bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5605: Ambient storage and stabilization of proteins and cell-free nucleic acids in whole blood samples
Authors: Li Jing , Bartron Lisa , LaRue Jordan , Mehta Sama , George Nicholas M.
Published: June 2023

Introduction: Highly anticipated advancements in biotechnology and instrumentation now allows for simultaneous detection of multiple biomarkers. This is accelerating the cancer research field towards the development of multianalyte-based in vitro diagnostic tests for early detection and/or monitoring of cancer. These multianalyte liquid biopsy tests are often based on detection of cancer-related proteins and/or tumor-specific genomic and transcriptomic changes (circulating cell-free nucleic acids) in plasma. A specialized and proprietary stabilization reagent has been developed for use in a blood collection tube with the capability to simultaneously stabilize protein biomarkers of interest and cell-free nucleic acids.

Methods: Blood samples from self-proclaimed healthy donors were drawn into evacuated blood collection tubes containing a new stabilization reagent and stored at room temperature. Plasma was isolated using a general double-spin protocol (1800 × g for 15 min and 2800 × g for 15 min) and frozen at -80 °C until use. Plasma levels of proteins of interest including cancer markers and immuno-oncology checkpoint markers were measured by Ella Simple Plex Assays (Bio-Techne) and Luminex xMAP® Technology Assays (Bio-Techne, samples tested by LuminexPLORE Lab). Total cell-free nucleic acids were isolated using the QIAamp Circulating Nucleic Acid Kit and the resultant cfDNA or cfRNA was analyzed with fluorometric-based assay (quantitative) and Bioanalyzer/Tapestation (qualitative).

Results: Compared with blood samples collected in EDTA and ACD-A tubes, the new stabilization reagent maintained the draw time levels of plasma proteins of interest such as TGF-β1, MMP-9, IL-8/CXCL8, CCL5/RANTES, Granzyme B, CEA and PD-L1 for up to 5 days of room temperature storage in whole blood. The reagent also effectively maintained draw time levels of plasma cell-free nucleic acids to near draw time levels. In addition, the new reagent also minimized in vitro hemolysis during room temperature storage.

Conclusion: This new and breakthrough stabilization reagent simultaneously maintains the draw time levels of proteins of interest and cell-free nucleic acids for an extended period of time in whole blood. It provides cancer researchers and clinical assay developers confidence in blood sample integrity and flexibility in sample storage, transport, and processing at ambient temperature for multianalyte analysis or multiomics profiling.

Citation Format: Jing Li, Lisa Bartron, Jordan LaRue, Sama Mehta, Nicholas M. George. Ambient storage and stabilization of proteins and cell-free nucleic acids in whole blood samples. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5605.
Abstract 5831: CD200R signaling contributes to unfavorable tumor microenvironment through regulating production of chemokines by tumor associated macrophages
Authors: Lin Cho-Hao , Talebian Fatemeh , Li Yang , Zhu Jianmin , Zhao Bolin , Liu Jin-Qing , Basu Sujit , Pan Xueling , Chen Xi , Yan Pearlly , Carson William E. , Xin Gang , Wen Haitao , Wang Ruoning , Li Zihai , Ma Qin , Bai Xue-Feng
Published: June 2023

CD200 is overexpressed in human solid tumors such as neuroblastoma and melanoma and is considered as an immune checkpoint molecule for dampening cancer immunity. However, how CD200 affects tumor microenvironment (TME) and host immunity is incompletely understood. In the present study, we evaluated the role of the CD200-CD200R pathway in TME using loss-of-function CD200R-/- mice, along with two clinically relevant, CD200-positive murine tumor models: the mouse neuroblastoma NB9464D and melanoma Yummer1.7. We found that comparing with the wild type mice, CD200R-/- mice were significantly more potent in rejecting these CD200+ tumors. Transcriptome analysis by single cell RNA sequencing demonstrated that tumors from CD200R-/- mice had more infiltration of CD45+ immune cells, including CD4+ and CD8+ T cells, and NK cells but less infiltration of neutrophils. Antibody depletion experiments revealed that immune effectors including CD8+ T cells and NK cells in combination, are crucial in inhibiting tumor growth in CD200R-/- mice. Mechanistically, we found that CD200R signaling differentially regulates the expression of chemokines in tumor-associated macrophages (TAMs). In the absence of CD200R, TAMs up-regulate CCL24 and CCL8 and down-regulate CXCL3, CXCL2, and CCL3 via activation of ERK and/or p38 MAP kinases. Increased expression of CCL24 in CD200R-deficient tumors resulted in increased infiltration of eosinophils, which also contributes to anti-tumor activity. Overall, we conclude that CD200R-mediated signaling, via interaction with CD200 on tumor cells, contributes to unfavorable TME primarily through chemokine-dependent recruitment of immune suppressive neutrophils and exclusion of anti-cancer immune effectors. Our study has significant implications in developing CD200-targeted immunotherapy of solid tumors.

