bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 1609: Oxidative stress triggers tumor edge progression of tumor microenvironment in the minipig spinal cord glioma model
Authors: Lei Kecheng , Tora Muhibullah S. , Neill Stewart G. , Nagarajan Purva P. , Federici Thais , Canoll Peter , Boulis Nicholas M. 
Published: June 2022

Abstract
Oxidative stress is exerted by reactive oxygen species (ROS) that accumulate due to an imbalance between ROS generation and elimination, which impacts cellular metabolism and consequently tumorigenesis in the tumor microenvironment. Recently, our group has developed a spinal cord glioma (SCG) model in Göttingen minipigs. However, the mechanism of how SCGs balance redox and thereby modulate cellular proliferation is unclear. Here, we demonstrated that the NRF2/NQO1 signaling, known to mediate oxidative stress, is upregulated in unresectable SCG cells infiltrating at the leading edge compared with the core cells. Moreover, pro-inflammatory cytokines, including TNF-α, IL-1β, and IL-6, were significantly elevated in the edge SCG cells. Immunohistochemistry demonstrated positive staining for a higher Ki-67 proliferative index, GFAP, SOX2 and Olig2 in the edge cells compared to the core cells. The oxidative metabolic heterogeneity of immune and stromal cell subtypes among tumor samples was also explored. Hence, our study demonstrated the tumor microenvironment and involvement of the NRF2/NQO1 pathway for redox homeostasis in our minipig SCG model, which can be used to explore targets of the pre-clinical treatment investigations in SCG.
Citation Format: Kecheng Lei, Muhibullah S. Tora, Stewart G. Neill, Purva P. Nagarajan, Thais Federici, Peter Canoll, Nicholas M. Boulis. Oxidative stress triggers tumor edge progression of tumor microenvironment in the minipig spinal cord glioma model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1609.
Abstract 1643: B-hIL12A/hIL12B/hIL12RB1/hIL12RB2: A novel animal model for generation of IL12 therapies
Authors: Wang Linlin , Liu Chang , Chromikova Veronika , Lyu Ruili , Jin Tianquan , Kuraguchi Mari 
Published: June 2022

Abstract
The pro-inflammatory cytokine, interleukin 12 (IL12), is primarily responsible for cell-mediated immunity and is chiefly produced by antigen presenting cells. Prior preclinical studies elucidated a promising role for IL12 mediating anti-tumor effects, however, clinical studies using cancer patients showed disappointing efficacy results, as well as severe adverse effects, with administration of systemic IL12 therapies. Intriguingly, progress in targeted delivery to the tumor microenvironment renewed high expectations on IL12 as a promising anti-tumor drug either alone or in combination due to its ability to inhibit and/or reprogram immunosuppressive cell subsets. Therefore, to evaluate the efficacy of IL12 and IL12 analogs in preclinical studies, Biocytogen has successfully generated a novel hIL12A/hIL12B/hIL12RB1/hIL12RB2 knock-in mouse strain. In this mouse model, the full coding sequences (CDS) of the mouse Il12a or Il12b gene were replaced by their human counterpart IL12A or IL12B gene sequences respectively. In addition, chimeric CDS, composed of human IL12RB1 or IL12RB2 extracellular region plus mouse Il12rb1 or Il12rb2 cytoplasmic region, was inserted into the mouse endogenous gene locus in in these animals, to express an IL12 receptor (IL12R) capable of recognizing human IL12 signaling. Expression analysis by RT-PCR detected human IL12A/IL12B/IL12RB1/IL12RB2 mRNA in humanized mice but not in wild-type mice. Additionally, human IL12 p70 was successfully detected in the serum of humanized mice by ELISA. The immune cell subpopulations in spleen, blood, and lymph node did not differ between humanized mice and wild-type mice suggesting no impact on cell differentiation and maturation. Anti-tumor activity of a modified human IL12 was assessed in humanized mice bearing colon cancer MC38 cells and showed tumor inhibitory effects. Moreover, the tumor growth recovered when the administration of the drug was stopped. Altogether, B-hIL12A/hIL12B/hIL12RB1/hIL12RB2 humanized mice provide a promising preclinical efficacy model for human IL12 therapy alone or in combination. Keywords: IL12, humanized mice, antibody efficacy
Citation Format: Linlin Wang, Chang Liu, Veronika Chromikova, Ruili Lyu, Tianquan Jin, Mari Kuraguchi. B-hIL12A/hIL12B/hIL12RB1/hIL12RB2: A novel animal model for generation of IL12 therapies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1643.
Abstract 1645: Advancing the development of CD16A-based bispecific antibodies in humanized CD16A mouse models
Authors: Chang Jiahui , Li Tao , Ma Limei , Sun Xiaoxia , Shen Yuelei 
Published: June 2022

