bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plinabulin as a novel small molecule clinical stage immuno-oncology agent for NSCLC.
Authors: Mohanlal Ramon W. , LLoyd Ken , Huang Lan , Bazhenova Lyudmila 
Published: November 2019

139 Background: Plinabulin (Plin) is a small molecule with tumor-inhibiting and immune-enhancing effects. In preclinical studies, Plin induces dendritic cell maturation and related IL-1β, IL-6 and IL-12 release, enhances antigen-specific CD4 T-cell proliferation, reduces regulatory T-cells and M2 macrophages in tumor tissue. Plin had synergistic efficacy with checkpoint inhibitors (PD-1 +/- CTLA-4) in animal models of tumor growth. Plin is targeting critical steps in the immune-cascade, independent from that of PD-1/PD-L1 binding. Methods: In a Phase 2 clinical trial, patients (pts) with and without measurable lung lesion were randomized to docetaxel (D) alone at 75 mg/m2 or Plin with D (Plin+D), in 30 mg/m2 or 20 mg/m2 Plin cohorts, given every 3 weeks (NCT00630110). The primary efficacy endpoint was mOS. Secondary endpoints were safety assessments, DOR, PFS, ORR. PD-L1 tumor status was not characterized. Results: In the 30 mg/m2 cohort, n=50 patients received 30 mg/m2 Plin+ D and n=55 patients received D alone; 72% had measurable lung lesion. In pts with a measurable lung tumor, Plin+D (n=38) was numerically more effective vs. D alone (n=38). mOS, PFS and ORR were 11.3 mo, 3.7 mo, and 18% respectively for Plin+ Doc, and 6.7 mo, 2.9 mo, and 10.5% resp for D alone. DOR (a marker of immune effect) with the Plin+D vs. D alone was 12.7 mo vs. 1 mo (p<0.05). Plin+D did not induce immune-related adverse events (IR-AEs), but prevented D- induced neutropenia (p<0.0002), and D-dose-reduction due to toxicity. The 30 mg/m2 Plin cohort was more effective than the 20 mg/m2 cohort as an anticancer agent. Conclusions: Plin added to D increases efficacy vs. D alone most likely through an immune-related mechanism independent from PD1/PD-L1 intervention and mitigates the known D-related safety concerns, without increasing IR-AEs. The Plin+D combination might represent an effective and cost-effective alternative to Nivolumab, in particular in PD-L1 negative NSCLC. A global phase 3 trial with Plin+D vs. D alone is underway in pts with at least one measurable NSCLC lesion. Clinical trial information: NCT00630110.
Pan-cancer opportunities for off-label immunotherapy based on nonsynonymous mutation burden.
Authors: Knepper Todd Cory , Teer Jamie K. , Walko Christine Marie , McLeod Howard L. 
Published: November 2019

14 Background: In an effort to better predict which cancer patients (pts) are more likely to derive clinical benefit from immunotherapy, an association between increased non-synonymous mutation burden and likelihood of clinical response has been described. This study reports the mutation burden of pts with a variety of advanced cancers within a real-world clinical genomics database in order to highlight opportunities where off-label immunotherapy can be considered. Methods: For each solid cancer assayed by FoundationOne within Moffitt’s Clinical Genomic Action Committee (CGAC) database, a non-synonymous mutation burden was determined. Pts were then grouped by cancer type and descriptive statistics used to describe the mutation burden. For cancers with at least 5 cases, the percentage of pts with a non-synonymous mutation burden exceeding a threshold shown to be suggestive of clinical benefit from immunotherapy ( ≥ 13) is reported. The threshold was derived via linear regression from the “intermediate-high” mutation burden classification of the FoundationOne assay. Results: 520 pts received a FoundationOne test. The median non-synonymous mutation burden was 7 and the mean was 11.4. More pts with cancers that have demonstrated response to immunotherapy had a mutation burden exceeding the threshold (19.7% for lung – 45.0% for melanoma). Pt tumors from cancer types without immunotherapy indications sometimes (5.0% for salivary gland – 10.5% for breast and colorectal cancer) exceeded mutation threshold suggestive of benefit. Conclusions: A meaningful proportion of pts with cancer types without FDA-approved immunotherapies have a mutation burden for which immunotherapy may represent a clinical consideration. [Table: see text]
Expansion of tumor infiltrating lymphocytes (TIL) from bladder cancer.
