scholarly journals Targeting C5aR1 Increases the Therapeutic Window of Radiotherapy

2020 ◽  
Author(s):  
Monica M. Olcina ◽  
Melemenidis Stavros ◽  
Dhanya K. Nambiar ◽  
Ryan K. Kim ◽  
Kerriann M. Casey ◽  
...  
Keyword(s):  
T Cell ◽  
Tumor Cells ◽  
Normal Tissue ◽  
Standard Of Care ◽  
Innate Immune ◽  
Therapeutic Window ◽  
Functional Markers ◽  
Current Standard ◽  
T Cell Infiltration ◽  
Radiation Induced

AbstractEngaging innate immune pathways is emerging as a productive way of achieving durable anti-tumor responses. However, systemic administration of these therapies can result in toxicity, deemed to be particularly problematic when combined with current standard-of-care cytotoxic treatments such as radiotherapy. Increasing the therapeutic window of radiotherapy may be achieved by using targeted therapies, however, few pre-clinical studies investigate both tumor and normal tissue responses in detail. Here we show that targeting innate immune receptor C5aR1 improves tumor radiation response while reducing radiation-induced normal tissue toxicity, thereby increasing the therapeutic window. Genetically or pharmacologically targeting C5aR1 increases both IL-10 expression in the small intestine and IL-10 secretion by tumor cells. Increased IL-10 attenuates RelA phosphorylation and increases apoptosis in tumor cells, leading to improved radiation responses in murine models. Of note, these radiosensitizing effects are tumor-specific since, in the gastrointestinal tract, targeting C5aR1 instead results in decreased crypt cell apoptosis reduced signs of histological damage and improved survival following total abdominal irradiation in mice. Furthermore, the potent and orally active C5aR1 inhibitor, PMX205, improves tumor radiation responses even in a context of reduced/absent CD8+ T cell infiltration. These data indicate that PMX205 can modulate cancer-cell intrinsic functions to potentiate anti-tumor radiation responses even in tumors displaying features of T-cell deficiency or exclusion. Finally, using a preclinical murine model allowing the simultaneous assessment of tumor and normal tissue radiation responses, we show that PMX205 treatment reduces histological and functional markers of small-bowel toxicity while affording a positive tumor response. Our data, therefore, suggest that targeting C5aR1 could be a promising approach for increasing the therapeutic window of radiotherapy.

scholarly journals 121 ICAM-1-specific affinity tuned CAR T cells expressing SSTR2 for real-time imaging

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A130-A130
Author(s):  
Jingmei Hsu ◽  
Eric von Hofe ◽  
Michael Hsu ◽  
Koen Van Besien ◽  
Thomas Fahey ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Phase I ◽  
Tumor Cells ◽  
Somatostatin Receptor ◽  
Laboratory Animals ◽  
Therapeutic Window ◽  
Car T Cells ◽  
Car T