Abstract
Antibody-dependent cell cytotoxicity (ADCC) is an important mechanism in immunotherapy. CD16A (FcγRIIIA), a low-affinity receptor for the IgG Fc domain, facilitates ADCC and is responsible for triggering the lysis of target cells by natural killer (NK) cells. Human CD16A is closely related to mouse Fcgr4 and is expressed in NK cells and macrophages, but is absent in granulocytes. Alternatively, mouse Fcgr4 is expressed in granulocytes and macrophages and is absent in NK cells. CD16A-based bispecific antibodies targeting NK cells have been studied for cancer therapy. To evaluate the anti-tumor efficacy of CD16A-based bispecific antibody in mouse tumor models, we have successfully generated a novel humanized CD16A knock-in mouse strain (B-hCD16A Mice). Considering the differential expression patterns between human CD16A and mouse Fcgr4, the regulatory region and whole genome sequence of mouse Fcgr4 were replaced by the human CD16A gene. Human CD16A and mouse Fcgr4 protein expression was confirmed in heterozygous B-hCD16A mice by FACS and RT-PCR. Human CD16A protein was detected in NK cells and macrophages of B-hCD16A mice, but not granulocytes. When compared with wild type mice, there were no abnormalities in the populations of immune cells in B-hCD16A mice. CD16A-based bispecific antibody usually binds to CD16A on NK cells, whereas the other arm of the antibody binds to tumor antigen on cancer cells. Initial assessment of the tumorigenicity of MC38 cells were evaluated in B-hCD16A mice, and results indicated that these cancer cells were able to establish tumors in vivo. These data suggest that the B-hCD16A mouse model is an effective tool for future in vivo efficacy evaluation of therapeutic CD16A-based bispecific antibodies prior to clinical development.
Citation Format: Jiahui Chang, Tao Li, Limei Ma, Xiaoxia Sun, Yuelei Shen. Advancing the development of CD16A-based bispecific antibodies in humanized CD16A mouse models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1645.
Abstract 1649: Humanized PVRIG mice: A novel tool for evaluating anti-PVRIG immunotherapies
Authors: Zhang Yifu , Yao Jiawei , Soto Rebecca , Liu Chonghui , Lin Qingcong 
Published: June 2022

Abstract
The use of humanized mouse models provides a promising platform for preclinical studies aimed at developing novel immunotherapies. While current checkpoint inhibitors have improved patient outcomes, combination therapy targeting additional checkpoint receptors may heighten the immune response. Specifically, previous reports have shown that high expression of the immune checkpoint poliovirus receptor-related immunoglobulin domain-containing (PVRIG) protein leads to T-cell exhaustion. Furthermore, in vitro blockade of human PVRIG enabled T-cell activation. To explore the translational potential of inhibiting PVRIG, we evaluated the efficacy of PVRIG antibodies by generating a humanized B-hPVRIG mouse model. In this model, the mouse Pvrig gene was replaced by the human counterpart, and expression of the human PVRIG protein was confirmed in homozygous B-hPVRIG mice. Additionally, flow cytometry analysis showed similar distribution of T-cell subtypes within the blood, spleen, and lymph nodes of B-hPVRIG mice compared to wild-type C57BL/6. Lastly, our in vivo efficacy studies showed that homozygous B-hPVRIG mice that were subcutaneously implanted with murine colon cancer (MC38) cells and treated with 30 mg/kg of the human PVRIG antibody, reached a tumor growth inhibition (TGI) of approximately 40%. This data suggests that human PVRIG antibodies significantly inhibit tumor growth in homozygous B-hPVRIG mice. Altogether, our humanized B-hPVRIG mouse model is an effective tool for in vivo efficacy studies aimed at the development of novel PVRIG immunotherapies.
Citation Format: Yifu Zhang, Jiawei Yao, Rebecca Soto, Chonghui Liu, Qingcong Lin. Humanized PVRIG mice: A novel tool for evaluating anti-PVRIG immunotherapies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1649.
Abstract 1651: Generation of humanized TLR8 mice for the evaluation of human TLR8 agonists
Authors: Shen Yuelei , Guo Yanan , Kong Lingqi , Bai Yang Bai , Yao Jiawei , Shang Chengzhang , Huang Jingwen 
Published: June 2022

