tbuckley/cabot-search huggingface dataset:
Abstract 5476: In vitro real-time evaluation of bystander effects of antibody-drug conjugates
Authors: Xiaoyu Zhang, Yun-fei Pu, Tian Wang, Grace Yang, Peifang Ye, Nancy Li
Journal: Cancer Research (2025)

Abstract Antibody-drug conjugates (ADCs) represent a pivotal advancement in biotherapy, leveraging targeted internalization to treat tumors effectively. A critical phenomenon associated with ADCs is the bystander effect, where cytotoxic drugs released from lysed cancer cells diffuse into neighboring tumor cells, enhancing therapeutic efficacy—particularly in tumors with heterogeneous antigen expression. Despite its significance, methods for detecting and evaluating the bystander effect of ADCs remain under development. In this study, we present a robust approach to monitor and analyze the bystander effect of ADCs in real-time using live-cell imaging and impedance measurements with the Agilent xCELLigence RTCA eSight system. Two innovative assays—the in vitro co-culture assay and the conditioned medium transfer assay—were established for this purpose. The cytotoxic effects of DS8201, an ADC with bystander activity, and T-DM1, an ADC without bystander activity, were assessed in these assays. In the co-culture assay, HER2-positive SKBR3 cells and HER2-negative MCF7 cells were co-seeded in a biosensor plate (E-Plate VIEW 96) the day before testing. The results revealed that DS8201 treatment led to the death of HER2-negative MCF7 cells in the presence of SKBR3 cells, indicative of a bystander effect. In contrast, T-DM1 did not affect MCF7 viability under similar conditions. Both DS8201 and T-DM1, however, induced cytotoxicity in HER2-positive SKBR3 cells. In the conditioned medium transfer assay, medium from SKBR3 cells treated with DS8201 significantly reduced MCF7 cell viability, demonstrating a bystander effect. Conversely, conditioned medium from T-DM1-treated SKBR3 cells did not impact MCF7 viability. Notably, neither DS8201 nor T-DM1 exhibited direct cytotoxic effects on MCF7 cells in isolation. In conclusion, we describe two robust methodologies for detecting and evaluating the bystander effect of ADCs using the RTCA eSight system. These approaches provide valuable tools for optimizing the efficacy, safety, and pharmacokinetics of therapeutic ADCs during biopharmaceutical development. Citation Format: Xiaoyu Zhang, Yun-fei Pu, Tian Wang, Grace Yang, Peifang Ye, Nancy Li. In vitro real-time evaluation of bystander effects of antibody-drug conjugates [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 5476.
Abstract 5474: QUANTROseq, a transcriptomic based drug discovery platform using time-resolved gene expression profiling: identification of inhibitors and degraders of transcription factors and cell signaling regulators
Authors: Arianna Sabo
Journal: Cancer Research (2025)

Abstract Transcription factors (TFs) and related signaling pathways have long been considered among the most challenging targets in drug discovery. To address these limitations, QUANTRO Therapeutics has developed QUANTROseq, a pioneering transcriptomic discovery platform designed to match transcriptional dynamic profiles or “fingerprints” triggered by small-molecule drug candidates with those derived from controlled, acute degradation of specific targets. This innovative approach enables the identification of novel inhibitors, modulators, and degraders with unprecedented precision and sensitivity, targeting even previously undruggable proteins. Analysis of our data demonstrated that time-resolved transcriptional profiling not only allows identification of drug candidates in HTS screening, it also reveals the mode of action of these drugs with unprecedented precision and sensitivity, provided that these act on targets that have a direct effect on transcriptional regulation, such as transcription factors (TFs) and signaling pathways (e.g. c-MYC, YAP/TEAD or KRAS). This approach allows for the clear discrimination between molecules that directly act on a specific transcription factors or directly associated regulatory co-factors, and drugs that only indirectly affect its function. The transcriptional fingerprinting approach is employed by QUANTRO at various stages of the drug discovery process: 1. Benchmarking the real mode of action of existing drugs; 2. Interrogating the efficiency, selectivity, and potency of drug candidates during Hit-validation and Hit-to-Lead optimization activities, overcoming the limitation of standard biochemical/biophysical assays in their capacity to inform regarding compounds selectivity; 3. Identifying new mode of action drug candidates that specifically interfere with disease-causing transcriptional programs in cancer, through the proprietary QUANTROseq screening platform. During last year, QUANTROseq screening technology has been employed by QUANTRO in multiple large HTS screening campaigns, which yielded high quality hits against several key oncogenic transcription factors. Screening results will be presented at the conference. Citation Format: Arianna Sabo, QUANTRO Therapeutic Team. QUANTROseq, a transcriptomic based drug discovery platform using time-resolved gene expression profiling: identification of inhibitors and degraders of transcription factors and cell signaling regulators [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 5474.