Citation Format: Cho-Hao Lin, Fatemeh Talebian, Yang Li, Jianmin Zhu, Bolin Zhao, Jin-Qing Liu, Sujit Basu, Xueling Pan, Xi Chen, Pearlly Yan, William E. Carson, Gang Xin, Haitao Wen, Ruoning Wang, Zihai Li, Qin Ma, Xue-Feng Bai. CD200R signaling contributes to unfavorable tumor microenvironment through regulating production of chemokines by tumor associated macrophages [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5831.
Abstract 5832: Integrinα5 mediates the direct heterocellular interaction between cancer cells and cancer-associated fibroblasts and promotes peritoneal metastasis of diffuse-type gastric carcinoma
Authors: Yamaguchi Hideki , Miyamoto Shingo , Nagano Yoshiko , Miyazaki Makoto , Nagamura Yuko
Published: June 2023

Diffuse-type gastric carcinoma (DGC) is an aggressive subtype of gastric cancer characterized by rapid infiltrative growth and frequent peritoneal metastasis. Peritoneal metastasis is the main cause of poor prognosis and decreased quality of life for patients with DGC. Histologically, DGC tumor lesions are associated with massive fibrotic stroma caused by the extensive proliferation of cancer-associated fibroblasts (CAFs). Peritoneally metastasized tumors of DGC are also accompanied by abundant fibrotic stroma and CAFs. CAFs are known to promote the progression of DGC by enhancing the growth, invasion, and dissemination of tumor cells. Previously, we reported that the direct heterocellular interaction between cancer cells and CAFs is necessary for the invasion and peritoneal metastasis of DGC. In this study, we aimed to identify and target the molecules that mediate such direct heterocellular interaction. Monoclonal antibodies (mAbs) against intact DGC cells were generated and subjected to high-throughput screening to obtain mAbs that block the adhesion of DGC cells to CAFs. As a result, several such inhibitory mAbs were obtained. Immunoprecipitation and mass spectrometry revealed that all mAbs recognized integrin α5 complexed with integrin β1. Blocking integrin α5 in DGC cells abrogated the adhesion of DGC cells to CAFs. Similarly, blocking fibronectin, a ligand of integrin α5β1, deposited on CAFs blocked the heterocellular adhesion. Furthermore, administration of mAbs or knockout of integrin α5 in DGC cells suppressed their invasion led by CAFs in vitro and peritoneal metastasis in a mouse xenograft model. Analysis of the public database revealed that integrin α5 and fibronectin were highly expressed in DGC. In addition, integrin α5 and fibronectin expression levels were correlated with worse overall survival in DGC patients. Taken together, these results show that integrin α5 mediates the heterotypic cancer cell-CAF interaction during peritoneal metastasis of DGC and may thus be a promising therapeutic target.

Citation Format: Hideki Yamaguchi, Shingo Miyamoto, Yoshiko Nagano, Makoto Miyazaki, Yuko Nagamura. Integrinα5 mediates the direct heterocellular interaction between cancer cells and cancer-associated fibroblasts and promotes peritoneal metastasis of diffuse-type gastric carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5832.
Abstract 6240: The potent quadruplex-binding compound QN-302 shows anti-tumor activity as a monotherapy in an orthotopic in vivo model of pancreatic cancer
Authors: Williams Nicole , Santos Danielle , Worthington Jenny , Ahmed Ahmed , Arshad Tariq , Neidle Stephen
Published: June 2023

The compound QN-302, a tetra-substituted naphthalene diimide derivative has single-digit nM anti-proliferative activity in a panel of human pancreatic cancer (PDAC) cell lines (Ahmed et al., ACS Med Chem Lett, 2020, 11, 1634-1644). It has significant anti-tumor activity in the MIA-PACA2 xenograft model for PDAC and in the genetic KPC model. We now report that this compound also shows significant mono-therapy anti-tumor activity in an orthotopic model for PDAC. Female athymic nude mice bearing orthotopically implanted pancreatic BxPC-3 cells were dosed with 1 x weekly IV QN-302 at 0.5 and 1.0 mg/kg, over a period of 21 days. A separate group of mice was treated with Gemcitabine twice weekly IV during this period, at a dosage of 15 mg/kg. Blood samples from animals were collected on a weekly basis and were used to detect and quantify circulating tumor DNA as a method of following treatment efficacy. In line with previous studies QN-302 was well-tolerated at 0.5 and 1.0 mg/kg with no adverse effects on animal health or behavior noted during the study. Circulating tumor DNA levels were significantly less than vehicle controls in gemcitabine-treated animals from day 7 and QN-302 (1.0 mg/kg) treated animals from day 14 of treatment. Survival was significantly increased in gemcitabine and QN-302 (1.0 mg/kg) QW treatment groups. Statistically significant efficacy was observed in gemcitabine and QN-302 (1.0 mg/kg) treated animals. Examination of blood chemistry and biochemistry of treated animals did not indicate any adverse effects due to QN-302. This orthotopic model is the 4th in vivo study in a pancreatic cancer model showing anti-tumor activity for QN-302, further confirming the potential of this compound for human disease. QN-302 is currently in an advanced stage of pre-IND development by Qualigen Inc.

Citation Format: Nicole Williams, Danielle Santos, Jenny Worthington, Ahmed Ahmed, Tariq Arshad, Stephen Neidle. The potent quadruplex-binding compound QN-302 shows anti-tumor activity as a monotherapy in an orthotopic in vivo model of pancreatic cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6240.
Abstract 6287: Selective CBP degradation shows superior potency and differentiated biological activity compared to small molecule inhibitors
Authors: La Bonte Laura , Sappal Darshan
Published: June 2023

CREB binding protein (CBP) and E1A binding protein (p300) are paralog histone acetyltransferases involved in many cellular processes via their activity as transcription factor co-activators. Dysregulation of one or both proteins has been implicated in a variety of cancers, and functional genomic screens have exhibited a bidirectional synthetic lethal relationship between the two genes in many cancer indications. Due to the high homology between CBP and p300, identification of selective chemical matter that specifically and directly targets CBP has proven challenging. Small molecule inhibitors (SMIs) targeting the HAT or bromodomain of CBP/p300 have been developed, however these agents are not selective for either paralog and inhibit both proteins equally, potentially limiting their clinical application. Herein, we describe the biological activity of selective, potent CBP degraders and show differentiation from SMIs.