Abstract
Toll-like receptor 8 (TLR8) is encoded by the TLR8 gene and belongs to the family of toll-like receptors (TLRs). TLR8 is predominantly expressed in lung and peripheral blood leukocytes. Close to the TLR8 gene locus, another TLR family member, TLR7, is also located on chromosome X and potentially can be manipulated by TLR8. TLR8 is an endosomal receptor that recognizes single-stranded RNA (ssRNA) viruses. After exogenous ssRNA infection, TLR8 will recruit MyD88 and activate downstream signaling. Similarly, miRNAs secreted from tumor cells also can activate TLR8 and lead to activation of the transcription factor NF-κB. Therefore, TLR8 also has been recognized as a potential therapeutic target. TLR8 agonists (e.g. VTX-2337) are undergoing clinical trials as immune stimulants in combination therapy for some cancers. Immune-stimulating antibody conjugates (ISACs) were developed by Bolt therapeutics, comprising a TLR7/8 dual agonist conjugated to tumor-targeting antibodies. ISACs can drive tumor killing by TLR mediated activation of myeloid cells and subsequent T-cell-mediated antitumor immunity, resulting in tumor clearance and immunological memory. Although human TLR8 arises as a promising target, emerging therapeutic candidates are lacking suitable mouse models on the market for preclinical in vivo screening and efficacy evaluation. Biocytogen has developed a novel TLR8 humanized mouse model (B-hTLR8 mice). Exon 3 of the mouse TLR8 gene, which encodes the extracellular domain, was replaced by human TLR8 counterparts. Human TLR8 protein and mRNA were detected in lung tissue from homozygous B-hTLR8 mice with the absence of mouse TLR8. Additionally, human TLR8 was detectable via flow cytometry in the dendritic cells and monocytes. To further validate the model, we have examined the model in vivo with a benchmark TLR8 agonist GS-9688. We observed TNFα secretion in B-hTLR8 mice but not in wild-type mice. Therefore, B-hTLR8 mouse model is a promising model for preclinical in vivo studies to evaluate TLR8 agonists and antibody-conjugated TLR8 agonists.
Citation Format: Yuelei Shen, Yanan Guo, Lingqi Kong, Yang Bai Bai, Jiawei Yao, Chengzhang Shang, Jingwen Huang. Generation of humanized TLR8 mice for the evaluation of human TLR8 agonists [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1651.
Abstract 1652: A humanized mouse model of the promising immune checkpoint molecule B7-H4
Authors: Lyu Ruili , Liu Chonghui , Charpentier John , Zhao Suman , Yu Luke (Zhaoxue) 
Published: June 2022

