bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 2945: Novel engineered B-NDG B2M/KO mice plus and steroid treated B-NDG Mice shows delayed GvHD response when engrafted with hPBMC
Authors: Gao Lan , Sharma Shruti , Lin Eugene , Wang Xiaoen , Shang Chengzhang , Hu Yuting , An W. Frank , Chawla Mehma Kaur , Li Kaiqi , Lin Qingcong , Yu Zhaoxue (Luke) , Liu Yujie 
Published: July 2021

Abstract
Severely immunodeficient mouse strains, such as NOD.Cg-Prkdcscid Il2rg-/-, have been used to study the immune response in humans. These mice lack T, B and natural killer (NK) cells and allow for engraftment of human peripheral blood mononuclear cells (PBMCs). However, hPBMC engraftment may lead to severe acute xenogeneic graft versus host disease (GvHD) which arises due to a response from T cells against human leukocyte antigens (HLA) that are encoded by major histocompatibility complex (MHC) class I and II. GvHD shortens animal life span and results in only a brief window of evaluation of human immune cell functions in such mouse models. Efforts have been undertaken to reduce human PBMC-induced GvHD and to subsequently extend the window of human immunity assessment by eliminating mouse MHC I and MHC II. While these beta-2-microglobulin (B2M) knockout mice which are MHC deficient showed fewer symptoms of GvHD, an unintended result was the shorter half life of the antibodies which lead to its rapid clearance. This occurred because B2M is also associated with neonatal Fc receptor (FcRn) and is important to FcRn-mediated in vivo antibody recycling and retention. This is a pharmacokinetic limitation because it renders antibody efficacy assessment and makes these mice unsuitable for studying immune responses. To overcome this limitation, we engineered B-NDG B2M knockout mice plus (NOD.Cg-Prkdcscid Il2rg-/-/Bcgen) that is deficient in MHC I expression but expresses the B2M gene fused in the FcRn gene. In the present study we demonstrate the phenotypic changes in the immune system of the engineered mice using flow cytometry and validate immune tolerance developed over the several weeks of post engraftment by looking at the homeostatic balance between CD8/Treg ratio in the partially reconstituted humanized immune systems. In a parallel study, we used corticosteroid treatment in hPBMC induced B-NDG mice GvHD model. Corticosteroids are the fine line of therapy for GvHD and the phenotypic response generated in B-NDG mice confirms this finding in our GvHD model.
Citation Format: Lan Gao, Shruti Sharma, Eugene Lin, Xiaoen Wang, Chengzhang Shang, Yuting Hu, W. Frank An, Mehma Kaur Chawla, Kaiqi Li, Qingcong Lin, Zhaoxue (Luke) Yu, Yujie Liu. Novel engineered B-NDG B2M/KO mice plus and steroid treated B-NDG Mice shows delayed GvHD response when engrafted with hPBMC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2945.
Abstract 2951: Anti-GCGR in vivo efficacy evaluated in a novel humanized B-hGCGR mouse model
Authors: Zhang Rufeng , Shang Chengzhang , Hu Yuting , Chromikova Veronika , Lin Qingcong 
Published: July 2021