Citation Format: Laura La Bonte, Darshan Sappal. Selective CBP degradation shows superior potency and differentiated biological activity compared to small molecule inhibitors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6287.
Abstract 6289: Enhancer reprogramming by novel SMARCA2 degrading PROTACs underlies therapeutic utility in SMARCA4 mutant tumors
Authors: Kotagiri Sasi , Blazanin Nicholas , Xi Yuanxin , Wang Jing , Lissanu Yonathan
Published: June 2023

Lung cancer is the top cause of cancer mortality. Despite recent advances, the majority of patients with lung cancer still lack effective therapeutic options, underscoring the dire need for additional treatment approaches. Genomic studies have identified frequent mutations in subunits of the SWI/SNF chromatin remodeling complex including SMARCA4 and ARID1A in non-small cell lung cancer with a frequency of up to 33% in advanced stage disease, making it the most frequently mutated complex in lung cancer. Recent reports, as well as our own data, have identified the paralogue SMARCA2 to be synthetic lethal to SMARCA4 suggesting SMARCA2 is a valuable therapeutic target. However, the discovery of selective inhibitors of SMARCA2 has been challenging. To overcome this hurdle, we have utilized iterative structure-activity relationship (SAR) studies to develop novel, potent and selective SMARCA2 degrading small molecules based on proteolysis targeting chimera (PROTAC) technology. We demonstrated that YD23, our lead SMARCA2 PROTAC, potently and selectively induces degradation of SMARCA2. Mechanistically, we demonstrated that YD23 reduces chromatin accessibility only in SMARCA4-deficient cells with profoundly decreased chromatin accessibility at enhancer regions. Gene expression profiling and pathway analysis indicated that core cell cycle genes were downregulated by YD23 and is consistent with reduced chromatin accessibility at their regulatory regions. Furthermore, integrative analysis of RNA-seq and ATAC-seq revealed a strong correlation between gene expression and enhancer accessibility changes by YD23. In particular, we identified the mitotic regulator NEDD9 as a critical target in enhancers that are strongly reduced by YD23 in SMARCA4-deficient lung cancer cells. In conclusion, our study provides a promising chemical probe for studying the synthetic lethal interaction between SMARCA2 and SMARCA4, dissect the chromatin and epigenetic landscape alterations and lay the foundation for future preclinical and clinical development of SMARCA2 degraders as therapeutics.

Citation Format: Sasi Kotagiri, Nicholas Blazanin, Yuanxin Xi, Jing Wang, Yonathan Lissanu. Enhancer reprogramming by novel SMARCA2 degrading PROTACs underlies therapeutic utility in SMARCA4 mutant tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6289.
Abstract 629: Characterization of the molecular mechanism of APOC1 in anti-ferroptosis and lymph node microenvironment remodeling in ESCC metastasis process
Authors: Liu Beilei , Zhang Baifeng , Zhou Hongyu , Tan Licheng , Fang Xiaona , Gong Lanqi , Luo Jie , Huang Jinlin , Huang Jiao , Yang Yuma , Guan Xinyuan
Published: June 2023

The invasion and metastasis affect the survival and prognosis of patients with esophageal carcinoma (ESCC). Through single-cell sequencing analysis of para-cancerous tissue, tumor tissue, normal lymph node tissue and lymph node metastasis tissue in 4 untreated ESCC patients, we found that APOC1 was specifically up-regulated in lymph node metastasis tissue and tumor tissue. In vitro and in vivo experiments revealed that APOC1 overexpression significantly promoted the migration and anti-ferroptosis function in ESCC. Also, APOC1 upregulation promotes M2 macrophage differentiation, Treg aggregation, and CD8 T cell immune inactivation in lymph node metastasis tissue. Mechanistically, APOC1 competes with NRF2 to bind Keap1, promoting nuclear translocation of NRF2 thus upregulating activation of the NRF2 pathway in tumor cells. For the lymph node metastasis tumor microenvironment, secreted APOC1 could upregulate the oxLDL which induced M2 macrophage polarization via CD36/JAK2/STAT3 axis. Overall, in this study, we explored the role and molecular mechanism of APOC1 in ESCC metastasis process which could provide a new molecular therapeutic approach to ESCC patients.

Citation Format: Beilei Liu, Baifeng Zhang, Hongyu Zhou, Licheng Tan, Xiaona Fang, Lanqi Gong, Jie Luo, Jinlin Huang, Jiao Huang, Yuma Yang, Xinyuan Guan. Characterization of the molecular mechanism of APOC1 in anti-ferroptosis and lymph node microenvironment remodeling in ESCC metastasis process [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 629.
Abstract 632: Exploiting pyroptosis in melanoma brain metastasis
Authors: Cavallo Maria R.
Published: June 2023