BackgroundThe use of CAR T cells for solid tumors has a number of challenges, such as lack of tumor-specific targets, CAR T cell exhaustion, and the immunosuppressive tumor microenvironment. To address these challenges, AffyImmune has developed technologies to affinity tune and track CAR T cells in patients. The targeting moiety is affinity tuned to preferentially bind to tumor cells overexpressing the target while leaving normal cells with low basal levels untouched, thereby increasing the therapeutic window and allowing for more physiological T cell killing. The CAR T cells are designed to express SSTR2 (somatostatin receptor 2), which allows for the tracking of CAR T cells in vivo via PET/CT scan using FDA-approved DOTATATE.MethodsAIC100 was generated by affinity tuning the I-domain of LFA-1, the physiological ligand to ICAM-1. Various mutants with 106-fold difference in affinity were evaluated for affinity. This allowed structure activity relationships to be conducted using CAR T cells expressing the various affinity mutants against targets with varying antigen densities. The variant with micromolar affinity was clearly the most effective in non-clinical animal models. AIC100 is currently being evaluated to assess safety, CAR T expansion, tumor localization, and preliminary activity in patients with advanced thyroid cancer in a phase I study (NCT04420754). Our study uses a modified toxicity probability interval design with three dosage groups of 10 x 106, 100 x 106, and 500 x 106 cells.ResultsPreclinical studies demonstrated greater in vivo anti-tumor activity and safety with lower affinity CAR T cells. A single dose of AIC100 resulted in tumor elimination and significantly improved survival of animals. AIC100 activity was confirmed in other high ICAM-1 tumor models including breast, gastric, and multiple myeloma. In a Phase I patient given 10-million CAR T cells, near synchronous imaging of FDG and DOTATATE revealed preliminary evidence of transient CAR T expansion and tumor reduction at multiple tumor lesions, with the peak of CAR T density coinciding with the spike in CAR T numbers in blood.ConclusionsWe have developed affinity tuned CAR T cells designed to selectively target ICAM-1 overexpressing tumor cells and to spatiotemporally image CAR T cells. Near-synchronous FDG and DOTATATE scans will enhance patient safety by early detection of off-tumor CAR T activity and validation of tumor response. We anticipate that our ‘tune and track’ technology will be widely applicable to developing potent yet safe CAR T cells against hard-to-treat solid cancers.Trial RegistrationNCT04420754Ethics ApprovalIRB number19-12021154IACUC (animal welfare): All animal experiments were performed in accordance with the National Institute of Health’s Guide for the Care and Use of Laboratory Animals. Animal handling protocols were approved by the Institutional Laboratory Animal Use and Care Committee of Weill Cornell Medicine (Permit Number: 2012–0063).

scholarly journals Effective Targeting of PRAME-Positive Tumors with Bispecific T Cell-Engaging Receptor (TCER®) Molecules

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3368-3368
Author(s):  
Sebastian Bunk ◽  
Martin Hofmann ◽  
Felix Unverdorben ◽  
Meike Hutt ◽  
Gabriele Pszolla ◽  
...  
Keyword(s):  
T Cell ◽  
Tumor Cells ◽  
Half Life ◽  
Normal Tissue ◽  
Malignant Diseases ◽  
Proof Of Concept ◽  
Employment Equity ◽  
Target Peptide ◽  
Equity Ownership ◽  
Nog Mice

T cell receptors (TCRs) naturally recognize human leukocyte antigen (HLA)-bound peptides derived from foreign and endogenous proteins regardless of their extracellular or intracellular location. Preferentially expressed antigen in melanoma (PRAME) has been shown to be expressed at high levels in a variety of cancer cells while being absent or present only at very low levels in normal adult tissues except testis. In contrast to most other cancer/testis antigens, PRAME is expressed not only in solid tumors but also in leukemia and myeloma cells. Immunotherapy with bispecific T cell engagers has emerged as a novel and promising treatment modality for malignant diseases, however, antibody-based approaches (ie. blinatumomab) are restricted to few surface antigens such as CD19 or BCMA. Immatics has developed bispecific T cell-engaging receptors (TCER®) that are fusion proteins consisting of an affinity-maturated TCR and a humanized T cell-recruiting antibody with an effector function-silenced IgG1 Fc part. TCER® molecules confer extended half-life together with antibody-like stability and manufacturability characteristics. The molecular design allows for effective redirection of T cells towards target peptide-HLA selectively expressed in tumor tissues. Here we present proof-of-concept data from a TCER® program targeting a PRAME-derived peptide bound to HLA-A*02:01. We confirmed the abundant presence of the target peptide-HLA in several cancer indications and its absence in relevant human normal tissues by using the XPRESIDENT® target discovery engine, which combines quantitative mass spectrometry, transcriptomics and bioinformatics. Yeast surface display technology was used to maturate the stability and affinity of a parental human TCR recognizing PRAME with high functional avidity and specificity. During maturation we applied XPRESIDENT®-guided off-target toxicity screening, incorporating the world's largest normal tissue immunopeptidome database, to deselect cross-reactive candidate TCRs. The maturated TCRs were engineered into the TCER® scaffold and production in Chinese hamster ovary (CHO) cells generated highly stable molecules with low tendency for aggregation as confirmed during stress studies. Following TCR maturation, the TCER® molecules exhibited an up to 10,000-fold increased binding affinity towards PRAME when compared to the parental TCR. The high affinity correlated with potent in vitro anti-tumor activity requiring only low picomolar concentrations of TCER® molecules to induce half-maximal lysis of tumor cells expressing the target at physiological levels. Furthermore, using a tumor xenograft model in immunodeficient NOG mice, we could demonstrate significant growth inhibition of established tumors upon intravenous injection of TCER® molecules. Pharmacokinetic profiling in NOG mice determined a terminal half-life of more than 4 days, compatible with a once weekly dosing regimen in patients. For the safety assessment, we measured killing of more than 20 different human normal tissue cell types derived from high risk organs. Notably, we could confirm a favorable safety window for selected TCER® molecules, which induced killing of most normal tissue cells only at significantly higher concentrations than required for killing of tumor cells. To further support safety of TCER® molecules, we also performed a comprehensive characterization of potential off-target peptides selected from the XPRESIDENT® normal tissue database based on its high similarity to the sequence of the target peptide or based on data from alternative screening approaches. In summary, the efficacy, safety and manufacturability data to be presented provide preclinical proof-of-concept for a novel bispecific T cell-engaging receptor (TCER®) molecule targeting PRAME for treatment of various malignant diseases. Disclosures Bunk: Immatics: Employment. Hofmann:Immatics: Employment. Unverdorben:Immatics: Employment. Hutt:Immatics: Employment. Pszolla:Immatics: Employment. Schwöbel:Immatics: Employment. Wagner:Immatics: Employment. Yousef:Immatics: Employment. Schuster:Immatics: Employment. Missel:Immatics: Employment. Schoor:Immatics: Employment. Weinschenk:Immatics: Employment, Equity Ownership. Singh-Jasuja:Immatics: Employment, Equity Ownership. Maurer:Immatics: Employment. Reinhardt:Immatics: Employment, Equity Ownership.

