bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract B022: Acinar-to-ductal metaplasia index (ADMI): A quantifiable measure of ADM
Authors: Aney Katherine J , Jeong Woo-Jeong , Koak Pal , Nissim Sahar
Published: September 2024

Acinar to ductal metaplasia (ADM) is thought to be a natural adaptive response to injury by which downregulation of digestive enzymes mitigates tissue damage and facilitates repair. However, this latent plasticity is also a critical gateway to cancer. In the context of a KRAS mutation – the driver mutation in pancreatic cancer – ADM is co-opted, causing acinar cells to progress into precancerous lesions instead of returning to a normal acinar state. ADM has various stages of severity marked by severe histologic changes replacing acinar morphology and markers with those of ductal epithelium. While this descriptive state of ADM is well established in pancreas biology, the field has lacked an objective measure to quantify various stages of deviation from the homeostatic acinar cell state. Here, we leverage FixNCut, a novel method for single-cell transcriptomic analysis of the pancreas, to develop an index tool that allows researchers to objectively measure the deviation of metaplastic acinar cells from normal acinar cell identity. The ADM Index, or ADMI, is based on 16 signature genes upregulated only in acinar cells in ADM, and is corroborated with GeoMx WTA data. We observe an increased ADMI score in acinar cells following pancreatitis, with perduring detectable elevation of ADM specific genes 14 days post-inflammation. ADMI was also validated in independent single-cell and bulk RNA-seq data, demonstrating the utility of scoring ADMI across studies and in diverse perturbations. We further apply ADMI to the context of recurrent weekly acute pancreatitis in mice and observe progressively increasing ADMI score sequentially at 2 week, 4 week, and 6 week timepoints. Our findings validate ADMI as a robust, objective standard that researchers can use in their own datasets to quantify deviation of individual acinar cells from normal identity, to investigate single-cell heterogeneity of these deviations, and to observe how these deviations change over time or following diverse stressors.

Citation Format: Katherine J Aney, Woo-Jeong Jeong, Pal Koak, Sahar Nissim. Acinar-to-ductal metaplasia index (ADMI): A quantifiable measure of ADM [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B022.
Abstract B023: Unravelling fibroinflammatory and immune signatures for pancreatic cancer early detection
Authors: Fraser Kyra , Rosado Maria , Pereira Stephen P , Acedo Pilar
Published: September 2024

Pancreatic cancer is associated with late-stage diagnosis and poor patient prognosis. The disease is characterised by chronic dysregulated immunity and inflammation. Moreover, chronic pancreatitis is linked with an increased risk of pancreatic cancer. Tissue remodelling during disease progression involves a complex network of cells and a crosstalk between cancer cells, stromal components and immune cells, but it remains poorly explored. Thus, to improve the outcome of patients, there is a need for better understanding of biological changes associated with the initiation and progression of pancreatic cancer at the molecular and spatial levels. Using samples obtained from our Accelerated Diagnosis of neuroEndocrine and Pancreatic TumourS (ADEPTS) biobank, we have evaluated blood samples for the discovery of non- invasive biomarkers to discriminate patients with pancreatic cancer from symptomatic patients without cancer. In this pilot study, the transcriptome of peripheral blood mononuclear cells (PBMCs), isolated using a ficoll gradient was explored to identify PDAC-associated mRNA signatures. Moreover, the Olink® Explore Inflammation and Oncology panels were performed in a cohort of 40 patients with early stage (I-II) PDAC, 40 chronic pancreatitis samples and 40 control patients with benign symptomatic upper GI diseases. To validate and enrich these results, a panel of inflammatory and immune markers including immunoglobulins, cytokines and chemokines was also run using multiplex techniques. Symptoms observed in our cohort were also analysed together with clinical (e.g diabetic status, biochemistry profile) and demographic data (age, sex, ethnicity, post code etc). We have identified mRNA transcriptome signatures and differentially expressed proteins associated with inflammatory and immunological processes in PDAC compared to benign symptomatic samples. Our results offer potential diagnostic utility for early-stage disease. Additionally, our unique cohort of patient samples comprising of those with confirmed PDAC and those presenting to clinic with benign disease and similar non-specific symptoms, allows for the development of non-invasive diagnostic tests with better translational applicability. Future work will involve the validation of these findings in a larger patient cohort and the use of NanoString GeoMx® Digital Spatial Profiler to perform whole transcriptome and proteome profiling in human chronic pancreatic and pancreatic cancer tissue samples.

Citation Format: Kyra Fraser, Maria Rosado, Stephen P Pereira, Pilar Acedo. Unravelling fibroinflammatory and immune signatures for pancreatic cancer early detection [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B023.
Abstract B026: Development of a Urinary miRNA-Based Classifier for Detecting Pancreatic Cancer in High-Risk Groups
Authors: Kawase Tomoya , Kusaka Hiroyasu , Yoshida Koji , Kato Yasutaka , Kita Junji , Kurahara Hiroshi , Kondo Shunsuke , Satomura Atsushi , Yoshida Yuji , Yamaguchi Hiroki , Ando Yoriko , Mikami Motiki , Mizunuma Mika , Ichikawa Yuki
Published: September 2024