Melanoma is the deadliest form of skin cancer due to its frequent metastasis to the brain. Melanoma brain metastases (MBM) are a significant clinical challenge, and current model systems and therapeutic strategies are poor. Inhibitors targeting the most common oncogenic driver of melanoma, BRAFV600E (BRAFi), disrupt mitogenic signaling and promote caspase-3 associated cell death. Though caspase-3 is a well-known apoptotic driver, it can also cleave Gasdermin E (GSDME) to create pore-forming N-terminal fragments that oligomerize at plasma and mitochondrial membranes and trigger pyroptosis - a form of immunogenic cell death (ICD). Our recent work illustrates the importance of GSDME mediated pyroptosis and associated immunogenicity in providing a durable therapeutic response against melanoma. Since pyroptosis can be activated by GSDME cleavage via caspase-3, and is prominent in various neuropathologies, a better understanding of the interplay between central nervous system (CNS) immune cells and BRAFi-mediated ICD is critical for designing more effective therapies against MBM. Here, we engineered a panel of inducible pyroptotic melanoma cells to model BRAFi-mediated pyroptosis. Using ex vivo CNS slice co-cultures, we found that inducible N-GSDME expression in human and murine melanoma cells drives propidium iodide uptake and release of inflammatory activators like HMGB1 and IL-1 - hallmarks of pyroptosis. Importantly, conditioned media from these pyroptotic cells stimulates a more robust phagocytic response from resident macrophages of the CNS and pyroptotic melanoma elicit stronger cytotoxicity from syngeneic CD8+ T cells, further highlighting the benefits of BRAFi-mediated ICD. Our findings provide evidence that resident CNS immune cells and peripheral T cells respond to pyroptotic melanoma, suggesting that induction of ICD should be a consideration in the development of anti-MBM therapies.

Citation Format: Maria R. Cavallo. Exploiting pyroptosis in melanoma brain metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 632.
Abstract 6320: CUSP06/AMT-707, a new CDH6-targeting antibody-drug conjugate, demonstrates potent antitumor activity in preclinical models
Authors: Lu Wei , Shi Jing , Liu Shu-Hui , Covino Nicole , Meng Xun , Slosberg Eric D.
Published: June 2023

Cadherin-6 (CDH6), also known as K-cadherin, is a type II classic cadherin molecule that plays an important role in the embryonic development of the kidney, but has very limited expression in adult tissues. It is overexpressed in several human malignancies, primarily in ovarian, renal, but also (to a lesser degree) gastric, thyroid, cholangiocarcinoma and other tumor types. The characteristics of limited expression in normal tissues, high expression in tumor tissues, and rapid internalization upon antibody binding makes CDH6 a well-suited Antibody-drug Conjugate (ADC) target. We developed a novel CDH6-targeting ADC, CUSP06, consisting of a proprietary humanized antibody selective for CDH6, a protease cleavable linker, and an exatecan payload, with a drug-to-antibody ratio (DAR) of 8. CUSP06 selectively bound to cell surface CDH6 and was efficiently internalized into CDH6 positive ovarian and renal cancer cells. CUSP06 exhibited strong antiproliferative activity against several CDH6 positive cancer cell lines in vitro. Furthermore, compared to a DXd-based ADC, a exatecan-based ADC demonstrated improved bystander effect. Treatment with CUSP06 resulted in tumor regression in several CDH6 positive cell line derived xenograft (CDX) models, including PA-1, OVCAR3, and 786-O. In addition, CUSP06 demonstrated potent antitumor activity with tumor regression observed in two CDH6 low and high expressing patient derived xenograft (PDX) models. The preclinical activity of CUSP06 against CDH6-expressing tumors provide compelling support for the clinical development of CUSP06 in CDH6-expressing human cancers. CUSP06 is currently in IND-enabling studies. CUSP06 showed an expected toxicity profile consistent with it's exatecan payload in the ongoing pilot toxicology studies. We plan to initiate a Phase 1 first-in-human clinical trial in the 2nd half of 2023.

Citation Format: Wei Lu, Jing Shi, Shu-Hui Liu, Nicole Covino, Xun Meng, Eric D. Slosberg. CUSP06/AMT-707, a new CDH6-targeting antibody-drug conjugate, demonstrates potent antitumor activity in preclinical models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6320.
Abstract 6327: Intratumoral administration of ultra high-concentration nitric oxide (UNO) is more efficacious than anti-PD1 therapy in 4T1 tumor-bearing mice
Authors: Epshtein Yana , Goldshtein Matan , Chaisson Selena , Monson Jedidiah , Johnson Matt , Avniel Amir , Lisi Steve , Confino Hila
Published: June 2023

Background: For the majority of metastatic triple-negative breast cancer (mTNBC) patients, chemotherapy is the standard first-line treatment, however, outcomes in this population are poor. A monoclonal antibody against the immune checkpoint inhibitor anti-programmed death 1 (PD-1) also has antitumor activity in patients with mTNBC. Previously, we reported that delivering ultra-high concentrations of nitric oxide (UNO) to mouse colon tumors stimulated innate and adaptive immune responses leading to the rejection of secondarily-induced tumors. Moreover, adding an anti-PD-1 antibody to UNO treatment resulted in primary tumor regression in 53% of the mice, the rejection of a distant tumors in all mice, and prolonged survival compared to control and anti-PD-1 arms. In this in vivo study, we investigated the ability of UNO to improve the efficacy of anti-PD-1 antibody treatment in the aggressive mouse breast cancer model, 4T1.

