bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5081: Immune sensitization of melanoma to checkpoint inhibitor therapy using acoustically active nanoparticles
Authors: Henderson Michael Ian , Xiang Li , Drennan Samuel , Yi Xin , Fischer Jared , Yildirim Adem
Published: March 2024

Advanced melanoma remains the most fatal form of skin cancer with novel therapeutic approaches required to treat inoperable metastatic lesions. While immunotherapies have shown promise in improving long-term melanoma survival, its treatment efficacy is limited, with only 50% of patients responding. Focused ultrasound (FUS) offers as a non-invasive strategy for targeted tumor ablation, thereby strengthening immunotherapy efficacy by release of tumor associated materials. However, control over tumor material release through FUS, without causing excessive thermal damage to surrounding healthy tissue remains challenging. To address this challenge, our group has previously developed acoustically active nanoparticles (AANPs) responsive to low intensity ultrasound for mechanical tumor ablation by generating strong and durable acoustic cavitation in the tumor tissue. Building upon previous success with AANPs, our current work focuses on sensitizing melanoma tumors to checkpoint inhibitor therapy by releasing tumor antigens into circulation using AANPs and FUS. Our findings revealed sensitization of an immunologically cold B16-F10 metastatic melanoma tumors following treatment, which resulted in a notable 12-day stall in tumor growth. When combined with immune checkpoint inhibitors α-PD-L1 and α-CTLA-4, this approach showed a complete response in B16-F10 bearing mice with impressive memory immune response upon a tumor rechallenge. Herein, these novel AANPs represent a promising advancement to enable accurate immune surveillance by boosting the release of tumor antigens and offers new strategies for improved immunotherapy of melanoma and other solid tumors.

Citation Format: Michael Ian Henderson, Li Xiang, Samuel Drennan, Xin Yi, Jared Fischer, Adem Yildirim. Immune sensitization of melanoma to checkpoint inhibitor therapy using acoustically active nanoparticles [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 5081.
Abstract 5090: Development of HSPG2 targeted glycoengineered antibody-drug conjugates
Authors: Li Xiaolei , Prabha Swayam
Published: March 2024

Ovarian cancer is associated with poor outcomes and aggressive behaviors. Although surgical removal of tumors and chemotherapy can initially eradicate cancer, many patients eventually experience relapse with chemotherapy-resistant tumors, resulting in poor long-term outcomes and chemotherapy complications. Antibody-drug conjugates (ADCs) are formed by integrating the tumor specificity provided by antibodies (Ab) and small molecule cytotoxicity drugs and can facilitate highly targeted delivery with minimal toxicity to normal tissues. Our group has identified that the overexpression of a novel target, heparan sulfate proteoglycan 2 (HSPG2), is associated with poor prognosis and survival of high grade serous ovarian cancer (HGSOC) patients. We have developed a monoclonal antibody (AM6) that effectively targets HSPG2-expressing tumors. In this study, we used a novel glycoengineering strategy to introduce artificial azide groups at the N-glycan sites of AM6 without affecting its antigen affinity and intracellular localization. The azide groups were then used for site-specific conjugation of the cleavable dibenzyl cyclooctyne - monomethyl auristatin E (DBCO-PAB-MMAE) linker (drug conjugate) to form an AM6 antibody-drug conjugate (AM6 ADCs). Hydrophobic interaction chromatography (HIC) and liquid chromatography/quadrupole time-of-flight/mass spectrometry (LC/Q-TOF/MS) confirmed the successful conjugation of the DBCO-PAB-MMAE to the AM6. In-vitro cytotoxicity studies of AM6 ADCs in OVCAR8 (high HSPG2 expression) and CAOV3 (regular HSPG2 expression) showed the cell line dependent response with lower IC50 in OVCAR8. These results suggest that the effectiveness of AM6 ADCs is proportional to the HSPG2 expression levels of the cells. Future studies will be aimed at the in-vivo evaluation of optimized antibody-drug conjugates.

Citation Format: Xiaolei Li, Swayam Prabha. Development of HSPG2 targeted glycoengineered antibody-drug conjugates [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 5090.
Abstract 511: Cell cycle inhibitors exhibit anti-tumor immunomodulatory roles through the HIF-1-DDX41 cytosolic DNA sensing pathway in HCC
Authors: Chan Cerise Yuen Ki , Wong Po Yee , Xue Helen Do Gai , Goh Chi Ching , Cheu Jacinth Wing Sum , Tse Aki Pui Wah , Zhang Misty Shuo , Wong Carmen Chak Lui
Published: March 2024