Abstract 3209: IND enabling study of NRT-YHD_001, a macrophage immune checkpoint inhibitor in liver cancer
Authors: Suk Woo Nam, Jin Woong Ha, Sang Yean Kim, Min Jeong Na, Soyoung Jeon, Bee Yoo, In Seop Yoon, Hyunmin Lee, Chang Won Park
Journal: Cancer Research (2025)

Abstract NRT-YHD_001, a modified antisense miRNA targeting let-7i-5p for liver cancer therapy, acts as a key regulator of macrophage activity within the tumor microenvironment. Through in vitro pharmacology studies, we identified anticancer effects not only on cell growth, proliferation, viability, migration, and invasion but also through the enhancement of macrophage phagocytosis. To evaluate the in vivo efficacy of NRT-YHD_001, we used a Ras-transgenic mouse liver cancer model which develops spontaneous liver cancer mass after 15 ∼ 20 weeks of birth. Based on dose-dependent and injection interval studies, the optimal regimen was determined to be 1 mg/kg administered weekly. We confirmed that weekly intravenous injections of 1mg/kg NRT-YHD_001 showed significantly greater therapeutic efficacy than the sorafenib-treated group. Additionally, xenograft assay using human liver cancer cells in athymic-nude mice showed that weekly injection of NRT-YHD_001 led to improved survival and tumor growth inhibition compared to the untreated group. We performed Absorption, Metabolism, Distribution, and Excretion studies for NRT-YHD_001, stability studies in serum and liver homogenate, and metabolite identification and profiling analysis were completed in mice and cynomolgus monkeys. In maximum tolerated dose (MTD) studies conducted in mice and cynomolgus monkeys, no toxicity of NRT-YHD_001 was observed at doses up to 500 mg/kg administered intravenously. Furthermore, comprehensive evaluations across 4-week repeated dose toxicity and toxicokinetic in mice and monkey, safety pharmacology, and genetic toxicity studies revealed no adverse findings with NRT-YHD_001. For NRT-YHD_001, Drug Substance (DS) and Drug Product (DP) were produced by a global CDMO with experience in U.S. FDA approval of oligonucleotide drugs, and the analysis method was established.These results enabled us to complete the IND-enabling study package for NRT-YHD_001, a liver cancer therapy candidate with FTO analysis completed and intellectual property (IP) fully secured. Regulatory approval submissions to the Korea MFDS and the U.S. FDA are planned for 2025. Citation Format: Suk Woo Nam, Jin Woong Ha, Sang Yean Kim, Min Jeong Na, Soyoung Jeon, Bee Yoo, In Seop Yoon, Hyunmin Lee, Chang Won Park. IND enabling study of NRT-YHD_001, a macrophage immune checkpoint inhibitor in liver cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 3209.