Methods: We tested two treatment protocols: 4T1 mice tumors were treated with either a single dose of UNO and anti-PD-1 or a repeated dose of UNO and anti-PD-1. In the single dose design, 4T1 tumors were treated with a single administration of UNO combined with Anti-PD1 administration starting one day after UNO treatment (n=9-10 mice per group). In the repeated dosing design, 4T1 tumors were treated with UNO twice combined with Anti-PD-1 administration starting on the first UNO treatment day (n=8 mice per group). • UNO treatment regimen: 50,000 ppm, 10 minutes, flow rate ~0.2 liters per minute • Anti-PD1 treatment regimen: 10 mg/kg antibody was administered every 3 days for a total of 5 treatments.

Results (UNO Single Dose): The primary tumors of 4T1 tumor-bearing mice were 13.2% smaller in the combined single-dose UNO group compared to anti-PD-1 alone 15 days post-UNO treatment.

Results (UNO Repeated Dosing): The primary tumors of 4T1 tumor-bearing mice were 25.2% smaller in the combined repeated dose UNO group compared to the anti-PD-1 alone group 16 days after the first UNO treatment.

Conclusion: Treating 4T1 tumors with single and repeated doses of UNO improved outcomes compared to anti-PD-1 alone. This suggests that local short-term treatment with UNO can serve as a treatment option for cancer patients with tumors that are not amenable to immune checkpoint inhibitor treatment.

Citation Format: Yana Epshtein, Matan Goldshtein, Selena Chaisson, Jedidiah Monson, Matt Johnson, Amir Avniel, Steve Lisi, Hila Confino. Intratumoral administration of ultra high-concentration nitric oxide (UNO) is more efficacious than anti-PD1 therapy in 4T1 tumor-bearing mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6327.
Abstract 6328: An off-the-shelf Twin BiTE combination therapy controls heterogenous glioblastoma and shapes immune response
Authors: Rossignoli Filippo , Borges Paulo , Lumia Rebecca , Shah Khalid
Published: June 2023

Glioblastoma (GBM) is the most common primary brain tumor in adults, characterized by a median survival of 12-14 months with less than 10% of patients surviving at least 2 years from diagnosis. The discovery of tumor-associated antigens (TAAs) has permitted development of a new array of therapeutic strategies that selectively target GBM and spare normal cells of the CNS. In this study we used an alternative off-the-shelf approach to activate the immune system and direct it against the tumor, taking into account antigen heterogeneity and TME immune suppression without the need of engineering the patient’s immune cells. We generated TAA-targeting Bispecific T-cell Engagers (BiTEs) and engineered adult stem cells to secrete twin BiTEs (T-BiTE-SC). The approach was tested in combination with in naïve T cells on established and primary patient-derived cell lines expressing various levels of the target antigens. Moreover, to further support the therapeutic action of T cells, and combat immune-suppressive microenvironment and exhaustion, we combined our T-BiTE SC with an immune-stimulating cytokine. We show the efficacy of the individual BiTEs against different primary and established tumor cell lines. Moreover, the T-BiTE-SC, significantly controlled the growth of a tumor expressing heterogeneous levels of the targeted antigens. The immune stimulation reduced T cell exhaustion and consolidated a Th1 phenotype. Altogether our study demonstrated the feasibility and efficacy of an off-the-shelf immunotherapy, based on BiTEs simultaneously targeting tumor heterogeneity without the need for direct engineering of the immune cells.

Citation Format: Filippo Rossignoli, Paulo Borges, Rebecca Lumia, Khalid Shah. An off-the-shelf Twin BiTE combination therapy controls heterogenous glioblastoma and shapes immune response [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6328.
Abstract 6333: Repurposing NSAIDs for chemo-immunotherapy: mechanisms beyond COX inhibition
Authors: Okoko Ogacheko D. , Gazi Md Y. , Wang Xin , Brandle Caitlin , Kehinde-Ige Mercy , Piazza Gary A. , Shi Huidong , Zhou Gang
Published: June 2023

It has been well-established that some nonsteroidal anti-inflammatory drugs (NSAIDs) have antitumor activities. The beneficial effects of these NSAIDs are mainly attributed to their ability to inhibit the production and activity of cyclooxygenases (COX1 and COX2) and prostaglandin (PGE2), which are known to promote tumor progression, angiogenesis, metastasis and immunosuppression. We recently reported that administration of indomethacin, a prototypical NSAID, can enhance the antitumor efficacy of adoptive T cell therapy in animal models. However, currently adoptive T cell therapy as a treatment option is only suitable for selected patients with certain types of cancer. Here, we set out to explore the utility of indomethacin in a chemo-immunotherapy setting that is readily applicable to a wide range of cancers. Cyclophosphamide (CTX) is a widely used antineoplastic chemotherapeutic agent with immunostimulatory activities when used at low-medium doses. We show that indomethacin had no impact on tumor growth but can significantly enhance the antitumor effect of CTX in multiple mouse tumor models. The beneficial effect of indomethacin was diminished in immunodeficient mice or CD8 T cell-depleted wild-type mice, indicating the requirement for the host immunity. Furthermore, the CTX and indomethacin regimen can sensitize tumors to anti-PD1 immunotherapy. scRNAseq analysis of tumor samples revealed the impact of indomethacin on the tumor microenvironment. Our data also indicate that the immunopotentiating effect of indomethacin can be independent of PGE2 inhibition, and involves the TRAIL-DR5 axis in promoting tumor regression. Other potential mechanisms, including modulation of chronic interferon signaling in tumor cells, have also been investigated. Altogether, our study sheds light on the multiple mechanisms underlying indomethacin’s beneficial effects, and highlights the potential of NSAID administration as a readily applicable and cost-effective approach to augment the efficacy of chemo-immunotherapy.