Abstract
B7-H4, a member of the B7-family of immune-regulatory ligands, has emerged in recent years as a promising target for immune checkpoint therapy development. B7-family ligands bind via extracellular tandem immunoglobulin-like domains to CD28-family receptors on lymphocytes to communicate co-stimulatory or co-inhibitory signals. B7-H4 remains an orphan ligand, although evidence from knockout mice suggests a co-inhibitory role and its expression on cancer cells and tumor-associated macrophages is associated with inhibition of proliferation, cell cycle progression, and cytokine secretion in T cells. B7-H4 is highly expressed in a variety of tumors (e.g., renal, gastric, breast, and ovarian carcinomas) and plays less well-appreciated roles in autoimmune diseases, viral infections, and maternal-fetal immunity. Negative regulation of T cell responses by B7-H4 has also been shown to induce tolerance of islet allografts in mouse models of Type I diabetes. A range of B7-H4-targeted immunotherapy agents have been successfully developed, including monoclonal antibodies, antibody-drug conjugates, B7-H4/CD3-targeting bispecific antibodies, and B7-H4-specific CAR-T cells. To evaluate the efficacy of a B7-H4 antibody, Biocytogen generated humanized B-hB7-H4 mice. Our targeting strategy was to replace the murine B7-H4 extracellular domain sequences with their corresponding human sequences. We verified mRNA and protein expression of human B7-H4 in the humanized B-hB7-H4 mice by RT-PCR and Western Blot, respectively. An in vivo efficacy study demonstrated that B7-H4 antibodies significantly inhibited tumor growth in B-hB7-H4 mice bearing tumors derived from the B16-F10 murine melanoma line. These data confirm that the B-hB7-H4 humanized mouse model is a powerful tool for evaluating the preclinical potential of B7-H4-targeting immune-therapeutics. Keywords: Humanized mice, B7-H4, Immunotherapy
Citation Format: Ruili Lyu, Chonghui Liu, John Charpentier, Suman Zhao, Luke (Zhaoxue) Yu. A humanized mouse model of the promising immune checkpoint molecule B7-H4 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1652.
Abstract 1673: Establishment and characterization of pediatric brain tumor models in an orthotopic mouse model
Authors: Oswald Eva , Lashuk Kanstantsin , Gojo Johannes , Lenhard Dorothee , Mack Norman , Krausert Sonja , Lötsch Daniela , Jones David , Kool Marcel , Milde Till , Berger Walter , Pfister Stefan M. , Schüler Julia 
Published: June 2022

Abstract
Brain and spinal cord tumors are the second most common group of cancers in children. For children who experience relapses of their tumors, usually after very intensive first-line therapy, curative treatment options are scarce. Thus, the need for predictive preclinical platforms explicitly for pediatric brain tumors is an urgent need. In the framework of the ITCC-P4 public-private partnership, we thus far fully established 23 pediatric brain tumor-derived PDX models. A selection of four high grade glioma, one medulloblastoma and one ependymoma models were used to validate a protocol for fluorescence-based optical imaging. Tumor growth characteristics, latency and histopathology were evaluated for the un-transduced and iRFP713-transduced models side by side. In case of iRFP713-transduced PDX models, tumor load was determined twice a week with the Pearl trilogy system (LiCor, Germany). All animals were examined for neurological symptoms daily and body weight was examined twice a week. The latency of the tumor models ranged from 29 days to 180 days. The take rate was 100% across all the models with n=12 NSG mice per setting. The transduction did not influence the take rate, but 30 - 40% more donor material was needed due to viability loss during the overnight transduction. It was not possible to determine the transduction efficiency for iRFP713 in the overnight culture as the signal is getting upregulated only 48h - 72h post transduction, e.g., when the cells are already implanted. The signal was stable for up to 180 days in the slowest tumor model ependymoma HN0579. The fastest model, high grade glioma HG0068, reached termination criteria within 24 days. Histopathological examination was strictly correlated with the tumor load determined by optical imaging in situ and ex vivo (organ imaging). The histopathological investigation of the mouse brains displayed no differences in tumor localization, size, and invasiveness between the transduced and the un-transduced lines. The proliferation rate determined by Ki-67 staining was not influenced by the modification of the cells. Further molecular and phenotypic characterization of the transduced vs the un-transduced PDX will increase the utility of this platform for the development of new drugs and the identification of innovative drug targets.
Citation Format: Eva Oswald, Kanstantsin Lashuk, Johannes Gojo, Dorothee Lenhard, Norman Mack, Sonja Krausert, Daniela Lötsch, David Jones, Marcel Kool, Till Milde, Walter Berger, Stefan M. Pfister, Julia Schüler. Establishment and characterization of pediatric brain tumor models in an orthotopic mouse model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1673.
Abstract 1694: Cytotoxic conditions alter cell free DNA concentration and fragment size in cancer cells
Authors: Bustamante Prisca , Tsering Thupten , Burnier Julia Valdemarin 
Published: June 2022

