bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 4025: STEAP4 ISH and IHC diagnostics for Tarloxotinib activation in EGFR/HER2 mutant cancers
Authors: Yu Hui , Silva Shevan , Estrada-Bernal Adriana , Rivard Chris , Hirsch Fred , Abbatista Maria , Smaill Jeff , Doebele Robert C. , Patterson Adam , Vellanki Avanish , Tirunagaru Vijaya G. 
Published: August 2019

Abstract
Background: Tarloxotinib is a clinical-stage prodrug that releases a potent, irreversible EGFR/HER2 inhibitor (Tarloxotinib-E) selectively in severely hypoxic regions of tumors. One-electron reduction leads to loss of the trigger moiety under oxygen-deficient conditions, releasing the neutral, diffusible ‘warhead’ Tarloxotinib-E. CRISPR/cas9-mediated disruption of the metalloreductase STEAP4 has demonstrated its role as the dominant plasma membrane reductase that facilitates one-electron reduction of Tarloxotinib.
Methods: Cancer cell lines, PDX and resected tumor tissues processed in Formalin Fixed Paraffin Embedded (FFPE) blocks were evaluated. RNAScope technology was used to develop a method to assess STEAP4 mRNA expression by in situ hybridization using specific probes for human STEAP4. mRNA ISH technology for STEAP4 was optimized on a Leica Bond RX autostainer for detection of STEAP4 in FFPE specimens. STEAP4 antibodies were evaluated for Immunohistochemistry (IHC) analysis. STEAP4 IHC was employed as cross-reference, using an anti-STEAP4 antibody validated against STEAP4 knockout and over-expressing cell line and tumor models. Staining data was compared to quantitative PCR results for mRNA ISH and Western blot analysis for IHC. STEAP4 mRNA expression was assessed in FFPE sections of various EGFR/HER2 mutant tumor xenografts and EGFR/HER2 mutant patient tumor specimens.
Results: The STEAP4 mRNA ISH assay was optimized and validated using FFPE sections from cell lines and STEAP4 overexpressing tumor blocks and compared to wild type tumors with minimal expression. High level of STEAP4 mRNA was observed in STEAP4 overexpressing tumors. STEAP4 mRNA ISH analysis revealed variable levels of expression in EGFR/HER2 mutant xenograft tumors. STEAP4 mRNA and protein expression level correlated with Tarloxotinib conversion to Tarloxotinib-E. STEAP4 mRNA expression in EGFR/HER2 mutant patient tumor specimens will be presented.
Conclusion: STEAP4 reduces Tarloxotinib and leads to the conversion to the active drug, Tarloxotinib-E, in hypoxic tumors. Assessment of STEAP4 expression in individual patients is important to guide patient stratification in Tarloxotinib clinical trials and represents an attractive biomarker to enroll tarloxotinib-responsive patients in clinical trials.
Citation Format: Hui Yu, Shevan Silva, Adriana Estrada-Bernal, Chris Rivard, Fred Hirsch, Maria Abbatista, Jeff Smaill, Robert C. Doebele, Adam Patterson, Avanish Vellanki, Vijaya G. Tirunagaru. STEAP4 ISH and IHC diagnostics for Tarloxotinib activation in EGFR/HER2 mutant cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4025.
Abstract 4036: The efficacy of immune checkpoint inhibitors in patients with EGFR mutated non small cell lung cancer in retrospective analysis
Authors: Yamada Tadaaki , Hirai Soichi , Yoshimura Akihiro , Watanabe Satoshi , Uchino Junji , Takayama Koichi 
Published: August 2019

Abstract
Background The treatment with EGFR-TKIs leads to initial response in most patients with EGFR mutated non-small cell lung cancer (NSCLC). In contrast, little is known the subpopulation of NSCLC patients with EGFR mutations who had clinical outcomes to treat for immune checkpoint inhibitors (ICIs). Therefore, to seek for the eligible cases to treat with ICIs, we retrospectively analyzed the correlation between clinical feature and the efficacy of ICIs in patients with EGFR mutations.
