Nianjun Tao

Compensatory insulin receptor (IR) activation on inhibition of insulin-like growth factor-1 receptor (IGF-1R): rationale for cotargeting IGF-1R and IR in cancer.

Insulin-like growth factor-1 receptor (IGF-1R) is a receptor tyrosine kinase (RTK) and critical activator of the phosphatidylinositol 3-kinase–AKT pathway. IGF-1R is required for oncogenic transformation and tumorigenesis. These observations have spurred anticancer drug discovery and development efforts for both biological and small-molecule IGF-1R inhibitors. The ability for one RTK to compensate for another to maintain tumor cell viability is emerging as a common resistance mechanism to antitumor agents targeting individual RTKs. As IGF-1R is structurally and functionally related to the insulin receptor (IR), we asked whether IR is tumorigenic and whether IR-AKT signaling contributes to resistance to IGF-1R inhibition. Both IGF-1R and IR(A) are tumorigenic in a mouse mammary tumor model. In human tumor cells coexpressing IGF-1R and IR, bidirectional cross talk was observed following either knockdown of IR expression or treatment with a selective anti–IGF-1R antibody, MAB391. MAB391 treatment resulted in a compensatory increase in phospho-IR, which was associated with resistance to inhibition of IRS1 and AKT. In contrast, treatment with OSI-906, a small-molecule dual inhibitor of IGF-1R/IR, resulted in enhanced reduction in phospho-IRS1/phospho-AKT relative to MAB391. Insulin or IGF-2 activated the IR-AKT pathway and decreased sensitivity to MAB391 but not to OSI-906. In tumor cells with an autocrine IGF-2 loop, both OSI-906 and an anti–IGF-2 antibody reduced phospho-IR/phospho-AKT, whereas MAB391 was ineffective. Finally, OSI-906 showed superior efficacy compared with MAB391 in human tumor xenograft models in which both IGF-1R and IR were phosphorylated. Collectively, these data indicate that cotargeting IGF-1R and IR may provide superior antitumor efficacy compared with targeting IGF-1R alone. Mol Cancer Ther; 9(10); 2652–64. ©2010 AACR.

Plasma growth differentiation factor 15 is associated with weight loss and mortality in cancer patients.

Cancer‐related weight loss is associated with increased inflammation and decreased survival. The novel inflammatory mediator growth differentiation factor (GDF)15 is associated with poor prognosis in cancer but its role in cancer‐related weight loss (C‐WL) remains unclear. Our objective was to measure GDF15 in plasma samples of cancer subjects and controls and establish its association with other inflammatory markers and clinical outcomes.

Abstract 4650: From bench to bedside: are cytokines still relevant biomarkers for staging cancer cachexia.

Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC Background: We have provided initial evidence1 on the clinical usefulness of the cancer cachexia stages (CCS) proposed by Fearon et al2. However it is still unclear3 if particular molecular phenotypes are also associated with these stages, as well with relevant clinical outcomes. Methods: A candidate list of cytokines (Activin A, Eotaxin, FGF, G-CSF, GDF15, GM-CSF, IFN-g, IL-10, IL-12\_p70, IL-13, IL-15, IL-17, IL-1b, IL-1ra, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-9, IP-10, MCP-1\_MCAF, MIP-1a, MIP-1b, PDGF-bb, RANTES, TNF-a, VEGF) was measured in 210 blood samples from patients with advanced lung and gastrointestinal cancers, via Luminex and ELISA methods. Non-parametric t-test, Kaplan-Meier and Kruskal-Wallis analyses were used to test the association between cytokines levels with CCS, Patient-Generated Subjective Global Assessment scores (PG-SGA) and survival. Results: Using non-cachectic patients as controls, Activin A and GDF15 were significantly up-regulated in pre-cachectic (p<0.01), cachectic (p<0.05) and refractory cachectic (p<0.001) patients. IL-6, IL-8 and VEGFa were significantly up-regulated only in refractory cachectic (p<0.001) patients. Activin A (p<0.001), GDF15 (p<0.001) and IL-8 (P<0.001) plasma levels correlated with PG-SGA. Quartiles of GDF15 plasma levels identified better survival curves as compared to Activin A, IL-6 and IL-8 quartiles. Conclusions: Activin A and GDF15 appear to be useful aids for the diagnosis of all cachexia stages in advanced cancer. Because of their correlation with nutritional and survival outcomes, these cytokines may also represent useful targets in the development of new compounds for the treatment of cancer cachexia. 1. Vigano A, Del Fabbro E, Bruera E, Borod M. The cachexia clinic: from staging to managing nutritional and functional problems in advancer cancer patients. Critical Reviews in Oncogenesis, 2012 17(3), 293-304 2. Fearon K,Strasser F,Anker SD,Bosaeus I,Bruera E,Fainsinger RL,Jatoi A, Loprinzi C, MacDonald N, Mantovani G, Davis M, Muscaritoli M, Ottery F, Radbruch L, Ravasco P, Walsh D, Wilcock A, Kaasa S, Baracos VE. Definition and classification of cancer cachexia: an international consensus. Lancet Oncol. 2011; 12:489-495. 3. Scheede-Bergdahl, C., Watt, H.L., Trutschnigg, B., Kilgour, R.D., Haggarty, A., Lucar, E., Vigano, A. 2011. Is IL-6 the best pro-inflammatory biomarker of clinical outcomes of cancer cachexia? Clinical Nutrition 31: 85-8. Citation Format: Antonio Vigano, Lorena Lerner, Nianjun Tao, Brian Krieger, Bin Feng, Richard Nicoletti, Qing Liu, Ailin Bai, Zhigang Weng, Thierry Alcindor, Domenico Fuoco, Jeno Gyuris, Maria Isabel Chiu. From bench to bedside: are cytokines still relevant biomarkers for staging cancer cachexia. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4650. doi:10.1158/1538-7445.AM2013-4650

Abstract 1153: Effective treatment of cancer associated cachexia by AV-380, a GDF15 inhibitory antibody

Background: One of the most lethal and debilitating effects of cancer is the development of cancer-related anorexia-cachexia syndrome (CACS). It affects the majority of advanced cancer patients and is thought to be responsible for up to ∼30% of all cancer deaths. CACS is a complex metabolic syndrome associated with malnutrition and severe involuntary weight loss due to the loss of muscle and fat tissue, as well as the clinical manifestation of anemia, inflammation and suppression of immune functions. The precise molecular mechanisms responsible for cancer cachexia are poorly understood, thus limiting the development of effective therapeutics. Current evidence suggests that a pro-inflammatory state may be responsible for many of the symptoms associated with CACS. Growth Differentiation Factor 15 (GDF15) is a pro-inflammatory cytokine whose circulating levels are significantly increased in cachectic cancer patients and several animal models of cancer cachexia. Here we demonstrate that the inhibition of GDF15 function results in the compete reversion of the phenotypic and metabolic changes associated with CASC. Methods: Mice bearing HT-1080 human fibrosarcoma xenografts have increased plasma GDF15 levels and develop cachexia were used in this study. Tumor bearing animals were treated either with AV-380, a GDF15 neutralizing antibody or IgG1 control. The effect on body weight, muscle/fat mass and organ sizes were assessed. Metabolic changes induced by the treatment were measured by a comprehensive laboratory animal monitoring system (CLAMS). Results: Treatment with AV-380 restored body weight, muscle and fat mass as well as normal organ sizes. Analyses of the CLAMS data demonstrated that mice receiving AV-380 reversed the phenotypic and metabolic changes associated with the cachexia induced by this tumor model. Moreover, AV-380 treated mice showed an increase in locomotor activity and energy expenditure, achieving levels similar to non tumor bearing control animals. Conclusions: Inhibition of GDF15 function completely reverted body weight loss, restored normal body composition and triggered a catabolic to anabolic metabolic switch in this cancer cachexia model. The data highlights the therapeutic potential of the GDF15 inhibitory antibody AV-380 for the treatment for CACS. Citation Format: Lorena Lerner, Nianjun Tao, Brian Krieger, Richard Nicoletti, Bin Feng, Nesreen Ismail, William Winston, Yanyu Zhang, Jinwei Jiang, Solly Weiler, Jeno Gyuris. Effective treatment of cancer associated cachexia by AV-380, a GDF15 inhibitory antibody. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1153. doi:10.1158/1538-7445.AM2015-1153