Abstract
Introduction: Detection of circulating free DNA (cfDNA) is a promising tool to monitor and predict tumor progression and treatment efficacy. Our group has shown the clinical relevance of cfDNA as a biomarker of tumor development and progression in several cancer models, including colorectal carcinoma and melanoma. cfDNA may stem from a combination of apoptosis, necrosis, and cellular secretions. However, the source and mechanism of cfDNA release in cancer cells are still unclear. Indeed, while some data state that cfDNA is derived from apoptosis, other studies report it is mainly a product of cellular secretions. To better understand cfDNA release and its correlation with tumor biology, this study aimed to assess cfDNA kinetics under cell death, cell cycle arrest, and senescence by using an in vitro cancer model.
Methods: Colorectal (HTC116 and HT29), lung (A549), and melanoma (MP41 and OMM2.5) cancer cells underwent cytotoxic conditions by drugs: TRIAL/APO2L, Roscovitine, and valproic acid (VAP), as well as environmental stress by heat and irradiation. Cell death and cell cycle were evaluated by FACS. β-galactosidase staining assessed senescence. cfDNA was extracted from 3 mL supernatant using QIAamp nucleic acid kit and evaluated by digital droplet PCR through hot spot mutations (Mut), and a mitochondrial gene (mt-cfDNA). Isolated cfDNA was visualized by fragment size using Bioanalyzer 2100.
Results: Mut and mt-cfDNA increased during cytotoxic conditions in a dose-dependent manner. Cells under apoptosis released greater mut and mt-cfDNA compared to necrotic and untreated cells. Similarly, cell cycle disturbances by VAP were associated with an increase in Mut and mt-cfDNA. Moreover, β-galactosidase positive cells (5D post-irradiation) showed lower Mut and mt-cfDNA levels than control conditions. Electropherogram images showed that cytotoxic conditions alter fragment size distribution. While fragments about 100-200 bp were observed in apoptosis, necrosis showed more abundant fragments about &gt;1000 bp.
Conclusions: The release of cfDNA is influenced by cytotoxic and stress conditions. Knowing the biology of cfDNA can help understand its role in cancer development and how best to utilize this marker clinically, especially post cytotoxic agents that induce different cell death mechanisms. These findings have major implications in the interpretation of ctDNA in liquid biopsy as a biomarker of treatment response and tumor progression.
Citation Format: Prisca Bustamante, Thupten Tsering, Julia Valdemarin Burnier. Cytotoxic conditions alter cell free DNA concentration and fragment size in cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1694.
Abstract 1698: Copy number diversity within and across tumor types
Authors: Baker Toby , Dentro Stefan , Spellman Paul , Tarabichi Maxime , Van Loo Peter 
Published: June 2022

Abstract
Introduction Cancers commonly accrue copy number gains and losses during their development. An improved understanding of their contribution to tumorigenesis can be gained by studying their distribution and evolution within and across tumor types.
Materials and Methods We analyzed copy number profiles of 16,765 tumours from the Hartwig Medical Foundation, Pan-Cancer Analysis of Whole Genomes (PCAWG) and The Cancer Genome Atlas (TCGA) cohorts. We used a novel timing method, ComplexTiming, to time the occurrence of copy number gains, and a permutation-based approach to assess the distribution of copy number events relative to a null distribution.
Results Complex copy number states in cancers that have undergone a whole-genome duplication (WGD) are commonly assumed to develop through a most parsimonious route, where the series of events leading to the complex copy number state requiring the least number of steps, is proposed to be the most likely one. Our newly developed ComplexTiming approach allows unique insights into the actual routes that led to these complex copy number states. In our large pan-cancer cohort, we found that the most parsimonious set of events does not occur in approximately 40% of cases. Additional gains more frequently occurred after WGD than before, reflecting a previously observed increase in instability. In squamous cell lung cancer, gains of 3q were frequently found before WGD. Additionally, 5q and 1q were significantly more likely to be gained before WGD in colorectal and melanoma metastases, respectively.
Evaluating the distribution of copy number events, we found that the majority of copy number events are distributed across tumors consistent with a permutation model that assigns copy number events randomly. However, interestingly, in the majority of cancer types, we found copy number events that occurred more often than expected in individual tumors with low numbers of events, such as loss of chromosome 9 in bladder cancer, loss of 20p in colorectal adenocarcinomas, and gain of 1q in breast adenocarcinomas. These results suggest that the high-frequency of these specific copy number events is due to selection, while other copy number changes may occur neutrally due to innate chromosome instability.
Conclusion The landscape of copy number gains in tumors is diverse. By analyzing the timing of these events as well as their distribution, we identify a subset of frequent copy number changes in different cancer types that are likely under selection.
Citation Format: Toby Baker, Stefan Dentro, Paul Spellman, Maxime Tarabichi, Peter Van Loo. Copy number diversity within and across tumor types [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1698.