the University of North Carolina in Chapel Hill. Women undergoing breast surgery for reduction mammoplasty, prophylactic resection, or tumor resection donated samples of histologically normal-appearing breast tissue. Out of 474 enrolled participants 106 reported ever using hormone therapy, 37 of which had used it within one year of surgery (classified as current users) and 17 of which had used HT within 1-5 years prior to surgery (classified as recent users). Current and recent users were compared with 36 age frequency-matched controls that had never used HT. Frozen tissue DNA samples from these 90 women were evaluated using the Illumina HumanMethylation450 BeadChip. Genome wide DNA methylation data was analyzed using the reference-free cell mixture method to test for associations between HT-use and the methylation level at each CpG site. In the model we adjusted for SVA derived surrogate variables, to control for unobserved confounders, and multiple comparisons using the false discovery rate (FDR). Although methylation differences between current and never users were small in magnitude (β<0.05), 290 CpGs were significantly differentially methylated (FDR, q<0.05). The top CpG was located in an intronic region of the DDX10 gene (p = 7.9E-10, q = 0.0003), previously known to be translocated in estrogen receptor-negative (ER-) breast cancer. Our results extend the evidence base for hormonally derived epigenetic changes in breast tissue.

Citation Format: Sophia Harlid, Zongli Xu, Erin L. Kirk, Lauren E. Wilson, Melissa A. Troester, Jack A. Taylor. Hormone therapy use and DNA methylation in breast tissue. [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 LB-376.
Abstract PL02-02: Transcriptional regulation by the MAX-like protein MLX is required for adaptive metabolic responses in development and tumorigenesis
Authors: Carroll Patrick A. , Cheng Pei-Feng , Muller Charles H. , Hunt Liam , Demontis Fabio , Ayer Don E. , Eisenman Robert N.
Published: July 2016

The MYC transcription factor, together with its obligate dimerization partner, MAX, regulates widespread gene expression and is implicated in the etiology of a broad spectrum of cancers. MYC and MAX are members of the MAX-MLX superfamily of bHLHZ transcription factors (which includes MYC, MAX, MXD, MLX, and MONDO/ChREBP). Members of this highly conserved family respond to environmental cues to modulate gene expression programs and control cellular fate. We recently showed that metabolic reprogramming and survival in MYC-driven cancer cells is coordinately regulated by MYC-MAX and MONDOA-MLX. While knockdown of MONDOA or MLX affected multiple metabolic pathways in MYC-induced tumors, we found that decreased fatty acid synthesis primarily accounted for the loss of viability (Carroll et al. Cancer Cell 27:271, 2015)

To explore the physiological role of the MLX branch of the MAX-MLX network we generated mice with targeted deletion of Mlx. Mlx null mice appeared to develop normally; however, we found that Mlx null males are infertile, with strikingly diminished sperm production, viability, and motility. MondoA knockout mice exhibited a similar phenotype. By employing tissue-specific Cre-mediated deletion of Mlx, we uncovered metabolic defects in both Sertoli cells as well as germ cells, including loss of lipogenic enzymes and altered lipid content. Moreover, we found that human male germ cell tumors (MGCTs) overexpress MAX-MLX network proteins and undergo apoptosis upon loss of MONDOA/MLX. Importantly, the same metabolic pathways shown to be crucial for survival of neuroblastoma are also required for survival of MGCTs.

Furthermore. we have uncovered a critical role for MLX in myokine production required for myoblast fusion in vitro. Moreover, mice bearing homozygous deletion of Mlx fail to regenerate muscle following cardiotoxin treatment (Hunt et al. Genes Dev. 29:2475, 2015). Taken together, our studies suggest a critical role for the MLX arm of the MAX-MLX network in adaptive metabolic responses in tumorigenesis and development.

Funding: NIH grants CA57138 (to RNE) and GM055668 (to DEA); ALSAC of St. Jude Children's Research Hospital, the Ellison Medical Foundation, the Glenn Foundation for Medical Research, and the American Federation for Aging Research (AFAR) (to FD).

Citation Format: Patrick A. Carroll, Pei-Feng Cheng, Charles H. Muller, Liam Hunt, Fabio Demontis, Don E. Ayer, Robert N. Eisenman. Transcriptional regulation by the MAX-like protein MLX is required for adaptive metabolic responses in development and tumorigenesis. [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 PL02-02.
Abstract SY03-01: Macrophage PI3Kgamma drives cancer immune suppression
Authors: Varner Judith A.
Published: July 2016

Innate immune cells can switch from a proinflammatory state that defends against pathogens and to an anti-inflammatory state that repairs damaged tissue. Proinflammatory myeloid cells activate cytotoxic T cells to eliminate pathogens, but anti-inflammatory myeloid cells inhibit T-cell-mediated immunity, stimulate angiogenesis, and stimulate fibrosis, all of which promote tumor progression. The predominant isoform of PI(3)Kinase in myeloid cells, PI3Kgamma, controls this switch between immune stimulation and immune suppression during inflammation and cancer. Myeloid cell PI3Kgamma and its effectors Akt1, mTor, and S6Kinase stimulate C/EBPbeta-dependent expression of immunosuppressive factors, including Arginase and TGFbeta, while also suppressing NFkappaB-dependent expression of proinflammatory cytokines such as IL12 and IFNgamma, thereby inducing tumor immune suppression and consequent tumor growth and metastasis.