Methods/Materials and methods We analyzed a retrospective study of patients with advanced NSCLC harboring with EGFR mutations who were treated with ICIs after the resistance to EGFR-TKIs between February 2016 and April 2018 at six institutions in Japan. The association between clinical outcome and the efficacy or ICIs was investigated.
Results We enrolled 27 patients who have EGFR activating mutation. The objective response and disease control rates were higher in patients with uncommon EGFR mutations than in those with common EGFR mutations (71% versus 35.7%, and 57% versus 7%, p= 0.14 and p &lt; 0.01, respectively). Patients with uncommon EGFR mutations or without T790M mutations was associated with a significantly longer median progression-free survival than those with common EGFR mutations or with T790M mutations (p = 0.003, 0.03, respectively).
Conclusions Patients with uncommon EGFR mutations and without T790M mutations are associated with best outcomes for the treatment with immunotherapy among EGFR mutated NSCLC in the retrospective analysis. Further research is needed to validate for the clinical biomarkers involved in ICI responders with EGFR mutation.
Citation Format: Tadaaki Yamada, Soichi Hirai, Akihiro Yoshimura, Satoshi Watanabe, Junji Uchino, Koichi Takayama. The efficacy of immune checkpoint inhibitors in patients with EGFR mutated non small cell lung cancer in retrospective analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4036.
Abstract 4049: Cellular phenotypes of spleen cells in cancer patients targeted for adoptive cellular therapy
Authors: Cole Kathryn , Ly Quan , Cox Jesse L. , Hollingsworth Michael A. , Padussis James C. , Foster Jason M. , Vargas Luciano M. , Talmadge James E. 
Published: August 2019

Abstract
The spleen is a rich resource of large numbers of lymphocytes, with potential for use in adoptive cellular therapy (ACT). This is of particular relevance to patients with a distal pancreatic ductal adenocarcinoma (PDAC) who frequently undergo a pancreatectomy that required a splenectomy to clear the nodal basin. In this study we compared the phenotypes of eight paired sets of peripheral blood (PB) and spleen cell populations to assess the frequency of myeloid derived suppressor cells (MDSC) and lymphocyte subpopulations. Because a positive clinical response to ACT requires a low frequency of T-regs and MDSC’s, both systemically and in the tumor microenvironment these cells were one of the foci for our studies. A high frequency of these cells negatively correlate with survival and positively with tumor burden. Indeed, in this study we observed a significant decrease in the frequency of granulocytic, monocytic and immature MDSC’s in the spleen vs PB (4.8±1.6 vs. 54.4±6.1; 0.2±0.1 vs. 0.9±0.4; and 0.6±0.1 vs. 2.3±0.8 percent respectively) but not T-regulatory (T-reg) cells (0.8+0.5 vs. 0.1+0.04 percent) supporting the potential superiority of spleen cells relative to PB as a cellular source for ACT. In addition to a significantly higher number of spleen cells as compared to the PB for expansion/infusion, spleens have a higher frequency of T-cells as compared to the PB including CD3+ (35+5 vs. 16+4%), CD4+ (19+2 vs. 10+2%) and CD8+ (10+1 vs. 5+2%) T-cells. The frequency of transitional memory (Ttm) T-cells, which have a high proliferative potential were also significantly increased in the spleen vs. PB (37.5±6 vs. 26±3.0%) as was the frequency of PD1+CD8+ T-cells (8+2 vs 1+0.5%), which have been shown to have tumor specific cytotoxicity in cancer patients. In summary the increased frequency of PD-1+CD8+ cells, a Ttm memory phenotype and low levels of an exhaustion phenotype (TIM3 and Lag3 expression) in spleen cells vs the PB is supportive of the potential utility of these cells for expansion and therapeutic utility for these cells.