Citation Format: Ogacheko D. Okoko, Md Y. Gazi, Xin Wang, Caitlin Brandle, Mercy Kehinde-Ige, Gary A. Piazza, Huidong Shi, Gang Zhou. Repurposing NSAIDs for chemo-immunotherapy: mechanisms beyond COX inhibition [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6333.
Abstract 6341: Preclinical development of a monoclonal antibody targeting CD70 as cancer immunotherapy
Authors: Tian Wenzhi , Li Song , Chen Dianze , Liu Dandan , Guo Huiqin , Yang Chunmei , Zhang Li , Zhang Wei , Tu Xiaoping , Peng Liang , Zhao Gui , Zhang Ruliang , Zhang Fan , Gan Frank X.
Published: June 2023

CD70 is a novel immune checkpoint highly expressed on cancers of kidney, blood and lymphoid tissues, mesothelium and gastrointestinal system. High expression of CD70 is a prognostic marker for poor survival in patients with ovarian carcinoma, pancreatic cancer and mesothelioma, etc. Several CD70 antibodies are under early stages of clinical trials for oncology indications. We have developed IMM40H, a humanized IgG1 antibody that differentially induces phagocytosis and cytotoxicity in CD70-expressing cancer cells. Results of in vitro study have demonstrated that, in comparison with cusatuzumab, IMM40H possesses better CD70 binding (kD= 3.22E-11M) and functional inhibition ability, as well as more potent activities of ADCC (antibody-dependent cellular cytotoxicity, EC50 = 0.5 -2.0ng/ml) and CDC (complement-dependent cytotoxicity, EC50 = 170 ng/mL) against certain cancer cells. IMM40H also induces strong ADCP (antibody-dependent cellular phagocytosis) activity (EC50 = 0.02nM). At doses between 0.3 mg/kg to 10mg/kg, IMM40H significantly reduced tumor volume in mouse models of multiple myeloma, lymphoma and kidney cancer. Notably, in a U266 multiple myeloma model, IMM40H, at the dose of 0.3 mg/kg, completely inhibited tumor growth in a way that therapeutic effects appeared significantly earlier than that of cusatuzumab at a higher dose of 1 mg/kg. Therapeutic effects of IMM40H at the dose of 3 mg/kg also appeared earlier than that of bortezomib at the dose of 0.5 mg/kg. Interestingly, combination of IMM40H and IMM01 (a SIRPα-IgG1 Fc fusion protein targeting CD47) generated significant therapeutic synergy in models of A498 kidney cancer and Raji lymphoma. Importantly, maximum tolerated dose of IMM40H exceeds 100 mg/kg (IV, single dose) in cynomolgus monkeys and no significant adverse reaction was observed at a dose range of 3 to 30 mg/kg (IV, QW, 5 times) in monkeys. Taken together, our data show that targeting CD70 on tumor cells using IMM40H antibody may serve as a potent immunotherapy for multiple cancer indications. IND of IMM40H has been approved in China and US. This antibody is now in a phase 1 study in patients with advanced malignancies expressing CD70.

Citation Format: Wenzhi Tian, Song Li, Dianze Chen, Dandan Liu, Huiqin Guo, Chunmei Yang, Li Zhang, Wei Zhang, Xiaoping Tu, Liang Peng, Gui Zhao, Ruliang Zhang, Fan Zhang, Frank X. Gan. Preclinical development of a monoclonal antibody targeting CD70 as cancer immunotherapy. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6341.
Abstract 6343: 7E1, a novel blocking antibody targeting human anti-Müllerian-hormone-receptor II (AMHRII), elicits potent anti-tumor activity in vivo
Authors: Yang Yongfei , Li Huilin , Li Hao , Yan Yue , Li Jianhui , Lin Qingcong , Yin Huijun , Zhou Xiangshan , Zhang Miao , Wu Kunbao , Sun Leqiao , Zhong Shan
Published: June 2023

Anti-Müllerian hormone (AMH), is a TGF-β family autocrine hormone and cognate ligand for the type II AMH receptor (AMHR2). AMH signaling through AMHR2 plays an important role in fetal sexual development by inducing Müllerian duct regression in males. AMHR2 is aberrantly expressed in various human malignancies, including colon, testis, gastric, and ovarian cancers. Functionally, AMH has complex effects on cell cycle regulation; at physiological concentrations it promotes survival and chemoresistance of cell lines, whereas at supraphysiological concentrations it inhibits tumor cell viability. Like other TGF-β family members, binding of its target receptor effects changes in gene expression through activation of intracellular SMAD, NF-κB, and Akt signaling. We developed a fully human anti-AMHR2 monoclonal antibody, 7E1, from RenMab™ mice, which contain the full human immunoglobulin variable domain. 7E1 was found to contain a distinct binding epitope associated with efficient inhibition of AMH binding and signaling. 7E1 also displayed a better ADCC effect than the reference AMHR2 antibody. The in vivo half-life of 7E1 in AMHR2- and FcRn-humanized mice exceeded the reference antibody as well and is in a desirable range from a development perspective. To evaluate the safety and efficacy of 7E1 in vivo, we established syngeneic murine tumor models in AMHR2-humanized mice. We found that 7E1 monotherapy significantly inhibited tumor growth in a dose-dependent manner. Moreover, 7E1 was well tolerated in mice, and no adverse effects were observed even at extremely high doses (e.g. 100 mg/kg). Taken together, these data demonstrate that 7E1 is a novel anti-human AMHR2 blocking antibody with desirable pharmacokinetic and pharmacodynamic properties. 7E1 may potentially find broad application for a range of cancer indications in which AMH signaling is implicated.

