Zhigang Weng

GP369, an FGFR2-IIIb specific antibody, exhibits potent antitumor activity against human cancers driven by activated FGFR2 signaling

Dysregulated fibroblast growth factor (FGF) signaling has been implicated in the pathogenesis of human cancers. Aberrant activation of FGF receptor 2 (FGFR2) signaling, through overexpression of FGFR2 and/or its ligands, mutations, and receptor amplification, has been found in a variety of human tumors. We generated monoclonal antibodies against the extracellular ligand-binding domain of FGFR2 to address the role of FGFR2 in tumorigenesis and to explore the potential of FGFR2 as a novel therapeutic target. We surveyed a broad panel of human cancer cell lines for the dysregulation of FGFR2 signaling and discovered that breast and gastric cancer cell lines harboring FGFR2 amplification predominantly express the IIIb isoform of the receptor. Therefore, we used an FGFR2-IIIb-specific antibody, GP369, to investigate the importance of FGFR2 signaling in vitro and in vivo. GP369 specifically and potently suppressed ligand-induced phosphorylation of FGFR2-IIIb and downstream signaling, as well as FGFR2-driven proliferation in vitro. The administration of GP369 in mice significantly inhibited the growth of human cancer xenografts harboring activated FGFR2 signaling. Our findings support the hypothesis that dysregulated FGFR2 signaling is one of the critical oncogenic pathways involved in the initiation and/or maintenance of tumors. Cancer patients with aberrantly activated/amplified FGFR2 signaling could potentially benefit from therapeutic intervention with FGFR2-targeting antibodies.

Neuregulin 1 Expression Is a Predictive Biomarker for Response to AV-203, an ERBB3 Inhibitory Antibody, in Human Tumor Models

Purpose: ERBB3 is overexpressed in a broad spectrum of human cancers, and its aberrant activation is associated with tumor pathogenesis and therapeutic resistance to various anticancer agents. Neuregulin 1 (NRG1) is the predominant ligand for ERBB3 and can promote the heterodimerization of ERBB3 with other ERBB family members, resulting in activation of multiple intracellular signaling pathways. AV-203 is a humanized IgG1/κ ERBB3 inhibitory antibody that completed a first-in-human phase I clinical trial in patients with advanced solid tumors. The purpose of this preclinical study was to identify potential biomarker(s) that may predict response to AV-203 treatment in the clinic. Experimental Design: We conducted in vivo efficacy studies using a broad panel of xenograft models representing a wide variety of human cancers. To identify biomarkers that can predict response to AV-203, the relationship between tumor growth inhibition (TGI) by AV-203 and the expression levels of ERBB3 and NRG1 were evaluated in these tumor models. Results: A significant correlation was observed between the levels of NRG1 expression and TGI by AV-203. In contrast, TGI was not correlated with ERBB3 expression. The correlation between the levels of NRG1 expression in tumors and their response to ERBB3 inhibition by AV-203 was further validated using patient-derived tumor explant models. Conclusions: NRG1 is a promising biomarker that can predict response to ERBB3 inhibition by AV-203 in preclinical human cancer models. NRG1 warrants further clinical evaluation and validation as a potential predictive biomarker of response to AV-203. Clin Cancer Res; 21(5); 1106–14. ©2014 AACR.

MAP3K11/GDF15 axis is a critical driver of cancer cachexia

Cancer associated cachexia affects the majority of cancer patients during the course of the disease and thought to be directly responsible for about a quarter of all cancer deaths. Current evidence suggests that a pro‐inflammatory state may be associated with this syndrome although the molecular mechanisms responsible for the development of cachexia are poorly understood. The purpose of this work was the identification of key drivers of cancer cachexia that could provide a potential point of intervention for the treatment and/or prevention of this syndrome.