Abstract
GCGR (glucagon receptor) is a G-protein-coupled seven-transmembrane protein, a typical representative of the class B GPCR family. Animals homozygous for a targeted mutation in this gene exhibit reduced blood glucose levels, increased plasma glucagon and amino acid levels associated with alpha-cell hyperplasia. Glucagon activates intracellular adenylate cyclase by specifically binding to GCGR on the surface of target cells in the liver. This results in an increase in intracellular cAMP levels, playing a role in promoting glycogenolysis and gluconeogenesis, and promoting blood glucose elevation. The crucial role in regulation of blood glucose levels and glucose homeostasis is posing GCGR as a potential drug target for type 2 diabetes and related diseases. Currently, much attention and many resources are directed towards research and development of antibody drugs targeting the glucagon receptor. Joining these efforts, Biocytogen has developed a GCGR humanized mouse model (B-hGCGR mouse). Human GCGR protein and mRNA were detected in liver tissue of homozygous B-hGCGR mice, but not in wild type mice. Physiological indexes have been analyzed. Results indicated that the random blood glucose, fasting blood glucose, and glucose tolerance were comparable to the wild type mice. In addition, we characterized the ability of glucagon to stimulate production of cAMP. We observed that glucagon elicits a dose specific increase of cAMP in membranes prepared from the humanized GCGR mice comparable to the cAMP levels observed in membranes prepared from wild type mice. In pharmacodynamic experiments using B-hGCGR mice we showed that an anti-GCGR antibody (Crotedumab) was able to effectively reduce random blood glucose and fasting blood glucose levels and improve the glucose tolerance, validating our humanized mouse model. This antibody also blocked the functional response to glucagon in B-hGCGR mice more efficiently than what can be observed in an approach targeting the wild type murine receptor using antagonists. These data demonstrate that B-hGCGR mice are a promising model for preclinical in vivo pharmacodynamic assessment of anti-GCGR antibodies.
Citation Format: Rufeng Zhang, Chengzhang Shang, Yuting Hu, Veronika Chromikova, Qingcong Lin. Anti-GCGR in vivo efficacy evaluated in a novel humanized B-hGCGR mouse model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2951.
Abstract 2953: Humanized IL6/hIL6R mouse model supports the evaluation of therapeutic drug candidates targeting to human IL6 and IL6 receptor
Authors: Zhao Lei , Mao Yang , Wang Linlin , Chen Yichao , Kokabee Leila , Lin Qingcong 
Published: July 2021

Abstract
Interleukin 6 (IL-6) gene encodes a cytokine that functions in inflammation and the maturation of B cells and is a potent pleiotropic cytokine that regulates cell growth and differentiation and plays an important role in the immune response Evidence of recent research shows blockade of IL-6 and IL-6 receptor interaction can offer a broader therapeutic strategy for various diseases included in acute systemic and chronic inflammatory diseases. The development of humanized mouse model can greatly support preclinical evaluation of human IL6 and IL6 receptor therapeutic drugs. To evaluate the efficacy of IL-6 and IL-6R therapeutic drug candidates, Biocytogen has generated a double humanized B-hIL6/hIL6R mouse model. In this model, the mouse IL6 gene that encodes the full length was replaced with the corresponding human sequences and the CDS of human IL6R gene was inserted into the IL6RA gene in B-hIL6/hIL6R mice. Human IL6 or IL6R protein expression was detected in homozygous B-hIL6/hIL6R mice by species-specific IL6 ELISA kit, also evaluated by flow cytometry. In efficacy study of anti-human IL6 antibodies in B-hIL6/hIL6R mice with collagen induced arthritis (CIA) , the IL6 antibody treatment reversed the disease progression by decreasing the total clinical score compared to the control group. The efficacy suggests that the B-hIL6/hIL6R mouse model is an effective tool for in vivo efficacy study in the development of IL6 and IL6R antibodies which provide a promising potential in future human clinical trials.
Citation Format: Lei Zhao, Yang Mao, Linlin Wang, Yichao Chen, Leila Kokabee, Qingcong Lin. Humanized IL6/hIL6R mouse model supports the evaluation of therapeutic drug candidates targeting to human IL6 and IL6 receptor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2953.
Abstract 2958: Drug induced resistant tumor models enable the development of next-generation anticancer therapeutics
Authors: Ni Ting , Zhang Zhixiang , Tang Xuzhen , Shi Wenting , Gu Qingyang , Ji Qunsheng 
Published: July 2021

Abstract
Recent advances in cancer biology and diagnosis are providing more targeted approaches to treat cancers. Therapy targeting the specific oncogenic driver could inhibit tumor progression and helps to a favorable prognosis in clinical practice. Recently, the discovery of driver mutations in various cancers such as EGFR, ER, CDK, c–MET, TRK and BTK provides a personalized targeted treatment. However, most patients who initially benefit a lot from targeted therapies eventually become resistant to treatments. Acquired resistance limits the long–term efficacy. The commonly acquired resistant mechanisms include target gene mutation, alternative pathway activation, histological or phenotypic transformation and so on. Although a variety of mechanisms of acquired resistance have been reported, optimal treatment for acquired resistance is not yet clearly defined.
To mimic the clinical resistant after long–term treatment, we established a panel of in vivo induced drug resistant CDX and PDX models by continuous dosing of targeted drugs to mice, covering a series of first–line targeted drugs Tamoxifen, Olaparib, BMN–673, Ibrutinib, Crizotinib, Erlotinib, Palbociclib, Capmatinib, Entrectinib, Cabozantinib, Sorafenib and Irinotecan. Resistant models were derived from sensitive models harboring specific oncogenic driver. Regrowth tumors were continually treated with targeted drugs and passaged several times until a stable drug resistance phenotype occurred. To explore the resistant mechanisms, we performed WES and RNA–seq analysis in the gene expression levels, and western blotting and IHC staining in the protein expression levels. In summary, these drug induced resistant tumor models provide an opportunity to evaluate the next–generation anticancer therapeutics to overcome therapeutic resistance in tumors.
Citation Format: Ting Ni, Zhixiang Zhang, Xuzhen Tang, Wenting Shi, Qingyang Gu, Qunsheng Ji. Drug induced resistant tumor models enable the development of next-generation anticancer therapeutics [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2958.
Abstract 2964: Immuno-reactive cancer organoid models to examine microbiome metabolite effects on immune checkpoint blockade efficacy
Authors: Shelkey Ethan , Soto-Pantoja David , Lu Yong , Soker Shay 
Published: July 2021

