Search

Purpose: To explore the role of TWEAK in tumor growth and antitumor immune response and the activity and mechanism of RG7212, an antagonistic anti-TWEAK antibody, in tumor models.Experimental Design: TWEAK-induced signaling and gene expression were explored in tumor cell lines and inhibition of these effects and antitumor efficacy with RG7212 treatment was assessed in human tumor xenograft-, patient-derived xenograft, and syngeneic tumor models and phase I patients. Genetic features correlated with antitumor activity were characterized.Results: In tumor cell lines, TWEAK induces proliferation, survival, and NF-κB signaling and gene expression that promote tumor growth and suppress antitumor immune responses. TWEAK-inducible CD274, CCL2, CXCL-10 and -11 modulate T-cell and monocyte recruitment, T-cell activation, and macrophage differentiation. These factors and TWEAK-induced signaling were decreased, and tumor, blood, and spleen immune cell composition was altered with RG7212 treatment in mice. RG7212 inhibits tumor growth in vivo in models with TWEAK receptor, Fn14, expression, and markers of pathway activation. In phase I testing, signs of tumor shrinkage and stable disease were observed without dose-limiting toxicity. In a patient with advanced, Fn14-positive, malignant melanoma with evidence of tumor regression, proliferation markers were dramatically reduced, tumor T-cell infiltration increased, and tumor macrophage content decreased. Antitumor activity, a lack of toxicity in humans and animals and no evidence of antagonism with standard of care or targeted agents in mice, suggests that RG7212 is a promising agent for use in combination therapies in patients with Fn14-positive tumors. Clin Cancer Res; 19(20); 5686–98. ©2013 AACR.

XLS file, 33K, Summary of RG7212 monotherapy and combination antitumor efficacy.

PDF file, 306K, RG7212 antitumor efficacy and characterization of tumor models used to assess RG7212 antitumor efficacy.

PDF file, 771K, TWEAK promotes proliferation and survival signaling with minimal effect on cell viability.

PDF file, 132K.

XLS file, 193K, Sorted Affymetrix gene array data.

PDF file, 29K, Lead antibodies have identical binding properties and neutralizing activities.

PDF file, 176K, Assessment of baseline gene expression in RG7212 responders and non-responders in qPCR array.

PDF file - 3450KB, Colocalization of CD8 T-cells with PD-L1 expression.

PDF file - 50KB

Tumor-associated antigens have emerged as important immunotherapeutic targets in the fight against cancer. Germline tumor antigens, such as WT1, Wilms’ tumor gene 1, are overexpressed in many human malignancies but have low expression in somatic tissues. Recent vaccination approaches to target WT1 have been hampered by poor in vivo immune potency, likely due to the conserved self-antigen nature of WT1. In this study, we use a novel synthetic micro-consensus SynCon DNA vaccine approach with the goal of breaking tolerance and increasing vaccine immune potency. This approach induced new, neo-antigen-like responses that were superior to those induced by native WT1 DNA immunogens for driving T cell immunity and breaking tolerance. Non-human primates (NHPs) vaccinated with SynCon WT1 antigens elicited immune responses against native rhesus WT1 peptides. When delivered by electroporation (EP) in mice, SynCon-based WT1 constructs elicited strong CD4 and CD8 T cell responses (including IFN-γ, CD107a, and TNF-α) to both native and consensus peptides. In addition, SynCon WT1 vaccine-induced antibodies recognized native WT1 in vitro. Vaccination with the SynCon WT1 immunogens was capable of slowing tumor growth in therapeutic models in vivo. These data support the further study of synthetic consensus DNA vaccines for breaking tolerance to important germline antigens.