Cell cycle inhibitors have a long history as anti-cancer therapeutics in clinical applications. Uncontrolled and infinite cell cycles are hallmarks of cancer, which enable them to proliferate rapidly and survive. To target these key features of cancer cells, cell cycle inhibitors are used to arrest their active cell cycle and induce cell death. In this study, beyond the known primary effect on cell cycle control, we identified that an expected and a secondary effect in immune modulation by the cell cycle inhibitors. Anti-mitotic agents including Paclitaxel (microtubule stabilizer), Palbociclib (CDK4/6 inhibitor) and AZD1152 and GSK1070916 (Aurora Kinase B inhibitors) can also eliminate cancer cells via an alternative mechanism - the activation of STING signaling. Our results demonstrated that these anti-mitotic agents caused DNA damage and cytosolic DNA accumulation. The cytosolic DNA was captured by a cytosolic DNA sensor DDX41,which triggered STING-TBK1-IRF3/7 pathway to upregulate secretion of pro-inflammatory senescence-associated secretory phenotype (SASP) factors in cancer cells. In addition, we revealed that transcription of DDX41 was mediated by the transcription factor known ashypoxia-inducible factor (HIF). In HCC, hypoxia induced DDX41 expression through HIF-1,thus hypoxic HCC cells were more prone to STING activation and SASP production under mitotic stress induced by cell cycle inhibitors. In the tumor microenvironment, the SASP enhanced infiltration of immune cells into the tumor core to eliminate cancer cells. We also observed the additive effects of cell cycles inhibitors (Paclitaxel, Palbociclib, and AZD1152)with anti-PD-1 mAb to arrest growth of HCC in mouse models. In summary, this study exhibited the novel immune-mediated aspect of cell cycle inhibitors in suppressing tumor growth. Our data suggested the potential combination regimen of cell cycle inhibitors and currently available immunotherapy with promising result.

Citation Format: Cerise Yuen Ki Chan, Po Yee Wong, Helen Do Gai Xue, Chi Ching Goh, Jacinth Wing Sum Cheu, Aki Pui Wah Tse, Misty Shuo Zhang, Carmen Chak Lui Wong. Cell cycle inhibitors exhibit anti-tumor immunomodulatory roles through the HIF-1-DDX41 cytosolic DNA sensing pathway in HCC [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 511.
Abstract 5124: A CRISPR-drug perturbational map for identifying compounds to combine with commonly used chemotherapeutics
Authors: Wright William C. , Geeleher Paul
Published: March 2024

Combination chemotherapy is crucial for successfully treating cancer. However, the enormous number of possible drug combinations means discovering safe and effective combinations remains a significant challenge. To improve this process, we conduct large-scale targeted CRISPR knockout screens in drug-treated cells, creating a genetic map of druggable genes that sensitize cells to commonly used chemotherapeutics. We prioritize neuroblastoma, the most common extracranial pediatric solid tumor, where ~50% of high-risk patients do not survive. Our screen examines all druggable gene knockouts in 18 cell lines (10 neuroblastoma, 8 others) treated with 8 widely used drugs, resulting in 94,320 unique combination-cell line perturbations, which is comparable to the largest existing drug combination screens. Using dense drug-drug rescreening, we find that the top CRISPR-nominated drug combinations are more synergistic than standard-of-care combinations, suggesting existing combinations could be improved. As proof of principle, we discover that inhibition of PRKDC, a component of the non-homologous end-joining pathway, sensitizes high-risk neuroblastoma cells to the standard-of-care drug doxorubicin in vitro and in vivo using patient-derived xenograft (PDX) models. Our findings provide a valuable resource and demonstrate the feasibility of using targeted CRISPR knockout to discover combinations with common chemotherapeutics, a methodology with application across all cancers.

Citation Format: William C. Wright, Paul Geeleher. A CRISPR-drug perturbational map for identifying compounds to combine with commonly used chemotherapeutics [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 5124.
Abstract 5193: Molecular evolution of chemoresistance acquisition and predictive insights into the progression of bladder cancer
Authors: Yang Gi-Eun , Kim Jae-Jun , Shin Tae Hwan , Leem Sun-Hee
Published: March 2024

Cancer heterogeneity arises from cellular features, suggesting that distinct molecular drivers may be latent within cancers diagnosed at different clinicopathological stages. We thoroughly assessed phenotypic traits and molecular alterations linked to chemoresistance and constructed chemoresistant bladder cancer cell lines representing the stepwise transformation. Model cell lines (5637GRCs, gemcitabine-resistant cells) with stepwise gemcitabine resistance representing early, intermediate, and late resistance phases were developed from non-muscle-invasive bladder cancer (NMIBC) cells. Notably, an increase in cell motility was observed at a relatively early phase. The results from the time-course analysis of molecular evolution showed changes in focal adhesion kinase signaling, PI3K-Akt signaling, and TGF-β signaling pathways during the phase of increasing cell motility. As chemoresistance increased, the levels of genes related to differentiation and MAPK signaling gradually increased. A 63-gene chemoresistance-motility (CrM) signature was constructed and weighted according to cell motility, and a strong correlation was observed between cancer metastasis and drug resistance; the signature also showed prognostic relevance in patients with NMIBC. This study affords a significant understanding of the molecular evolution of chemoresistance acquisition and enables prediction of cancer progression during chemotherapy treatment. Moreover, it provides insights into the progression of cells through all chemoresistance stages from NMIBC to MIBC. Therefore, this study proposes the feasibility of utilizing biomarkers correlated with cancer motility to predict cancer progression in the early phase of chemotherapeutic intervention in patients with non-muscle-invasive bladder cancer.

