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  • 1
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2011
    In:  Cancer Research Vol. 71, No. 8_Supplement ( 2011-04-15), p. LB-232-LB-232
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 71, No. 8_Supplement ( 2011-04-15), p. LB-232-LB-232
    Abstract: TRAIL (Apo2L) is a member of the Tumor Necrosis Factor Superfamily (TNF-SF) that induces apoptosis through binding to two closely related receptors, TRAIL-R1 and TRAIL-R2. Its unique ability of selective apoptosis induction in tumor cells makes TRAIL an attractive molecule for tumor therapy. APG350 is a newly designed TRAIL-receptor agonist comprising two single-chain TRAIL-receptor binding domains (each consisting of three covalently linked TRAIL protomers) that are dimerized via the Fc-part of human IgG1. APG350 has six receptor binding sites per molecule and binds to both death inducing TRAIL receptors. In vitro, APG350 shows potent apoptosis induction on a wide subset of human tumor cell-lines, on cancer stem cells and on primary tumor cells. Mechanistically its improved ability to form clusters on target cells composed of six TRAIL-receptors each, distinguishes APG350 from current clinical development candidates. Agonistic antibodies like Conatumumab or Apomab are capable to bind two receptor chains per molecule, while recombinant TRAIL (e.g. Dulanermin) binds three receptor chains per molecule. Direct in vitro comparison of APG350 with recombinant TRAIL (APG400) and a TRAIL-R2 specific agonistic monoclonal antibody revealed superior apoptosis induction capacity for APG350. Analysis of the PK-parameters in mice showed a half life of 23.1h for APG350 (1.04h for APG400) indicating a significantly improved PK in comparison to APG400. The half life of APG350 in a Cynomolgus monkey was 26.7h. Comparative treatment of mice bearing Colo205 xenograft tumors with APG350 and APG400 employing one treatment cycle with five consecutive daily intravenous injections showed a superior efficacy of APG350 with respect to tumor volume reduction and number of tumor free animals. Even mice with initially large tumors (∼600 mm3) were treated effectively with APG350. Remarkably, APG350 also showed pronounced dose dependent anti tumor efficacy on xenograft-tumors derived from colon cancer stem cells (CSC). Furthermore large CSC-derived tumors could be treated effectively and successful re-treatment of previously responding tumors demonstrated that tumors did not gain drug resistance. In a pilot experiment APG350 treatment of mice bearing a slowly growing primary rectum tumor xenograft also showed a significant tumor volume reduction. In all in vivo studies APG350 was well tolerated at doses between 0.3–100mg/kg bw in mice and doses up to 10mg/kg bw in a Cynomolgus monkey. General tolerability and potential effects on liver toxicity were assessed by co-application of APG350 together with a crosslinking antibody in mice. This treatment evoked only minor clinical signs at high doses with no relevant increase in liver enzymes. Currently two non-GLP toxicology studies, a 4-week study in mice and a dose escalation study in Cynomolgus monkeys are ongoing to confirm tolerability in vivo. 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 LB-232. doi:10.1158/1538-7445.AM2011-LB-232
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
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    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2011
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  • 2
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 71, No. 8_Supplement ( 2011-04-15), p. LB-382-LB-382
    Abstract: CD95 is a prototype death receptor that regulates the induction of apoptosis, upon binding of its ligand CD95L. Therefore, activation of the CD95L/CD95 system has been regarded an excellent target for treatment of various malignancies. In contrast to the aim of promoting CD95 activation, there is compelling evidence that CD95 is able to promote tumor growth through intracellular non-apoptotic signalling mechanisms. This mechanism has recently been described for glioblastoma, in which activation of CD95 by CD95L leads to invasive growth and glioma cell migration. This is signalled through increased activity of pivotal glioblastoma invasion-related proteases, that is matrix metalloproteinases (MMP). With this shift of paradigms, blocking of the CD95L mediated invasion of tumor cells and subsequent tumor progression may therefore be a promising approach in anti-glioma therapy. APG101 is a fusion protein, consisting of the extracellular domain of human CD95 and the