Authors: Poch Michael Adam , Hall MacLean S , Kodumudi Krithika Nandakumar , Croft Cortlin , Fishman Mayer N. , Mullinax John , Mule' James J , Sarnaik Amod , Pilon-Thomas Shari 
Published: November 2019

142 Background: Patients with advanced bladder cancer have limited therapeutic options resulting in a median overall survival (OS) between 12 and 15 months. At our institution, adoptive cell therapy (ACT) using tumor infiltrating lymphocytes (TIL) has resulted in a durable median OS of 52 months in patients with metastatic melanoma. Immune-mediated anti-tumor responses have been previously shown in bladder cancer, therefore we investigated the phenotype and function of TIL expanded from bladder tumors to establish feasibility of ACT for the treatment of bladder cancer. Methods: Tumor specimens, including primary bladder tumors and lymph node metastases, were collected from 29 bladder cancer patients having standard of care tumor resection, who also had consented to an IRB-approved protocol for TIL generation. The tissue was minced into fragments, placed in individual wells of a 24-well plate, and propagated in high dose IL-2 for four weeks. TIL were considered expanded if they propagated to fill ≥2 wells. The remaining tumor material was digested into a single cell suspension and frozen. TIL were phenotyped by flow cytometry and assessed for autologous tumor reactivity through co-culture with tumor digest and IFN-gamma ELISA. Results: Transitional cell bladder tumors were cultured from 23 patients, of whom 19 (83%) demonstrated TIL expansion. Microbial contamination precluded TIL growth in six specimens. TIL were cultured from 9/12 (75%) patients with preceding chemotherapy and 10/11 (91%) who were chemotherapy naive. Expanded TIL were predominantly CD3+(median 63%, range 10-87%) with a median of 30% CD8+ T cells (range 5-70%). Eight of 15 tested samples (53%) contained TIL that secreted IFN-gamma in response to autologous tumor. Conclusions: The study establishes the practical first step towards an autologous TIL therapy process for therapeutic testing in patients with bladder cancer. Human bladder cancer tissue can be used to expand tumor-specific TIL in vitro. TIL were also expanded from patients that received chemotherapy prior to tumor resection. Future efforts will explore the ability to further expand bladder TIL cultures to clinically meaningful numbers to develop novel ACT strategies for patients with this diagnosis.
CD70 as a novel target of CAR-T-cell therapy for gliomas.
Authors: Jin Linchun , Ge Haitao , Yang Changlin , Long Yu , Chang Yifan(Emily) , Mu Luyan , Sayour Elias , De leon Gabriel , Wang Qiong J. , Yang James C. , Drake Jeffrey , Kubilis Paul , Lu Dunyue , Kong Yingjun , Hu Li , Jiping Qi , Gu Yunhe , Lin Zhiguo , Mitchell Duane Anthony , Huang Jianping 
Published: November 2019

148 Background: Gliomas are the most common primary malignant brain tumor and are uniformly lethal. Cancer immunotherapy has the potential to target gliomas; however, its antitumor effects are restricted by limitations in clinically useful tumor specific targets. Chimeric antigen receptor modified T-cell (CAR-T) therapy is a highly promising option for cancer treatment, due to its combination of precision antibody recognition and T-cell tumor-specific killing. CD70 is an antigen expressed by limited subsets of normal lymphocytes and dendritic cells but is aberrantly overexpressed by glioma cells, which makes it an outstanding glioma-antigen target. Methods: The gene and protein expression of CD70 were evaluated to identify its potential as a glioma target. Human and mouse versions of CD70-specific CAR-T cells were generated, and human primary GBM lines as well as murine lines (GL-261, KR-158B) were used as human and mouse tumor targets, respectively. The antitumor effect of the human and mouse CD70-sepecific CARs were tested in vitro and in orthotopic xenograft and syngeneic murine models. Results: CD70 is only overexpressed by tumor cells in a subset of low-grade gliomas and GBM. The elevated gene and protein expression are associated with increased tumor grade and poor patient survival. Co-culturing CD70-specific CAR-T cells with CD70-positive glioma cells resulted in potent secretion of IFN-gamma and tumor-specific killing in a CD70-dependent manner. Irradiation enhances CD70 expression on glioma cells and thus increases CAR T-cell recognition. Adoptive transfer of the human and mouse CD70 CAR-T cells resulted in tumor regression of immunocompetent and immunodeficient mice, respectively. Conclusions: CD70 can be an excellent tumor target for gliomas, and CD70-specific CAR-T cells have potent antitumor activity against CD70-positive gliomas both in vitro and in vivo. Our study provides crucial preclinical evidence to support the future clinical application of CD70 CAR-T cells to treat gliomas.