Citation Format: Yongfei Yang, Huilin Li, Hao Li, Yue Yan, Jianhui Li, Qingcong Lin, Huijun Yin, Xiangshan Zhou, Miao Zhang, Kunbao Wu, Leqiao Sun, Shan Zhong. 7E1, a novel blocking antibody targeting human anti-Müllerian-hormone-receptor II (AMHRII), elicits potent anti-tumor activity in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6343.
Abstract 6351: Reversal of dysfunctional CIK cells after the exposure to resistant cholangiocarcinoma cells through chemical perturbation of resistant gene signature
Authors: Wongkajornsilp Adisak , Htwe Khin Su Su , Chusorn Porncheera , Duangsa-ard Sunisa , Kasetsinsombat Kanda , Sawatpiboon Nathawadee
Published: June 2023

Clinical trials on cholangiocarcinoma revealed differential sensitivity to cytolytic action of allogeneic cytokine-induced killer (CIK) cells. Different metastatic foci in the same individual could also display different sensitivity. The differential sensitivity of separate lines of cultured cholangiocarcinoma cells could be demonstrated based on the evaluation of GR50. Allogeneic CIK cell or CD3+CD56+ subset was co-cultured with nine cell lines at E:T ratio of 20:1 for 48 h. The tumor cells were categorized into 2 groups based on the obtained GR50. This resulted in 4 sensitive cell lines and 5 resistant cell lines. The cholangiocarcinoma cell-exposed CIK cell and CD3+CD56+ subset displayed defective anti-tumor cytotoxicity upon subsequent experiment. RNAseq analysis revealed 261 genes upregulated in sensitive cell lines and 665 genes upregulated in resistant cell lines. The top 50 resistant genes were evaluated for their linked signal transduction and protein interaction network. Based on the interaction network, a list of chemicals that could interrupt the stipulated network were selected. They were assayed for their synergistic activity with dysfunctional CIK cell or CD3+CD56+ subset for cytolysis of resistant tumor cells.

Citation Format: Adisak Wongkajornsilp, Khin Su Su Htwe, Porncheera Chusorn, Sunisa Duangsa-ard, Kanda Kasetsinsombat, Nathawadee Sawatpiboon. Reversal of dysfunctional CIK cells after the exposure to resistant cholangiocarcinoma cells through chemical perturbation of resistant gene signature [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6351.
Abstract 6359: Structural insights into Siglec-15 reveal glycosylation dependency for interaction with T cells through integrin CD11b
Authors: Lenza Maria Pia , Egia-Mendikute Leire , Antoñana-Vildosola Asier , Soares Cátia O. , Corzana Francisco , Oyenarte Iker , Marcelo Filipa , Jiménez-Barbero Jesús , Ereño-Orbea June , Palazon Asis
Published: June 2023

Sialic acid-binding Ig-like lectin 15 (Siglec-15) is emerging as an immune modulator and target for cancer immunotherapy. However, limited knowledge regarding the mechanism of action, structure and binding partners on T cells restrains the development of drug candidates that unleash its full therapeutic potential. Here, we solve the crystal structure of Siglec-15 and delineate its binding epitope by co-crystallization with an anti-Siglec-15 blocking antibody. Saturation transfer-difference (STD) nuclear magnetic resonance (NMR) spectroscopy assisted with molecular dynamic simulations revealed the binding mode of Siglec-15 to the cancer-associated sialyl-Tn (sTn) glycoform. Binding of Siglec-15 to T cells, which lack sTn expression, depends on the presence of sialic acid. We identified the leukocyte integrin CD11b as a binding partner of Siglec-15 on human T cells. Collectively, these data provide an integrative understanding of the structural features of Siglec-15 and underscore glycosylation as an additional layer of control of T cell responses.

Citation Format: Maria Pia Lenza, Leire Egia-Mendikute, Asier Antoñana-Vildosola, Cátia O. Soares, Francisco Corzana, Iker Oyenarte, Filipa Marcelo, Jesús Jiménez-Barbero, June Ereño-Orbea, Asis Palazon. Structural insights into Siglec-15 reveal glycosylation dependency for interaction with T cells through integrin CD11b [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6359.
Abstract 6428: Targeting SMARCAL1 as a therapeutic strategy to enhance cGAS/STING signaling in gastric cancer
Authors: Hsu Po-Yen , Chuang Yu-Ming , LIN Shu-Hui , Lee Yu-Ting , Chen Yin-Chen , Ng Enders K.W. , YEH Kun-Tu , Cheng Alfred S.L. , Chan Michael W.Y.
Published: June 2023

Gastric cancer is one of the leading causes of cancer death in Eastern Asia. Although immunotherapy, such as immune checkpoint blockade, is an emerging therapeutic strategy against gastric cancer, only a fraction of cancer patients show a therapeutic response. Therefore, developing a novel therapeutic strategy to turn a “cold” tumor into a “hot” tumor is considered a crucial issue in cancer treatment. By methylomic analysis, we found that SMARCAL1 is one of the STAT3 targets which might be regulated by STAT3-mediated promoter methylation. Moreover, an inverse correlation between SMARCAL1 promoter methylation and expression was observed in the TCGA online database and in our cell lines experiment. Bisulfite pyrosequencing also showed a significant hypomethylation of SMARCAL1 compared to gastritis and adjacent normal in our in-house cohort (gastritis n=15; IM n=13; cancer n=58). More importantly, SMARCAL1 knockdown showed increased sensitivity of gastric cancer cell lines to DNA-damaging agents and increase the expression of cGAS and its downstream target, IFNB1. Therefore, in this study, we propose SMARCAL1 as a therapeutic target for improving the efficiency of immunotherapy by enhancing the cGAS/STING signaling pathway.