Background Despite advances in treatment for cancer, the 5-year survival rate of pancreatic adenocarcinoma(PDAC) remains approximately 10% as of 2023. Early detection of PDAC is crucial for improving therapeutic outcomes. In order to detect PDAC at early stages, monitoring patients with clinical risk factors is important but relying solely on these risk factors is not sufficient. There is an urgent need for detection of biological markers such as microRNAs (miRNAs). In this study, we analyzed urinary miRNAs as a potential non-invasive biomarker and developed a machine learning classifier to detect pancreatic cancer from high-risk patients. Method A total of 165 participants with Stage0 to Ⅳ PDAC and 109 high-risk participants were analyzed. High-risk patients were defined as those who had at least one of the following diseases and/or risk factors: type 2 diabetes, chronic pancreatitis, intraductal papillary mucinous neoplasm, pancreatic cysts, dilation of main pancreatic duct and family history of PDAC. Urinary miRNA were sequenced by next generation sequencer. The data were split into 80% of training data and 20% of validation data for the development of a classifier. Machine learning based algorithm was deployed to construct an algorithm from the training data and its performance was evaluated by the remaining validation data. Results: Differential expression analysis revealed 12 upregulated and 7 downregulated miRNAs. Among downregulated miRNAs, PDAC related pathways such as growth signaling were significantly enriched. The performance of the classifier was AUC: 0.87, sensitivity: 0.80, and specificity 0.77. The sensitivity for early stage (Stage0-Ⅰ)PDAC was 0.80 and 0.88 especially when limited to StageⅠ. Conclusion: The classifier was able to detect PDAC at early stages with high sensitivity and specificity. This study demonstrated the potential for effective monitoring of high-risk patients for the early detection of PDAC, highlighting the feasibility and advantages of urine sampling due to its simplicity. To further evaluate the performance of the algorithm, a validation study is recommended.

Citation Format: Tomoya Kawase, Hiroyasu Kusaka, Koji Yoshida, Yasutaka Kato, Junji Kita, Hiroshi Kurahara, Shunsuke Kondo, Atsushi Satomura, Yuji Yoshida, Hiroki Yamaguchi, Yoriko Ando, Motiki Mikami, Mika Mizunuma, Yuki Ichikawa. Development of a Urinary miRNA-Based Classifier for Detecting Pancreatic Cancer in High-Risk Groups [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B026.
Abstract B027: A blood-based, multiplex protein biomarker signature shows superior performance in detection of early-stage pancreatic ductal adenocarcinoma (PDAC)
Authors: Palma Norma , Schiess Ralph , King Thomas , Athanasiou Alcibiade , Kureshi Natasha , Ford Lisa , Lucas Aimee , Katona Bryson , Brand Randall , Simeone Diane
Published: September 2024

BACKGROUND: A sensitive and specific blood biomarker test is needed to improve survival in PDAC through early detection. An initial discovery study analyzing more than 3000 proteins using both pre-selected immunoassays and the Olink proteomics platform identified 15 promising protein candidates, of which ten were successfully pre-verified for ELISA immunoassay analysis. This model-development study was conducted to develop and pre- validate a specific and sensitive biomarker signature for the early detection of PDAC. METHODS: This multicenter case-control study was performed using existing bio-banked pretreatment samples from patients with newly diagnosed PDAC (Stages I-II) and participants in PDAC high-risk surveillance programs as controls. Blinded quantitative measurement of protein biomarkers was performed using ELISA-based immunoassays. CA19-9 was measured on a Roche COBAS instrument. An AI-derived predictive mathematical biomarker signature incorporating multiple protein biomarkers was developed and assessed using standard cross- validation techniques. RESULTS: 128 Stage 1 and 2 PDACs and 495 high-risk control serum samples were analyzed with 10 predetermined biomarkers to develop a four-protein biomarker signature. The model predicted PDAC versus non-PDAC with 84% sensitivity at 98% specificity. Model performance was significantly better when compared to CA19-9 alone (sensitivity 65% at 98% specificity, p<0.001). In those patients with low CA19-9 (<37 U/ml), the model predicted PDAC with 62% sensitivity at 98% specificity, performing significantly better than CA19-9 alone (9% sensitivity at similar 98% specificity (p<0.001). Additionally, in patients >65 years old, the signature predicted PDAC with 90% sensitivity at 98% specificity, which was significantly more sensitive than CA19-9 alone (75% sensitivity at 98% specificity, p<0.001). Test accuracy was not affected by diabetes status. CONCLUSIONS: This blood-based, multiplexed biomarker signature showed high sensitivity and specificity and significantly outperformed CA19-9 for early-stage PDAC. This biomarker model has the potential to improve outcomes in PDAC patients through early detection. Analytical and clinical validation studies are planned.