Citation Format: Kathryn Cole, Quan Ly, Jesse L. Cox, Michael A. Hollingsworth, James C. Padussis, Jason M. Foster, Luciano M. Vargas, James E. Talmadge. Cellular phenotypes of spleen cells in cancer patients targeted for adoptive cellular therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4049.
Abstract 4072: A combinational therapy of oncolytic virus and nature killer cells for melanoma treatment
Authors: Chen Lin , Chen Xianju , Tan Xiankui , Li Meng , Hu Fang , Zhang Haiyan , Wang Xiaoyuan 
Published: August 2019

Abstract
Immunotherapy has obtained substantial impact on the clinical treatment of melanoma which is largely resistant to current therapies as chemotherapy and radiotherapy. Oncolytic virotherapy of melanoma is an appealing approach for inducing not only tumor cell death but also antitumor immunity. Furthermore, NK cells, a lineage of innate lymphocytes, not relying on peptides presented in an HLA class I context, have gained more and more attention as anti-melanoma effector cells. However, the combination of oncolytic adenovirus and NK cells has not yet been explored in melanoma. In this study, the combinational efficacies of oncolytic virus H101 and NK cells was tested in vitro. The combination of H101 and NK cells resulted more efficient killing of tumor cells (HT29, A549 and HepG2) compared to the monotherapies, and displayed no significant cytolytic effect of normal cells (HUVEC and MRC-5). In addition, we present a patient with right maxillary sinus malignant melanoma who was treated with the combination of H101 and adoptive NK cells. We observed intratumoral injections of H101 without dose-limiting toxicity. H101 injections stimulated self-immunity response with transient whole body fever. Furthermore, NK injections caused tumor temperature rise although contralateral cheek temperature was normal and body temperature was normal. Data are consistent with the hypothesis that virus-infected cancer cells attracted NK accumulation within tumor. The homing NK cells attacked targeted cancer cells, causing local temperature rise. Two courses of combination therapy in conjunction mediated the significant durable regression of melanoma, which had been ongoing for &gt;22 months, and it represents a new immunotherapy approach for the treatment of these patients.
Citation Format: Lin Chen, Xianju Chen, Xiankui Tan, Meng Li, Fang Hu, Haiyan Zhang, Xiaoyuan Wang. A combinational therapy of oncolytic virus and nature killer cells for melanoma treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4072.
Abstract 4085: DDR2 inhibition enhances response to anti-PD-1 immunotherapy
Authors: Tu Megan M. , Lee Francis Y. , Jones Robert T. , Kimball Abigail K. , Saravia Elizabeth , Graziano Robert F. , Coleman Brianne , Menard Krista , Yan Jun , Michaud Erin , Chang Han , Abdel-Hafiz Hany A. , Rozhok Andrii I. , Duex Jason E. , Agarwal Neeraj , Chauca-Diaz Ana , Johnson Linda K. , Ng Terry L. , Cambier John C. , Clambey Eric T. , Costello James C. , Korman Alan J. , Theodorescu Dan 
Published: August 2019

Abstract
Therapies targeting PD-1 are used in multiple cancer types. While a fraction of patients show durable therapeutic responses, most remain unresponsive, highlighting an urgent need to better understand and improve these therapies. Using an in vivo screening approach with a customized shRNA pooled library, we identified DDR2 as a leading target for the enhancement of response to anti-PD-1 immunotherapy. Using isogenic in vivo murine models across five different tumor histologies, bladder, breast, colon, sarcoma and melanoma, we show that DDR2 depletion increases sensitivity to anti-PD-1 treatment compared to monotherapy. Combination treatment of tumor-bearing mice with anti-PD-1 and dasatinib, a tyrosine kinase inhibitor of DDR2, also led to tumor load reduction and in some cases, complete clearance. RNAseq and CyTOF analysis revealed higher CD8+ T cell populations in tumors with DDR2 depletion and those treated with dasatinib when either was combined with anti-PD-1 treatment. Our work provides strong scientific rationale for targeting DDR2 in combination with PD-1 inhibitors.
