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Inhibitors that block the programmed cell death-1 (PD-1) pathway can potentiate endogenous antitumor immunity and have markedly improved cancer survival rates across a broad range of indications. However, these treatments work for only a minority of patients. The efficacy of anti-PD-1 inhibitors may be extended by cytokines, however, the incorporation of cytokines into therapeutic regimens has significant challenges. In their natural form when administered as recombinant proteins, cytokine treatments are often associated with low response rates. Most cytokines have a short half-life which limits their exposure and efficacy. In addition, cytokines can activate counterregulatory pathways, in the case of immune-potentiating cytokines this can lead to immune suppression and thereby diminish their potential efficacy. Improving the drug-like properties of natural cytokines using protein engineering can yield synthetic cytokines with improved bioavailability and tissue targeting, allowing for enhanced efficacy and reduced off-target effects. Using structure guided engineering we have designed a novel class of antibody-cytokine fusion proteins consisting of a PD-1 targeting antibody fused together with an interleukin-21 (IL-21) cytokine mutein. Our bifunctional fusion proteins can block PD-1/programmed death-ligand 1 (PD-L1) interaction whilst simultaneously delivering IL-21 cytokine to PD-1 expressing T cells. Targeted delivery of IL-21 can improve T cell function in a manner that is superior to anti-PD-1 monotherapy. Fusion of engineered IL-21 variants to anti-PD1 antibodies can improve the drug-like properties of IL-21 cytokine leading to improved cytokine serum half-life allowing for less frequent dosing. In addition, we show that targeted delivery of IL-21 can minimize any potential detrimental effect on local antigen-presenting cells. A highly attenuated IL-21 mutein variant (R9E:R76A) fused to a PD-1 antibody provides protection in a humanized mouse model of cancer that is refractory to anti-PD-1 monotherapy. Collectively, our preclinical data demonstrate that this approach may improve upon and extend the utility of anti-PD-1 therapeutics currently in the clinic.

Cancers are often initiated by genetic events that activate proto-oncogenes or inactivate tumor suppressor genes. These events are also critical for sustained tumor cell proliferation and survival, a phenomenon described as oncogene addiction. In addition to this cell intrinsic role, recent evidence indicates that oncogenes also directly regulate immune responses, leading to immunosuppression. Expression of many oncogenes, or loss of tumor suppressors, indeed induces the expression of immune checkpoints including PD-L1, which regulate the immune response. Here, we discuss how oncogenes, and in particular MYC, suppress immune surveillance and how oncogene-targeted therapies may restore the immune response against tumors.

The MYC proto-oncogene is a gene product that coordinates the transcriptional regulation of a multitude of genes that are essential to cellular programs required for normal as well as neoplastic cellular growth and proliferation, including cell cycle, self-renewal, survival, cell growth, metabolism, protein and ribosomal biogenesis, and differentiation. Here, we propose that MYC regulates these programs in a manner that is coordinated with a global influence on the host immune response. MYC had been presumed to contribute to tumorigenesis through tumor cell–intrinsic influences. More recently, MYC expression in tumor cells has been shown to regulate the tumor microenvironment through effects on both innate and adaptive immune effector cells and immune regulatory cytokines. Then, MYC was shown to regulate the expression of the immune checkpoint gene products CD47 and programmed death-ligand 1. Similarly, other oncogenes, which are known to modulate MYC, have been shown to regulate immune checkpoints. Hence, MYC may generally prevent highly proliferative cells from eliciting an immune response. MYC-driven neoplastic cells have coopted this mechanism to bypass immune detection. Thus, MYC inactivation can restore the immune response against a tumor. MYC-induced tumors may be particularly sensitive to immuno-oncology therapeutic interventions.

The MYC oncogene is frequently mutated and overexpressed in human renal cell carcinoma (RCC). However, there have been no studies on the causative role of MYC or any other oncogene in the initiation or maintenance of kidney tumorigenesis. Here, we show through a conditional transgenic mouse model that the MYC oncogene, but not the RAS oncogene, initiates and maintains RCC. Desorption electrospray ionization-mass-spectrometric imaging was used to obtain chemical maps of metabolites and lipids in the mouse RCC samples. Gene expression analysis revealed that the mouse tumors mimicked human RCC. The data suggested that MYC-induced RCC up-regulated the glutaminolytic pathway instead of the glycolytic pathway. The pharmacologic inhibition of glutamine metabolism with bis-2-(5-phenylacetamido-1,2,4-thiadiazol-2-yl)ethyl sulfide impeded MYC-mediated RCC tumor progression. Our studies demonstrate that MYC overexpression causes RCC and points to the inhibition of glutamine metabolism as a potential therapeutic approach for the treatment of this disease.