Citation Format: Gi-Eun Yang, Jae-Jun Kim, Tae Hwan Shin, Sun-Hee Leem. Molecular evolution of chemoresistance acquisition and predictive insights into the progression of bladder 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 5193.
Abstract 5261: Immunologic signatures of peripheral blood cells in patients with advanced pancreatic cancer under lenvatinib-pembrolizumab maintenance therapy
Authors: Chung Vincent , Kos Ferdynand , Manual Edwin , Dempsey Shannon , Diamond Don J.
Published: March 2024

Background: The treatment of pancreatic cancer is limited by chemotherapy toxicities which impacts quality of life. This is a phase 2 clinical trial of lenvatinib and pembrolizumab as maintenance therapy in patients with advanced pancreatic cancer. We observed preclinical activity of this combination in pancreatic mouse models. We hypothesize that this combination may address unmet needs to minimize toxicities associated with standard treatments, stimulate anti-tumor T cell immunity, and improve the progression free and overall survival. Exploratory studies aim to characterize immune-related systemic changes in peripheral blood over the course of therapy and to identify global changes in expression of tumor-related genes in needle biopsy samples of liver metastatic lesions.

Methods: Multiplex gene expression analysis of unsorted peripheral blood mononuclear cells (PBMC) was performed using PanCancer Immune Profiling Panel on NanoString nCounter platform. PBMC samples from pre- through week 32 of treatment were assessed for differential expression of 730 immune profiling genes defining T cell functions and associated immune categories.

Results: PBMC immune profiling from 4/5 patients show a distinctive pattern of increased activation of T cells during the first 9 weeks of treatment followed by a sharp inhibition starting at weeks 9-12 after 3-4 cycles of treatment (CD3E, CD247, LCK, TBX1, TCF7, STAT4, IL2RG). Subsequent upregulation of macrophage-derived scavenger, inflammatory, and immunosuppressive gene expression patterns continued for the remainder of treatment (CD14, MSR1, MARCO, CD68, TGFB1, IL10RA). The median PFS of first 10 patients was 21.5 (9-32) weeks.

Conclusions: Immunotherapy resistance may be related to rapidly developing terminal differentiation and unresponsiveness of T cells in parallel with upregulation of macrophage-derived inflammatory and immunosuppressive processes. Studies are on-going to prevent inhibition of the T-cells.

Citation Format: Vincent Chung, Ferdynand Kos, Edwin Manual, Shannon Dempsey, Don J. Diamond. Immunologic signatures of peripheral blood cells in patients with advanced pancreatic cancer under lenvatinib-pembrolizumab maintenance therapy [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 5261.
Abstract 5268: Targeting DHX9 triggers interferon response and replication stress in small cell lung cancer
Authors: Murayama Takahiko , Nakayama Jun , Cai Kathy Q. , Miyata Kenichi , Efimov Andrey , Tan Yinfei , Zhou Yan , Campbell Kerry S. , Yang Yibin , Balachandran Siddharth , Cañadas Israel
Published: March 2024

Small cell lung cancer (SCLC) is the most lethal type of lung cancer. The uniqueness of this tumor consists of an initial exquisite response to chemotherapy. However, at relapse, which occurs nearly in all patients, the tumor is resistant to all available therapies, causing a premature death of the patient. Despite the addition of immune checkpoint blockade (ICB) therapy to standard chemotherapy, response rates are modest and only a very small fraction of SCLC patients responds to these therapies because of immunologically “cold” microenvironment. Activating innate immunity in cancer cells through cytoplasmic nucleic acid sensing pathways, a phenomenon known as “viral mimicry”, has emerged as an effective strategy to convert immunologically “cold” tumors into “hot”. Here, through a curated CRISPR-based screen of RNA Helicases, we identified DExD/H-box helicase 9 (DHX9) as a potent repressor of double-stranded RNA (dsRNA) in SCLC cells. Depletion of DHX9 induced accumulation of cytoplasmic dsRNA, which mainly derived from repetitive sequences of short interspersed nuclear elements (SINEs) and long interspersed nuclear elements (LINEs), and triggered tumor-intrinsic innate immunity. Intriguingly, ablating DHX9 also induced the aberrant accumulation of R-loops (DNA/RNA hybrids), which resulted in an increase of DNA damage-derived cytoplasmic DNA and replication stress in tumor cells, selectively killing them. In vivo, DHX9 deletion in SCLC tumor cells promoted a decrease in tumor growth while inducing a more immunogenic tumor microenvironment (TME), invigorating responsiveness to immune checkpoint blockade (ICB). These findings suggest that DHX9 is a crucial repressor of tumor-intrinsic innate immunity and replication stress, and represents a promising and unexplored target for SCLC and other “cold” tumor types where replication stress and genomic instability contribute to pathology.

Citation Format: Takahiko Murayama, Jun Nakayama, Kathy Q. Cai, Kenichi Miyata, Andrey Efimov, Yinfei Tan, Yan Zhou, Kerry S. Campbell, Yibin Yang, Siddharth Balachandran, Israel Cañadas. Targeting DHX9 triggers interferon response and replication stress in small cell lung 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 5268.
Abstract 527: Cancer cells in the resistant, endocycling cell state exhibit centrosome amplification
Authors: Purkerson Madison , Amend Sarah , Pienta Kenneth J.
Published: March 2024