Citation Format: Megan M. Tu, Francis Y. Lee, Robert T. Jones, Abigail K. Kimball, Elizabeth Saravia, Robert F. Graziano, Brianne Coleman, Krista Menard, Jun Yan, Erin Michaud, Han Chang, Hany A. Abdel-Hafiz, Andrii I. Rozhok, Jason E. Duex, Neeraj Agarwal, Ana Chauca-Diaz, Linda K. Johnson, Terry L. Ng, John C. Cambier, Eric T. Clambey, James C. Costello, Alan J. Korman, Dan Theodorescu. DDR2 inhibition enhances response to anti-PD-1 immunotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4085.
Abstract 4093: Synergy of CTL tumor cytotoxicity with myxoma oncolytic virotherapy
Authors: Chen Meixuan , Matos Ana L. , Yuvaraj Padhmavathy , Belmont Laura , McFadden Grant , Anderson Karen S. 
Published: August 2019

Abstract
Background: Checkpoint blockade (CKB) are in clinical trials in breast cancer, but responses may be limited by the low tumor micro-immune profile and somatic mutation burden. Oncolytic viruses may function by activating the immune microenvironment, and improve clinical responses when combined with CKB against cancers like melanoma. In this study, we evaluate the synergy of cytotoxic T lymphocytes (CTLs) combined with oncolytic myxoma virus in an in vitro model of human breast cancer.
Method: BMLF1-CTLs were generated from human HLA-A*02 PBMCs, which were stimulated with antigen presenting cells pulsed with the EBV BMLF1 HLA-A*02 peptide (GLCTLVAML). MCF-7 was engineered to express the full-length BMLF1 gene from EBV. To assess the impact of myxoma virus infection on CTL cytotoxicity, target MCF-7 cells (+/- BMLF1) were co-cultured with BMLF1-CTLs (E:T ratio=5:1) and myxoma virus vMyx-M135KO-GFP (vMyx135KO), at multiplicity of infection (MOI) ranges from 0.1 to 10 ffu/cell, in vitro for 48 hours. Cytotoxicity was measured by flow cytometry with propidium iodide (PI). Cell surface expression of MHC class I and class II were measured by flow cytometry. Statistical comparisons were performed using an unpaired t-test and variation among and between groups was calculated using ANOVA. Statistical significance was defined as p&lt;0.05.
Results: At the highest MOI (10 ffu/cell), cell surface MHC class I expression on MDA-MB-231 was decreased 38-fold (p&lt;0.01), compared to untreated control. MCF-7 was more sensitive to MHC class I downregulation (MOI 1 ffu/cell, 37.3-fold reduction, p&lt;0.002). No significant change of cell surface expression of MHC class II was detected in either breast cancer cell lines at any MOI. In MCF-7-BMLF1- cells, baseline cytotoxicity remained low in both CTL and vMyx135KO (MOI=0.1 ffu/cell) only treatments (14% vs. 10%). With antigen expression (MCF-7-BMLF1+), CTL cytotoxicity increase to 21% (p=0.02). At a MOI of 0.1 ffu/cell, vMyx135KO viral infection further sensitized cells to CTL cytotoxicity (21% vs. 36%, p&lt;0.001)
Conclusions: Oncolytic myxoma virus infection can decrease the MHC class I expression in human breast cancer cell lines, but only at high multiplicities of infection. At low level of virus, myxoma virus infection can enhance CTL cytotoxcity of breast cancer cell line.
Citation Format: Meixuan Chen, Ana L. Matos, Padhmavathy Yuvaraj, Laura Belmont, Grant McFadden, Karen S. Anderson. Synergy of CTL tumor cytotoxicity with myxoma oncolytic virotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4093.