Fc-region of human immunoglobulin G. Hence, it acts as a soluble CD95 receptor trapping the CD95 ligand. The presented project aims at analyzing the clinical relevance of blocking CD95 signalling, given the fact that glioma patients with upregulated CD95 expression have worse survival rates than those with intermediate expression levels. In proof-of principle experiments APG101 inhibits CD95L-mediated invasion of glioma cells. More importantly, APG101-treatment (100 mg/kg body weight) resulted in significantly prolonged survival of SMA560-tumor bearing Vm/Dk mice, less glioma cell satellites in the surrounding tissue and reduced activity of MMP. APG101 in combination with focal irradiation at 6 Gy demonstrated a remarkable reduction of tumor growth with a significantly prolonged survival compared with irradiation treatment alone and inhibition of the proinvasive properties of radiotherapy as demonstrated by magnetic resonance imaging and histology. Surprisingly, APG-101 added to the vascular endothelial growth factor receptor (VEGFR) inhibitor cediranib (AZD2171) did not increase the survival of SMA-560-tumor bearing mice as compared to cediranib alone nor did it impair the proinvasive consequences of cediranib. Our data strongly support the potential use and clinical evaluation of APG101 in combination with radiotherapy in the treatment of malignant glioma. 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 LB-382. doi:10.1158/1538-7445.AM2011-LB-382
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
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    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2011
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  • 3
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2014
    In:  Cancer Research Vol. 74, No. 19_Supplement ( 2014-10-01), p. 4986-4986
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 74, No. 19_Supplement ( 2014-10-01), p. 4986-4986
    Abstract: CD95 (APO-1/Fas) is a receptor that belongs to the Tumor Necrosis Factor Receptor Super Family (TNFRSF). Originally discovered as a death receptor inducing apoptosis upon binding to its ligand CD178 (CD95L/FasL), recent research indicates that CD95 also mediates non-apoptotic functions (e.g. liver regeneration, neuronal development, inflammation and cellular migration/invasion of tumor cells) depending on the cellular context. The potential impact on multiple cellular processes classifies the CD95 pathway as an attractive target for pharmacological interference. Apogenix developed APG101, a recombinant human fusion protein consisting of the extracellular domain of CD95 and the Fc-domain of an IgG antibody for the treatment of glioblastoma, a malignancy characterized by aggressive and invasive growth. Preclinical development activities to elucidate the mode of action of APG101 included the comparison of 3-dimensional in vitro and ex vivo models employing U87-MG and U373-MG cells on murine organotypic brain tissue cultures. Expression of CD95L and CD95 in these cells was reduced by semi-stable transfection of shRNA vectors to assess contribution of the CD95/CD95L system to invasion and proliferation of glioma cell lines and the anti-invasive effect of APG101 treatment. While knockdown of CD95 leads to death of U373-MG cells, we observed significant reduction of proliferation rates in U87-MG cells. The effect of CD95L knockdown on proliferation was only minor in U87-MG and was absent in U373-MG cells. Consistently, we found that treatment of glioma cells with APG101 had no effect on proliferation rates or cell cycle regulation of either cell line. The main effect of CD95L knockdown was a strongly reduced invasiveness of both cell lines in vitro and ex vivo. Invasiveness could be restored by exogenous addition of recombinant CD95L, and this induced invasion was inhibited in the presence of APG101. In contrast, a CD95L binding defective CD95-Fc mutant APG122 did not have an anti-invasive effect in our experimental models. We conclude that: Results obtained from the in vitro and ex vivo assay models reflect each other and are suitable to study the role of CD95 signaling in tumor cell invasion activation of CD95 on glioma cells by CD95L contributes to invasive spread of tumor cells to the surrounding brain tissue, and Apogenix drug APG101 is able to block the pro-invasive activity of CD95L. Based on these observations, an important mode of action for APG101 is inhibition of CD95 ligand induced invasion of glioma cells. Citation Format: Christian Merz, Alexander Strecker, Jaromir Sykora, Oliver Hill, Gieffers Christian, Harald Fricke, Peter Angel, Heike Peterziel. APG101 inhibits CD95-Ligand induced invasion of glioblastoma in 3D-models in vitro and ex vivo. [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 4986. doi:10.1158/1538-7445.AM2014-4986