© 2015 The Authors. We present a detailed response to the critique of "State of the Science of Endocrine Disrupting Chemicals 2012" (UNEP/WHO, 2013) by financial stakeholders, authored by Lamb et al. (2014). Lamb et al.'s claim that UNEP/WHO (2013) does not provide a balanced perspective on endocrine disruption is based on incomplete and misleading quoting of the report through omission of qualifying statements and inaccurate description of study objectives, results and conclusions. Lamb et al. define extremely narrow standards for synthesizing evidence which are then used to dismiss the UNEP/WHO 2013 report as flawed. We show that Lamb et al. misuse conceptual frameworks for assessing causality, especially the Bradford-Hill criteria, by ignoring the fundamental problems that exist with inferring causality from empirical observations. We conclude that Lamb et al.'s attempt of deconstructing the UNEP/WHO (2013) report is not particularly erudite and that their critique is not intended to be convincing to the scientific community, but to confuse the scientific data. Consequently, it promotes misinterpretation of the UNEP/WHO (2013) report by non-specialists, bureaucrats, politicians and other decision makers not intimately familiar with the topic of endocrine disruption and therefore susceptible to false generalizations of bias and subjectivity.

Tumors are genetically complex and can have a multitude of mutations. Consequently, it is surprising that the suppression of a single oncogene can result in rapid and sustained tumor regression, illustrating the concept that cancers are often “oncogene addicted.” The mechanism of oncogene addiction has been presumed to be largely cell autonomous as a consequence of the restoration of normal physiological programs that induce proliferative arrest, apoptosis, differentiation, and/or cellular senescence. Interestingly, it has recently become apparent that upon oncogene inactivation, the immune response is critical in mediating the phenotypic consequences of oncogene addiction. In particular, CD4+ T cells have been suggested to be essential to the remodeling of the tumor microenvironment, including the shut down of host angiogenesis and the induction of cellular senescence in the tumor. However, adaptive and innate immune cells are likely involved. Thus, the effectors of the immune system are not only involved in tumor initiation, tumor progression, and immunosurveillance, but are also involved in the mechanism of tumor regression upon targeted oncogene inactivation. Hence, oncogene inactivation may be an effective therapeutic approach because it both reverses the neoplastic state within a cancer cell and reactivates the host immune response that remodels the tumor microenvironment.

Cancer arises in the context of an in vivo tumor microenvironment. This microenvironment is both a cause and consequence of tumorigenesis. Tumor and host cells co-evolve dynamically through indirect and direct cellular interactions, eliciting multiscale effects on many biological programs, including cellular proliferation, growth, and metabolism, as well as angiogenesis and hypoxia and innate and adaptive immunity. Here we highlight specific biological processes that could be exploited as targets for the prevention and therapy of cancer. Specifically, we describe how inhibition of targets such as cholesterol synthesis and metabolites, reactive oxygen species and hypoxia, macrophage activation and conversion, indoleamine 2,3-dioxygenase regulation of dendritic cells, vascular endothelial growth factor regulation of angiogenesis, fibrosis inhibition, endoglin, and Janus kinase signaling emerge as examples of important potential nexuses in the regulation of tumorigenesis and the tumor microenvironment that can be targeted. We have also identified therapeutic agents as approaches, in particular natural products such as berberine, resveratrol, onionin A, epigallocatechin gallate, genistein, curcumin, naringenin, desoxyrhapontigenin, piperine, and zerumbone, that may warrant further investigation to target the tumor microenvironment for the treatment and/or prevention of cancer.