Citation Format: Norma Palma, Ralph Schiess, Thomas King, Alcibiade Athanasiou, Natasha Kureshi, Lisa Ford, Aimee Lucas, Bryson Katona, Randall Brand, Diane Simeone. A blood-based, multiplex protein biomarker signature shows superior performance in detection of early-stage pancreatic ductal adenocarcinoma (PDAC) [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B027.
Abstract B029: Repurposing Digital PCR to Diagnose and Create a Novel Genomic Signature for Homologous Recombination Deficiency in Pancreatic Adenocarcinoma
Authors: Valerin Jennifer Brooke , Hasson Sophie , Rangel Valeria , Pannunzio Nicholas
Published: September 2024

Introduction: Germline mutations in DNA repair genes are often associated with increased risk of cancer. Mutations that affect the homologous recombination (HR) DNA repair pathway ( e.g., BRCA 1 and BRCA2) are known drivers of pancreatic adenocarcinoma. Early detection relies on identification of pathogenic mutations in patients with a family history of cancer. Next generation sequencing panels often use a select set of pathogenic variants for diagnosis, meaning that individuals with variants of uncertain significance may be missed, limiting testing of other family members for the potentially disease-causing variant. Here we describe a digital PCR assay developed to detect BRCA1 and BRCA2 variant that may eventually serve as a rapid, cost-effective alternative to sequencing that costs less than $5.00 per sample with results in 24 hours. This study highlights the need for better diagnostic tools, which will become critically important as we begin to study pathogenic mutations in more diverse populations. Methods: We have collected blood from 4 BRCA1 mutants and 5 BRCA2 mutants who have already undergone germline sequencing from commercially available assays. Clinicopathologic data has been collected as well. We designed two fluorescently labelled TaqMan probes, one that recognizes the wild-type BRCA alleles and one specific for mutant BRCA alleles. Briefly, 1 ng of genomic DNA is mixed with amplicon primers and fluorescent Taq-Man probes, then partitioned into 20,000 separate 517 picoliter wells. Quantification and detection are achieved based upon the fluorescent signal measured from each well. Results: We have successfully confirmed pathologic BRCA1 and BRCA2 mutations previously identified with next generation sequencing in 100% of samples analyzed. All three BRCA2 mutations generate a premature stop codon leading to a truncated protein and are known to be pathogenic. Two related patients have the same BRCA1 frameshift mutation that results in a premature stop codon, and one patient has a duplicated cytosine that leads to a frameshift mutation that is one of three characterized Ashkenazi Jewish founder mutations that increases cancer risk in this population . Conclusions: Here we report an innovative assay using digital PCR (dPCR) that provides a cost-effective, time-efficient method to identify MMR mutants and characterize VUS in patients and their families.

Citation Format: Jennifer Brooke Valerin, Sophie Hasson, Valeria Rangel, Nicholas Pannunzio. Repurposing Digital PCR to Diagnose and Create a Novel Genomic Signature for Homologous Recombination Deficiency in Pancreatic Adenocarcinoma [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B029.
Abstract B032: Evaluating T cell-inflammation in pancreatic neuroendocrine tumors
Authors: Romero Joan Miguel , Vafiadis James , Aalto Tess , Fang Ruomeng , Wang Yifan , Zogopoulos George
Published: September 2024

Background: Pancreatic neuroendocrine tumors (pNETs) are rare tumors arising from neuroendocrine cells in the pancreas. Their clinical behaviour and prognosis are variable and durable responses are often difficult to achieve with conventional therapies. Immunotherapy approaches may be efficacious in a subgroup of pNETs. In a recent study that did not include pNETs, we showed that a four-chemokine signature (c-Score: CCL4, CCL5, CXCL9, CXCL10) predicts T cell-inflammation and response to immune checkpoint inhibitors across cancers. We have hypothesized that the c-Score will also identify pNET subgroups with T cell-inflammation. Methods: The c-Score and hallmarks of the cancer-immunity cycle are being evaluated in pNETs as a cohort study (n=100 cases) of the Marathon of Hope Cancer Centres Network whole genome and transcriptome tumor sequencing (WGTS) project. The cohort study will compare pNET profiles with those of other pancreatic and peri-ampullary tumors. Results: As of June 1, 2024, primary tumor data from 23 cases were available for analysis, including 16 pNETs, 2 pancreatic ductal adenocarcinomas (PDAC), 2 pancreatic adenosquamous carcinoma (PASC), 2 distal cholangiocarcinomas (dCCA), and 1 ampullary carcinoma (AC). Dimension reduction by principle component analysis (PCA) revealed clustering based on histological subtype. Interestingly, PCA using immune genes also demonstrate subgrouping that overlapped with the histological subtypes, suggesting that immunity of pancreatic/peri-ampullary neoplasms may be directed by histological types rather than the pancreas gland itself. These cancers showed a broad distribution of c-Score expression, with pNETs having the lowest c-Score. Tumors with high expression of the c-Score, including 2 pNETs, had increased expression of cancer-immunity cycle gene sets. DUX4, FAM186A, and IGFN1 were amongst the most common genes mutated in all tumors. Conclusions: Early data suggest that pNETs generally harbor low c-Score values and hallmarks of cancer-immunity, with the existence of a subgroup of pNETs displaying T cell-inflammation.