Abstract
Introduction: As the number of available immunotherapies for solid tumors increase, their prevalence in the clinic continues to rise as well. While the results are promising, and immunotherapies have benefits over traditional chemotherapeutics, a sizable percentage of patients are non-responders to all types of immunotherapy. These differences in sensitivity can be either innate or acquired. Yet, there has been limited 3D in vitro models to assess tumor immune-reactivity. These systems are ideal for isolating specific molecular mechanisms that dictate cell behavior and interactions. Our goal was to create an organoid model containing cancer cells paired with cytotoxic T-cells to model immune checkpoint blockade (ICB) efficacy. This model could then be used to examine novel microbiome-ICB interactions shown by recent research to alter therapeutic response levels in patients.
Methods: We created tumor organoids consisting of tumor and immune cells, embedded in extracellular matrix (ECM)-like hydrogels. Organoids were treated with therapeutic equivalent doses of anti-PD-1 and anti-CTLA-4 or single dose of anti-CD-47 and cell viability assays, flow cytometry, RT-qPCR, and immunohistochemistry staining were performed to determine the effects of ICB. Physiologic concentrations of metabolites derived from likely effector bacterial species were then evaluated for their effects on genetic expression and immunotherapy efficacy.
Results and Discussion: We showed that ICB therapy stimulated internally localizing T-cells, inducing T-cell-mediated tumor cell killing. ICB treated samples resulted significant loss of viability with corroborating readings from the other methods of characterization. RT-qPCR resulted in some elucidation of potential cellular changes due to bacterial metabolites with further quantification ongoing.
Conclusion: We have created an ex-vivo tumor immune-reactive organoid model for studying immunotherapy. We can now continue to change individual microenvironment factors, such as microbiome metabolites, and observe their impacts on immunotherapy efficacy to better understand what conditions are conducive or detrimental to successful ICB treatment.
Citation Format: Ethan Shelkey, David Soto-Pantoja, Yong Lu, Shay Soker. Immuno-reactive cancer organoid models to examine microbiome metabolite effects on immune checkpoint blockade efficacy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2964.
Abstract 3006: Melanoma cell lines derived from patient derived xenografts (PDX) can contain murine chromosomes resultant from cell fusions
Authors: Vega-Crespo Agustin , Baselga-Carretero Ignacio , Perez-Garcilaso Ivan , Jilani Sameeha , Chen Kevin , Khullar Vaneet , Medina Egmidio , Teper Yaroslav , Ribas Antoni , Comin-Anduix Begoña 
Published: July 2021