Abstract 4104: Expression of the immune checkpoint receptor TIGIT in seminoma
Authors: Lennartz Maximillian , Blessin Niclas C. , Hinsch Andrea , Simon Ronald , Kluth Martina , Fischer Kristine , Hube-Magg Claudia , Li Wenchao , Mandelkow Tim , Debatin Nicolaus F. , Höflmayer Doris , Sauter Guido , Izbicki Jakob R. , Minner Sarah , Büscheck Franziska , Uhlig Ria , Dum David , Krech Till , Luebke Andreas M. , Wittmer Corinna , Jacbosen Frank , Burandt Eike , Steurer Stefan , Wilczak Waldemar 
Published: August 2019

Abstract
A characteristic feature of testicular seminoma is the abundance of immune cells in the tumor microenvironment, raising the possibility that immune checkpoint inhibitors could be a therapeutic option in these tumors. TIGIT (T cell immunoreceptor with Ig and ITIM domains) is an inhibitory immune checkpoint receptor in analogy to PD-1 and drugs targeting TIGIT are currently tested in clinical trials. Little is known about the expression of these proteins in testicular seminomas. Here, we employed immunohistochemistry to determine the relative abundance of TIGIT and PD-1 in relation to the total CD3+immune cell infiltration in a tissue microarray (TMA) constructed from 78 seminoma patients. The fraction of TIGIT+and PD-1+lymphocytes was highly variable in individual cancers and ranged from 2.3% to 69.4% (mean:32.2±14.7%) for TIGIT and from 0.8% to 56.5% (mean:21.6±13.2%) for PD-1. The same high degree of variability was also found for the ratio of PD-1 to TIGITpositive cells that varied from a dominance of TIGIT (PD-1:TIGIT ratio=0.02) in 74% of patients to a predominance of PD-1 (PD-1:TIGIT ratio=12.5) in 23% of patients. In summary, the immune checkpoint receptors TIGIT and PD-1 are abundantly expressed in human seminomas. Once available, anti-TIGIT antibodies, possibly in combination with anti-PD-1 drugs, may be a promising therapeutic option for clinical studies in this cancer type.
Citation Format: Maximillian Lennartz, Niclas C. Blessin, Andrea Hinsch, Ronald Simon, Martina Kluth, Kristine Fischer, Claudia Hube-Magg, Wenchao Li, Tim Mandelkow, Nicolaus F. Debatin, Doris Höflmayer, Guido Sauter, Jakob R. Izbicki, Sarah Minner, Franziska Büscheck, Ria Uhlig, David Dum, Till Krech, Andreas M. Luebke, Corinna Wittmer, Frank Jacbosen, Eike Burandt, Stefan Steurer, Waldemar Wilczak. Expression of the immune checkpoint receptor TIGIT in seminoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4104.
Abstract 4108: Preclinical evaluation of half-life extended Affimer® biotherapeutics targeting the PD-L1 pathway
Authors: Basran Amrik , Jenkins Emma , Adam Estelle , Laurent Floriane , Writer Michele , Oumie Assa , Sivula Jyrki , West Maureen , Stanley Emma , Hillman Jennifer , Robles-munoz Viviana 
Published: August 2019

Abstract
Programmed Cell Death-Ligand 1 (PD-L1) binds to its receptor, Programmed Cell Death protein (PD-1) and is expressed on a range of activated immune cells and is upregulated by tumor cells and by immune cells in the tumor microenvironment. PD-L1 immunotherapies have emerged as effective treatments both as monotherapies and in combinations, providing long term responses in a subset of patients.
Phage display selections have identified a range of potent Affimer biotherapeutic antagonists to both human and mouse programmed death-ligand 1 (PD-L1). We have demonstrated when formatted as bivalent molecules they have improved sub nM affinity, half-life extension in a mouse PK study, blocking activity in vitro and in vivoefficacy in syngeneic or xenograph mouse models.