Under a Creative Commons license.-- Review.-- et al., Targeted therapies and the consequent adoption of >personalized> oncology have achieved notablesuccesses in some cancers; however, significant problems remain with this approach. Many targetedtherapies are highly toxic, costs are extremely high, and most patients experience relapse after a fewdisease-free months. Relapses arise from genetic heterogeneity in tumors, which harbor therapy-resistantimmortalized cells that have adopted alternate and compensatory pathways (i.e., pathways that are notreliant upon the same mechanisms as those which have been targeted). To address these limitations, aninternational task force of 180 scientists was assembled to explore the concept of a low-toxicity >broad-spectrum> therapeutic approach that could simultaneously target many key pathways and mechanisms. Using cancer hallmark phenotypes and the tumor microenvironment to account for the various aspectsof relevant cancer biology, interdisciplinary teams reviewed each hallmark area and nominated a widerange of high-priority targets (74 in total) that could be modified to improve patient outcomes. For thesetargets, corresponding low-toxicity therapeutic approaches were then suggested, many of which werephytochemicals. Proposed actions on each target and all of the approaches were further reviewed forknown effects on other hallmark areas and the tumor microenvironment. Potential contrary or procar-cinogenic effects were found for 3.9% of the relationships between targets and hallmarks, and mixedevidence of complementary and contrary relationships was found for 7.1%. Approximately 67% of therelationships revealed potentially complementary effects, and the remainder had no known relationship. Among the approaches, 1.1% had contrary, 2.8% had mixed and 62.1% had complementary relationships. These results suggest that a broad-spectrum approach should be feasible from a safety standpoint. Thisnovel approach has potential to be relatively inexpensive, it should help us address stages and types ofcancer that lack conventional treatment, and it may reduce relapse risks. A proposed agenda for futureresearch is offered., Amr Amin was funded by Terry Fox Foundation Grant # TF-13-20 and UAEU Program for Advanced Research (UPAR) #31S118; Jack Arbiser was funded by NIHAR47901; Alexandra Arreola was funded by NIH NRSA Grant F31CA154080; Alla Arzumanyan was funded by NIH (NIAID) R01: Combination therapies for chronic HBV, liver disease, and cancer (AI076535); Work in the lab of Asfar S. Azmi is supported by NIH R21CA188818 as well as from Sky Foundation Inc. Michigan; Fabian Benencia was supported by NIH Grant R15 CA137499-01; Alan Bilsland was supported by the University of Glasgow, Beatson Oncology Centre Fund, CRUK (www.cancerresearchuk.org) Grant C301/A14762; Amancio Carnero was supported by grants from the Spanish Ministry of Economy and Competitivity, ISCIII (Fis: PI12/00137, RTICC: RD12/0036/0028) co-funded by FEDER from Regional Development European Funds (European Union), Consejeria de Ciencia e Innovacion (CTS-6844 and CTS-1848) and Consejeria de Salud of the Junta de Andalucia (PI-0135-2010 and PI-0306-2012). His work on this project has also been made possible thanks to the Grant PIE13/0004 co-funded by the ISCIII and FEDER funds; Stephanie C. Casey was supported by NIH Grant F32CA177139; Mrinmay Chakrabarti was supported by the United Soybean Board; Rupesh Chaturvedi was supported by an NIH NCCAM Grant (K01AT007324); Georgia Zhuo Chen was supported by an NIH NCI Grant (R33 CA161873-02); Helen Chen acknowledges financial support from the Michael Cuccione Childhood Cancer Foundation Graduate Studentship; Sophie Chen acknowledges financial support from the Ovarian and Prostate Cancer Research Trust, UK; Yi Charlie Chen acknowledges financial support from the West Virginia Higher Education Policy Commission/Division of Science Research, his research was also supported by NIH grants (P20RR016477 and P20GM103434) from the National Institutes of Health awarded to the West Virginia IDeA Network of Biomedical Research Excellence; Maria Rosa Ciriolo was partially supported by the Italian Association for Cancer Research (AIRC) Grants #IG10636 and #15403; Helen M. Coley acknowledges financial support from the GRACE Charity, UK and the Breast Cancer Campaign, UK; Marisa Connell was supported by a Michael Cuccione Childhood Cancer Foundation Postdoctoral Fellowship; Sarah Crawford was supported by a research grant from Connecticut State University; Charlotta Dabrosin acknowledges financial support from the Swedish Research Council and the Swedish Research Society; Giovanna Damia gratefully acknowledges the generous contributions of The Italian Association for Cancer Research (IG14536 to G.D.), Santanu Dasgupta gratefully acknowledges the support of the University of Texas Health Science Centre at Tyler, Elsa U. Pardee Foundation; William K. Decker was supported in part by CPRIT, the Cancer Prevention and Research Institute of Texas; Anna Mae E. Diehl was supported by NIH National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), the NIH National Institute on Alcohol Abuse and Alcoholism (NIAAA), Gilead and Shire Pharmaceuticals; Q. Ping Dou was partially supported by NIH/NCI (1R01CA20009, 5R01CA127258-05 and R21CA184788), and NIH P30 CA22453 (to Karmanos Cancer Institute); Janice E. Drew was supported by the Scottish Government's Rural and Environment Science and Analytical Services Division; Eyad Elkord thanks the National Research Foundation, United Arab Emirates University and the Terry Fox Foundation for supporting research projects in his lab; Bassel El-Rayes was supported by Novartis Pharmaceutical, Aveo Pharmaceutical, Roche, Bristol Myers Squibb, Bayer Pharmaceutical, Pfizer, and Kyowa Kirin; Mark A. Feitelson was supported by NIH/NIAID Grant AI076535, Dean W. Felsher was supported by NIH grants (R01CA170378, U54CA149145, and U54CA143907); Lynnette R Ferguson was financially supported by the Auckland Cancer Society and the Cancer Society of New Zealand; Gary L. Firestone was supported by NIH Public Service Grant CA164095 awarded from the National Cancer Institute; Christian Frezza “would like to acknowledge funding from a Medical Research Council CCU-Program Grant on cancer metabolism, and a unique applicant AICR project grant”; Mark M. Fuster was supported by NIH Grant R01-HL107652; Alexandros G. Georgakilas was supported by an EU Marie Curie Reintegration Grant MC-CIG-303514, Greek National funds through the Operational Program ‘Educational and Lifelong Learning of the National Strategic Reference Framework (NSRF)-Research Funding Program THALES (Grant number MIS 379346) and COST Action CM1201 ‘Biomimetic Radical Chemistry’; Michelle F. Green was supported by a Duke University Molecular Cancer Biology T32 Training Grant; Brendan Grue was supported by a National Sciences Engineering and Research Council Undergraduate Student Research Award in Canada; Dorota Halicka was supported by by NIH NCI grant NCI RO1 28704; Petr Heneberg was supported by the Charles University in Prague projects UNCE 204015 and PRVOUK P31/2012, by the Czech Science Foundation projects 15-03834Y and P301/12/1686, by the Czech Health Research Council AZV project 15-32432A, and by the Internal Grant Agency of the Ministry of Health of the Czech Republic project NT13663-3/2012; Matthew D. Hirschey wishes to acknowledge Duke University Institutional Support, the Duke Pepper Older Americans Independence Center (OAIC) Program in Aging Research supported by the National Institute of Aging (P30AG028716-01) and NIH/NCI training grants to Duke University (T32-CA059365-19 and 5T32-CA059365), Lorne J. Hofseth was supported by NIH grants (1R01CA151304, 1R03CA1711326, and 1P01AT003961); Kanya Honoki was supported in part by the grant from the Ministry of Education, Culture, Sports, Science and Technology, Japan (No. 24590493); Hsue-Yin Hsu was supported in part by grants from the Ministry of Health and Welfare (CCMP101-RD-031 and CCMP102-RD-112) and