scholarly journals Salmonella Breaks Tumor Immune Tolerance by Downregulating Tumor Programmed Death-Ligand 1 Expression

Cancers ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 57
Author(s):  
Man-Chin Chen ◽  
Christian Ronquillo Pangilinan ◽  
Che-Hsin Lee
Keyword(s):  
T Cell ◽  
Tumor Growth ◽  
Tumor Cells ◽  
Immune Checkpoint ◽  
Immune Escape ◽  
Cell Infiltration ◽  
Tumor Immune Escape ◽  
Programmed Death Ligand 1 ◽  
T Cell Infiltration ◽  
Programmed Death

Immunotherapy is becoming a popular treatment modality in combat against cancer, one of the world’s leading health problems. While tumor cells influence host immunity via expressing immune inhibitory signaling proteins, some bacteria possess immunomodulatory activities that counter the symptoms of tumors. The accumulation of Salmonella in tumor sites influences tumor protein expression, resulting in T cell infiltration. However, the molecular mechanism by which Salmonella activates T cells remains elusive. Many tumors have been reported to have high expressions of programmed death-ligand 1 (PD-L1), which is an important immune checkpoint molecule involved in tumor immune escape. In this study, Salmonella reduced the expression of PD-L1 in tumor cells. The expression levels of phospho-protein kinase B (P-AKT), phospho-mammalian targets of rapamycin (P-mTOR), and the phospho-p70 ribosomal s6 kinase (P-p70s6K) pathway were revealed to be involved in the Salmonella-mediated downregulation of PD-L1. In a tumor-T cell coculture system, Salmonella increased T cell number and reduced T cell apoptosis. Systemic administration of Salmonella reduced the expressions of PD-L-1 in tumor-bearing mice. In addition, tumor growth was significantly inhibited along with an enhanced T cell infiltration following Salmonella treatment. These findings suggest that Salmonella acts upon the immune checkpoint, primarily PD-L1, to incapacitate protumor effects and thereby inhibit tumor growth.