Affimer biotherapeutics are a 14kDa monomeric scaffold protein based on the human protease inhibitor Stefin A, lacking post-translational modifications such as disulfide bonds and glycosylation. Large diverse phage display libraries have been created by engineering in two nine amino acid peptide loops into the scaffold backbone. We have identified a range of affinity competitive binders to mouse or human PD-L1 confirmed by performing competition ELISA and SPR using Fc formatted antigen. Half-life extension of lead Affimer proteins was achieved by fusing to human IgG1Fc or as an in-line fusion (ILF) fused to serum albumin binding Affimers. We demonstrated avidity for binding to target antigen, binding to cells in vitro and blockade of the PD-1L/PD-1 interaction using Promega cell based assay. The PK properties of the formatted Affimers in mouse showed half-life extension from 40-120 hours depending on the clone and half-life extension technology used.
We have demonstrated that the Affimer scaffold has the necessary properties to be developed as an immunotherapy. The anti-PD-L1 Affimer scaffold proteins were formatted as Fc fusion and in-line fusion formats which showed in vivo efficacy. These molecules will be developed further for both bispecific and drug conjugates to generate new novel biotheraputics that will give greater efficacy in the clinic.
Citation Format: Amrik Basran, Emma Jenkins, Estelle Adam, Floriane Laurent, Michele Writer, Assa Oumie, Jyrki Sivula, Maureen West, Emma Stanley, Jennifer Hillman, Viviana Robles-munoz. Preclinical evaluation of half-life extended Affimer® biotherapeutics targeting the PD-L1 pathway [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4108.
Abstract 411: Rapid and sensitive detection of EGFR C797S mutations using a blood-based droplet digital PCR assay
Authors: Edwards Victoria , Jackson Leisa , Reese Jordan , Mellert Hestia S. , Pestano Gary 
Published: August 2019

Abstract
The adoption of third-generation tyrosine kinase inhibitors (TKIs) to treat non-small cell lung cancer (NSCLC) for EGFR positive patient cases has led to the emergence of acquired resistance pathways. Approximately 40% of EGFRT790M-positive NSCLC cases display an acquired mutation of amino acid 797 (C797S) that mediates this resistance, which can develop after a median of 10 months following treatment. The effectiveness of treatment for patients with EGFRC797S may depend on whether the mutation is present in cis or trans with EGFRT790M, the type of sensitizing mutation (EGFRdel19 or EGFRL858R), and previous treatment(s). Patients with EGFRdel19 or EGFRL858R in conjunction with EGFRT790M and EGFRC797S remain resistant to all current targeted therapies. Several fourth-generation inhibitors are in development but have yet to be validated in clinical trials. We have developed a blood-based test that can detect two of the most common C797S nucleotide mutations (T&gt;A and G&gt;C) in cis or trans with EGFRT790M using the droplet digital PCR (ddPCR) technology and assays. Analytic sensitivity and specificity were assessed using synthetic DNA designed to mimic the EGFRC797S variants and their locus detected in the assay. Normal healthy donors as well as reference ddPCR positive and negative NSCLC donor samples were assessed for clinical specificity and sensitivity. Finally, the precision of the assay was evaluated with both clinical and analytical samples. Specifically, we evaluated the assay at high, medium, and low mutation frequencies over three consecutive days, including repeat runs on one day, and with multiple operators. This assay is capable of accurately and precisely detecting multiple EGFRC797S variants and their locus from blood specimens in the clinical laboratory. Consistent with other ddPCR blood-based EGFR variant assays we have developed, the limit of detection was 0.02%for C797S variants detected in both cis and trans with the T790M mutation. Once validated, the EGFR C797S assay described here may be of utility in diagnosing patients who have developed resistance to osimertinib.
Citation Format: Victoria Edwards, Leisa Jackson, Jordan Reese, Hestia S. Mellert, Gary Pestano. Rapid and sensitive detection of EGFR C797S mutations using a blood-based droplet digital PCR assay [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 411.