Development of a novel T-cell immunotherapy targeting HEATR1.
Authors: Dossa Robson Grando , Cunningham Tanya , Bleakley Marie 
Published: November 2019

149 Background: Allogeneic hematopoietic stem cell transplantation (HCT) often cures acute leukemia. However leukemic relapse remains a major cause of HCT failure, and patients with post-HCT relapse have a very poor prognosis. We are developing T cell immunotherapies targeting leukemia-associated minor histocompatibility (H) antigens to manage post-HCT relapse. Because the presentation of minor H antigens is HLA-restricted, a panel of hematopoietic-restricted, leukemia-associated minor H antigens is required to enable the development of broadly applicable minor H antigen targeted immunotherapy. We previously discovered a HLA- B*0801-restricted, leukemia-associated minor H antigen, HEATR1. We showed that HEATR1-specific T cells can specifically kill leukemic blasts and prevent engraftment in a murine model, implying that this minor H antigen is expressed in leukemic stem cells. We have now developed immunotherapy targeting HEATR1 using genetically modified T cells. Methods: We isolated a HEATR1-specific T cell clone from the peripheral blood of a normal donor and sequenced its T cell receptor (TCR). The TCR was codon-optimized and cysteine-modified to maximize expression in T cells and reduce the risk of mispairing with endogenous TCR chains, then cloned into a multicistronic lentiviral vector (LV). Primary CD8+T cells were transduced with the HEATR1 TCR LV and evaluated with a range of assays. Results: The HEATR1-specific T cell clone specifically killed B8+ HEATR1+ primary leukemia. Similarly, CD8+ HEATR1 TCR-transduced T cells killed target cells pulsed with HEATR1 peptide (ISKERAEAL), but not the allelic variant control peptide (ISKERAGAL), and specifically killed cell lines that endogenously present the HEATR1 minor H antigen. HEATR1-transduced T cells also secrete cytokines and proliferate in response to HEATR1+ but not HEATR1-cells. Conclusions: We have demonstrated that HEATR1-specific T cell clone and HEATR1 TCR-transduced T cells can kill HEATR1+ cells. If the safety and efficacy of HEATR1 TCR immunotherapy is confirmed in further preclinical studies, development of phase I clinical studies will be warranted and may ultimately provide a new option for management of relapse after HCT.
Development of human NKG2D-CD3ε chimeric antigen receptor (CAR) for T-cell-mediated cancer immunotherapy.