Citation Format: Joan Miguel Romero, James Vafiadis, Tess Aalto, Ruomeng Fang, Yifan Wang, George Zogopoulos. Evaluating T cell-inflammation in pancreatic neuroendocrine tumors [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B032.
Abstract B033: MUC16 - Potential Target for Antibody-based Immunotherapy in Pancreatic Cancer
Authors: Brooks Cory L , Radhakrishnan Prakash
Published: September 2024

Pancreatic ductal adenocarcinoma (PDAC) is the most devastating and lethal cancer. PDAC patients with the current standard of care produce dismal overall survival benefits with high toxicities. Thus, there is an unmet clinical need to develop targeted therapeutics against PDAC. Approximately 50 to 70% of PDAC patients overexpress MUC16, which is associated with disease progression, metastasis, drug resistance, and poor patient survival. We demonstrated that MUC16 enhances PDAC tumor growth via binding and activating epidermal growth factor (EGF) receptor family members and its downstream target PI3K/AKT signaling pathways. Here, we show the efficacy of humanized anti-MUC16 antibody (huAR9.6) against MUC16-positive PDAC. Methods: We tested the in vitro efficacy of humanized anti-MUC16 antibody (huAR9.6) against MUC16+ PDAC cells, patient-derived xenografts (PDXs), and patient-derived organoids (PDOs). We evaluated the in vivo therapeutic efficacy of the huAR9.6 antibody in MUC16+ PDAC cells implanted in subcutaneous and orthotopic tumor models. Fucosylated and afucosylated huAR9.6 induced direct tumor-killing activity was evaluated by antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) with MUC16 positive PDAC cells. Results: Treatment with huAR9.6 reduced the in vitro growth, migration, invasion, and clonogenicity of MUC16+ PDAC cells and patient-derived organoids (PDOs). HuAR9.6 blocked MUC16-mediated ErbB and AKT activation in PDAC, PDOs, and PDX-derived cells. HuAR9.6 treatment induces ADCC and CDC against MUC16+ cells. Removing fucose residue on the N-glycans of the huAR9.6-IgG substantially increased huAR9.6’s ADCC activity. More importantly, huAR9.6 treatment caused PDAC regression in subcutaneous and orthotopic tumor models. Conclusion: The results of this study validate the translational therapeutic potential of huAR9.6 against MUC16-positive PDACs (detected in ∼ 50-70% of patients).

Citation Format: Cory L Brooks, Prakash Radhakrishnan. MUC16 - Potential Target for Antibody-based Immunotherapy in Pancreatic Cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B033.
Abstract B034: Myeloperoxidase limits tumor-associated neutrophils mediated immunosuppression in pancreatic cancer
Authors: Basnet Angisha , Boone Brain , Liu Tracy
Published: September 2024

Pancreatic ductal adenocarcinoma (PDAC) is a deadly disease with a survival rate under 12%. Treatments like immunotherapy and chemotherapy are ineffective in PDAC due to the immunosuppressive tumor microenvironment, in which tumor-associated neutrophils (TANs) are a major component. TAN immunosuppression has been shown to depend upon increased production of reactive oxygen species, with myeloperoxidase (MPO) being a major source of it. We investigated the contribution of MPO in mediating TAN immunosuppression using orthotopic PDAC models in wild-type and syngeneic MPO-deficient mice. We observed a significant delay in tumor growth and improved clinical scores when MPO was deficient. Additionally, treatment with the MPO-specific inhibitor Verdiperstat also delayed tumor growth. Flow cytometry analysis of the tumor microenvironment further confirmed a significant increase in CD8 T and NK cells, along with an increase in granzyme B level in both subsets, when MPO was deficient. Additionally, there was an increase in activation marker (CD25) and memory subset among both CD8 and CD4 T cells in MPO-deficient mice. Ex vivo studies with isolated TANs from tumor-bearing mice showed reduced CD8 T and NK cell suppression, and reactive oxygen species level in absence of MPO, supporting the contribution of MPO in TAN immunosuppression. These data suggest that loss of MPO in TANs has decreased immunosuppressive functions resulting in increased cytotoxic and activated T cells and NK cells with increased memory response within the tumor microenvironment. Our results demonstrate the contribution of MPO in regulating tumor progression, TAN immunosuppression, and immune cell infiltration using an orthotopic PDAC model.

Citation Format: Angisha Basnet, Brain Boone, Tracy Liu. Myeloperoxidase limits tumor-associated neutrophils mediated immunosuppression in pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B034.
Abstract B035: Nanoparticle delivery of innate immune agonists combines with senescence- inducing agents to mediate T cell control of pancreatic cancer
Authors: DeMarco Kelly D , Chibaya Loretah , Lusi Christina F , Kane Griffin I , Brassil Meghan L , Parikh Chaitanya N , Murphy Katherine C , Chowdury Shreya R , Li Junhui , Ma Boyang , Taylor Tiana E , Cerrutti Julia , Mori Haruka , Diaz-Infante Miranda , Peura Jessica , Pitarresi Jason R , Zhu Lihua Julie , Fitzgerald Katherine A , Atukorale Prabhani U , Ruscetti Marcus
Published: September 2024

Pancreatic ductal adenocarcinoma has quickly risen to become the 3rd leading cause of cancer- related death. This is in part due to its fibrotic tumor microenvironment (TME) that contributes to poor vascularization and immune infiltration and subsequent chemo- and immunotherapy failure. Here we investigated an innovative immunotherapy approach combining delivery of STING and TLR4 innate immune agonists via lipid-based nanoparticles (NPs) co-encapsulation with senescence-inducing RAS-targeted therapies that can remodel the immune suppressive PDAC TME through the senescence-associated secretory phenotype. Treatment of transplanted and autochthonous PDAC mouse models with these regimens led to enhanced uptake of NPs by multiple cell types in the PDAC TME, induction of type I interferon and other pro-inflammatory signaling, increased antigen presentation by tumor cells and antigen presenting cells, and subsequent activation of both innate and adaptive immune responses. This two-pronged approach produced potent T cell-driven and Type I interferon-mediated tumor regressions and long-term survival in preclinical PDAC models dependent on both tumor and host STING activation. STING and TLR4-mediated Type I interferon signaling were also associated with enhanced NK and CD8+ T cell immunity in human PDAC. Thus, combining localized immune agonist delivery with systemic tumor-targeted therapy can synergize to orchestrate a coordinated Type I interferon-driven innate and adaptive immune assault to overcome immune suppression and activate durable anti-tumor T cell responses against PDAC.