Co-inhibition of the TGF-β pathway and the PD-L1 checkpoint by pH-responsive clustered nanoparticles for pancreatic cancer microenvironment regulation and anti-tumor immunotherapy

2020 ◽  
Vol 8 (18) ◽  
pp. 5121-5132 ◽  
Author(s):  
Yang Wang ◽  
Zhuxin Gao ◽  
Xiaojiao Du ◽  
Senbiao Chen ◽  
Wangcheng Zhang ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
T Cell ◽  
Tumor Cells ◽  
Tumor Immunotherapy ◽  
Cell Infiltration ◽  
Cancer Microenvironment ◽  
Ph Responsive ◽  
T Cell Infiltration

LYiClustersiPD-L1 could deliver LY2157299 to PSCs and release PAMAM/siPD-L1 to penetrate into tumors and target tumor cells. On synergistic therapy of both, enhanced CD8+ T cell infiltration and cytotoxicity were expected.

scholarly journals High-Throughput Screening for Positive Allosteric Modulators Identified Potential Therapeutics against Acetylcholinesterase Inhibition

2015 ◽  
Vol 20 (9) ◽  
pp. 1142-1149 ◽  
Author(s):  
Richard R. Chapleau ◽  
Craig A. McElroy ◽  
Christopher D. Ruark ◽  
Emily J. Fleming ◽  
Amy B. Ghering ◽  
...  
Keyword(s):  
Side Effects ◽  
High Throughput ◽  
High Throughput Screening ◽  
Standard Of Care ◽  
Acetylcholinesterase Inhibition ◽  
Therapeutic Window ◽  
Ache Inhibitor ◽  
Allosteric Modulators ◽  
Current Standard ◽  
Positive Allosteric Modulators

The current standard of care for treatment of organophosphate (OP) poisoning includes pretreatment with the weak reversible acetylcholinesterase (AChE) inhibitor pyridostigmine bromide. Because this drug is an AChE inhibitor, similar side effects exist as with OP poisoning. In an attempt to provide a therapeutic capable of mitigating AChE inhibition without such side effects, high-throughput screening was performed to identify a compound capable of increasing the catalytic activity of AChE. Herein, two such novel positive allosteric modulators (PAMs) of AChE are presented. These PAMs increase AChE activity threefold, but they fail to upshift the apparent IC50 of a variety of OPs. Further development and optimization of these compounds may lead to pre- and/or postexposure therapeutics with broad-spectrum efficacy against pesticide and nerve agent poisoning. In addition, they could be used to complement the current therapeutic standard of care to increase the activity of uninhibited AChE, potentially increasing the efficacy of current therapeutics in addition to altering the therapeutic window.

scholarly journals SKIL facilitates tumorigenesis and immune escape of NSCLC via upregulating TAZ/autophagy axis

2020 ◽  
Vol 11 (12) ◽  
Author(s):  
Fang Ma ◽  
Meng-Ge Ding ◽  
Yi-Yu Lei ◽  
Li-Hua Luo ◽  
Shun Jiang ◽  
...  
Keyword(s):  
T Cell ◽  
Western Blot ◽  
Quantitative Pcr ◽  
Normal Tissue ◽  
Immune Escape ◽  
Cell Infiltration ◽  
Adjacent Normal Tissue ◽  
Mice Model ◽  
T Cell Infiltration ◽  
Sting Pathway

AbstractImmune escape is an important mechanism in tumorigenesis. The aim of this study was to investigate roles of SKIL in tumorigenesis and immune escape of non-small-cell lung cancer (NSCLC). SKIL expression levels in NSCLC cell line, clinical sample, and adjacent normal tissue were measured by quantitative PCR, western blot, or immunohistochemistry. Lentivirus was used to overexpress/silence SKIL or TAZ expression. Malignant phenotypes of NSCLC cells were evaluated by colony formation, transwell, and MTT assays, and in xenograft mice model. Syngeneic mice model and flow cytometry were used to evaluate T cell infiltration. Quantitative PCR and western blot were applied to evaluate relevant mRNA and protein levels, respectively. Co-immunoprecipitation was applied to unveil the interaction between SKIL and TAZ. SKIL expression was higher in NSCLC tissue compared to adjacent normal tissue. Silencing of SKIL inhibited malignant phenotypes of NSCLC cells and promoted T cell infiltration. SKIL-knockdown inhibited autophagy and activated the STING pathway in NSCLC cells through down-regulation of TAZ. Silencing of TAZ cancelled the effects of SKIL overexpression on malignant phenotypes and autophagy of NSCLC cells. Inhibition of autophagy reversed the effects of SKIL/TAZ overexpression on the STING pathway. In conclusion, SKIL promoted tumorigenesis and immune escape of NSCLC cells through upregulation of TAZ/autophagy axis and inhibition on downstream STING pathway.