Authors: Kusmartsev Sergei , Vieweg Johaness , Prima Victor 
Published: November 2019

150 Background: NKG2D is a lectin-like type 2 transmembrane receptor that expressed by natural killer cells and some T cell subsets. Stimulation of NKG2D receptor with specific agonistic ligands produces activating signals through signaling adaptor protein DAP10 leading to the enhanced cytokine production, proliferation, and cytotoxicity against tumor cells. There is strong evidence that NKG2D ligands are expressed in many human tumors, including melanoma, leukemia, myeloma, glioma, and carcinomas of the prostate, breast, lung, and colon. Recent studies also demonstrated that T cells bearing chimeric antigen receptor (CAR) NKG2D linked to CD3ζ (zeta) chain produce marked in vitro and in vivo anti-tumor effects. The aim of current study was to determine whether human T cells bearing chimeric antigen receptor (CAR) NKGD2 linked to CD3ε (epsilon) chain could be activated by the NKG2D-specific stimulation and able to kill human cancer cells. Given the important role of CD3ε in activation and survival of T cells, we hypothesized that NKG2D-CDε-bearing T cells could exert strong in vitro and in vivo anti-tumor effects. Methods: NKG2D CAR was produced by linking human NKG2D to DAP10 and the cytoplasmic portion of the CD3ε chain. Original full-length human cDNA clones were obtained from NIH Mammalian Gene Collection (MGC). Functional domain analysis and oligonucleotide design in the in-Fusion system of DNA cloning (Clontech) was used to generate the retroviral expression constructs. Results: Human PBMC-derived T cells were retrovirally transduced with newly generated NKG2D-CD3ε CAR DNA construct. These NKG2D CAR-expressing human T cells responded to NKG2D-specific activation by producing IFN-γ and exhibited significant cellular cytotoxicity against human tumor cells in vitro. In vivo studies demonstrated that NKG2D-CD3ε-bearing cells are capable of inhibiting growth of DU-145 human prostate cancer in the immunodeficient mice. Conclusions: Collectively, our data indicate the feasibility of developing chimeric antigen receptor NKG2D-CD3ε for T cells and suggest that adoptive transfer of T cells bearing NKG2D-CD3ε CAR could be potentially effective for immunotherapy of cancer patients.
Combinatorial IL13Rα2 chimeric antigen receptor-T cells plus checkpoint blockade to treat solid tumors in murine and canine models.
Authors: Yin Yibo , Boesteanu Alina , Xu Chong , Posey Avery , Cook Danielle , Blouch Kristin , McGettigan-Croce Bevin , Mason Nicola , June Carl H. , Lin Zhiguo , Johnson Laura A. 
Published: November 2019

152 Background: Glioblastoma (GBM) is a deadly cancer, with a 5-year survival rate of less than 10%. T cells can be redirected to kill cancer cells using chimeric antigen receptors (CAR), a promising method to treat solid tumors. IL13Rα2 is expressed in many solid tumors but not normal tissues, and provides a target for CAR T cells as a powerful immunotherapy treatment. Methods: Human and canine tumors were screened for IL13Rα2 expression by flow cytometry and RT-PCR. Different IL13Rα2 single-chain variable fragments (scFv) were tested in CARs in vitro against human and canine recombinant IL13Rα2 protein to identify a cross-reactive clone. IL13Rα2 CARs expressed in human and canine T cells and showed antigen-specific stimulation by cytokine secretion and target cell lysis. Solid tumors were used to establish in vivo subcutaneous and orthotopic xenograft models in NSG mice. Mice received a single treatment of 2-5 million CAR T cells IV with or without anti PD-1, CTLA-4 or TIM3 mAb checkpoint blockade. Results: IL13Rα2 was detected on three human GBM (D270, U251 and U87), four canine osteosarcomas (BW-, CS-, MC- and SK-KOSA) and two canine lung cancer cell lines (Cacal3, Cacal5). Two different IL13Rα2 CAR were generated that recognized human IL13Rα2 and not IL13Rα1, one also recognized canine IL13Rα2. Five million IL13Rα2 CAR T-cells delivered IV were able to eliminate established GBM tumors. Use of fewer CAR T cells initially controlled tumor growth, followed by tumor outgrowth correlated with expression of T cell exhaustion markers. Combined treatment with CARs plus checkpoint blockade mAb delivered IP had synergistic effects, restoring anergic T-cell function and improving tumor treatment. Conclusions: IL13Rα2 is highly expressed on human and canine tumors, but not normal tissues. IL13Rα2 specific CAR T cells successfully respond to human and canine tumors and treat GBM in a xenograft mouse model, although this effect was transient at lower treatment doses. Addition of checkpoint blockade mAbs to CAR therapy was beneficial for the treatment of solid tumors. We plan to utilize this treatment in a canine spontaneous cancer preclinical model and translate into clinical trials for patients with GBM.