Therapy resistance is one of the most common underlying causes of poor prognosis in cancer patients, ultimately driving fatal outcome. We have previous demonstrated that following chemotherapeutic stress, a subset of cancer cells undergo a mitotic skip and enter an endocycle, causing whole-genome duplication without division. This endocycling cell state is resistant to cytotoxic therapies and thus is an actuator of therapy resistance. Cells in the endocycling state eventually undergo depolyploidization and repopulate the tumor, observed clinically as a recurrence. We also demonstrated that the minus-end directed motor protein KIFC1, a mediator of centrosome clustering, has higher expression in cells following treatment. Centrosome amplification (CA) involves aberrations in centrosome number, where cells have 3 centrosomes. Cells with extra centrosomes create a multi-polar spindle during mitosis, which presents high risk for cell death and arrest, but cancer cells with CA avoid this by clustering extra centrosomes to create a pseudo-bipolar spindle. Based upon this data, we hypothesize that studying centrosome dynamics and abnormalities presents a window into better understanding endocycle biology and this novel mechanism of therapy resistance. Cancer cells were treated with LD50 dose of cisplatin and released from treatment for varying lengths of time. CA in endocycling cells increased from 59.2% to 100% during the treatment recovery period while maintaining identical levels of clustering. Endocycling cancer cells have a nearly 5-fold increase in declustered centrosomes compared to proliferative cells. Centrosomes in endocycling cells are displaced from the perinuclear region and toward the cell periphery. We hypothesize that centrosome number may indicate the number of times a cell has endocycled and provide insight into the timing and mechanism of mitotic bypass. Centrosomes play a major role in microtubule nucleation, affecting cell motility and polarity, and act as signaling platforms, enhancing signaling activation and specificity. Because of this, we hypothesize that CA may be a critical mechanism for endocycling cancer cells to survive and maintain this resistant cell state.

Citation Format: Madison Purkerson, Sarah Amend, Kenneth J. Pienta. Cancer cells in the resistant, endocycling cell state exhibit centrosome amplification [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 527.
Abstract 5283: Polyamine blockade therapy: A strategy to block immunosuppression in pancreatic cancer
Authors: Goode Joseph A.
Published: March 2024

Pancreatic ductal adenocarcinoma (PDAC) is lethal in 88% of patients and is characterized by a dense tumor microenvironment (TME) which impedes tumor entry of immune cells and delivery of therapeutics. Immunosuppressive myeloid populations of PDAC, including myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs), are known to not only support PDAC development but also impede the anti-tumor immune response elicited by therapeutic agents. To improve prognosis while maintaining tolerability, this study aims to target polyamine metabolism that is upregulated in the immunosuppressive myeloid populations and cancer cells to disrupt their contribution to PDAC progression and the immunosuppressive TME. We previously demonstrated that polyamine blockade therapy (PBT), via blocking biosynthesis with difluoromethylornithine (DFMO) and transport with a novel inhibitor (Trimer44NMe), elicits an anti-tumor response and improves median survival in PDAC engrafted immunocompetent mice. In the current study, PBT was found to lead to a selective reduction of the dominant MDSC subtype in PDAC, polymorphonuclear (PMN) MDSCs. Upon co-culturing of MDSCs with CD8+ T cells, PBT dampened MDSC-mediated suppression of T cell activity. These findings were corroborated by tracking Arginase 1, a driver of MDSC-mediated immunosuppression, which exhibited a significant decrease in response to PBT at both the activity and gene expression level. Ex-vivo generated M2 macrophages and TAMs treated with PBT also demonstrated a shift from the M2 pro-tumor phenotype towards the anti-tumor M1 macrophage phenotype. In summary, these findings support that PBT is effective at reducing myeloid-mediated immunosuppression through subtype specific modulation and supports the use of PBT for treatment of PDAC in combination with other immunomodulatory therapeutics.

Citation Format: Joseph A. Goode. Polyamine blockade therapy: A strategy to block immunosuppression in pancreatic 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 5283.
Abstract 5288: Soy isoflavone genistein reboosts targeted therapy sensitivity in triple negative breast cancer
Authors: Bankole Taiwo , Li Zhenhai , Li Yuanyuan
Published: March 2024

Triple-negative breast cancer (TNBC) is a very aggressive type of breast cancer that does not expression important proteins called estrogen, progesterone and HER2. This makes TNBC hard to treat because it does not respond to common targeted treatments. However, recent treatments using the immune system to target key immune proteins such as PD-1 and PD-L1 have been successful in many types of cancer. This form of immunotherapy works by blocking PD-1/PD-L1 pathway and leads to stimulating the body's own immune system to recognize and attack cancer cells, thus providing a potential new treatment option for TNBC patients. Nevertheless, only approximately 30% of TNBC patients may respond to these drugs, suggesting the majority of TNBC patients would not benefit from these innovative immunotherapies. It is believed that low levels of immune cells and PD-L1 expression in tumors are the primary reasons for the lack of response or resistance to anti-PD-1/PD-L1 treatments. The use of nontoxic and healthy food and nutrition to increase treatment response is an emerging field of cancer research. Our studies showed that adding genistein (GE), a bioactive dietary component found in soybean products such as soy milk, soy protein and tofu, could significantly enhance the efficacy of anti-PD-1 immunotherapy in a TNBC mouse model that was previously not responsive to the treatment. Our research also found that soybean GE can increase tumor immune response by significantly recruiting active immune cells into the tumor and increasing PD-L1 expression. Our studies will help to establish a novel nutrition-based intervention targeting TNBC patients who might not qualify for this treatment initially. Eventually, we will develop a novel strategy of administering a tailored dietary plan to resensitize these patients to emerging anti-PD-1/PD-L1 immunotherapies.