An Novel Approach in Protective Gene Therapy: Recombinant Adeno-Associated Virus 2-Mediated Transfer of the Human Superoxide-Dismutase Gene.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 5265-5265
Author(s):  
Marlon R. Veldwijk ◽  
Carsten Herskind ◽  
Stephanie Laufs ◽  
Marius Stiefelhagen ◽  
W. Jens Zeller ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Gene Therapy ◽  
Superoxide Dismutase ◽  
Tumor Cells ◽  
Normal Tissue ◽  
Therapeutic Window ◽  
Cervix Carcinoma ◽  
Sod Activity ◽  
Adeno Associated Virus ◽  
Tissue Protection

Abstract Background and purpose: The success rate of any therapeutic approach depends on the therapeutic window, which can be increased by either raising the resistance of the normal tissue such as hematopoietic cells without protecting the tumor cells or by sensitizing the tumor cells but not the normal cells. Two promising candidate genes for normal tissue protection against superoxide-induced damage may be the copper-zinc (CuZnSOD) and manganese superoxide-dismutase genes (MnSOD). Oxidative stress-induced apoptosis plays a role in both radiation- and chemotherapy-induced tissue damage. Relevant cytostatic drugs for which oxidative stress as one mechanism of action has been described are e.g. anthracyclins, platinum analogues, etoposide and ara-C. For gene therapeutic approaches, recombinant adeno-associated virus 2 (rAAV-2)-based vectors offer attractive advantages over other vector systems: low immunogenicity, possibility of in vivo application, ability to infect dividing and non-dividing tissues and a low chance of insertional mutagenesis, due to extra-chromosomal localization. Here, we report the production and testing of novel rAAV-2-SOD vectors with the goal of normal tissue protection. Material and methods: Various rAAV-2 vectors containing CuZnSOD, MnSOD and fusion proteins of both with the enhanced green fluorescent protein (eGFP) gene were cloned and vector stocks were produced. Human cervix carcinoma (HeLa-RC) cells were chosen for their susceptibility to rAAV-2. Cells were seeded and transduced with the rAAV-2-SOD vectors. Gene transfer and transgene expression were investigated using FACS and an SOD-activity assay. Results: Over 70% of all HeLa cells expressed SOD and significant amounts of functional SOD protein were detected (table 1). Conclusion: These results forms the basis to evaluate the radio- and chemoprotective effects of AAV-mediated SOD gene therapy in hematopoietic and non-hematopoietic (e.g. mucosal) cells. Vector % GFP+ cells SOD activity (U/mg) Mock control - 435 ± 37 rAAV-2-CuZnSOD N/A 965 ± 112 rAAV-2-CuZnSOD/eGFP 78 ± 2 1093 ± 178 rAAV-2-MnSOD N/A 1516 ± 191 rAAV-2-MnSOD/eGFP 77 ± 3 1204 ± 124

scholarly journals ATIM-09. CLINICAL TRIAL IN PROGRESS: A STUDY OF NEOADJUVANT AND ADJUVANT VB-111 FOR TREATMENT OF RECURRENT GBM

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi3-vi3
Author(s):  
Timothy Cloughesy ◽  
Nicholas Butowski ◽  
Dror Harats ◽  
Tamar Rachmilewitz Minei ◽  
Patrick Wen
Keyword(s):  
T Cell ◽  
Standard Of Care ◽  
Recurrent Glioblastoma ◽  
T Cell Response ◽  
Antiangiogenic Effect ◽  
T Cell Infiltration ◽  
Surgical Trial ◽  
Pharmacodynamic Markers ◽  
Consecutive Time ◽  
Dual Mechanism