Abstract 3504: Plasma growth differentiating factor-15 (GDF-15) and other inflammatory markers are associated with weight loss and poor prognosis in cancer patients.

Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC Background: Cachexia is associated with increased inflammatory markers and decreased survival in cancer. Also, elevated GDF-15 has been associated with poor prognosis in several cancer types but its role in cachexia is not well-understood. Methods: We measured body weight change, appetite, plasma GDF-15, and other inflammatory markers in 62 males with cancer-cachexia (CC), 72 non-cachectic cancer subjects (CNC) and 64 non-cancer controls (Co) matched by age, gender and pre-illness body weight. In a subset of patients we also measured grip strength (HGS), appendicular lean body mass (aLBM), ECOG and KPS. Results: GDF-15, IL-6 and IL-8 were increased in CC vs. other groups. Activin and G-CSF were significantly upregulated in CC vs. Co. A subset analyses showed that GDF-15, Activin A and IL-8 were increased in CC vs. CNC in lung cancer patients and that GDF-15, IL-6 and IL-8 were increased in CC patients treated with platinum-based chemotherapy. GDF15, IL-6 and IL-8 levels significantly correlated with 6-month weight loss and with IL-6, IL-1ra, IL-2, IL-4, IL-9, IL-10, IFN, MCP-10, MIP-1a, MIP-1b, TNF-a, VGEF and activin in cancer patients. Analysis in a subset of patients showed that CC had lower grip strength, aLBM, and fat mass; and that ECOG and KPS were lower in CC and CNC compared to controls. GDF-15 and IL-8 correlated negatively with aLBM, HGS and fat mass. Activin correlated negatively with aLBM. Survival analysis showed that GDF-15 and IL-8 predicted survival adjusting for stage and weight change (Cox regression p<0.01, HR 3). Conclusion: GDF-15 and other inflammatory markers are associated with weight loss, decreased muscle mass and strength and poor survival in cancer patients. GDF-15 may serve as a prognostic indicator in cancer patients and be a novel therapeutic target for cancer cachexia. Citation Format: Lerner Lorena, Teresa Hayes, Nianjun Tao, Brian Krieger, Bin Feng, Richard Nicoletti, Ailin Bai, Zhigang Weng, Qing Liu, Maria Isabel Chiu, Jeno Gyuris, Jose M. Garcia. Plasma growth differentiating factor-15 (GDF-15) and other inflammatory markers are associated with weight loss and poor prognosis in cancer patients. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3504. doi:10.1158/1538-7445.AM2013-3504

Abstract 1441: Induction of cancer cachexia by inflammatory molecules in directed complementation tumor models

Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Cancer cachexia is a complex multi-factorial syndrome characterized by anorexia, body weight loss that is primarily due to the loss of skeletal muscle and adipose tissue, as well as systemic inflammation. It affects the majority of advanced cancer patients, being the cause of death in 20% to 40% of the cases. Although inflammation is recognized as an important component of cancer cachexia, the role of individual cytokines is poorly understood. Our analyses of inflammatory markers in two independent human cancer cachexia plasma collections identified several cytokines (GDF-15, Activin-A, IL-6 and IL-8) that are consistently upregulated in cancer cachexia patients. To examine the ability of these cytokines to induce cancer cachexia, we utilized an inducible breast cancer model as the background in which to create a panel of genetically-engineered mouse tumor models that overexpress targets of interests, namely GDF15, Activin A and IL-6. Such complemented tumor models present a unique preclinical opportunity for dissecting the role of candidate markers in vivo, in part because they were generated on a genetically homogeneous background, allowing the role of each individual target to be identified and differentiated. Mice bearing tumors that overexpress each inflammatory marker were characterized for phenotypic manifestation of cachexia. Mice bearing tumors that overexpress GDF15 (or MIC-1, macrophage inhibitory cytokine-1) developed severe cachexia with a rapid onset of body weight loss as well as changes in body composition. Overexpression of Activin A or IL-6 induced partial body weight loss with a milder cachexia phenotype at concentrations significantly higher that seen in cachexic human patients, while mice bearing control tumors without the engineered expression of an inflammatory cytokine showed no detectable changes in either body weight or body composition. These results indicate that the elevated expression of GDF-15 and to a lesser extent Activin A, and IL-6 can result in the development of cancer cachexia and may represent attractive therapeutic targets. Citation Format: Qing Liu, Lorena Lerner, Zakir Siddiquee, Lucia Huang, Ruojie Wang, Nianjun Tao, Brian Krieger, Isabel Chiu, Jeno Gyuris. Induction of cancer cachexia by inflammatory molecules in directed complementation tumor models. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1441. doi:10.1158/1538-7445.AM2014-1441

Abstract 1631: Tumorigenicity of IGF-1R and IR: Rationale for co-targeting IGF-1R and IR in cancer

Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL The Type 1 insulin-like growth factor receptor (IGF-1R) is a well established mediator of tumor cell proliferation and survival. IGF-1R is required for cellular transformation by a number of oncogenes including Ras, and expression of IGF-1R can promote tumor formation in vivo. Blockade of IGF-1R signaling by either genetic or pharmacological methods results in inhibition of tumor cell proliferation. This understanding has spurred the evaluation of a number of IGF-1R inhibitors in the clinic, including both neutralizing antibodies and small molecule kinase inhibitors. IGF-1R is structurally and functionally related to the insulin receptor (IR). Although IR is appreciated for its classical role in glucose metabolism, IR can also regulate cellular proliferation. Furthermore, there is evidence for compensatory crosstalk between IGF-1R and IR. In embryonic development IR signaling can compensate for loss of IGF-1R to maintain normal embryonic weight. A growing body of data indicates that tumor cells may also exploit IR signaling for proliferation and survival. Tumor cells frequently co-express both IGF-1R and IR, and increased expression of both IGF ligands and insulin are associated with increased risk of cancer. Elevated expression of the IR(A) fetal variant, which is potently activated by both insulin and IGF-2, is observed in select human tumors. Although the tumorigenicity for IGF-1R is well described, the potential for IR as a tumor maintenance gene in vivo has thus far not been established. Herein, we sought to address the tumorigenic potential for IGF-1R compared with IR(A). We used a mouse mammary tumor model driven by an inducible human HER2 oncogene under doxycyclin-directed expression, where repression of HER2 expression upon doxycyclin withdrawal was followed by introduction of genes encoding either IGF-1R or IR(A) in combination with IGF2. We find that either IGF-1R or IR(A), in combination with the ligand IGF2, can complement tumor growth. The growth of both IGF-1R and IR(A) direct complementation (DC) tumor models could be inhibited by the dual IGF-1R/IR small molecule inhibitor OSI-906. Cell lines derived from the IGF-1R and IR(A) DC tumors show that expression of either receptor individually can maintain signaling through the IRS-AKT signaling pathway. Collectively, these observations show that either IGF-1R or IR(A) have tumorigenic potential, and indicate that dual targeting of IGF-1R and IR may be required for optimal activity in tumors where both receptors are present and activated. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1631. doi:10.1158/1538-7445.AM2011-1631

Abstract 646: Identification of FURIN as a tumor maintenance gene in solid tumors by in vivo Retroviral Mutagenesis and Directed Complementation