Tzu-Chi University (61040055-10) of Taiwan; Lasse D. Jensen was supported by Svenska Sallskapet for Medicinsk Forskning, Gosta Fraenkels Stiftelse, Ak.e Wibergs Stiftelse, Ollie och Elof Ericssons Stiftelse, Linkopings Universitet and the Karolinska Institute, Sweden; Wen G. Jiang wishes to acknowledge the support by Cancer Research Wales, the Albert Hung Foundation, the Fong Family Foundation, and Welsh Government A4B scheme; Lee W. Jones was supported in part by grants from the NIH NCI; W Nicol Keith was supported by the University of Glasgow, Beatson Oncology Centre Fund, CRUK (www.cancerresearchuk.org) Grant C301/A14762; Sid P. Kerkar was supported by the NIH Intramural Research Program; Rob J. Kulathinal was supported by the National Science Foundation, and the American Cancer Society; Byoung S. Kwon was supported in part by National Cancer Center (NCC-1310430-2) and National Research Foundation (NRF-2005-0093837); Anne Le was supported by Sol Goldman Pancreatic Cancer Research Fund Grant 80028595, a Lustgarten Fund Grant 90049125 and Grant NIHR21CA169757 (to Anne Le); Michael A. Lea was funded by the The Alma Toorock Memorial for Cancer Research; Ho-Young Lee., This work was supported by grants from the National Research Foundation of Korea (NRF), the Ministry of Science, ICT & Future Planning (MSIP), Republic of Korea (Nos. 2011-0017639 and 2011-0030001) and by a NIH Grant R01 CA100816; Liang-Tzung Lin was supported in part by a grant from the Ministry of Education of Taiwan (TMUTOP103005-4); Jason W. Locasale acknowledges support from NIH awards (CA168997 and AI110613) and the International Life Sciences Institute; Bal L. Lokeshwar was supported in part by United States’ Public Health Services Grants: NIH R01CA156776 and VA-BLR&D Merit Review Grant No. 5I01-BX001517-02; Valter D. Longo acknowledges support from NIH awards (P01AG034906 and R01AG020642) and from the V Foundation; Costas A. Lyssiotis was funded in part by the Pancreatic Cancer Action Network as a Pathway to Leadership Fellow and through a Dale F. Frey Breakthrough award from the Damon Runyon Cancer Research Foundation; Karen L. MacKenzie wishes to acknowledge the support from the Children's Cancer Institute Australia (affiliated with the University of New South Wales, Australia and the Sydney Children's Hospital Network); Maria Marino was supported by grant from University Roma Tre to M.M. (CLA 2013) and by the Italian Association for Cancer Research (AIRC-Grant #IG15221), Ander Matheu is funded by Carlos III Health Institute (AM: CP10/00539), Basque Foundation for Science (IKERBASQUE) and Marie Curie CIG Grant (AM: 2012/712404); Christopher Maxwell was supported by funding from the Canadian Institutes of Health Research, in partnership with the Avon Foundation for Women (OBC-134038) and the Canadian Institutes of Health Research New Investigator Salary Award (MSH-136647); Eoin McDonnell received Duke University Institutional Support; Kapil Mehta was supported by Bayer Healthcare System G4T (Grants4Targets); Gregory A. Michelotti received support from NIH NIDDK, NIH NIAAA, and Shire Pharmaceuticals; Vinayak Muralidhar was supported by the Harvard-MIT Health Sciences and Technology Research Assistantship Award; Elena Niccolai was supported by the Italian Ministry of University and the University of Italy; Virginia R. Parslow gratefully acknowledges the financial support of the Auckland Cancer Society Research Centre (ACSRC); Graham Pawelec was supported by the German Federal Ministry of Education and Research (Bundesministerium für Bildung und Forschung, BMBF) Grant number 16SV5536K, and by the European Commission (FP7 259679 “IDEAL”); Peter L. Pedersen was supported by NIH Grant CA-10951; Brad Poore was supported by Sol Goldman Pancreatic Cancer Research Fund Grant 80028595, the Lustgarten Fund Grant 90049125, and Grant NIHR21CA169757 (to Anne Le); Satya Prakash was supported by a Canadian Institutes of Health Research Grant (MOP 64308); Lizzia Raffaghello was supported by an NIH Grant (P01AG034906-01A1) and Cinque per Mille dell’IRPEF–Finanziamento della Ricerca Sanitaria; Jeffrey C. Rathmell was supported by an NIH Grant (R01HL108006); Swapan K. Ray was supported by the United Soybean Board; Domenico Ribatti received funding from the European Union Seventh Framework Programme (FP7/2007–2013) under Grant agreement n°278570; Luigi Ricciardiello was supported by the AIRC Investigator Grants 10216 and 13837, and the European Community's Seventh Framework Program FP7/2007–2013 under Grant agreement 311876; Francis Rodier acknowledges the support of the Canadian Institute for Health Research (FR: MOP114962, MOP125857), Fonds de Recherche Québec Santé (FR: 22624), and the Terry Fox Research Institute (FR: 1030), Gian Luigi Russo contributed to this effort while participating in the Fulbright Research Scholar Program 2013–14; Isidro Sanchez-Garcia is partially supported by FEDER and by MICINN (SAF2012-32810), by NIH Grant (R01 CA109335-04A1), by Junta de Castilla y León (BIO/SA06/13) and by the ARIMMORA project (FP7-ENV-2011, European Union Seventh Framework Program). Isidro Sanchez-Garcia's lab is also a member of the EuroSyStem and the DECIDE Network funded by the European Union under the FP7 program; Andrew J. Sanders wishes to acknowledge the support by Cancer Research Wales, the Albert Hung Foundation, the Fong Family Foundation, and Welsh Government A4B scheme; Neeraj K. Saxena was supported by grant funding from NIH NIDDK (K01DK077137, R03DK089130); Dipali Sharma was partially funded by NIH NCI grants (R01CA131294, R21 CA155686), the Avon Foundation and a Breast Cancer Research Foundation Grant (90047965); Markus David Siegelin received funding from National Institute of Health, NINDS Grant K08NS083732, and the 2013 AACR-National Brain Tumor Society Career Development Award for Translational Brain Tumor Research, Grant Number 13-20-23-SIEG; Neetu Singh was supported by funds from the Department of Science and Technology (SR/FT/LS-063/2008), New Delhi, India; Carl Smythe was supported by Yorkshire Cancer Research and The Wellcome Trust, UK; Carmela Spagnuolo was supported by funding from Project C.I.S.I.A., act n. 191/2009 from the Italian Ministry of Economy and Finance Project CAMPUS-QUARC, within program FESR Campania Region 2007/2013, objectives 2.1, 2.2; Diana M. Stafforini was supported by grants from the National Cancer Institute (5P01CA073992), IDEA Award W81XWH-12-1-0515 from the Department of Defense, and by the Huntsman Cancer Foundation; John Stagg was supported by the Canadian Institutes of Health Research; Pochi R. Subbarayan was supported by the University of Miami Clinical and Translational Science Institute (CTSI) Pilot Research Grant (CTSI-2013-P03) and SEEDS You Choose Awards; Phuoc T. Tran was funded by the DoD (W81XWH-11-1-0272 and W81XWH-13-1-0182), a Kimmel Translational Science Award (SKF-13-021), an ACS Scholar award (122688-RSG-12-196-01-TBG) and the NIH (R01CA166348); Kathryn E. Wellen receives funding from the National Cancer Institute, Pancreatic Cancer Action Network, Pew Charitable Trusts, American Diabetes Association, and Elsa U. Pardee Foundation; Huanjie Yang was partially supported by the Scientific Research Foundation for the Returned Oversea Scholars, State Education Ministry and Scientific and Technological Innovation Project, Harbin (2012RFLXS011), Paul Yaswen was supported by funding from the United States National Institutes of Health (ES019458) and the California Breast Cancer Research Program (17UB-8708); Clement Yedjou was supported by a grant from the National Institutes of Health (Grant # G1200MD007581), through the RCMI-Center for Environmental Health; Xin Yin was supported by NIH/National Heart, Lung, and Blood Institute Training Grant T32HL098062.; Jiyue Zhu was supported by NIH Grant R01GM071725; Massimo Zollo was supported by the European FP7-TuMIC HEALTH-F2-2008-201662, the Italian Association for Cancer research (AIRC) Grant IG # 11963 and the Regione Campania L.R:N.5, the European National Funds PON01-02388/1 2007-2013.