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 2011: Feasibility of serum proteomic companion diagnostic (CDx) test development on the microflex LT platform

Clinical oncology assays using mass spectrometry have exclusively been run on instrument platforms designed for use in research laboratories. Here, we report on the use of a bench-top MALDI-TOF mass spectrometer (MS) to run a serum proteomic Laboratory Developed Test (LDT), VeriStrat®. A number of previous studies have shown that this assay measures a serum proteomic fingerprint using MALDI-TOF MS which, following spectral acquisition and data processing, classifies advanced non-small cell lung cancer (NSCLC) patients into treatment categories. An extension of VeriStrat, BDX004, is currently under development as part of a global, randomized, double-blind Phase 2 clinical study, FOCAL. BDX004 will be used prospectively to select previously untreated, EGFR mutation-positive patients with advanced NSCLC to receive one of two treatments: (1) the combination of ficlatuzumab (a humanized monoclonal antibody against hepatocyte growth factor) and an EGFR tyrosine kinase inhibitor (TKI), or (2) an EGFR TKI with placebo. For the development of BDX004 as a companion diagnostic (CDx), we have included the microflex™ LT (LT), a component of Bruker9s MALDI Biotyper CA system, which was granted FDA clearance for the identification of Gram negative bacteria. In the present study, we evaluated the LT platform through comparative studies with other MALDI-TOF instruments (autoflex™ III and autoflex SPEED) utilizing samples from patients previously diagnosed with NSCLC. In summary, we found that under common laboratory procedures the LT produces results equivalent to research grade MALDI-TOF MS instrumentation. In initial studies, the microflex LT showed similar resolution (R > 600 at 6632.1 m/z) and sensitivity (S/N ≥ 50 with 500 fmoles BSA in 100 laser shots) performance parameters as the autoflex series research instruments (R > 800 at 6632.1 m/z and S/N ≥ 50 with 500 fmoles BSA in 250 laser shots). The LT was qualified with several independent sample sets [n = 4 (8 replicates; 2000 spectra/replicate); n = 67 (3 replicates; 2000 spectra/replicate) and n = 20 (3 replicates; 2000 spectra/replicate)]. In these studies, the LT achieved 100%, >97%, and 100% concordance with reference data sets previously acquired on the autoflex platforms. As expected, due to the lower laser repetition rate of the LT9s nitrogen laser, the acquisition speed was slower on the LT as compared to the autoflex instruments by a factor of two. However, the slower acquisition speed is partially compensated for with increased sensitivity, which is particularly evident in the reference sample mass spectra which have signal-to-noise ratios ∼1.5 greater than those acquired on the autoflex platform. Based on these results, the microflex LT appears to be suitable for measurement of serum proteomic profiles in NSCLC and suggests that the inclusion of the microflex LT in CDx test development has the potential to expand the utility of MALDI-based testing in the clinic. Citation Format: Nicholas Dupuis, Jamie Chang, Maximillian Steers, Zhigang Weng, Jeno Gyuris, Gary Pestano. Feasibility of serum proteomic companion diagnostic (CDx) test development on the microflex LT platform. [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 2011. doi:10.1158/1538-7445.AM2015-2011

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 4586: Essential role of fibroblast growth factor receptor 2 (FGFR2) in tumorigenesis of human cancers with activated FGFR2 signaling demonstrated by functional blocking antibodies

Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL Aberrant activation of fibroblast growth factor receptor 2 (FGFR2) signaling, through overexpression of FGFR2 and/or its ligands, mutations, and receptor amplification have been found in a variety of human tumors. We generated monoclonal antibodies against the extracellular ligand binding domain of FGFR2 to address the role of FGFR2 in tumorigenesis and to explore the potential of FGFR2 as a novel therapeutic target. We identified a broad panel of human cancer cell lines with dysregulated FGFR2 signaling and examined the sensitivity of these human cell lines to monoclonal antibodies specifically targeting FGFR2. These FGFR2 antibodies potently suppressed ligand-induced phosphorylation of FGFR2 and downstream signaling, as well as cell proliferation in vitro. The administration of FGFR2 monoclonal antibodies in mice significantly inhibited the growth of human cancer xenografts harboring activated FGFR2 signaling. Our findings support that dysregulated FGFR2 signaling is one of the critical oncogenic pathways involved in the initiation and/or maintenance of tumors. Cancer patients with aberrantly activated/amplified FGFR2 signaling could potentially benefit from therapeutic intervention with FGFR2-targeting antibodies. 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 4586. doi:10.1158/1538-7445.AM2011-4586