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
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    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2014
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  • 4
    In: Molecular Cancer Therapeutics, American Association for Cancer Research (AACR), Vol. 12, No. 12 ( 2013-12-01), p. 2735-2747
    Abstract: Cancer cells can be specifically driven into apoptosis by activating Death-receptor-4 (DR4; TRAIL-R1) and/or Death-receptor-5 (DR5; TRAIL-R2). Albeit showing promising preclinical efficacy, first-generation protein therapeutics addressing this pathway, especially agonistic anti-DR4/DR5-monoclonal antibodies, have not been clinically successful to date. Due to their bivalent binding mode, effective apoptosis induction by agonistic TRAIL-R antibodies is achieved only upon additional events leading to antibody-multimer formation. The binding of these multimers to their target subsequently leads to effective receptor-clustering on cancer cells. The research results presented here report on a new class of TRAIL-receptor agonists overcoming this intrinsic limitation observed for antibodies in general. The main feature of these agonists is a TRAIL-mimic consisting of three TRAIL-protomer subsequences combined in one polypeptide chain, termed the single-chain TRAIL-receptor–binding domain (scTRAIL-RBD). In the active compounds, two scTRAIL-RBDs with three receptor binding sites each are brought molecularly in close proximity resulting in a fusion protein with a hexavalent binding mode. In the case of APG350—the prototype of this engineering concept—this is achieved by fusing the Fc-part of a human immunoglobulin G1 (IgG1)-mutein C-terminally to the scTRAIL–RBD polypeptide, thereby creating six receptor binding sites per drug molecule. In vitro, APG350 is a potent inducer of apoptosis on human tumor cell lines and primary tumor cells. In vivo, treatment of mice bearing Colo205-xenograft tumors with APG350 showed a dose-dependent antitumor efficacy. By dedicated muteins, we confirmed that the observed in vivo efficacy of the hexavalent scTRAIL–RBD fusion proteins is—in contrast to agonistic antibodies—independent of FcγR-based cross-linking events. Mol Cancer Ther; 12(12); 2735–47. ©2013 AACR.
    Type of Medium: Online Resource
    ISSN: 1535-7163 , 1538-8514
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2013
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  • 5
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 72, No. 8_Supplement ( 2012-04-15), p. 3856-3856
    Abstract: APG350 is a TRAIL-receptor (TRAIL-R) agonist comprising two single-chain TRAIL-R binding domains (scTRAIL-RBD) that are dimerized via the Fc-part of a human IgG1-mutein thereby creating six receptor binding sites per molecule. This improved ability to form clusters on target cells composed of six TRAIL-Rs each, distinguishes APG350 from current clinical development candidates. In vitro, comparison of APG350 with recombinant APO2L/TRAIL and a TRAIL-R2 specific agonistic antibody revealed superior apoptosis induction for APG350 on primary and established human tumor cell-lines. Treatment of mice bearing Colo205 xenograft tumors with APG350, APO2L/TRAIL or an agonistic TRAIL-R2 specific antibody showed superior anti-tumor efficacy for APG350. Pronounced anti tumor efficacy was also shown on colon cancer stem cell (CSC) derived xenografts and successful APG350 re-treatment of relapsed CSC derived tumors demonstrated that tumors did not develop drug resistance. For most agonistic TRAIL-R antibodies effective apoptosis induction is achieved only upon additional cross-linking. SEC-based fractionation of a TRAIL-R2 specific agonistic antibody indicates a small amount of multimerized antibody that showed efficient apoptosis induction in vitro. However, the respective monomeric antibody showed poor apoptosis induction in vitro that could be enhanced upon cross-linking. In contrast apoptosis induction by APG350 was only marginally enhanced by cross-linking. Although monomeric agonistic TRAIL-R antibodies are poor apoptosis inducers in vitro, they show efficient apoptosis induction on xenograft tumors in vivo. A likely explanation for this difference is given by a recent publication showing that anti-tumor efficacy of an agonistic TRAIL-R2 specific antibody (Drozitumab) depends on cross-linking by Fcα-receptors (FcαR) in vivo. These data suggest