Citation Format: Taiwo Bankole, Zhenhai Li, Yuanyuan Li. Soy isoflavone genistein reboosts targeted therapy sensitivity in triple negative breast 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 5288.
Abstract 5295: Tumor targeted-CD28 bispecific antibody with optimized potency, robust anti-tumoral activity and stringent CD3-dependence
Authors: Zhang Xiguang , Cao Shiqi , Li  , Zhou Shuaixiang , Xiong Yao , Kang Dian , Wang Feifei , Ren Jie , Fei Keke , Wang Jianglu , Lu Jinchang , Xiong Huizhong
Published: March 2024

CD28 is an essential co-stimulatory signal (Signal 2) for optimal T cell function upon TCR/CD3 activation (signal 1). However, clinical development of CD28 agonist antibodies has been confounded by toxicities presumably from CD3-independent and/or tumor non-specific activation. Here we report a rationally screened CD28 agonist antibody with optimized potency, from which a PSMAxCD28 bispecific was made. The bispecific antibody had several unique features: (1) minimal activity in the absence of CD3, even under stringent conditions, (2) superior tumor killing in vivo alone and in combination with anti-PD1 antibody, (3) requirement of abundant level of PSMA for activation, sparing PSMAlow cells, and (4) extended half-life in human-CD28 KI mice. To summarize, our anti-CD28 bispecific antibody enhances dependence on TCR/CD3 (Signal 1), induces selective killing of PSMA high expressing cancer cells, and elicits robust tumor eradiation in-vivo with extended PK. These features may translate to further improvements in efficacy and safety for tumor-targeted CD28 bispecific antibodies.

Citation Format: Xiguang Zhang, Shiqi Cao, Li, Shuaixiang Zhou, Yao Xiong, Dian Kang, Feifei Wang, Jie Ren, Keke Fei, Jianglu Wang, Jinchang Lu, Huizhong Xiong. Tumor targeted-CD28 bispecific antibody with optimized potency, robust anti-tumoral activity and stringent CD3-dependence [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 5295.
Abstract 5300: BH3120, PD-L1 X 4-1BB bispecific antibody, plus PD-1 antagonist results in synergistic anti-tumor efficacy with excellent safety profile
Authors: Wang Jun , Wang Jing , Liu Yang , Xu Jiangcheng , Liu Jiawang , Lee Kyoungwoo
Published: March 2024

BH3120 is a clinical stage PD-L1 binding dependent 4-1BB agonist with moderate affinity against 4-1BB. In multiple preclinical evaluations, BH3120 decoupled T cell modulation in TME from that in normal tissues, indicating potential decoupling of efficacy from safety concerns.

4-1BB agonism improves T cell functions in TME, combining BH3120 and PD-1 antagonist shows dose dependent and complete control of established tumor burden with bi-directionally synergistic mechanism: Blockade of PD-1 increases the expression and exposure of surface PD-L1, providing BH3120 more chance to form immune clusters in the tumor environment. In the meantime, increased PD-1 induced by BH3120 can be blocked by PD-1 antagonist.

This bi-directional mechanism results in rapid eradication of tumor tissues shortening the time to regression, indicating potentially fast control of tumor burden and associated symptoms. With the characteristics decoupling co-stimulatory activity in TME from that in normal tissues, BH3120 either as a monotherapy or in combination with PD-1 antagonist was not associated with liver toxicity and other concerns in relation to excessive modulation of immune cells systemically.

Safety profile and clinical signs with BH3120 are being investigated in early-stage clinical trials as a monotherapy and in combination with a PD-1 antagonist.

Citation Format: Jun Wang, Jing Wang, Yang Liu, Jiangcheng Xu, Jiawang Liu, Kyoungwoo Lee. BH3120, PD-L1 X 4-1BB bispecific antibody, plus PD-1 antagonist results in synergistic anti-tumor efficacy with excellent safety profile [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 5300.
Abstract 5324: Key antiviral response genes mediate the impact of chromosomal instability on breast cancer stemness
Authors: Baba Shahnawaz A. , Mugisha Samson , labhsetwar Shreyas , klemke Richard , Desgrosellier Jay
Published: March 2024

Chromosomal instability (CIN) is a recognized hallmark of cancer, pivotal in tumor evolution and metastasis. Our research unveils CIN as a stress during tumor initiation, uniquely tolerated by activated breast cancer stem cells (aCSCs). Elevated CIN, specific to tumors from aCSCs, contrasts with baseline levels akin to non-stem cell types. This transient increase in CIN, observed in low burden aCSC tumors, diminishes in established disease, suggesting a dynamic induction during initiation. Consist wit this we have observed increase in CIN tolerance in stem-like vs basal-like cells suggesting heterogeneity in response. CIN triggers a specific response, activating proinflammatory cancer autonomous immune signaling. We identified several CIN-induced proinflammatory stem cell-specific genes from our overlap studies. Knockdown assays targeting RSAD2 and PLAU showed a significant decrease in tumorsphere properties, emphasizing their functional relevance for cancer progression. AXL did not show any effect on tumorsphere but was important to tolerate CIN induced due to reversine. Mechanistically, AXL expression was induced by c-Jun stress signaling activation in aCSCs. These antiviral CIN-induced proinflammatory markers, emerge as a vital player in breast cancer progression. This study establishes a foundation for investigating antiviral genes as crucial contributors to cancer.