Citation Format: Kelly D DeMarco, Loretah Chibaya, Christina F Lusi, Griffin I Kane, Meghan L Brassil, Chaitanya N Parikh, Katherine C Murphy, Shreya R Chowdury, Junhui Li, Boyang Ma, Tiana E Taylor, Julia Cerrutti, Haruka Mori, Miranda Diaz-Infante, Jessica Peura, Jason R Pitarresi, Lihua Julie Zhu, Katherine A Fitzgerald, Prabhani U Atukorale, Marcus Ruscetti. Nanoparticle delivery of innate immune agonists combines with senescence- inducing agents to mediate T cell control of pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B035.
Abstract B037: Banana Lectin expressing CAR T cells to target Pancreatic Cancer
Authors: McKenna Katie , Ozcan Ada I , Markovitz David , Brenner Malcolm K
Published: September 2024

To overcome both the heterogenous and dynamic expression of tumor antigen expression in pancreatic ductal adenocarcinoma (PDAC) and the physical barrier provided by the associated fibrotic stroma, we have developed a novel therapy that recognizes and binds to distinct patterns of aberrant glycosylation specifically expressed on tumor cells and their surrounding stroma. Aberrant glycosylation patterns are a hallmark of cancer and are widely present on tumors including PDAC. We therefore incorporated H84T BanLec as part of a chimeric antigen receptor and co-expressed the construct in T cells and showed that H84T BanLec CAR expressing T-cells can effectively target pancreatic tumors. We hypothesized that our novel lectin CAR would enhance the activity of T cells when co-expressed with conventional scFV – derived CARs targeting tumor associated antigens We compared the activity of dual-expressing H84T/HER.2 CAR-T or H84T/PSMA CAR-T cells against single- expressing CARs targeting PDAC. We determined anti-tumor cytotoxicity by measuring residual GFP+ tumor cells in a sequential killing assay using flow cytometry. We observed superior anti-tumor activity using dual expressing CAR T cells compared to T cells expressing either HER.2- or H84T- or PSMA- CAR alone. Similarly, in 3D multicellular spheroids containing tumor and cancer-supportive stromal cells, an IncuCyte live imaging assay shows dual CAR T cells have greater cytotoxicity against PDAC than single CAR expressing T cells (p= 0.02 H84T/HER.2 vs HER.2 CAR; p=0.00003 H84T/PSMA CAR vs PSMA CAR). These results also translate to improved anti- tumor function of dual CAR T cells in PDAC xenograft in vivo models where H84T/HER.2 CAR T cells significantly reduced the tumor volume burden (p=0.015; H84T/HER.2 average=57.1mm3; HER.2 average=116.1mm3; H84T average=130.3mm3). These findings suggest that H84T BanLec CAR T cells provide a tool to target the aberrant glycosylation patterns of malignant cells and their supporting stroma and may contribute to an effective treatment option for PDAC patients. We are now elucidating the underlying mechanism by which H84T BanLec CARs enhance tumor activity and promote T cell infiltration.

Citation Format: Katie McKenna, Ada I Ozcan, David Markovitz, Malcolm K Brenner. Banana Lectin expressing CAR T cells to target Pancreatic Cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B037.
Abstract B038: Tumor Derived Parathyroid Hormone Related Protein is an Orchestrator of Immunosuppression in Pancreatic Cancer
Authors: Johnson Calvin , Pitarresi Jason
Published: September 2024

Pancreatic ductal adenocarcinoma (PDAC) has the lowest 5-year survival of common cancers, owing to a lack of early detection and ineffective therapies. Immune checkpoint inhibitors hold promise for PDAC patients, and while they represent the most ongoing clinical trials, they have had little success. Parathyroid Hormone Related Protein (PTHrP; encoded by PTHLH) defines the most aggressive squamous/basal/quasi-mesenchymal PDAC subtype. Our previous work revealed autocrine PTHrP signaling mediates tumor growth, epithelial-to-mesenchymal transition (EMT), and metastasis. However, PTHrP’s relationship with immune cells of the tumor microenvironment (TME) remains unknown. Investigation of tumors from KrasG12D; p53R172H; Pdx1-Cre; YFP (KPCY) and KPCY-Pthlh loxP/WT (KPCY-Pthlhhet) mice revealed less tumor associated neutrophils (TANs) and greater cytotoxic T cell infiltration, demonstrating the necessity of PTHrP for immune exclusion. Orthotopic implantation of Pthlh overexpressing KPCY cells (KPCY-PthlhOE) revealed a greater proportion of TANs than the control. A concomitant decrease in the number of effector T and natural killer cells in the KPCY-PthlhOE tumors was observed, showing PTHrP is sufficient to organize an immunosuppressive TME. Interestingly, recombinant human PTHrP was sufficient to induce TANs mobilization in vivo. To interrogate the mechanism of neutrophil trafficking into the TME, cytokine production was quantified in vitro. KPCY-PthlhOE exhibited a pronounced increase of Cxcl1 expression, a strong neutrophil chemokine, leading us to believe neutrophils migrate to the TME using a Cxcl1 gradient. Therefore, we hypothesized that PTHrP-mobilized neutrophils express the receptor for CXCL1; CXCR2. Indeed, recombinant PTHrP was sufficient to mobilize Cxcr2+ neutrophils in vivo. Furthermore, recombinant PTHrP was able to induce Cxcl1 production by KPCY tumor cells in vitro in a cAMP response element-binding protein(CREB)-dependent manner. These data describe a novel mechanism for the mobilization and infiltration of immune suppressive TANs into the TME, initiated by PTHrP. The PTHrP-dependent immunosuppressive TME excludes and inhibits effector immune cells. Further interrogation of PTHrP signaling during the genesis of the immune suppressive TME in PDAC may lead to the development of therapeutics to meet this unmet clinical need.