Oncogene control of antitumor immunity Recent clinical success of cancer immunotherapy has intensified interest in how tumors normally evade the immune response. Whether and how oncogenes contribute to this process are not well understood. In a study of mice, Casey et al. found that the MYC oncogene, which is aberrantly activated in many human cancers, up-regulates the expression of genes encoding proteins that dampen the antitumor response. These include two proteins that are often overexpressed on tumor cells and that serve as immune checkpoints. One of them (PDL1) sends to the immune system a “don't find me” signal, and the other (CD47) sends a “don't eat me” signal. Thus, therapies aimed at suppressing MYC may help promote an immune response against tumors. Science , this issue p. 227

Potentially carcinogenic compounds may cause cancer through direct DNA damage or through indirect cellular or physiological effects. To study possible carcinogens, the fields of endocrinology, genetics, epigenetics, medicine, environmental health, toxicology, pharmacology and oncology must be considered. Disruptive chemicals may also contribute to multiple stages of tumor development through effects on the tumor microenvironment. In turn, the tumor microenvironment consists of a complex interaction among blood vessels that feed the tumor, the extracellular matrix that provides structural and biochemical support, signaling molecules that send messages and soluble factors such as cytokines. The tumor microenvironment also consists of many host cellular effectors including multipotent stromal cells/mesenchymal stem cells, fibroblasts, endothelial cell precursors, antigen-presenting cells, lymphocytes and innate immune cells. Carcinogens can influence the tumor microenvironment through effects on epithelial cells, the most common origin of cancer, as well as on stromal cells, extracellular matrix components and immune cells. Here, we review how environmental exposures can perturb the tumor microenvironment. We suggest a role for disrupting chemicals such as nickel chloride, Bisphenol A, butyltins, methylmercury and paraquat as well as more traditional carcinogens, such as radiation, and pharmaceuticals, such as diabetes medications, in the disruption of the tumor microenvironment. Further studies interrogating the role of chemicals and their mixtures in dose-dependent effects on the tumor microenvironment could have important general mechanistic implications for the etiology and prevention of tumorigenesis.