MVA-5T4 immunotherapy and low-dose cyclophosphamide for advanced colorectal cancer (TaCTiCC): An open-label, randomized phase I/II trial.
Authors: Scurr Martin , Pembroke Tom , Adams Richard , Blount Daniel , Brewster Alison , Gwynne Sarah , Harrop Richard , Jones Robert , Hills Robert , Gallimore Awen , Godkin Andrew 
Published: November 2019

154 Background: Current immunotherapies including checkpoint inhibitors and vaccines for advanced colorectal cancer (CRC) have been largely ineffective. We hypothesized that combining an MVA-based vaccine targeting the tumor-associated antigen 5T4 (TroVax) with low-dose cyclophosphamide to deplete Foxp3+regulatory T-cells (Tregs), could improve immunological responses and patient outcomes. Methods: In this open-label phase I/II clinical trial, TaCTiCC (TroVax and Cyclophosphamide Treatment in Colorectal Cancer) 53 patients with inoperable metastatic CRC were randomized to receive either no treatment (group 1, n=8), metronomic low-dose CPM (50mg B.D. during treatment weeks 1&3; group 2, n=9), TroVax only (6 i.m. injections weeks 4 to 16, group 3, n=18), or low-dose CPM followed by TroVax (group 4, n=18). The primary endpoint was boosted anti-5T4 responses at week 7, as measured by increased T-cell and antibody responses; secondary endpoints included progression-free (PFS)/overall survival (OS), and anti-5T4 responses over the trial period. Results: CPM depleted Tregs in 21/27 patients during treatment week 3 (p=0.0045), resulting in significantly prolonged PFS amongst groups 2&4 over group 1 (5.0 vs. 2.5 months, HR=0.17 95% CI 0.048-0.62, p=0.0072). TroVax induced a >2-fold increase in anti-5T4 immune responses in 15/36 group 3&4 patients; these patients experienced significantly prolonged median PFS (6.5 vs. 2.4 months, HR 0.31 95% CI 0.14-0.65, p=0.0022) and OS (20 vs. 12 months, HR=0.37 95% CI 0.17-0.82, p=0.014). Combination of CPM & TroVax was not significantly superior. The primary endpoint at a single timepoint was not met since CPM-induced responses declined by week 7, and TroVax-induced responses were greatest at weeks 10-16. No serious adverse events were reported. Conclusions: Both CPM and TroVax induced highly beneficial anti-tumor immune responses resulting in significantly prolonged survival of end-stage CRC patients without toxicity. This is the first study to show a clear benefit of immunotherapy in advanced CRC, and suggests this approach may be superior (and less toxic) to continuous palliative chemotherapy in these patients. Clinical trial information: 54669986.
A novel cancer vaccine platform utilizing autologous tumor lysate loaded into capped yeast cell wall particles.