Citation Format: Calvin Johnson, Jason Pitarresi. Tumor Derived Parathyroid Hormone Related Protein is an Orchestrator of Immunosuppression in Pancreatic Cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B038.
Abstract B040: B cells facilitate lymph node colonization in pancreatic ductal adenocarcinoma
Authors: Bertocchi Alice , Hoffman Megan T , Qiang Li , Morell Massiel , Hsu Lauren L , Dougan Michael L , Agudo Judith , Dougan Stephanie K
Published: September 2024

Pancreatic ductal adenocarcinoma (PDAC) carries a low survival rate. Several factors contribute to its dismal prognosis, including resistance to available therapies and high invasiveness. Lymph nodes act as an early systemic source of circulating malignant cells, allowing their dissemination to other organs early in disease progression. Lymphatic colonization is linked to worse prognosis, and a better understanding of mechanisms regulating lymph node metastasis is clinically needed. To study each step in the metastatic cascade to the lymph nodes, we have developed a mouse co-clinical model of resectable pancreatic cancer. This model mimics the frequency of human PDAC metastatic recurrence, on a similar time scale relative to the lifespans of mice and humans and allows us to investigate very early events in the metastatic cascade. In contrast to the established anti-tumor role of T cells, the role of B cells in cancer immunology is more complex. B cells are a predominant immune population in lymph nodes, but their role in relation to lymph node colonization has never been fully addressed. Using our model of PDAC spontaneous metastasis and a mouse model of B cell depletion, we showed that lymph node metastasis does not form in the absence of B cells. We demonstrated that B cells, but not secreted antibodies, are required for successful lymph node colonization. We also gained evidence that B cells are orchestrating a complex interplay between disseminated cancer cells and other immune cells in the draining lymph node. Particularly, T cells seem to be involved in preventing cancer cell from growing into macro-metastasis only in the absence of B cells. We are now investigating the mechanisms employed by B cells to facilitate this cellular network to facilitate lymph node colonization in PDAC. The ultimate outcome of our work will be the design of effective immune strategies to prevent and treat lymph node dissemination of such a deadly disease.

Citation Format: Alice Bertocchi, Megan T Hoffman, Li Qiang, Massiel Morell, Lauren L Hsu, Michael L Dougan, Judith Agudo, Stephanie K Dougan. B cells facilitate lymph node colonization in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B040.
Abstract B041: Fibroblast STAT3 Signaling in Pancreatic Cancer: Implications for Immunotherapy and Tumor Microenvironment Modulation
Authors: Saberi Samaneh , Bumbleburg Cameron , Everett Caroline , Lefler Julia E , Jordan Victoria , Han Lu , Sharma Sudarshana , Ostrowski Michael C.
Published: September 2024

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer distinguished by a dense stromal microenvironment. The current investigation delves into the fibroblast-specific STAT3 signaling in the PDAC tumor microenvironment (TME) and its effects on immune cell infiltration and extracellular matrix (ECM) modulation. An association was identified between heightened levels of phosphorylated STAT3 (pSTAT3) in tumor-associated fibroblasts (CAFs) and a more unfavorable prognosis, particularly among male patients. Comparative analysis of gene expression patterns in normal fibroblasts and those deficient in STAT3, extracted from mouse models of pancreatic cancer, unveiled distinct gene expression profiles related to the inflammatory signaling pathway (IL6, ADM, CXCL11, CD80, VEGFA, TGFB1, STC1, STC2). Utilizing ChIP-Seq analysis with an anti-pSTAT3 antibody, it was confirmed that STAT3 binds to the regulatory regions of these genes, supporting its regulatory role in the inflammatory signaling pathway. Moreover, the absence of STAT3 in CAFs resulted in a decline in M2 macrophages and an upsurge in M1 macrophages within the TME, indicating a potential function of STAT3 in influencing macrophage polarization. Noteworthy observations also revealed that STAT3 signaling in CAFs impacts ECM remodeling, as illustrated by reduced collagen deposition. Furthermore, the deficiency of STAT3 in CAFs led to a notable reduction in the quantity of neutrophils within the TME in our mouse model. Additionally, a plausible involvement of STAT3 in neutrophil recruitment and activation through the CXCL1/CXCR2 axis was indicated. Alterations in the infiltration of neutrophils and macrophages due to the absence of STAT3 could profoundly influence the immune response against PDAC. The modified composition of ECM following STAT3 deletion might also impact the infiltration and functioning of immune cells. These outcomes underscore the significance of STAT3 signaling in CAFs as a promising therapeutic target in PDAC, offering potential for modulating the tumor microenvironment, augmenting anti-tumor immunity, and advancing patient outcomes.

