bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 5187: VistaPlex immunofluorescence assay panels provide reliable deep spatial phenotyping for diverse immuno-oncology applications
Authors: Christians Arne , Jackson Charles E. , Boog Jannik , Ingalls Matthew H. , Northcutt Adam , Cashion Kayla E. , Rauer Jonah , Kwarta Karen , Schwarz J Spencer , Braubach Oliver 
Published: March 2024

Abstract
Multiplex immunofluorescence (mIF) is a powerful tool that enables deep phenotyping of immune and cancer cells across a wide variety of tissue types. The initial effort and cost required to develop high-plex mIF panels is significant and poses a considerable hurdle for adoption of spatial biology. To streamline high-plex assay development, we developed a process for creating and validating multiplex antibody panels for use in immuno-oncology applications that leverage CellScape™, an automated end-to-end platform for Precise Spatial Multiplexing. Our multiplex assay development was a rigorous, multi-stage, iterative process to evaluate antibodies for suitability, specificity, and reproducibility. These assay panels are formulated as ready-to-use VistaPlex™ assay kits and are intended to enable rapid, reliable spatial phenotyping of key immune populations.
To confirm the utility of VistaPlex, we deployed the Human FFPE Spatial Immune Profiling Panel to stain and image various FFPE tissue samples on the CellScape platform. With CellScape, tissues are mounted in enclosed fluidic chambers while on-instrument staining, imaging and signal erasure are conducted in iterative rounds. The panel presented here contains antibodies against 16 common biomarkers used in immune-oncology applications. Among these are CD3, CD4, CD8, CD20, and CD45 to detect cell lineages, PD-1 and PD-L1, to interrogate immune checkpoints, and markers that inform about cell state and activation. Spatial immune profiling data were obtained from human tonsil, colon, breast, and lung tissue samples. Deep immune phenotyping was performed using unsupervised clustering analysis and AI-assisted cluster labelling, and biomarker distributions were studied in the context of cellular neighborhoods and other proximity analyses. Overall, we identified more than 19 cell phenotypes with varying frequencies and spatial arrangements across tissue samples.
Our data are robust and demonstrate that VistaPlex Assay kits for spatial profiling present an efficient and cost-effective solution for users that want to break into spatial biology.
Citation Format: Arne Christians, Charles E. Jackson, Jannik Boog, Matthew H. Ingalls, Adam Northcutt, Kayla E. Cashion, Jonah Rauer, Karen Kwarta, J Spencer Schwarz, Oliver Braubach. VistaPlex immunofluorescence assay panels provide reliable deep spatial phenotyping for diverse immuno-oncology applications [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5187.
Abstract 5194: Pre-operative markers extracted from extracellular vesicles related with lung cancer relapse
Authors: Koba Hayato , Nanjo Shigeki , Yano Seiji 
Published: March 2024

Abstract
Background: Pre- and post-operative immunotherapy have been a new standard of care for lung cancer patients. On the other hand, post-operative Osimertinib; EGFR-TKI therapy had obtained new evidence to the EGFR mutant lung cancer patients. Both treatments revealed to make patient survival prolonged. However, there are quite a lot patients who had experienced disease relapse, despite of multimodal therapy. Extracellular vesicles (EVs) have reported to have potent for searching a new target to cancers.
Purpose: Exploration of novel risk factors related with post-operative recurrence of lung cancer.
Methods: We retrospectively examined patient background, disease-free survival, overall survival, and preoperative liquid biopsy analysis in lung cancer patients who underwent surgery at Kanazawa University Hospital between January 2017 and May 2020, in whom preoperative chemotherapy was not administered. EVs were extracted from 500 μl serum within 7 days before surgery using MagCapture Exosome isolation Kit PS Ver.2 (FUJIFILM). First, we focused the six cases that had the 3 phase samples: preoperative, disease free and relapse phase. According to the EV concentrations calculated by BCA method, comprehensive protein assessment of these subjects was performed using shotgun mass spectrometry. Secondly, all cases’ prognosis were analyzed in connection with the detected marker using Dot blotting.
Results: All EV samples from primary 6 cases were able to be detected and median concentration of those was 27 μg/ml (9-82). We focused on three factors (LCEV1-3) among the 6 cases analysis, when we disease fluctuation. Among LCEV1-3 examination to all preoperative samples, LCEV2 had been related with disease recurrence.
Discussions: EVs contain amount of information such as cancer biomarker. Not only that, these factors may have a potency for therapeutic target. Further investigations are needed.
Citation Format: Hayato Koba, Shigeki Nanjo, Seiji Yano. Pre-operative markers extracted from extracellular vesicles related with lung cancer relapse [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5194.
Abstract 5271: Pseudohypoxia by HIF-PHD inhibitors activates tumor immune response for MSS colorectal cancer
Authors: Ohara Toshiaki , Chen Yuehua , Hamada Yusuke , Nishimura Seitaro , Kawai Hotaka , Noma Kazuhiro , Tazawa Hiroshi , Fujiwara Toshiyoshi , Matsukawa Akihiro 
Published: March 2024