Abstract
Introduction: Patient Derived Xenografts (PDX) provide a distinct platform to generate in vivo and ex vivo cell lines to investigate novel therapies. However, human-murine cell fusions may skew the models and is a poorly characterized phenomenon.
Methods: Malignant melanoma IRB-consented biopsies [IRBs: 17-000548; 17-001685; 17-001351; 11-003254] were excised from various sites and implanted into gender-matched 4-6 weeks old NOD-scid IL2Rgammanull mice. Tumor-bearing mice were humanely euthanized and adherent cell lines were generated after Miltenyi gentleMACS™ dissociation of the PDXs. Briefly, adherent cells are allowed to proliferate and passaged when 70% confluent for approximately 4-8 weeks. PDX-derived cell products were processed for long term-cryostorage and an aliquot was sent for GenePrint 10 System-Promega®-LaragenTM cell line authentication paired with patient-matched peripheral blood mononuclear cells (PBMC) for specimen congruency. Mouse-genome contaminant resulting cultures were prepared and sent for cell line characterization by G-banded metaphase karyotyping-Cell Line GeneticsTM. Cultures containing murine karyotypes were processed according to manufacturer recommendations by Miltenyi Mouse Cell Depletion KitTM where the flow through (negative fraction) represents the human-cell fraction.
Results: We implanted 86 patient-derived biopsies into mice over 3years, from which 39 [45%] resulted in progressively growing PDXs. From these PDXs we have generated 26 [37%]-patient-specific PDX-derived cell lines. G-banded metaphase karyotyping demonstrated that 6 [24%]- cell lines presented murine chromosome contamination. The immunoprofile of these 6 cellular materials appear to be murine as the totality of the cultures were sequestered in the column by mouse depletion cell cocktail. Separation assay was validated by bonafide human cell lines, utilized as human positive controls, M257 and MX210 both with human karyotypes and matched Cell ID profiling. The murine colon carcinoma cell line MC38, was utilized as a positive murine control, and performed identically as the 6 PDX-derived cellular materials with abnormal mouse genomes.
Conclusion: Detection of murine-human fusion cells in cell lines derived from PDXs may limit the utility of these models.
Citation Format: Agustin Vega-Crespo, Ignacio Baselga-Carretero, Ivan Perez-Garcilaso, Sameeha Jilani, Kevin Chen, Vaneet Khullar, Egmidio Medina, Yaroslav Teper, Antoni Ribas, Begoña Comin-Anduix. Melanoma cell lines derived from patient derived xenografts (PDX) can contain murine chromosomes resultant from cell fusions [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 3006.
Abstract 3019: An ultra-accurate NGS assay reveals great variation in mouse ratios in xenograft tumors by mouse strain and cancer type
Authors: Qian Wubin , Guo Sheng 
Published: July 2021

Abstract
Background: Tumors are infiltrated by stromal cells including fibroblasts, myofibroblasts, macrophages, lymphocytes, mast cells, endothelial cells, etc. Heterotypic interactions, such as ligand-receptor signaling, between the two support the growth and metastasis of cancer cells. Xenograft models are useful in studying such interactions because mouse stromal cells quickly replace the human counterparts associated with human tumors implanted in immunocompromised mice, and can be readily detected. There is, however, a lack of accurate and large-scale studies of human/mouse ratios in xenograft tumors, although there are several ways of estimating mouse ratios in xenograft tumors, including RT-PCR, RNA-seq and whole-exome sequencing (WES). None of these methods is accurate due to some systematic bias. For example, RT-PCR compares the expression of one or a few genes, e.g. GAPDH, between human and mouse by using species-specific primers that have inequivalent amplification efficiency and large errors. We have developed a NGS assay to quantify human/mouse ratios in human-mouse mixtures more accurately than the methods currently employed.
Methods: Our NGS assay simultaneously amplified 108 human and mouse homologous segments, each with identical flanking sequences in human and mouse, so that a pair of common primers was designed to have equal hybridization efficiency in the two species. A total of 5000 tumors from our patient-derived xenograft (PDX) collection were profiled across 1674 models in 24 cancer types.
Results: Several interesting observations were identified. (a) The average mouse content across the collection of PDX models was 23%, but with great variation, ranging from zero to 93%. (b) PDXs have significantly more mouse content in BALB/c than in NOD/SCID mice (31.9% vs 22.1%, p value&lt;2.2e-16). (c) Different cancers have varied mouse content, for example, pancreatic cancer has much higher mouse content than colorectal cancer (37.3±16.6% vs 17.9±12.2%). (d) Different passages of the same PDX model can have very different mouse ratios and this is likely due to randomness in tumor dissection.
Conclusions: Our NGS assay and findings will help the study of stroma and the tumor microenvironment of tumors in xenografts models.
Citation Format: Wubin Qian, Sheng Guo. An ultra-accurate NGS assay reveals great variation in mouse ratios in xenograft tumors by mouse strain and cancer type [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 3019.
Abstract 3023: B7 H3 and autophagy in medulloblastoma
Authors: Kesaf Ayse E. , Shishido Katherine , Velpula Kiran K. , Asuthkar Swapna 
Published: July 2021