Cancers due to germline mutations in the BRCA1 gene tend to lack targets for approved chemoprevention agents. This study aimed at a targeted chemoprevention strategy for BRCA1-associated malignancies. Mutant BRCA1 limits the base-excision DNA repair activity that addresses oxidative DNA damage, the accumulation of which heightens one's risk for cancer. Therefore, we conducted a high-throughput chemical screen to identify drug candidates that could attenuate the inhibitory effects of mutant BRCA1 on this repair activity, thereby describing a new class of DNA repair-activating chemopreventive agents. In the screen design, such drugs functioned by enhancing base-excision DNA repair of oxidative DNA damage in the presence of mutant BRCA1, with minimal cytotoxicity. We identified at least one new agent that decreased malignant properties associated with tumorigenesis, including anchorage-independent growth and tumor progression. This work offers a preclinical proof-of-concept for a wholly new approach to chemoprevention in carriers of BRCA1 mutations as a strategy to reduce the prevalence of BRCA1-associated malignancy. Cancer Res; 74(21); 6205–15. ©2014 AACR.

The MYC proto-oncogene is an essential regulator of many normal biological programmes. MYC, when activated as an oncogene, has been implicated in the pathogenesis of most types of human cancers. MYC overexpression in normal cells is restrained from causing cancer through multiple genetically and epigenetically controlled checkpoint mechanisms, including proliferative arrest, apoptosis and cellular senescence. When pathologically activated in the correct epigenetic and genetic contexts, MYC bypasses these mechanisms and drives many of the ‘hallmark’ features of cancer, including uncontrolled tumour growth associated with DNA replication and transcription, cellular proliferation and growth, protein synthesis and altered cellular metabolism. MYC also dictates tumour cell fate by enforcing self-renewal and by abrogating cellular senescence and differentiation programmes. Moreover, MYC influences the tumour microenvironment, including activating angiogenesis and suppressing the host immune response. Provocatively, brief or even partial suppression of MYC back to its physiological levels of activation can lead to the restoration of intrinsic checkpoint mechanisms, resulting in acute and sustained tumour regression associated with tumour cells undergoing proliferative arrest, differentiation, senescence and apoptosis, as well as remodelling of the tumour microenvironment, recruitment of an immune response and shutdown of angiogenesis. Hence, tumours appear to be addicted to the MYC oncogene because of both tumour cell intrinsic and host-dependent mechanisms. MYC is important for the regulation of both the initiation and maintenance of tumorigenesis.

Summary Tumor endothelial cells (ECs) promote cancer progression in ways beyond their role as conduits supporting metabolism. However, it is unknown how vascular niche-derived paracrine factors, defined as angiocrine factors, provoke tumor aggressiveness. Here, we show that FGF4 produced by B cell lymphoma cells (LCs) through activating FGFR1 upregulates the Notch ligand Jagged1 (Jag1) on neighboring ECs. In turn, upregulation of Jag1 on ECs reciprocally induces Notch2-Hey1 in LCs. This crosstalk enforces aggressive CD44 + IGF1R + CSF1R + LC phenotypes, including extranodal invasion and chemoresistance. Inducible EC-selective deletion of Fgfr1 or Jag1 in the Eμ-Myc lymphoma model or impairing Notch2 signaling in mouse and human LCs diminished lymphoma aggressiveness and prolonged mouse survival. Thus, targeting the angiocrine FGF4-FGFR1/Jag1-Notch2 loop inhibits LC aggressiveness and enhances chemosensitivity.

Cancer is highly complex. The magnitude of this complexity makes it highly surprising that even the brief suppression of an oncogene can sometimes result in rapid and sustained tumor regression, illustrating that cancers can be ‘oncogene addicted’ [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ]. The essential implication is that oncogenes may not only fuel the initiation of tumorigenesis, but in some cases must be excessively activated to maintain a neoplastic state [ 11 ]. Oncogene suppression acutely restores normal physiological programs that effectively overrides secondary genetic events and a cancer collapses [ 12 , 13 ]. Oncogene addiction is the description of the dramatic and sustained regression of some cancers upon the specific inactivation of a single oncogene [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14•• , 15 , 16•• ], that can occur through tumor intrinsic [ 1 , 2 , 4 , 12 ], but also host immune mechanisms [ 17 , 18 , 19 , 20 , 21 , 22•• , 23•• ]. Notably, oncogene inactivation elicits a host immune response that involves specific immune effectors and cytokines that facilitate a remodeling of the tumor microenvironment including the shut down of angiogenesis and the induction of cellular senescence of tumor cells [ 16•• ]. Hence, immune effectors are not only critically involved in tumor prevention, initiation [ 17 , 18 , 19 ], and progression [ 20 ], but also appear to be essential to tumor regression upon oncogene inactivation [ 21 , 22•• , 23•• ]. Understanding how the inactivation of an oncogene elicits a systemic signal in the host that prompts a deconstruction of a tumor could have important implications. The combination of oncogene-targeted therapy together with immunomodulatory therapy may be ideal for the development of both robust tumor intrinsic and immunological responses, effectively leading to sustained tumor regression.