Citation Format: Samaneh Saberi, Cameron Bumbleburg, Caroline Everett, Julia E Lefler, Victoria Jordan, Lu Han, Sudarshana Sharma, Michael C. Ostrowski. Fibroblast STAT3 Signaling in Pancreatic Cancer: Implications for Immunotherapy and Tumor Microenvironment Modulation [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B041.
Abstract B047: Antigenic properties determine the outcome of B cell driven anti-tumor immunity
Authors: Sturdevant Colleen , Kren Nancy , Silva Harrison , Gomez Ismael , Hepperla Austin , Pylayeva-Gupta Yuliya
Published: September 2024

B cells have the capacity to elicit both anti- and pro-tumorigenic effects; yet the determinants of productive B cell responses in cancer remain elusive. Using a system where a B cell neoantigen is either soluble or tethered to the surface of pancreatic cancer cells, we demonstrate that membrane-tethered antigen is sufficient to elicit activation of anti-tumor immunity and reduce tumor growth in an NK cell-dependent manner. We also show that decreased antigen affinity to the BCR promotes regulatory B cell function which can be overcome by increased avidity of membrane-tethered antigen. Furthermore, soluble and membrane-tethered antigens drive qualitatively distinct germinal center, plasma cell, memory B cell, and Treg responses. Finally, we describe two classes of membrane-associated antigens that correlate with GC B cell signature and improved survival in pancreatic cancer patients. Thus, antigen localization impacts basic mechanisms governing B cell differentiation and the resulting immune response to solid malignancy with implications for vaccine engineering.

Citation Format: Colleen Sturdevant, Nancy Kren, Harrison Silva, Ismael Gomez, Austin Hepperla, Yuliya Pylayeva-Gupta. Antigenic properties determine the outcome of B cell driven anti-tumor immunity [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B047.
Abstract B057: The circadian master regulator BMAL1 blocks immune cell recognition of pancreatic ductal adenocarcinomas via tumor-derived interleukin-1 receptor antagonist
Authors: Prela Orjola , Wang Lan , Harris Chris , Carpizo Darren
Published: September 2024

Many tumor types, including pancreatic adenocarcinomas, have dysregulated circadian rhythms. Previous work in our lab has shown that disseminated dormant tumor cells have increased expression of Dec2, a circadian rhythm gene, and knocking out Dec2 leads to increased overall survival in our murine resectable PDAC model. To see whether the effect of Dec2 is due to a circadian effect, we deleted the master regulator circadian gene, BMAL1. Using CRISPR-generated knockout (KO) cell lines, we saw that loss of Bmal1 completely abrogated metastasis in immunocompetent mice, but not in immunocompromised mice indicating an immune mediated mechanism. Similarly in our murine resectable PDAC model, loss of BMAL1 led to an increase in overall survival in immunocompetent mice only. Looking at the tumor microenvironment, we saw an increase in CD4+ and CD8+ T cell infiltration in the tumors derived from the BMAL KO cells. We then evaluated the BMAL KO cells for their cytokine secretion and saw that loss of BMAL1 led to decreased interleukin-1 receptor antagonist both in vitro and in vivo. IL-Ra has been shown in literature to suppress the immunogenic anti-tumor response by impairing the activities of APCs, CD4+ and CD8+ T cells and disruption of IL-1Ra can reverse the TME towards more immunogenic leading to an antitumor effect. Taken together these studies implicate Bmal1 in regulating anti-tumor immunity in PDAC through its regulation of IL-1Ra secretion. This is a novel function for a circadian rhythm gene in PDAC biology.

Citation Format: Orjola Prela, Lan Wang, Chris Harris, Darren Carpizo. The circadian master regulator BMAL1 blocks immune cell recognition of pancreatic ductal adenocarcinomas via tumor-derived interleukin-1 receptor antagonist [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B057.
Abstract B060: Unveiling resistance mechanisms to CAR T-cell therapy in pancreatic cancer through in vivo CRISPR/Cas9 knockout screening
Authors: Fröse Julia , Whittaker Charlie , Leclerc Paul , Langenbucher Adam , Hellinger Riley , Goulet Daniel R. , Hemann Michael T.
Published: September 2024

Pancreatic ductal adenocarcinoma (PDAC) is projected to become the second leading cause of cancer death by 2030. PDAC lacks effective treatment options and innovative strategies for therapeutic intervention are urgently needed. Chimeric Antigen Receptor (CAR)-T cell therapy has shown remarkable success in treating hematologic malignancies, yet achieving efficacy in solid tumors remains a significant challenge. Early results from clinical trials show limited efficacy of CAR T-cell therapy in PDAC. To uncover tumor-intrinsic mechanisms of resistance to CAR T-cell therapy in vivo, we performed iterative CRISPR/Cas9-based pooled screens in a fully immunocompetent, orthotopic model of PDAC. We identified a variety of genes influencing CAR T-cell treatment efficacy. In particular, loss of genes involved in redox biology and oxidative stress sensitized PDAC tumors to CAR T-cell therapy in vivo. Additionally, single-cell RNA sequencing of PDAC tumors subjected to CAR T-cell therapy unveiled a distinct subset of tumor cells resilient to the treatment, characterized by changes in oxidative stress. Our findings indicate a potential avenue for therapeutic synergy by targeting pathways involved in oxidative stress to increase the efficacy of CAR T cell therapy in PDAC.