Purpose: To explore the role of TWEAK in tumor growth and antitumor immune response and the activity and mechanism of RG7212, an antagonistic anti-TWEAK antibody, in tumor models. Experimental Design: TWEAK-induced signaling and gene expression were explored in tumor cell lines and inhibition of these effects and antitumor efficacy with RG7212 treatment was assessed in human tumor xenograft-, patient-derived xenograft, and syngeneic tumor models and phase I patients. Genetic features correlated with antitumor activity were characterized. Results: In tumor cell lines, TWEAK induces proliferation, survival, and NF-κB signaling and gene expression that promote tumor growth and suppress antitumor immune responses. TWEAK-inducible CD274, CCL2, CXCL-10 and -11 modulate T-cell and monocyte recruitment, T-cell activation, and macrophage differentiation. These factors and TWEAK-induced signaling were decreased, and tumor, blood, and spleen immune cell composition was altered with RG7212 treatment in mice. RG7212 inhibits tumor growth in vivo in models with TWEAK receptor, Fn14, expression, and markers of pathway activation. In phase I testing, signs of tumor shrinkage and stable disease were observed without dose-limiting toxicity. In a patient with advanced, Fn14-positive, malignant melanoma with evidence of tumor regression, proliferation markers were dramatically reduced, tumor T-cell infiltration increased, and tumor macrophage content decreased. Antitumor activity, a lack of toxicity in humans and animals and no evidence of antagonism with standard of care or targeted agents in mice, suggests that RG7212 is a promising agent for use in combination therapies in patients with Fn14-positive tumors. Clin Cancer Res; 19(20); 5686–98. ©2013 AACR.

With the recent FDA approvals of pembrolizumab and nivolumab, and a host of additional immunomodulatory agents entering clinical development each year, the field of cancer immunotherapy is changing rapidly. Strategies that can assist researchers in choosing the most promising drugs and drug combinations to move forward through clinical development are badly needed in order to reduce the likelihood of late-stage clinical trial failures. On October 5, 2014, the Cancer Immunotherapy Consortium of the Cancer Research Institute, a collaborative think tank composed of stakeholders from academia, industry, regulatory agencies, and patient interest groups, met to discuss strategies for de-risking immunotherapy development, with a focus on integrating preclinical and clinical studies, and conducting smarter early-phase trials, particularly for combination therapies. Several recommendations were made, including making better use of clinical data to inform preclinical research, obtaining adequate tissues for biomarker studies, and choosing appropriate clinical trial endpoints to identify promising drug candidates and combinations in nonrandomized early-phase trials. Cancer Immunol Res; 4(4); 279–88. ©2016 AACR.

Biomarker studies have shown that expression of the T-cell coregulatory ligand PDL1 on tumor cells correlates with clinical responsiveness to the PD1 antibody nivolumab. Here, we report the findings of a preclinical cancer vaccine study demonstrating vaccine-dependent PDL1 upregulation in the tumor microenvironment. We formulated an IFNγ-inducing cancer vaccine called TEGVAX that combined GM-CSF and multiple Toll-like receptor agonists to increase the number of activated dendritic cells. Treatment of established tumors with TEGVAX retarded tumor growth in a manner associated with enhanced systemic antitumor immunity. Unexpectedly, TEGVAX also upregulated PDL1 expression in the tumor microenvironment, possibly explaining why tumors were not eliminated completely. In support of this likelihood, PDL1 upregulation in this setting relied upon IFNγ-expressing tumor-infiltrating CD4+ and CD8+ T cells and administration of a PD1-blocking antibody with TEGVAX elicited complete regression of established tumors. Taken together, our findings provide a mechanistic rationale to combine IFNγ-inducing cancer vaccines with immune checkpoint blockade. Cancer Res; 74(15); 4042–52. ©2014 AACR.

Much evidence now exists that tumors possess specific antigens recognizable by T cells. The goal of immunotherapy is to break tolerance to these antigens while preserving self-tolerance. Recently, newer approaches have been developed in animal systems that modify tumor cells genetically so that they express new antigens or secrete certain cytokines. Engineering tumor cells to secrete cytokines in a paracrine fashion can induce powerful local cytokine effects which, in addition to inducing local inflammation, can alter the presentation of tumor antigens or the activation of tumor-antigen-specific T lymphocytes, resulting in systemic antitumor immunity.