Abstract 5451: JSKN021, an innovative site-specific dual-payload bispecific antibody drug conjugate targeting EGFR and HER3 exhibits potent preclinical activities
Authors: Ting Xu, Fan Li, Zhilong Lai, Rupeng Qu
Journal: Cancer Research (2025)

Abstract Background: EGFR and HER3, both belong to the EGFR family, are widely overexpressed in human malignancies, rendering them promising targets for cancer treatment. Cancer is a heterogeneous disease. Inter- and intratumor heterogeneity is believed to be a major factor contributing to recurrence, metastasis and resistance to current socs. To address these therapeutic challenges, we generated JSKN021, a dual payload ADC targeting EGFR/HER3. Both payloads, a novel DNA topoisomerase I inhibitor (T01, Alphatecan) and MMAE, are conjugated to glycan on Fc via cleavable linkers. The conjugation processes were carried out via combination of glycan transferase and click reaction. The streamlined process generated site specific and homogeneous conjugation with DAR4(T01)and DAR2 (MMAE).In this study, the pharmacological activity of JSKN021 was evaluated using relevant in vitro cell killing assays and in vivo models. Methods: A novel Topo 1 inhibitor T01 and MMAE were stably conjugated to an EGFR/HER3 mAb using a glycan based site-specific manner. The conjugated products were characterized by LC-MS. Binding specificity of JSKN021 was confirmed by ELISA. In addition, release of payload were evaluated by LC-HRMS. At last, in vitro cell growth inhibitory and in vivo antitumor activities of JSKN021 were evaluated using different cancer cell lines and CDX models in comparison to single payload ADCs. Results: After conjugation, LC-MS results showed that JSKN021 had a homogeneous DAR4 for T01 payload and DAR2 for MMAE. JSKN021 was demonstrated to bind EGFR and HER3 simultaneously. In addition, both T01 and MMAE were detected in cell culture supernatant and suspension of HCC827. Yet, no other metabolites were found detectable. JSKN021 demonstrated excellent stability in rats, mice, monkeys, and human serum, with minimal payload release. The stability was derived from the advantage of glycan based conjugation. JSKN021 inhibited the growth of cancer cells with either Her3 or EGFR or both expression, such as HCC827, MDA-MB-468, A431 and NCI-H1975. Furthermore, JSKN021 showed stronger tumor inhibition efficacy than mono payload ADCs in multiple CDX models. Conclusion: The preclinical studies suggest JSKN021, as a dual-payload EGFR/HER3 bispecific ADC, might be a promising novel antitumor therapeutic agent. Citation Format: Ting Xu, Fan Li, Zhilong Lai, Rupeng Qu. JSKN021, an innovative site-specific dual-payload bispecific antibody drug conjugate targeting EGFR and HER3 exhibits potent preclinical activities [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 5451.
Abstract 3802: Isoleucine and valine promote prostate cancer progression via propionyl-CoA-mediated cholesterol metabolism
Authors: Zhongchi Li, Shuchen Liu, Olivia Kester, Wenbing Jin, Un In Chan, Zhucui Li, Nayah Bullen, John Blenis
Journal: Cancer Research (2025)

Abstract Enhanced cholesterol synthesis and storage in lipid droplets are strongly associated with cancer aggressiveness, particularly in lipid-rich and hormone-sensitive cancers such as prostate cancer. While tumor cells tightly regulate cholesterol anabolism and catabolism in response to nutrient states, the mechanisms that sense nutrient status and drive these processes remain poorly understood. Emerging evidence highlights mitochondria as key hubs of signal transduction, with mitochondrial metabolites serving as pivotal signaling molecules. Our prior work identified that the propionate metabolism pathway is remodeled during metastasis, with metabolites from this pathway acting as signaling regulators. Notably, patient data reveal that elevated propionyl-carnitine levels in prostate tumor tissues correlate with increased tumor aggressiveness. To investigate the role of propionyl-CoA in prostate cancer progression, we manipulated its levels in prostate cancer cells and assessed its effects on proliferation, colonization, and lipid metabolism both in vitro and in vivo. We discovered that mitochondrial metabolism of branched-chain amino acids (BCAAs), specifically isoleucine and valine, is a major source of cellular propionyl-CoA. This metabolite drives the propionylation of sterol regulatory element-binding protein 2 (SREBP2), promoting cholesterol synthesis and storage. The accumulated cholesterol fuels steroidogenesis, facilitating prostate tumor growth, colonization, and therapeutic resistance. Our findings establish a direct link between amino acid metabolism and cholesterol anabolism, unveiling a novel mechanism of cholesterol regulation in prostate cancer progression. This study highlights the therapeutic potential of targeting propionyl-CoA production, particularly through the metabolism of isoleucine and valine, to disrupt cholesterol synthesis and combat prostate cancer progression. Citation Format: Zhongchi Li, Shuchen Liu, Olivia Kester, Wenbing Jin, Un In Chan, Zhucui Li, Nayah Bullen, John Blenis. Isoleucine and valine promote prostate cancer progression via propionyl-CoA-mediated cholesterol metabolism [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 3802.