Abstract BACKGOUND Ofranergene obadenovec (VB-111) is a targeted anti-cancer viral based gene therapy with a dual mechanism: a broad antiangiogenic effect and induction of a tumor directed immune response. Previous study demonstrated a survival benefit for patients with recurrent glioblastoma (rGBM) treated with VB-111 monotherapy that was continued upon progression with combination treatment of VB-111 and bevacizumab. Glioblastoma is an immunologically “cold” microenvironment which fosters immunosuppression and antagonizes anti-tumor immune responses. The role of T-cell infiltration in combating cancer has been increasingly recognized and associated with improved participant outcomes. Based on these observations, this study will assess the hypothesis that neoadjuvant use of VB-111 will lead to a statistically significant increase in tumor infiltrating T lymphocyte (TIL) density within the tumor and enhanced systemic tumor-specific T cell responses. METHODS This is a multicenter, randomized, blinded, placebo-controlled, phase 2 surgical trial to evaluate early immunologic pharmacodynamic parameters for the viral cancer therapy VB-111 in rGBM. 45 participants with rGBM indicated for resection will randomized to one of three treatment arms: Neoadjuvant Arm: intravenous VB-111 prior to resection, and VB-111 every 6 weeks after resection. Adjuvant Arm: placebo prior to resection, and VB-111 every 6 weeks afterwards. The control arm will receive placebo prior to resection followed by standard of care. Upon evidence of contrast-enhancing progression, bevacizumab may be initiated as needed for supportive care and VB-111 will continue until progression is supported at two consecutive time points. Tumor samples will be obtained and archived at the time of surgery, and blood samples will be obtained as pharmacodynamic markers throughout the study to allow DNA sequencing of T cells. The primary endpoint is influence of neoadjuvant VB-111 on TIL density. Other endpoints include safety and tolerability, peripheral T cell response, tumor/microenvironment transcriptomic alteration, and PFS/OS. Study will open for enrolment in 2019.

scholarly journals Selective reactivation of STING signaling to target Merkel cell carcinoma

2020 ◽  
Vol 117 (24) ◽  
pp. 13730-13739 ◽  
Author(s):  
Wei Liu ◽  
Gloria B. Kim ◽  
Nathan A. Krump ◽  
Yuqi Zhou ◽  
James L. Riley ◽  
...  
Keyword(s):  
T Cell ◽  
Cell Carcinoma ◽  
Tumor Cells ◽  
Merkel Cell Carcinoma ◽  
Targeted Delivery ◽  
Tumor Antigens ◽  
Innate Immune ◽  
Merkel Cell ◽  
Adaptive Responses ◽  
Chemokine Production

Merkel cell carcinoma (MCC) is a lethal skin cancer that metastasizes rapidly. Few effective treatments are available for patients with metastatic MCC. Poor intratumoral T cell infiltration and activation are major barriers that prevent MCC eradication by the immune system. However, the mechanisms that drive the immunologically restrictive tumor microenvironment remain poorly understood. In this study, we discovered that the innate immune regulator stimulator of IFN genes (STING) is completely silenced in MCCs. To reactivate STING in MCC, we developed an application of a human STING mutant, STINGS162A/G230I/Q266I, which we found to be readily stimulated by a mouse STING agonist, DMXAA. This STING molecule was efficiently delivered to MCC cells via an AAV vector. Introducing STINGS162A/G230I/Q266Iexpression and stimulating its activity by DMXAA in MCC cells reactivates their antitumor inflammatory cytokine/chemokine production. In response to MCC cells with restored STING, cocultured T cells expressing MCPyV-specific T cell receptors (TCRs) show increased cytokine production, migration toward tumor cells, and tumor cell killing. Our study therefore suggests that STING deficiency contributes to the immune suppressive nature of MCCs. More importantly, DMXAA stimulation of STINGS162A/G230I/Q266Icauses robust cell death in MCCs as well as several other STING-silenced cancers. Because tumor antigens and DNA released by dying cancer cells have the potential to amplify innate immune response and activate antitumor adaptive responses, our finding indicates that targeted delivery and activation of STINGS162A/G230I/Q266Iin tumor cells holds great therapeutic promise for the treatment of MCC and many other STING-deficient cancers.

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