that FcαR cross-linking might be a common requirement for the anti-tumor efficacy of agonistic TRAIL-R antibodies. To exclude that in vivo efficacy of APG350 depends on cross-linking by FcαRs we designed APG350-muteins with strongly reduced (APG808) or lacking FcαR binding (APG780). Side by side comparison of APG808, APG780 and APG350 in mice bearing Colo205-derived xenograft tumors showed identical anti-tumor efficacy for all respective proteins. Given that APG780 cannot bind to FcαRs these results suggest that the anti-tumor efficacy of APG808, APG780 and APG350 is solely based on the unique construction principle of the dimerized scTRAIL-RBD. APG350 induces superior clustering of TRAIL-Rs that in contrast to agonistic TRAIL-R antibodies does not require cross-linking via FcαRs for its potent anti-tumor efficacy. APG350 based dimerized scTRAIL-RBD formats may therefore have the capacity to bridge the current gap seen between preclinical and clinical efficacy for agonistic TRAIL-R specific antibodies. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3856. doi:1538-7445.AM2012-3856
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
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    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2012
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  • 6
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2010
    In:  Cancer Research Vol. 70, No. 8_Supplement ( 2010-04-15), p. LB-273-LB-273
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 70, No. 8_Supplement ( 2010-04-15), p. LB-273-LB-273
    Abstract: CD95 (APO-1/FAS) is a receptor that belongs to the Tumor Necrosis Factor Super Family (TNFSF). Binding of the cognate ligand (CD95L) to CD95 triggers intracellular signaling, ultimately leading to apoptotic cell death. Recent research indicates that CD95 depending on the tissue and the conditions also mediates diverse non-apoptotic functions (e.g. liver regeneration, neuronal development, inflammation and cellular migration/invasion of tumor cells). The potential impact on multiple cellular processes classifies the CD95 pathway as an attractive target for pharmacological interference. Apogenix developed APG101 a human fusion protein consisting of the extracellular domain of the CD95 receptor and the Fc-domain of an IgG antibody. APG101 can be used for the treatment of patho-physiological conditions showing an excess of CD95 induced apoptosis (e.g. acute Graft versus Host Disease, [GvHD] ) and for malignancies that depend on CD95 regulated cell migration/invasion (e.g. cancer). Comprehensive, preclinical studies have demonstrated the therapeutic potential of APG101 in Glioblastoma Multiforme (GBM) and aGvHD. GBM is a malignant astrocytic tumor that is highly resistant to radiation and chemotherapy induced apoptosis. A major reason for the particular poor prognosis of GBM is the diffuse invasive growth of infiltrating tumor cell into the surrounding brain. These infiltrating tumor cells evade surgery and are a major cause for tumor relapse. For this reason treatment regimens inhibiting the invasive phenotype should be beneficial for the treatment of GBM. It was shown recently that binding of CD95L to its cognate receptor is an important trigger for the invasive growth of glioblastoma cells and that inhibition of CD95 signaling with neutralizing antibodies abolished the invasion of glioblastoma in vitro and in vivo. Data presented here indicate that APG101 is capable to interfere with the invasive phenotype of glioblastoma cell lines in vitro. Furthermore APG101 effectively reduced the migration of invading tumor cells in a syngeneic mouse model of intracranial GBM (SMA-model). In a modified experimental setup the SMA-mouse model was additionally tested for the efficacy of a combinatorial treatment of APG101 and irradiation. These experiments revealed that a combination of APG101 and sub-lethal irradiation inhibits the invasive growth of GBM cells in vivo, whereas radiation alone had no effect on invasive growth. Detailed analysis of the treatment groups indicated that the combination of APG101 and sub-lethal irradiation prevents formation of satellite tumors, an effect that could not be observed in the control groups. Based on the preclinical data set presented, APG101 is currently tested in a clinical Phase II for the treatment of GBM. 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 LB-273.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
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    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2010
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