Abstract 3212: IL2-mediated modulation of sEV secretion and PD-L1 expression: A novel perspective for neutralizing immune suppression within cancer cells
Authors: Soojeong Noh, Suyeon Ryu, Dokyung Jung, Sanghee Shin, Inseong Jung, Sung-Min Kang, Christine Seulki Kim, Sung-Jin Choi, Hanchae Cho, Melanie Schwämmle, Youngtae Jeong, Felicitas Bucher, Il-Kyu Choi, Shin Yup Lee, Sin-Hyeog Im, Kyungmoo Yea, Moon-Chang Baek
Journal: Cancer Research (2025)

Abstract IL2 is known to induce anticancer effects by activating immune cells expressing the IL2 receptor complex (IL2R). However, the potential impact of IL2 on cancer cells expressing IL2R, such as melanoma cells, has been understudied. Here, we demonstrate that IL2 significantly reduces the secretion of small extracellular vesicles (sEVs) and expression of programmed death ligand 1 (PD-L1) in melanoma cells, while increasing their sensitivity to CD8+ T cell-mediated cytotoxicity. These effects are mediated through the activation of IL2R-MEK/ERK signaling in melanoma cells. To evaluate the direct effects of IL2 on melanoma cells in vivo, we developed a mouse model in which melanoma cells were engineered to express IL2 on their surface for self-stimulation. In this model, IL2 stimulation inhibited tumor growth and reduced PD-L1 expression in tumor tissues and plasma. Similar patterns were observed in lung cancer clinical samples. Our findings suggest that IL2 can directly elicit an anticancer immune response in IL2R-bearing cancers, highlighting its potential application in immunotherapy as an immune checkpoint modulator. Citation Format: Soojeong Noh, Suyeon Ryu, Dokyung Jung, Sanghee Shin, Inseong Jung, Sung-Min Kang, Christine Seulki Kim, Sung-Jin Choi, Hanchae Cho, Melanie Schwämmle, Youngtae Jeong, Felicitas Bucher, Il-Kyu Choi, Shin Yup Lee, Sin-Hyeog Im, Kyungmoo Yea, Moon-Chang Baek. IL2-mediated modulation of sEV secretion and PD-L1 expression: A novel perspective for neutralizing immune suppression within cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 3212.
Abstract 4743: Defining the impact of anti-androgen pathway inhibitors on ABI1, dendritic spines and mouse behavior
Authors: Anna Seidl, Kevin M. Lin, Maria A. Ortiz, Leszek Kotula
Journal: Cancer Research (2025)

Abstract Prostate cancer (PCa) is the most commonly diagnosed cancer and the second leading cause of cancer-related deaths among American men. Following radiation therapy and surgery, patients are often treated with androgen deprivation therapy (ADT) or anti-androgen drugs to suppress tumor growth, as prostate cancer is highly androgen-dependent. However, emerging evidence highlights significant cognitive side effects, including dementia and behavioral changes, associated with anti-androgen treatments. While clinical trials are investigating these ‘treatment-induced’ cognitive deficits, the underlying mechanisms remain poorly understood. Our previous work revealed that the Androgen Receptor (AR) regulates Abelson Protein 1 (ABI1) expression in prostate tumors. ABI1, a key stabilizer of the WAVE complex, plays a critical role in actin polymerization and cytoskeletal reorganization. In dendritic spines, ABI1 supports the dynamic remodeling of the cytoskeleton essential for synaptic plasticity, a fundamental process underlying learning and memory. Disruption of ABI1 in hippocampal neurons results in abnormal dendritic spine morphology and impaired synapse formation, but there are no genetic studies on the role of Abi1 in cognitive performance in mouse models. Androgen deprivation, through surgical castration or ADT, has been shown to impair memory and behavior in mice. Given that ABI1 expression is downregulated by anti-AR therapy in prostate tumors, we hypothesize that ABI1 is similarly regulated by androgens in dendritic spines. We propose that AR suppression by ADT leads to reduced ABI1 expression in dendritic spines, contributing to cognitive and behavioral impairments in patients undergoing ADT. To test this hypothesis, we utilized a novel Abi1-selective knockout mouse model developed in our lab to explore the effects of ABI1 disruption on dendritic spines and behavior. Additionally, we compared dendritic spine morphology and ABI1 levels in the hippocampi of mice treated with anti-AR drugs, such as enzalutamide, or subjected to surgical castration. These results are being analyzed alongside findings from mice with genetic ABI1 disruption. This study provides critical insights into the role of ABI1 in dendritic spine dynamics and synaptic plasticity, uncovering a potential mechanistic link between ADT and cognitive dysfunction. Our findings aim to define the molecular basis of treatment-related cognitive deficits in PCa patients and may guide the development of strategies to mitigate these side effects. Citation Format: Anna Seidl, Kevin M. Lin, Maria A. Ortiz, Leszek Kotula. Defining the impact of anti-androgen pathway inhibitors on ABI1, dendritic spines and mouse behavior [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 4743.