The “common sense” intervention by toxicology journal editors regarding proposed European Union endocrine disrupter regulations ignores scientific evidence and well-established principles of chemical risk assessment. In this commentary, endocrine disrupter experts express their concerns about a recently published, and is in our considered opinion inaccurate and factually incorrect, editorial that has appeared in several journals in toxicology. Some of the shortcomings of the editorial are discussed in detail. We call for a better founded scientific debate which may help to overcome a polarisation of views detrimental to reaching a consensus about scientific foundations for endocrine disrupter regulation in the EU., Environmental Health, 12 (1), ISSN:1476-069X

Research Bisphenol A Diglycidyl Ether Induces Adipogenic Differentiation of Multipotent Stromal Stem Cells through a Peroxisome Proliferator–Activated Receptor Gamma-Independent Mechanism Raquel Chamorro-Garcia, 1, * Severine Kirchner, 1, * Xia Li, 1 Amanda Janesick, 1 Stephanie C. Casey, 1 Connie Chow, 1 and Bruce Blumberg 1,2 1 Department of Developmental and Cell Biology, and 2 Department of Pharmaceutical Sciences, University of California, Irvine, Irvine, California, USA B ackground : Bisphenol A (BPA) and bisphenol A diglycidyl ether (BADGE), used in ­manufacturing coatings and resins, leach from packaging materials into food. Numerous studies suggested that BPA and BADGE may have adverse effects on human health, including the possibil- ity that exposure to such chemicals can be superimposed on traditional risk factors to initiate or exacerbate the development of obesity. BPA is a suspected obesogen, whereas BADGE, described as a peroxisome proliferator–activated receptor gamma (PPARγ) antagonist, could reduce weight gain. O bjectives : We sought to test the adipogenic effects of BADGE in a biologically relevant cell ­culture model. M ethods : We used multipotent mesenchymal stromal stem cells (MSCs) to study the adipogenic capacity of BADGE and BPA and evaluated their effects on adipogenesis, osteogenesis, gene expres- sion, and nuclear receptor activation. D iscussion : BADGE induced adipogenesis in human and mouse MSCs, as well as in mouse 3T3-L1 pre­adipocytes. In contrast, BPA failed to promote adipogenesis in MSCs, but induced adipogenesis in 3T3-L1 cells. BADGE exposure elicited an adipogenic gene expression profile, and its ability to induce adipogenesis and the expression of adipogenic genes was not blocked by known PPARγ antagonists. Neither BADGE nor BPA activated or antagonized retinoid “X” receptor (RXR) or PPARγ in transient transfection assays. C onclusions : BADGE can induce adipogenic differentiation in both MSCs and in pre­adipocytes at low nanomolar concentrations comparable to those that have been observed in limited human bio­ monitoring. BADGE probably acts through a mechanism that is downstream of, or parallel to, PPARγ. K ey words : adipogenesis, BADGE, BPA, endocrine disruption, MSCs, obesogen, PPARγ. Environ Health Perspect 120:984–989 (2012). http://dx.doi.org/10.1289/ehp.1205063 [Online 25 May Bisphenol A (BPA) is used in the synthesis of polycarbonate plastics, epoxy adhesives, and the lining of food containers. Bisphenol A diglycidyl ether (BADGE) is a synthesis prod- uct of BPA and epichlorhydrin used in the manufacture of epoxy resins, paints, and as a coating on food containers. BPA and BADGE are present in many commonly used prod- ucts including beverage containers, baby bottles, and dental composites. Both migrate from containers into foods, and are routinely ingested (Cabado et al. 2008; Cao et al. 2009). Studies of BADGE metabolism suggest that it is not a significant source of BPA (Climie et al. 1981) although BPA leaches from some BADGE-containing dental sealants (Joskow et al. 2006; Olea et al. 1996). BPA is an environmental endocrine- ­disrupting chemical (EDC) found in 95% of human urine samples (Calafat et al. 2008) as well as in serum, breast milk, and fat (reviewed by Rubin 2011; Taylor et al. 2011). Despite some controversy, the prevailing view in the scientific community is that BPA has impor- tant, deleterious effects in animals by acting on multiple target tissues (reviewed by Rubin 2011; Taylor et al. 2011), and BPA levels have been associated with adverse health outcomes in humans (Lang et al. 2008). Estrogenic and anti­androgenic effects of BADGE have been reported (Olea et al. 1996; Satoh et al. 2004); however, the manu­facturers of BADGE have disputed any endocrine- ­disrupting, oncogenic, or mutagenic effects (Poole et al. 2004). BADGE and its chloro­ hydroxy derivatives induced proliferation of human breast cancer cells but did not bind to the estrogen receptor (Nakazawa et al. 2002). BADGE exposure caused developmental tox- icity during gestation and lactation in rats (Hyoung et al. 2007) and toxicity in cell cul- ture (Ramilo et al. 2006). Overall, the pres- ence of BADGE in food cannot be considered a health benefit and may be a health risk. Obesity is caused by complex interactions among genetic, behavioral, and environmental factors, and EDC exposure is now thought to be a risk factor for obesity (reviewed by Janesick and Blumberg 2011; La Merrill and Birnbaum 2011; Tang-Peronard et al. 2011). Our “obesogen hypothesis” proposes a link between developmental EDC exposure and obesity. Obesogens are functionally defined as chemicals that promote obesity by increas- ing the number of fat cells (and fat storage into existing fat cells) by changing the amount of calories burned at rest, by altering energy balance to favor storage of calories, and by volume altering the mechanisms through which the body regulates appetite and satiety (reviewed by Janesick and Blumberg 2011). Most evidence suggests that BPA acts as an obesogen, in vitro and in vivo. BPA induced adipocyte differentiation and adipo- genic marker genes in 3T3-L1 pre­adipocytes (Masuno et al. 2005). Perinatal treatment of rats (Rubin et al. 2001; Somm et al. 2009) and mice (Miyawaki et al. 2007) with low doses of BPA led to increased fat mass (reviewed by Rubin 2011). Some studies suggested that different BPA dosing regimens might not increase body weight in rats (Nunez et al. 2001; Seidlova-Wuttke et al. 2005) or mice (Ryan et al. 2010), and thus further studies are needed to clarify exactly how BPA pro- motes adipogenesis and obesity. The obesogenic properties of BADGE are yet to be thoroughly investigated. BADGE was identified as an antagonist of peroxi- some proliferator–­activated receptor gamma (PPARγ) [its IC 50 (the concentration of BADGE at which 50% inhibition of the response is observed) is approximately 100 µM] that also inhibits differentiation of 3T3-L1 and 3T3‑F442A pre­adipocytes (Wright et al. 2000). BADGE administered orally at high doses to mice on a high-fat diet decreased tri­ glyceride content in white adipose tissue, skele- tal muscle, and the liver due to increased leptin (LEP) effects and increased fatty acid combus- tion and energy dissipation, thereby ameliorat- ing high-fat diet–induced obesity and insulin resistance (Yamauchi et al. 2001; Yun et al. Address correspondence to B. Blumberg, U.C. Irvine, 2011 BioSci 3, Irvine, CA 92697-2300, USA. Telephone: (949) 824-8573. Fax: (949) 824-4709. E-mail: blumberg@uci.edu *These authors contributed equally to this work. Supplemental Material is available online (http:// dx.doi.org/10.1289/ehp.1205063). This work was supported by a grant from the National Institutes of Health (ES-015849) to B.B. S.C.C. was supported by grant T32CA009054 from the National Cancer Institute. A.J. is a pre- doctoral trainee sponsored by the National Science Foundation’s Integrative Graduate Education and Research Traineeship program (NSF-IGERT) Life Chips Award, Division of Graduate Education (DGE) grant 0549479. B.B. is a named inventor on U.S. patents 5,861,274, 6,200,802, 6,815,168, and 7,250,273 related to PPARγ. The other authors declare they have no actual or potential competing financial interests. Received 5 February 2012; accepted 27 April 2012. 120 | number 7 | July 2012 • Environmental Health Perspectives