Abstract
Purpose: Microsatellite-stable (MSS) colorectal cancer is resistant for immune therapy, necessitating the exploration of novel modalities for its conquest. Recent revelations have revealed the genetic upregulation of HIF-1α as a potential activator of CD8+ T-cells, enhancing an anti-tumor effect. Pseudohypoxia, characterized by normoxic upregulation of Hypoxia-Inducible Factor (HIF-1α), is known to be induced by iron chelators, including HIF-PHD inhibitors. In this study, we aimed to examine whether pseudohypoxia by HIF-PHD inhibitor can enhance immune response and elucidate the underlying mechanism.
Method: Colon 26, SW480 and HT29 were used as murine and human MSS colorectal cancer model. Human and murine CD8+ T-cells were represented by Jurkat cells and isolated splenic CD8+ T-cells, respectively. HIF-PHD inhibitors Roxadustat and Vadadustat were used in the study, and a subcutaneous Colon 26 tumor model was established in BALB/c WT and nude mice. Hypoxic culture conditions were maintained for 48 hours at 2% O2.
Results: Roxadustat and Vadadustat did not suppress the proliferation of cancer cells under conditions marked by HIF-1α upregulation. Roxadustat and Vadadustat suppress the colon 26 subcutaneous tumor growth in WT mice, the effect was cancelled in the nude mice. The treatment regimen was associated with an augmentation in the total number and effector-like subtypes of CD8+ T-cells (Tex) infiltrating the tumor. Combination therapy involving Roxadustat and PD-1 antibody synergistically inhibited tumor growth and was accompanied by an increase in PD-1lo, Ly108-, TIM-3+ CD8+ T-cells within the tumor microenvironment. Immunohistochemistry revealed that Interleukin-2 (IL-2) expression of murine spleen was stronger in Roxadustat than control group. Interestingly, HIF-PHD inhibitors induced the secretion of IL-2 from isolated CD3+ T-cells of murine spleens in ELISA, a phenomenon uniquely observed under pseudo-hypoxic conditions created by HIF-PH inhibitors, rather than actual hypoxia. This result indicates that pseudo-hypoxia may induce more robust hypoxic response than real hypoxia.
Conclusion: The induction of pseudohypoxia by HIF-PHD inhibitors activates the tumor immune response for MSS colorectal cancer via induction of splenic IL-2.
Citation Format: Toshiaki Ohara, Yuehua Chen, Yusuke Hamada, Seitaro Nishimura, Hotaka Kawai, Kazuhiro Noma, Hiroshi Tazawa, Toshiyoshi Fujiwara, Akihiro Matsukawa. Pseudohypoxia by HIF-PHD inhibitors activates tumor immune response for MSS colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5271.
Abstract 5273: A novel immunogenic cell death that exploits the cancer-specific overexpression of Rad51
Authors: Soloveychik Maria , Chahwan Charly 
Published: March 2024