Citation Format: Shahnawaz A. Baba, Samson Mugisha, Shreyas labhsetwar, Richard klemke, Jay Desgrosellier. Key antiviral response genes mediate the impact of chromosomal instability on breast cancer stemness [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 5324.
Abstract 5331: Spatial resolution of immune cell lineages in the tumor microenvironment of plasma cell dyscrasias
Authors: Dillon Medbh A. , Arvidson Lisa , Phalen Cole G. , Ishibashi Julian R. , Johanneson John B. , Thomson Zachary J. , Zhao Peiyao A. , Malone Jocelin , Kopp Mackenzie S. , Norton Matthew , Spang Gabriella , Ludmann Susan A. , Savage Adam K. , Gustafson Claire E. , Glass Marla , Kuan Emma L. , Peng Tao , Graybuck Lucas T. , Li Xiao-jun , Torgerson Troy R. , Skene Peter J. , Goldrath Ananda W. , Jensen Samuel , Anover-Sombke Stephanie , Angus-Hill Melinda L.
Published: March 2024

Plasma cell dyscrasias (PCDs) are diseases of the hematologic system, with Multiple Myeloma as the most common disease. Less common PCDs include primary and secondary extramedullary plasmacytomas (EMP), which occur in soft tissues. EMPs are typically solitary and infrequent, often localized in the upper aerodigestive and gastrointestinal tracts, lung, and lymph nodes among other organs, and can convert to Multiple Myeloma. Secondary extramedullary plasmacytomas are often noted in advanced disease following multiple rounds of therapy and are commonly associated with poor prognosis. Studies aimed at gaining a better understanding of soft tissue EMPs, whether solitary plasmacytomas with undiagnosed multiple myeloma or in the context of recurrent or metastatic EMP disease, are limited. In this study, we employ a comprehensive approach using multiple modalities, including dissociated CITE-seq, spatial transcriptomics, and multiplexed spatial immuno-fluorescence imaging to interrogate the tumor and immune landscape in EMP disease. Importantly, the use of the same biomarker antibodies across these modalities provides a cross-data-framework for a deep contextual understanding of the immune and tumor cell organization and cell-to-cell signaling in EMP. Ultimately, this study provides new insights into patient-to-patient and tumor location variability, tumor and immune cell microenvironment heterogeneity, and possible future therapeutic strategies for EMP.

Citation Format: Medbh A. Dillon, Lisa Arvidson, Cole G. Phalen, Julian R. Ishibashi, John B. Johanneson, Zachary J. Thomson, Peiyao A. Zhao, Jocelin Malone, Mackenzie S. Kopp, Matthew Norton, Gabriella Spang, Susan A. Ludmann, Adam K. Savage, Claire E. Gustafson, Marla Glass, Emma L. Kuan, Tao Peng, Lucas T. Graybuck, Xiao-jun Li, Troy R. Torgerson, Peter J. Skene, Ananda W. Goldrath, Samuel Jensen, Stephanie Anover-Sombke, Melinda L. Angus-Hill. Spatial resolution of immune cell lineages in the tumor microenvironment of plasma cell dyscrasias [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 5331.
Abstract 5339: Establishment of a humanized IL5/IL5RA mouse model to evaluate modulators of eosinophilic inflammation in vivo
Authors: Zhao Suman , Zhang Shujin , Chen Zhen , Yang Liya , Kuraguchi Mari , Yuan Jiangfeng , Shen Heiling
Published: March 2024

IL-5/IL-5R signaling plays a key role in the maturation, activation, survival, and recruitment of eosinophils to sites of inflammation. Targeting this pathway is an attractive therapeutic strategy for certain inflammatory diseases, such as asthma. Here, we generated a novel humanized IL5/IL5RA model (B-hIL5/hIL5RA) to examine the utility of human IL-5/IL5R-targeting therapeutic candidates. Specifically, the entire murine Il5 coding region was replaced by the corresponding human IL5 sequence, and the human IL5RA sequence coding the extracellular domain was inserted to replace the corresponding murine sequence. Successful generation of the model was confirmed by expression of human IL-5 by ELISA and IL5RA by flow cytometry. Furthermore, the proportion of eosinophils in the blood of B-hIL5/hIL5RA mice increased after stimulation with human IL5 recombinant protein, indicating that the humanized IL5RA protein is functional. Next, the ability of the humanized mice to establish asthma-like disease was tested using ovalbumin: following a 14 day sensitization period, mice were challenged with nebulized OVA daily from day 21 until the endpoint; treatment with mepolizumab or benralizumab analog was performed. Flow cytometric analysis of the bronchioalveolar fluid indicates that treatment with mepolizumab or benralizumab analog significantly lowered the number of eosinophils when compared to the isotype control in homozygous B-hIL5/hIL5RA mice. Blood counts and quantification of lung H&E sections also confirm that the treatments lowered the number of eosinophils in circulation and lung tissue, respectively. Taken together, these data indicate that B-hIL5/hIL5RA mice are a suitable preclinical model to test novel modulators of human IL-5/IL-5RA signaling.