In contrast, inhibition of PI3Kgamma activity by genetic or pharmacological means suppresses C/EPBbeta-mediated transcription of anti-inflammatory factors and stimulates NFkappaB-mediated transcription of the proinflammatory cytokines IL12 and IFNgamma, thereby restoring CD8+ T-cell-dependent cytotoxicity that inhibits tumor growth and metastasis. Therefore, inhibitory targeting of PI3Kgamma indirectly restores cytotoxic T-cell immune responses that elicit tumor suppression without unwanted side effects. Our studies highlight the strong therapeutic potential of targeting this kinase to control inflammation and cancer.

This work was supported by grants to JAV from the NIH (5R01CA126820), the Landon Foundation-AACR (12-60-27-VARN), the Lustgarten Foundation for Pancreatic Research and the Whitworth Foundation for Cancer Research.

Citation Format: Judith A. Varner. Macrophage PI3Kgamma drives cancer immune suppression. [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 SY03-01.
Abstract SY08-02: Normal and neoplastic stem cells
Authors: Weissman Irving L.
Published: July 2016

The transition from single cell species to multicellular organisms led to organ and tissue development. The development and maintenance of organs/tissues in multicellular organisms has resulted in the emergence of specialized cells that self-renew as well as differentiate; these rare cells are stem cells. Following embryonic development, most of our tissues and organs are continuously regenerated from tissue/organ specific stem cells. The principal property that distinguishes such stem cells from their daughter cells is self-renewal; when stem cells divide they give rise to stem cells (by self-renewal) and progenitors (by differentiation). In most tissues only the primitive stem cells self-renew. Even within a particular tissue, stem cells may be diverse, and subject to stem cell competition for their niche. We have documented both germline stem cell and somatic stem cell competition in species as diverse as colonial protochordates and humans. Stem cell isolation and transplantation is the basis for regenerative medicine. Self-renewal is dangerous, and therefore strictly regulated. Poorly regulated self-renewal can lead to the genesis of cancer stem cells, the only self-renewing cells in the cancerous tumor. The Weissman lab has followed the progression from hematopoietic stem cells (HSCs) to myelogenous leukemias. They have found that the developing cancer clones progress at the stage of HSCs, until they become fully malignant. At this point, the “leukemia” stem cell is at a stage of a downstream oligolineage or multilineage progenitor that has evaded programmed cell death and programmed cell removal, while acquiring or keeping self-renewal. In the case of chronic myeloid leukemia, bcr-abl+ HSC clones outcompete normal HSCs in the chronic phase. The transition from the chronic phase to myeloid blast crisis results in the leukemia stem cells appearing in the granulocyte-macrophage progenitor (GMP) stage. While there are many ways to defeat programmed cell death and senescence, there appears to be one dominant method to avoid programmed cell removal—the expression of the cell surface “don't eat me” protein CD47, the ligand for macrophage SIRPα. All cancers tested express CD47 to overcome expression of “eat me” signals such as calreticulin. Antibodies that block the CD47-SIRPα interaction enable phagocytosis and killing of the tumor cells in vitro and in vivo. All tested human solid tumors and lymphomas/leukemias/myelomas express CD47 and are susceptible to phagocytosis in the presence of anti-CD47 blocking antibodies.

Citation Format: Irving L. Weissman. Normal and neoplastic stem cells. [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 SY08-02.
Abstract SY16-03: Targeting Bcl-2 as a therapeutic strategy and predictive biomarker in CLL
Authors: Davids Matthew S.
Published: July 2016

The selective BCL-2 antagonist venetoclax has recently demonstrated striking efficacy in patients with CLL, even those with high risk, refractory disease. This presentation will review the preclinical data that supported exploring BCL-2 inhibition in CLL and the clinical trial results of venetoclax monotherapy in this disease. Tumor lysis syndrome and how this risk can be mitigated will also be discussed. Mitochondrial priming reflects the proximity of a cell to the threshold of apoptosis and can be measured using a functional technique known as BH3 profiling. Data will also be presented which suggest that BH3 profiling may serve as a predictive biomarker of response to venetoclax in CLL, and that the change in priming in response to ex vivo drug treatments may help identify optimal combination partners for venetoclax to inform the design of clinical trials for CLL patients.