Authors: Peace Kaitlin M. , Vreeland Timothy J , Hale Diane F , Jackson Doreen O , Greene Julia M , Trappey Alfred F , Berry John S , Clifton Guy T , Herbert Garth S , Yu George , Wagner Tom , Peoples George Earl 
Published: November 2019

169 Background: Our current tumor lysate, particle-loaded, dendritic cell (TLPLDC) vaccine employs yeast cell wall particles (YCWP) to deliver antigen to DC ex vivo and is being tested in a randomized phase IIb trial. This strategy may be improved by injecting TL-loaded YCWP as an intradermal vaccine, with in vivo DC uptake. Silicate capping should allow YCWP to retain TL longer and stimulate DC uptake. Here, we present preclinical data on the tumor lysate, particle only (TLPO) vaccine concept vs. TLPLDC. Methods: To test the TLPO concept, YCWP were loaded with fluorescence (flr) labeled albumin and capped (cp) vs. uncapped (ucp) particles were compared for flr leak. Next, YCWP were added to cultured macrophages to evaluate DC uptake. Cells were then lysed, centrifuged, and flr in the cytoplasm vs. organelles measured. 3 C57B mice were then injected with 100ml NaCl, 106empty cp YCWP, or 1mcg GM-CSF. 5 hours (hr) post-injection, 100ml NaCl was injected into the same site, withdrawn, and examined via microscope to count monocytes. TLPO was compared to TLPLDC in a B16 murine melanoma survival model. Finally, 4 grey horses with equine melanoma were treated with autologous TLPO, injected biweekly for 4 vaccinations. Target lesions were assessed over 6 months. Results: Compared to ucp YCWP, cp had decreased flr leak at 1 (15.8% vs. 24.7%) and 2 hr (6.7% vs. 16.6%), increased uptake by DC (2hr flr readings 11065 vs. 3928) and higher delivery to DC cytoplasm (68.9% vs. 48.8%). Empty cp YCWP showed increased recruitment of monocytes (276/hpf) vs. GM-CSF (55/hpf) or NaCl alone (18/hpf). In the B16 murine melanoma model, the median survival time in days was 21 for controls (n=5), 42 for TLPLDC (n=10), and 56 for TLPO (n=20). At 6 months, the equine model revealed 1 complete and 3 partial responses (50%, 68%, and 45% tumor reduction). Conclusions: Silicate capping of the YCWP effectively limits leakage of contents, improves uptake by DC and delivery to the cytoplasm without the need for GM-CSF. In early animal studies, TLPO appears to have equivalent efficacy to TLPLDC, but eliminates the need for in vitro DC loading. We plan to perform a bridging study comparing TLPO to TLPLDC after enrollment is complete in our phase IIb TLPLDC melanoma trial.
Identification of somatic mutations and neoantigens to predict development of autoimmune adverse events to immune therapy in melanoma.
Authors: Wells Keith Ryan , Amato Carol M , Hintzsche Jennifer , Robinson William 
Published: November 2019

19 Background: Immunotherapy has quickly altered the treatment paradigm for advanced melanoma. Prior studies using whole exome sequencing (WES) in immunotherapy have shown limited correlation with clinical response to immunotherapy, but not an evaluation of autoimmune side effects. Understanding mechanisms of immune-related adverse events (irAE) at a genomic level may lead to improved rational treatment design and better patient selection. Methods: DNA was extracted from 87 tumor samples from 49 patients with metastatic melanoma treated with ipilimumab (anti-CTLA-4) or with nivolumab or pembrolizumab (anti-PD-1) immunotherapy. WES was performed with exome capture on an Illumina HiSeq sequencer. Statistical analysis was performed with Chi-squared testing. Computational neoantigen analysis has been performed on the sequencing data. Results: 27 patients with advanced or metastatic melanoma were treated with only ipilimumab, 11 with only anti-PD1, and 11 patients were treated with both anti-CLTA-4 and anti-PD1 either sequentially or in combination. irAE evaluated included cutaneous, colitis, endocrinopathies, hepatitis, and pneumonitis. In 10 patients who developed colitis, 14 mutated genes were enriched in their tumor samples (p=0.01-0.046) compared with patients without colitis. Analyzing all patients with any irAE versus no irAE treated with anti-CTLA-4, anti-PD1, or both (either sequential or combination) revealed 7 mutated genes enriched in patient samples who developed irAE (p=0.02-0.05). Preliminary neoantigen analysis has identified possible irAE associated neoantigens and further analysis of additional samples are ongoing. Overall mutational burden of the tumor samples did not correlate with development of irAE. Conclusions: Autoimmune side effects are frequent and often serious side effects of immunotherapy for melanoma. Genetic analysis may provide insight in prediction of these side effects and help direct therapeutic decisions.