Citation Format: Po-Yen Hsu, Yu-Ming Chuang, Shu-Hui LIN, Yu-Ting Lee, Yin-Chen Chen, Enders K.W. Ng, Kun-Tu YEH, Alfred S.L. Cheng, Michael W.Y. Chan. Targeting SMARCAL1 as a therapeutic strategy to enhance cGAS/STING signaling in gastric cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6428.
Abstract 6435: BCG008, a human Siglec-15 blocking antibody, displays potent anti-tumor activity in Siglec-15-humanized mice
Authors: Yang Yongfei , Qu Aidong , Yao Fengping , Song Pan , Liang Hongyuan , Tian Maopeng , Yang Fang , Yu Zhaoxue , Zhou Xu , Li Xiuling
Published: June 2023

Sialic acid-binding Ig-like lectin 15, or Siglec-15, is identified as a critical immune suppressor. Siglec-15 expression is normally limited to certain myeloid cells, but it can be upregulated in a variety of tumors and on tumor-infiltrating myeloid cells. Siglec-15 significantly inhibits antigen-specific T cell responses both in vitro and in vivo. Conversely, genetic ablation of Siglec-15 promotes anti-tumor responses. Therefore, a Siglec-15-targeting blocking antibody could represent a novel class of anti-tumor immunotherapy. BCG008, a fully human monoclonal antibody antagonist of Siglec-15, was generated from RenMab™ mice, which contain the entire human immunoglobulin variable domain. Compared to a reference Siglec-15 blocking antibody (5G12), BCG008 exhibited higher affinity for human and cynomolgus monkey Siglec-15 and targeted distinct binding epitopes. In in vitro studies, BCG008 significantly abrogated Siglec-15-mediated T cell suppression in a dose-dependent manner, as measured by CD4+ and CD8+ T cell proliferation. Subsequently, the efficacy and safety of BCG008 was evaluated in syngeneic tumor models in Siglec15-humanized mice. BCG008 monotherapy significantly inhibited tumor growth, and the effect of the tumor inhibition was potentiated when administered in combination with other immune-checkpoint inhibitors, including anti-PD-L1 antibodies. In safety evaluation, BCG008 was well-tolerated in the tumor-bearing mice; no adverse effects were observed even at high doses (e.g. 30 mg/kg). Taken together, these results demonstrate that BCG008 is a novel anti-human Siglec-15 blocking antibody with favorable efficacy and safety profiles that can provide potential benefits for future cancer immunotherapy.

Citation Format: Yongfei Yang, Aidong Qu, Fengping Yao, Pan Song, Hongyuan Liang, Maopeng Tian, Fang Yang, Zhaoxue Yu, Xu Zhou, Xiuling Li. BCG008, a human Siglec-15 blocking antibody, displays potent anti-tumor activity in Siglec-15-humanized mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6435.
Abstract 6438: Next-generation pan-cancer immunotherapy with patient-derived APC
Authors: Bian Zhen , Shi Lei , Liu Yuan , Stylli harry
Published: June 2023

Harnessing phagocytic antigen presenting cells (APC) and tumor neoantigen-specific T cells represent the ultimate power of immunotherapy against cancer. The promises of phagocytic APCs lie in their abilities of not only initiating phagocytosis towards cancer cells (to “eat off” tumor) but also, through immunogenic antigen presentation, activating neoantigen-specific Tcells that systemically and durably eliminate cancer cells, as well as the establishment of a long-lasting cellular and hormonal immunity that prevents tumor recurrence. However, the efforts of developing APCs -based therapy have been hindered by the current lack of technology that robustly produce APCs from cancer patients, as none of the traditional methods for differentiating DC or macrophage APCs are effective for cancer patients.

Through a proprietary process, we have created a unique reagent combo that enables robust differentiation of cancer patients’ peripheral monocytes (cMo) to be potent APC, termed κAPC. κAPC display a unique gene expression profile, separating from classical DC or macrophage, and profound proinflammatory phenotype with enhanced phagocytic capability and elevated immunogenic antigen presentation machinery. In both in vitro and in vivo settings, κAPC demonstrate direct uptake of tumor antigens and presentation to T cells, the latter leading to activation and large expansion of multi-targeting, polyclonal tumor-specific CD4 and CD8 T populations - termed NeoT- from circulating and tumor-infiltrating lymphocytes. Theexpanded CD8 NeoT are highly tumoricidal and once adoptively transferred in vivo, potently eliminated late-stage metastatic solid tumors, whereas CD4 NeoT contribute to immune memory and repolarize a proinflammatory TME favorable for tumor elimination.

Key words: κAPC, NeoT, NeoT adoptive cell therapy, κAPC-based cancer vaccine, combination therapies

Citation Format: Zhen Bian, Lei Shi, Yuan Liu, harry Stylli. Next-generation pan-cancer immunotherapy with patient-derived APC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6438.