Citation Format: Matthew S. Davids. Targeting Bcl-2 as a therapeutic strategy and predictive biomarker in CLL. [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 SY16-03.
Abstract SY20-03: Metastatic latency and immune evasion by cancer stem cells
Authors: Massague Joan
Published: July 2016

Metastasis frequently develops, years after the removal of a primary tumor, from a minority of disseminated cancer cells that survived as latent entities. An improved understanding of the location and survival mechanisms of disseminated cancer cells, and their ability to enter a quiescent state, evade immune surveillance, and retain tumor reinitiating capacity is needed in order to better prevent and treat metastasis. To this end, we developed latency competent cancer cell (LCC) models from early stage human lung and breast carcinoma cell lines and defined the mechanisms that prevent the outgrowth, support the long-term survival, and maintain the tumor-initiating potential of these cells during latent metastasis. LCC cells show stem cell-like characteristics and express Sox transcription factors, which are essential for their survival in host organs under restrictive conditions and for metastatic outgrowth under permissive conditions. Through autocrine suppression of WNT signaling and heightened TGF-β signaling, LCC cells self-impose a slow-cycling state with broad downregulation of NK cell activators. By actively entering quiescence, metastatic stem cells can evade innate immunity to remain latent for extended periods. By persistently reentering the proliferative state, these cells may evolve organ-specific colonization traits to take over the host stroma.

Citation Format: Joan Massague. Metastatic latency and immune evasion by cancer stem cells. [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 SY20-03.
Abstract SY43-01: Precision cancer medicine using BH3 profiling
Authors: Letai Anthony G.
Published: July 2016

The job of precision medicine is to match the right patient to the right drug(s). While the term “precision medicine” is often considered synonymous with “cancer genomics,” -omics approaches have thus far enjoyed only inconsistent success in assigning therapy to patients, despite the abundance of data such approaches generate. We favor functional approaches that allow for perturbation of the cancer cells of interest. BH3 profiling can measure the state of the apoptotic pathway of a cancer cell before and after brief exposures to drugs. By identifying drugs that enhance apoptotic signaling in brief ex vivo exposures, we can identify agents that are active in vivo. An advantage to dynamic BH3 profiling is that its measurements can be made in less than 24 hours, removing the requirement for longer term ex vivo culture that has typically proved a major stumbling block for ex vivo approaches.

Citation Format: Anthony G. Letai. Precision cancer medicine using BH3 profiling. [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 SY43-01.
Induction of PSMA and Internalization of an Anti-PSMA mAb in the Vascular Compartment
Authors: Nguyen Daniel P. , Xiong Peter L. , Liu He , Pan Samuel , Leconet Wilhem , Navarro Vincent , Guo Ming , Moy Jonathan , Kim Sae , Ramirez-Fort Marigdalia K. , Batra Jaspreet S. , Bander Neil H.
Published: July 2016

Angiogenesis is critical for tumor growth and survival and involves interactions between cancer and endothelial cells. Prostate-specific membrane antigen (PSMA/FOLH1) is expressed in the neovasculature of several types of cancer. However, the study of neovascular PSMA expression has been impeded as human umbilical vein endothelial cell (HUVEC) cultures are PSMA-negative and both tumor xenografts and patient-derived xenograft (PDX) models are not known to express PSMA in their vasculature. Therefore, PSMA expression was examined in HUVECs, in vitro and in vivo, and we tested the hypothesis that cancer cell–HUVEC crosstalk could induce the expression of PSMA in HUVECs. Interestingly, conditioned media from several cancer cell lines induced PSMA expression in HUVECs, in vitro, and these lines induced PSMA, in vivo, in a HUVEC coimplantation mouse model. Furthermore, HUVECs in which PSMA expression was induced were able to internalize J591, a mAb that recognizes an extracellular epitope of PSMA as well as nanoparticles bearing a PSMA-binding ligand/inhibitor. These findings offer new avenues to study the molecular mechanism responsible for tumor cell induction of PSMA in neovasculature as well as the biological role of PSMA in neovasculature. Finally, these data suggest that PSMA-targeted therapies could synergize with antiangiogenic and/or other antitumor agents and provide a promising model system to test therapeutic modalities that target PSMA in these settings.

Implications: Cancer cells are able to induce PSMA expression in HUVECs, in vitro and in vivo, allowing internalization of PSMA-specific mAbs and nanoparticles bearing a PSMA-binding ligand/inhibitor. Mol Cancer Res; 14(11); 1045–53. ©2016 AACR.