Citation Format: Julia Fröse, Charlie Whittaker, Paul Leclerc, Adam Langenbucher, Riley Hellinger, Daniel R. Goulet, Michael T. Hemann. Unveiling resistance mechanisms to CAR T-cell therapy in pancreatic cancer through in vivo CRISPR/Cas9 knockout screening [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B060.
Abstract B064: Antigen-presenting type-I conventional dendritic cells facilitate curative checkpoint blockade immunotherapy in pancreatic cancer
Authors: Mahadevan Krishnan K , Dyevoich Allison M. , Chen Yang , Li Bingrui , Sugimoto Hikaru , Sockwell Amari , McAndrews Kathleen , Wang Huamin , Shalapour Shabnam , Watowich Stephanie , Kalluri Raghu
Published: September 2024

The link between cancers and inflammation was first made by Rudolph Virchow more than a century ago when cancers were observed at sites with chronic inflammation. The host response to cancer shares many parallels with inflammation and wound healing process.Inflammation and tissue damage associated with pancreatitis can precede or occur concurrently with pancreatic ductal adenocarcinoma (PDAC). We demonstrate that in PDAC coupled with pancreatitis (ptPDAC), antigen-presenting type-I conventional dendritic cells (cDC1s) are specifically activated. Immune checkpoint blockade therapy (iCBT) leads to cytotoxic CD8+ T cell activation and eradication of ptPDAC with restoration of lifespan even upon PDAC re-challenge. Such eradication of ptPDAC was reversed following specific depletion of dendritic cells. Employing PDAC antigen-loaded cDC1s as a vaccine, immunotherapy-resistant PDAC was rendered sensitive to iCBT with a curative outcome. Analysis of the T-cell receptor (TCR) sequences in the tumor infiltrating CD8+ T cells following cDC1 vaccination coupled with iCBT identified unique CDR3 sequences with potential therapeutic significance. Our findings identify a fundamental difference in the immune microenvironment and adaptive immune response in PDAC concurrent with, or without pancreatitis, and provides a rationale for combining cDC1 vaccination with iCBT as a potential treatment option.

Citation Format: Krishnan K Mahadevan, Allison M. Dyevoich, Yang Chen, Bingrui Li, Hikaru Sugimoto, Amari Sockwell, Kathleen McAndrews, Huamin Wang, Shabnam Shalapour, Stephanie Watowich, Raghu Kalluri. Antigen-presenting type-I conventional dendritic cells facilitate curative checkpoint blockade immunotherapy in pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B064.
Abstract B065: Eosinophils alter metastatic spread in pancreatic cancer
Authors: Hoffman Megan T , Lenehan Patrick J , Bertocchi Alice , Wang Jen , Ali Lestat , Qiang Li , Uchida Amiko , Vayrynen Sara , Costa Andressa Dias , Dougan Michael , Heckler Max , Nowak Jonathan , Wolpin Brian W , Dougan Stephanie K
Published: September 2024

Pancreatic ductal adenocarcinoma (PDA) is the third most common cause of cancer death in the US with a 11% 5-year survival rate. A key contributor of this dismal prognosis is early and frequent metastatic spread with limited treatment options for patients. Metastasis in PDA is facilitated by a robust fibroinflammatory response in the primary tumor site, a large portion of which is composed of infiltrating immune cells, and survival during transit to establish in the secondary site. In the primary tumor reactive stroma, we found increased eosinophils in both human and mouse PDA compared to the normal pancreas. Eosinophils are an innate immune cell best known for their ability to control parasite responses and have been implicated in either pro- or anti-cancer roles in various solid tumors. We used the ΔdblGata mice, which lack eosinophils, to study the role of eosinophils during metastatic spread using a resectable model of PDA metastasis. This model of metastasis was developed to facilitate consistent seeding of lung metastasis in approximately 50 percent of mice from a transient subcutaneous tumor which undergoes subsequent surgical removal and harvest to evaluate metastasis at 4 weeks. We found that mice lacking eosinophils have increased metastasis to the lung in our resectable model of PDA metastasis but no difference in establishment of IV injected PDA tumor cells, suggesting eosinophil control at the primary tumor site. Single cell sequencing of the subcutaneous tumors finds no difference in the immune cell compartment but alterations in the EMT states of the tumor cells. Staining confirms a decreased level of E-cadherin with unchanged vimentin and zeb1 suggesting a partial EMT state in eosinophil knockout mice. We conclude that eosinophils in PDA inhibit the metastatic process, in part, through control of tumor cell state.

Citation Format: Megan T Hoffman, Patrick J Lenehan, Alice Bertocchi, Jen Wang, Lestat Ali, Li Qiang, Amiko Uchida, Sara Vayrynen, Andressa Dias Costa, Michael Dougan, Max Heckler, Jonathan Nowak, Brian W Wolpin, Stephanie K Dougan. Eosinophils alter metastatic spread in pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B065.