Citation Format: Suman Zhao, Shujin Zhang, Zhen Chen, Liya Yang, Mari Kuraguchi, Jiangfeng Yuan, Heiling Shen. Establishment of a humanized IL5/IL5RA mouse model to evaluate modulators of eosinophilic inflammation in vivo [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 5339.
Abstract 5350: Decr2 regulates tumor cell ferroptosis and immunotherapy efficacy
Authors: Li Shuyin , Shapiro Jason , Shah Hardik , Higgs Emily F. , Xie Lishi , Zha Yuanyuan , Trujillo Jonathan , Cabanov Alexandra , Jones Tyler A. , Flood Blake , Hatogai Ken , Kline Justin , Gajewski Thomas F.
Published: March 2024

Checkpoint blockade therapies have transformed the landscape of cancer care. Durable clinical responses have been observed in a subset of patients. However, many patients do not respond, and understanding the mechanisms that determine tumor resistant to checkpoint blockade drugs could potentially benefit more patients. Ferroptosis is a relatively newly described form of regulated cell death distinct from apoptosis and necroptosis. Recently, T cell-promoted tumor ferroptosis was shown to be an anti-tumor mechanism and targeting this pathway could be a potential therapeutic approach. To identify genes critical to immunotherapy resistance, B16.SIY cells were transduced with a genome-scale gRNA lentivirus to generate loss of function mutants. In vitro-primed CD8+ T cells isolated from 2C/Rag2-/- TCR transgenic mice specific for the SIY antigen were co-cultured with transduced B16.SIY tumor cells. Resistant mutants were identified by deep sequencing of survival clones. The gene encoding Decr2, a peroxisomal 2,4-dienoyl-CoA reductase, was identified. Decr2 mutants were relatively resistant to CD8+ T cell killing in vitro. Consistent with this resistance to CD8+ T cell killing, Decr2 knock-down tumors showed minimal response to anti-PD-L1 therapy in vivo. Tumor microenvironment analysis in Decr2 knockdown B16.SIY tumors showed failed antigen specific CD8+ T cells’ expansion and less IFN-γ production after anti-PD-L1 treatment. Knock-down of Decr2 resulted in diminished ferroptosis, triggered either by pharmacologic inducers or antigen-specific CD8+ T cells. Mechanistic studies revealed that Decr2 knockdown resulted in diminished induction of polyunsaturated ether phospholipids (PUFA-ePLs), which is due to reduced polyunsaturated ether phospholipids synthesis rate . Analysis of melanoma tumors from human patients revealed that up-regulation of Decr2 was associated with anti-PD-1 efficacy. Our results proved Decr2 knock down suppressed tumor ferroptosis and confer tumors resistance to anti-PD-L1 therapy by reducing the polyunsaturated ether phospholipids (PUFA-ePLs) synthesis.

Citation Format: Shuyin Li, Jason Shapiro, Hardik Shah, Emily F. Higgs, Lishi Xie, Yuanyuan Zha, Jonathan Trujillo, Alexandra Cabanov, Tyler A. Jones, Blake Flood, Ken Hatogai, Justin Kline, Thomas F. Gajewski. Decr2 regulates tumor cell ferroptosis and immunotherapy efficacy [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 5350.
Abstract 5387: Host-derived CCL2 drives prostate cancer bone metastasis via CCND2/STAT3 pathway
Authors: Meng Jie , Chang Ming , Qin Siyuan , Huang Xin , Liang Weiping , Tong Haibo , Zhang Jian
Published: March 2024

Overexpression of tumor-derived CCL2 has been shown to partially promote prostate cancer (PCa) bone metastasis, but the function of host-derived CCL2 is not fully understood. We first developed a mouse model using intracardiac injection and obtained highly metastatic PCa cell subclones through in vivo selection. The highly metastatic tumor cells were injected intracardially into CCL2 knockout (CCL2 KO) mice and wild-type (WT) controls, and the tumor cell growth and metastasis were monitored weekly by bioluminescence imaging. The osteolytic lesions were evaluated by radiography, micro-computed tomography (microCT) and immunohistochemistry (IHC) staining. The cells in the bone microenvironment were analyzed by flow cytometry. Also, RNA sequencing (RNA-seq) analysis was performed on the cells either from CCL2 KO mice or WT controls. We found that a loss of host-derived CCL2 significantly retarded tumor growth in bone and prolonged mouse survival. In addition, bone density analysis revealed a decrease in osteolytic lesion in CCL2 KO mice, compared to WT controls. Systemically, CCL2 deficiency reduced the proportion of granulocyte-myeloid-derived suppressor cell (G-MDSC) populations with immunosuppressive function and decreased the PCa conditioned medium (CM)-induced osteoclast formation. The enrichment analysis revealed that the dysregulated genes in bone metastatic cells from CCL2 KO mice were significantly enriched in several biological processes, including vitamin metabolism, monoatomic anion homeostasis, immune response, and bone growth. Additionally, we also confirmed that the CCND2/STAT3 pathway is apparently suppressed in the cells from CCL2 KO mice. This study demonstrated that targeting the host-derived CCL2 might be a novel potential anti-metastatic approach. Supported by the NSFC projects (81972766, 81972420, 82173336), as well as grants from the Science and Technology Project of Shenzhen (JCYJ20190809161811237, JCYJ20210324104214040).