Abstract
B7-H3 and Autophagy in Medulloblastoma (MB) is the most common malignant pediatric brain tumor and we reported high expression of the immune checkpoint protein, B7-H3. We also showed that B7-H3 promotes exosome secretion, with a plausible cross-talk between exosomes and autophagy in tumor development. Autophagy promotes or suppresses tumorigenesis but its role in pediatric brain tumors has not be elucidated. As our recent research has shown, the elevated levels of B7-H3 in MB enhances exosome secretion that may regulate autophagy processes favoring tumorigenesis over tumor suppression. Therefore, the goal of this study is to investigate the relationship between B7-H3 and autophagy pathways in MB in efforts to improve treatment options and patient survival. Datamining studies conducted using MB patient datasets showed a negative correlation between B7-H3 and autophagy markers; Beclin1, LC3, and ATGs. Kaplan-Meier analysis further demonstrated an inverse relationship between autophagy markers and B7-H3 in the survival curves. Next, using human autophagy array, we observed significant reduction in the expression of Beclin1, LC3, and ATGs upon B7-H3 overexpression in D425 cells. In a separate experiment, we show that silencing B7-H3 using specific shRNA resulted in increased levels of LC3-II. Functional studies performed using FACs analyses and clonogenic assay on shB7-H3 treated- D425, UW228 cells revealed that inhibition of B7-H3 was associated with augmented apoptosis and reduction in colony formation, respectively. These results demonstrate the negative role of B7-H3 in MB autophagy regulation. Therefore, inhibition of B7-H3 may prove effective at promoting autophagy-mediated cell death in MB cells.
Citation Format: Ayse E. Kesaf, Katherine Shishido, Kiran K. Velpula, Swapna Asuthkar. B7 H3 and autophagy in medulloblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 3023.
Abstract 3036: ALK protein expression and its prognostic significance in MYCN non amplified neuroblastoma
Authors: Aravindan Natarajan , Somasundaram Dinesh Babu , Shanmugarama Santny , Aravindan Sheeja 
Published: July 2021

Abstract
Anaplastic lymphoma kinase (ALK) point mutations (within the kinase domain), gene amplification and protein overexpression are identified (8-14%) both in familial and sporadic high-risk neuroblastoma (HR-NB). ALK mutations are much more frequent at time of relapse and were associated with poor clinical outcomes for children with HR-NB. Evidently, ALK is near exclusively co-amplified with MYCN, and the cooperative activity of ALK and MYCN are known to drive HR-NB pathogenesis. However, the ALK protein expression and its role in the prognosis of MYCN non-amplified NB remained unexplored. In this study, NB tumors representing varied stages, ages, sites, diagnosis/progressive disease, primary/metastatic site from a cohort MYCN non-amplified NB patients (n=92) were custom archived in TMAs and stained with ALK (immunohistochemistry) antibody. The correlations between ALK protein expression, and clinico-pathological and biological variables of MYCN non-amplified NB tumors were analyzed. Assessing the strong positivity, high expression of ALK protein could be detected in 47 (51%) of the 92 NB tumors. The majority of NBs with evident of ALK protein high expression exhibited undifferentiated or poorly differentiated histology (39/47, 82.9%). ALK protein high expression significantly predicted worse survival outcomes for NB (and HR-NB subset) patients with MYCN non-amplified status. Transcriptional data mining (R2: Genomics Analysis and Visualization Platform) across multiple cohorts of MYCN non-amplified NB patients revealed unique and defined associations of ALK to the adverse clinical prognostic factors (e.g. advanced disease stage, risk) and poor survival outcomes. Our study recognized the prognostic role of ALK protein expression in MYCN non-amplified NB. Since, ALK is indicated to transactivate MYCN, increase MYCN protein expression, and coordinate disease progression; further studies are warranted to define the mechanism(s) of ALK high-expression associated disease evolution in MYCN non-amplified HR-NB.Funding: This work was partially or in full, funded by Oklahoma Center for the Advancement of Science and Technology, OCAST-HR19-04; National Institutes of Health, NIH-P20GM103639 and; NIH-NCI- Cancer Center Support Grant P30CA225520
Citation Format: Natarajan Aravindan, Dinesh Babu Somasundaram, Santny Shanmugarama, Sheeja Aravindan. ALK protein expression and its prognostic significance in MYCN non amplified neuroblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 3036.