Abstract
Overexpression of the Homologous Recombination (HR) DNA repair pathway is often correlated with poor prognosis and metastatic disease. SyntheX developed STX100, a small, stabilized peptide that is able to disrupt the function of Rad51 - a crucial component of HR. STX100 exhibits low nanomolar affinity to the target, cell permeability, and proteolytic stability. STX100 has acute mono-agent activity that is selective towards HR-overexpressing cancer cells. Interestingly, STX100-mediated cell killing is independent of canonical cell death mechanisms (apoptosis, necroptosis, pyroptosis, ferroptosis, etc.). Rather, the elevated abundance of Rad51 in cancer cells relative to healthy tissues underlies the selective cytotoxicity resulting from an acute calcium surge upon STX100-mediated target engagement. The mechanism translates to in vivo models, where a single dose can achieve sustained survival when administered locally as a mono-therapy or in combination with an immune checkpoint blockade agent.
Citation Format: Maria Soloveychik, Charly Chahwan. A novel immunogenic cell death that exploits the cancer-specific overexpression of Rad51 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5273.
Abstract 5343: Depletion of gut microbiota with broad spectrum antibiotics drives Pten-null prostate cancer growth in mice
Authors: De Velasco Marco A. , Kura Yurie , Sakai Kazuko , Nishimoto Mitsuhisa , Mori Yasunori , Yoshimura Kazuhiro , Fujita Kazutoshi , Nishio Kazuto , Uemura Hirotsugu 
Published: March 2024

Abstract
Gut microbes have the potential to be either promoters or inhibitors of cancer. Use of antibiotics during cancer therapy can lead to dysbiosis, which may affect treatment outcomes. Here, we examine the effects of broad-spectrum antibiotics on cancer progression in mice with Pten-null castration resistant prostate cancer (CRPC). After five or eight weeks, orchiectomized conditional Pten-null knockout (KO) mice aged 50 and 90 weeks were given two biweekly cycles of a broad-spectrum antibody cocktail (BSAbx), respectively. The effects of BSAbx on tumor burden were compared, and molecular and immunological responses were analyzed by quantitative IHC (qIHC) and qRt-PCR at week four after antibiotic treatment. BSAbx treatment resulted in tumor burdens of 1.2 and 2.4-fold higher than in control mice in mice aged 50 and 90 weeks, respectively. qIHC analysis of KI67 showed increased proliferation in stromal and cancer cells. Additionally, androgen receptor (AR) protein and gene expression levels of Ar and Ar target genes (Fkbp5, Tmprss2, and Timp4) were elevated in tumors of BSAbx-treated mice. Restoring gut microbiota by fecal microbiota transplantation (FMT) from KO mice CRPC after BSAbx restored AR transcriptional activity to basal levels and lessened tumor growth. FMT from non-castrated KO with castration-naïve prostate cancer or heathy wildtype mice further reduced AR Transcriptional activity. Moreover, altering the gut microbiota of CRPC mice with FMT from heathy mice resulted in a tendency for lower tumor burden, 21% reduction versus control mice. Immunologically, BSAbx treatment resulted in decreased CD11b+/GR1+ cells in tumors and were associated with decreased interferon-gamma (IFN-gamma), dendritic cell functions and T cell-mediated cytotoxicity gene signatures. Mice that received FMT form health mice showed enhanced T cell mediated immunity as demonstrated by higher IFN-gamma signatures and tumor abundances of CD8+ T cells expression IFN-gamma, TNF-alpha and the cytotoxic granule granzyme B. Our study shows that broad spectrum antibiotics caused dysbiosis and promoted prostate cancer growth in mice with Pten-null prostate cancer. The effects were partly mediated through the upregulation of AR signaling and the impairment of neutrophil and T cell-mediated immune responses in tumors.
Citation Format: Marco A. De Velasco, Yurie Kura, Kazuko Sakai, Mitsuhisa Nishimoto, Yasunori Mori, Kazuhiro Yoshimura, Kazutoshi Fujita, Kazuto Nishio, Hirotsugu Uemura. Depletion of gut microbiota with broad spectrum antibiotics drives Pten-null prostate cancer growth in mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5343.
Abstract 5346: A novel humanized CD16A model to evaluate efficacy of human antibody therapeutics in triggering ADCC
Authors: Liu Xiao , Niu Zhenlan , Lv Ruili , Lin Qingcong , Kuraguchi Mari , Xu Qingqing 
Published: March 2024