Key words Host-derived CCL2; Prostate cancer; Bone metastasis; osteoclast; CCND2

Citation Format: Jie Meng, Ming Chang, Siyuan Qin, Xin Huang, Weiping Liang, Haibo Tong, Jian Zhang. Host-derived CCL2 drives prostate cancer bone metastasis via CCND2/STAT3 pathway [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 5387.
Abstract 5397: Characteristics of cancer associated fibroblasts isolated from refractory colorectal cancer using RNA sequence
Authors: Kasashima Hiroaki , Fukui Yasuhiro , Yonemitsu Ken , Kitayama Kisyu , Miki Yuichiro , Yoshii Mami , Fukuoka Tatsunari , Tamura Tatsuro , Shibutani Masatsune , Toyokawa Takahiro , Ree Shigeru , Yashiro Masakazu , Maeda Kiyoshi
Published: March 2024

Primary tumor location of colorectal cancers (CRCs) is emerging as an important prognostic factor owing to distinct biological features. In fact, the patients with right-side CRCs (R-CRCs), in which primary tumors were resected in our department and followed by systemic chemotherapy, have a poorer prognosis in 2-year overall survival and progression-free survival than those with left-side CRCs (L-CRCs). Furthermore, cancer-associated fibroblasts (CAFs) promote tumor malignancy, but the precise transcriptional mechanisms regulating the acquisition of the CAF phenotype are not well understood. Here, we isolated the CAFs and normal counterparts from 10 CRCs which were performed radical resection, including 5 L-CRCs and 5 R-CRCs, and analyzed transcriptomic profile of CAFs by RNA-sequencing. Gene Set Enrichment Analysis (GSEA) was performed and inflammatory signatures, such as "HALLMARK IL2 STAT5 SIGNALING"(NOM p-value<0.001, FDR q-value=0.146), "HALLMARK IL6 JAK STAT3 SIGNALING"(NOM p-value=0.014, FDR q-value=0.162), "HALLMARK INTERFERON GAMMA RESPONSE"(NOM p-value=0.032, FDR q-value=0.1726), were enriched in the CAFs isolated from R-CRCs (R-CAFs). In addition to sidedness of CRCs, based on gene expression profiles from bulk tumors, CRCs were classified into four consensus molecular subtypes (CMS1-4). Among them, The fibrotic CMS4 subtype portends poor relapse-free survival. We identified 4 CMS4-CRCs, which have the characteristics of stromal activation and the worst prognosis among other CRCs. GSEA showed that the signature of "HALLMARK TNFA_SIGNALING_VIA_NFKB" (NOM p-value=0.023 FDR q-value=0.207), "HALLMARK GLYCOLYSIS" (NOM p-value=0.036 FDR q-value=0.239) were upregulated in the CAFs isolated from CMS4-CRCs. These results indicated that CAFs isolated from refractory CRCs have unique phenotypes and the elucidation of these mechanisms might lead to a promising treatment for refractory CRCs.

Citation Format: Hiroaki Kasashima, Yasuhiro Fukui, Ken Yonemitsu, Kisyu Kitayama, Yuichiro Miki, Mami Yoshii, Tatsunari Fukuoka, Tatsuro Tamura, Masatsune Shibutani, Takahiro Toyokawa, Shigeru Ree, Masakazu Yashiro, Kiyoshi Maeda. Characteristics of cancer associated fibroblasts isolated from refractory colorectal cancer using RNA sequence [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 5397.
Abstract 5412: In vitro plasticity profiling of metastatic cancer cells with an imaging-based pipeline
Authors: Sameri Saba , Das Durdam , Michaelis Stefanie , Wegener Joachim , Hosseini Hedayatollah , Hoffmann Martin
Published: March 2024

Different types of cancer cells exhibit varying levels of invasiveness, migration behavior and ability to resume growth at distant sites. In order to classify cell lines for these fundamentally important traits of metastasis, we sought to generate an image-based in vitro assay that quantifies morphological and functional features of cancer cell plasticity. We developed an Imaging-Based Pipeline as an R Package for in vitro cell monitoring using the breast cancer cell lines MDA-MB-231 and MCF-7 that represent high-metastatic and low-metastatic cells in vivo, respectively, to identify relevant feature variables. Live cell imaging via the zenCELL owl system captured images for labeling and segmentation. Pre-trained neural network models from Cellpose, combined with user-calibrations, accurately segmented cells for tracking. The tracking pipeline calculated similarity coefficients, Jaccard index, between consecutive frames for cell trajectory analysis. Geometric and morphological features, speed, and distance measurements were derived for assessing structural motility and proliferation-associated changes. The analysis of two cell line models revealed significant variations in morphological changes, with MDA-MB-231 showing more rapid changes between round and elongated shape compared to MCF-7 cells. Moreover, the analysis of cell motility, consistent with the morphological changes, revealed that TGF-beta1 induced migration in MDA-MB-231 cells much stronger than in MCF-7 cells. Likewise, differences in proliferation induction upon addition of growth factor was monitored, showing that MCF-7 cells are more responsive to the growth stimulation than MDA-MB-231 cells. Consequently, the morphological plasticity of cancer cells, closely linked to the epithelial-to-mesenchymal transition (EMT) state, emerges as a defining factor for the in vitro plasticity of these cells. Quantified proliferation rate and migration speed of the cells was then used to establish an in vitro "plasticity index" that captures a cell line’s ability to switch between migration and proliferation. This index will undergo validation using cell lines with well-established metastatic propensities.

In conclusion, we developed an Imaging-Based Pipeline that can effectively explore cancer cell plasticity in vitro and monitor the impact of genetic or pharmacologic perturbations on this critical characteristic of aggressive cancer cells.

Citation Format: Saba Sameri, Durdam Das, Stefanie Michaelis, Joachim Wegener, Hedayatollah Hosseini, Martin Hoffmann. In vitro plasticity profiling of metastatic cancer cells with an imaging-based pipeline [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 5412.