To identify tumor maintenance genes and pathways, we applied a genome-wide, large-scale functional screening approach using retrovirus-mediated mutagenesis on a number of inducible murine solid tumor models, including a HER2-driven breast tumor model and kRAS-driven breast and lung cancer models, in which viral integration could maintain established tumors in the absence of the initiating oncogene. We identified more than 3,000 recurrent viral integration sites in a collection of about 400 tumors. Whereas some genes were targeted by viral integration in specific tumor models, others were prominently hit in all the models. For example, insertions targeting the Furin locus were detected in tumors from all three models. In such tumors, viral integrations mapped to the Furin promoter consistent with the notion that activation of this gene and/or pathway may represent a common mechanism of tumor maintenance. Using our inducible directed complementation (DC) platform, we show that introduction of a wild type FURIN cDNA can maintain primary tumors in vivo in the absence of the initial driving oncogene. The FURIN DC tumors provide a useful pre-clinical model with which we can examine the effects of FURIN antagonists on tumor maintenance. Next, we sought to extend the utility of these validated DC tumor models to drug discovery by establishing FURIN-dependent cell lines for high-throughput screening. Here we describe detailed molecular characterization of the FURIN DC tumor models as well as from the cell lines derived from these tumor models. Furthermore, FURIN DC Tumor Models as wells as cell lines serve as a unique experimental tools, with which response to novel targeted therapies and other cancer agents can be studied. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 646.

Abstract A233: Generation of in vitro and in vivo tumor models driven by insulin‐like growth factor receptor (IGF1R) and their use in the development of OSI‐906, a selective IGF1R inhibitor

The emergence of insulin‐like growth factor‐1 receptor IGF1R as an important cancer target is evidenced by the growing number of clinical trials currently underway for both small molecule inhibitors and antibody therapeutics developed against it. In preclinical studies, perturbation in IGF1R signaling has been associated with tumor growth inhibition, blockade of metastasis, and enhanced sensitivity to therapeutic agents, including cytotoxic chemotherapeutics and molecular targeted agents. Currently agents directed against IGF1R are being evaluated in clinical trials for their therapeutic utility. Given the differential dependence on IGF1R exhibited by human tumors and xenograft lines, there is a need for additional preclinical models in which the relationship between genetic context and drug response in solid tumors can be better understood in an in vivo setting. To this end, we utilized our HER2 driven inducible breast cancer model to create a panel of genetically‐engineered mouse tumors, each driven by the human IGF1R. Some of the models were also engineered to express a cognate ligand IGF2. In these models, tumors initially driven by human HER2 expression are re‐programmed by the addition of the human IGF1R cDNA upon withdrawal of the original HER2 expression. Thus, the newly introduced IGF1R‐ IGF2 cDNA functionally maintains tumor survival by re‐directing downstream signalling effectors in a process referred to as ‘Directed Complementation’ (DC). Using this approach, introduction of IGF1R strongly complemented tumor formation across the panel, whereas introduction of the ligands, either IGF1 or IGF2, alone or in combination did not. We recently showed that treatment of IGF1R/IGF2 DC tumors with OSI‐906, a potent, selective orally active inhibitor of IGF1R, resulted in tumor regression within a week of treatment, with corresponding loss of phospho‐IGF1R signaling (AACR 2009: Abstract # 2902, Lerner, et al). These results demonstrate the singular dependence of these tumors on IGF1R signaling, as well as the in vivo efficacy of the compound. Next, we sought to extend the utility of these validated tumor models to drug discovery by establishing IGF1R‐dependent cell lines for high‐throughput screening. Here we describe detailed molecular characterization of these cell lines derived from the IGF1R/IGF2 DC tumor models as well as their drug sensitivities. Importantly, we show that the IGF1R/IGF2 DC cell lines, like their parent tumors, retain activation of the pathway as well as sensitivity to OSI‐906. Therefore, these tumor models and derived cell lines provide an effective preclinical tool for the development of targeted anti‐IGF1R therapies. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A233.