Abstract
Antibody-dependent cellular cytotoxicity (ADCC) is a mechanism by which immune effector cells engage the Fc portion of antibodies bound to antigen on the surface of another cell, thereby targeting that cell for destruction. In mice, the Fcgr4 receptor is primarily responsible for triggering ADCC, while the FCGR3A receptor (CD16A) mediates this function in human NK cells, which are an attractive target cell type for cancer immunotherapy. Given these differences, we sought to generate humanized CD16A preclinical models to evaluate the efficacy of antibodies in triggering human CD16A-mediated ADCC in vivo. Previously, we established humanized CD16A mice on immunocompetent backgrounds for evaluating efficacy of novel antibodies in preventing growth of syngeneic tumor models. Here, we introduce a novel humanized CD16A mouse on the CB-17-SCID background, in order to inoculate human tumor cells for therapeutic efficacy testing. We confirmed expression of CD16A in human NK cells and monocytes/macrophages, but not granulocytes in the model; expression of murine Fcgr4 was no longer detectable, indicating successful generation of the model. Assessment of leukocyte populations in the humanized model indicated no significant alterations in the percentages of NK cells, dendritic cells, granulocytes, monocytes and macrophages in the spleen or blood of the humanized mice compared with wild-type CB-17 SCID mice. Subsequently, the ability of these mice to grow human tumor cells was evaluated: B-hHep3B-Luc, HC116, K-562, and NCI-N87 tumors were all successfully established. Finally, efficacy of an anti-human CLDN18.2 antibody was evaluated against B-hCLDN18.2 BxPC-3 tumors in the humanized mice, which showed modest anti-tumor efficacy at 30 mg/kg when compared to isotype control-treated mice. In summary, humanized B-hCD16A mice (CB-17-SCID) provide a suitable model for evaluating the ability of antibody candidates to induce ADCC.
Citation Format: Xiao Liu, Zhenlan Niu, Ruili Lv, Qingcong Lin, Mari Kuraguchi, Qingqing Xu. A novel humanized CD16A model to evaluate efficacy of human antibody therapeutics in triggering ADCC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5346.
Abstract 5355: A novel subset of Treg-like MDSCs expressing LAG-3 found in advanced gastric cancer
Authors: Iwasawa Takumi , Yamauchi Suguru , Fukunaga Tetsu , Orita Hajime , Ito Tomoaki , Kazunori Kato 
Published: March 2024

Abstract
The development and progression of cancers are frequently promoted by immunosuppressive cells, such as Treg and myeloid-derived suppressor cells (MDSCs) mediated by various immune checkpoint molecules. Therefore, MDSCs are potential diagnostic and therapeutic targets in cancer. However, the definitive cell surface markers for defining MDSC and the subset that correlates with cancer progression are not clear. In our previous studies, there was no difference in the amount of total granulocyte MDSCs (G-MDSCs) between early and advanced gastric cancer. We inferred that there is a novel subset of G-MDSCs involved in cancer progression rather than the previous marker-based classification. The purpose of this study is to analyze MDSCs in gastric cancer patients at different stages of progression and to identify subsets of G-MDSCs that are involved in cancer progression. As a result, we identified a subset of novel G-MDSCs that correlate with cancer progression by expressing LAG-3. LAG-3 is a molecule that is expressed in Tregs and causes strong immunosuppression, suggesting that it is involved in the immunosuppressive potential of MDSCs.
Citation Format: Takumi Iwasawa, Suguru Yamauchi, Tetsu Fukunaga, Hajime Orita, Tomoaki Ito, Kato Kazunori. A novel subset of Treg-like MDSCs expressing LAG-3 found in advanced gastric cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5355.
Abstract 5356: Wild type Kirsten rat sarcoma (Kras) activation drives evasion of interferon-mediated immunity in hepatocellular carcinoma
Authors: Lei Mang Leng , Lee Terence Kin Wah 
Published: March 2024