The environmental obesogen hypothesis proposes that pre- and postnatal exposure to environmental chemicals contributes to adipogenesis and the development of obesity. Tributyltin (TBT) is an agonist of both retinoid X receptor (RXR) and peroxisome proliferator-activated receptor γ (PPARγ). Activation of these receptors can elevate adipose mass in adult mice exposed to the chemical in utero. Here we show that TBT sensitizes human and mouse multipotent stromal stem cells derived from white adipose tissue [adipose-derived stromal stem cells (ADSCs)] to undergo adipogenesis. In vitro exposure to TBT, or the PPARγ activator rosiglitazone increases adipogenesis, cellular lipid content, and expression of adipogenic genes. The adipogenic effects of TBT and rosiglitazone were blocked by the addition of PPARγ antagonists, suggesting that activation of PPARγ mediates the effect of both compounds on adipogenesis. ADSCs from mice exposed to TBT in utero showed increased adipogenic capacity and reduced osteogenic capacity with enhanced lipid accumulation in response to adipogenic induction. ADSCs retrieved from animals exposed to TBT in utero showed increased expression of PPARγ target genes such as the early adipogenic differentiation gene marker fatty acid-binding protein 4 and hypomethylation of the promoter/enhancer region of the fatty acid-binding protein 4 locus. Hence, TBT alters the stem cell compartment by sensitizing multipotent stromal stem cells to differentiate into adipocytes, an effect that could likely increase adipose mass over time.