Abstract 5452: Novel tryptophan-based antibody-drug conjugate (ADC) targeting EGFR-positive lung cancer demonstrates robust antitumor efficacy by triggering immunogenic cell death
Authors: Hiroyuki Inoue, Kounosuke Oisaki, Hiroshi Tagawa, Akira Nakao, Noriyuki Ebi, Takeshi Mori, Masaki Fujita
Journal: Cancer Research (2025)

Abstract Background and Aim: Antibody-drug conjugates (ADCs), which combine a cytotoxic small molecule drug with an antibody to enable targeted delivery at tumor sites, are emerging as next-generation therapeutic options for non-small cell lung cancer with HER2 mutations. However, clinical development of ADCs for solid tumors has been hindered by hematologic toxicity, such as thrombocytopenia, caused by FcγRIIa-mediated uptake into megakaryocytes (antibody-dependent cellular cytotoxicity: ADCC), as well as the prolonged time and high cost required for linker optimization at cysteine (Cys) or lysine (Lys) residues on antibodies. This study aimed to develop a novel ADC targeting the human EGFR surface antigen, which is expressed in a broad range of lung cancers, through collaborative research in pharmaceutical engineering. Method: We synthesized novel ADCs using our proprietary ABNO linker, which offers high stability through tryptophan (Trp) modification on anti-EGFR IgG4 antibodies. This approach allows for more homogeneous and stable ADC production at a lower development cost compared to conventional linkers. We assessed whether the synthesized ADCs eliminated ADCC activity in co-culture with NK cells and examined their ability to induce immunogenic cell death by evaluating calreticulin exposure on the surface of dying cancer cells. Results: We successfully synthesized a novel ADC (Anti-hEGFR(IgG4)-ABNO-DM-1: E4-AD) by conjugating the cytotoxic drug DM-1 to an anti-human EGFR-IgG4 antibody using the ABNO linker. In CKK8 assays, E4-AD demonstrated potent, concentration-dependent cytotoxic activity against EGFR-positive human lung cancer cell lines, with IC50 values ranging from 2 to 20 nM, while showing no cytotoxicity in EGFR-negative lung cancer cells. Furthermore, E4-AD effectively abolished NK cell-mediated ADCC in vitro and significantly increased calreticulin exposure on cell surface and HMGB-1 release from dying lung cancer cells, indicating the induction of immunogenic cell death. Conclusion: These findings suggest that the newly developed E4-AD, with its innovative tryptophan-based linker technology, holds promise as a safer and more effective ADC for treating EGFR-positive lung cancers. Citation Format: Hiroyuki Inoue, Kounosuke Oisaki, Hiroshi Tagawa, Akira Nakao, Noriyuki Ebi, Takeshi Mori, Masaki Fujita. Novel tryptophan-based antibody-drug conjugate (ADC) targeting EGFR-positive lung cancer demonstrates robust antitumor efficacy by triggering immunogenic cell death [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 5452.