Abstract
Background: Immune checkpoint inhibitors (ICIs) exhibit heterogeneous efficacy in patients with advanced hepatocellular carcinoma (HCC). Currently, there are no effective biomarkers to select patients who could benefit the most from ICIs or to predict response outcomes. Increasing evidence indicates that oncogenic pathway activation is associated with the generation of an unfavorable tumor microenvironment, with consequent immunotherapy resistance. Therefore, an understanding of the immune evasive mechanism of HCC is urgently needed.
Methods: Utilizing the antigen-expressing c-MycOE/Tp53KO HCC mouse model, a critical oncogenic signaling pathway in immune evasion was identified by data-independent acquisition mass spectrometry (DIA-MS) proteomics. Potential downstream pathways were investigated by scRNA-seq, immune profiling, western blot, and multiplexed immunofluorescence staining. We also examined the therapeutic potential of targeting wild-type Kras using the Kras inhibitor MRTX0902 and the MEK inhibitor trametinib to enhance the efficacy of immunotherapy in HCC.
Results: We identified a significant upregulation of wild-type Kras in immune-escaped tumors, with concurrent activation of its ligand-driven EGFR and its downstream MEK/ERK signaling. Likewise, endogenous Kras overexpression in this model resulted in increased tumor burden with reduced survival time in mice, implicating the regulatory role of Kras signaling in immune evasion. Clinically, wild-type Kras showed elevated expression in HCC at both the mRNA and protein levels, and was associated with tumor recurrence and poorer patient survival. Through scRNA-seq analysis, we demonstrated that Kras hindered dendritic cell recruitment, leading to compromised Cd8+ T cell activity via the suppression of interferon-mediated Cxcl9. Wild-type Kras activation further impaired HCC recognition by T cells via the downregulation of MHC-I expression. Notably, the combination therapy of MRTX0902, trametinib, and anti-PD-1 effectively enhanced intratumoral Cd8+ T cell infiltration and demonstrated a favorable response in survival outcomes.
Conclusion: This study showed that wild-type Kras, via the activation of its downstream MEK/ERK signaling, acts as a crucial immune evasive mechanism in HCC and contributes to resistance to anti-PD-1 therapy. It also provided new insights into the therapeutic potential of targeting wild-type Kras to enhance the efficacy of anti-PD-1 therapy, providing a foundation for further exploration and potential clinical applications in HCC.
Citation Format: Mang Leng Lei, Terence Kin Wah Lee. Wild type Kirsten rat sarcoma (Kras) activation drives evasion of interferon-mediated immunity in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5356.
Abstract 537: Preclinical PD-1 resistance models: Crucial tools for unveiling PD-1 resistance mechanisms and advancing novel treatment strategies
Authors: Zhu Yini , Fang Yuan , Wang Huiyi , Xing Jun , Yang Lu , Zhao Jing , Gao Xiang , Ju Cunxiang 
Published: March 2024

Abstract
In the cancer-immunity cycle, the immune checkpoint PD-1 and its ligand PD-L1 collaborate to facilitate tumor immune evasion and promote tumor progression by thwarting immunity-induced apoptosis. Immune checkpoint inhibitors disrupt this alliance by preventing PD-1 from binding to PD-L1, thereby reactivating the patient's immune system. While anti-PD-1/PD-L1 therapy has demonstrated remarkable efficacy in treating solid tumors, durable responses are observed in only a minority of patients. The majority of patients do not experience the full benefits of anti-PD-1/PD-L1 therapy, and a significant proportion of initial responders eventually develop acquired resistance. Thus, the establishment of reliable preclinical PD-1 resistance models is of paramount importance for uncovering resistance mechanisms and devising novel treatment strategies.
Common mechanisms contributing to PD-1/PD-L1 resistance include the absence of appropriate tumor antigens, inactivation of tumor surface MHC molecules, aberrant IFNγ signaling pathways, and the presence of an immunosuppressive tumor microenvironment. We have successfully generated multiple drug resistance models at both cellular and animal levels, offering valuable tools for the investigation of diverse drug resistance mechanisms. For instance, our animal model of drug resistance, induced by long-term treatment with the PD-1 antibody (Keytruda), simulates the clinical scenario of acquired resistance due to prolonged medication. Through gene editing techniques, we have created a drug-resistant cell line (CT26-B2M KO) by disrupting the B2M gene in the CT26 cell line, thereby mimicking a tumor model with B2M functional deficiency in mice. Additionally, we have compiled efficacy data from various naturally occurring resistant models, which serve as valuable resources for studying primary resistance or intricate resistance mechanisms.
In summary, preclinical PD-1 resistance models serve as crucial tools for researchers to dissect the intricacies of PD-1 resistance mechanisms and offer essential guidance for the development of innovative treatment strategies.
Citation Format: Yini Zhu, Yuan Fang, Huiyi Wang, Jun Xing, Lu Yang, Jing Zhao, Xiang Gao, Cunxiang Ju. Preclinical PD-1 resistance models: Crucial tools for unveiling PD-1 resistance mechanisms and advancing novel treatment strategies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 537.