bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract LB006: In vivo programming of myeloid cells by mRNA mediated delivery of novel Fc alpha fusion receptor activates anti-tumor immunity
Authors: Zhao Hongyun , Shcherbakova Inna , Prod’homme Thomas , McCreedy Bruce , Wang Yuxiao , Getts Daniel
Published: June 2022

Immunotherapy has revolutionized cancer treatment. However, for the majority of patients with advanced solid tumors, sustained clinical benefit has yet to be achieved. Myeloid cells such as monocytes and macrophages readily accumulate in tumors, in some cases contributing up to 75% of the tumor mass. Reprogramming circulating and tumor associated myeloid cells to activate their ability to elicit anti-tumor adaptive immunity by phagocytosis, cytokine secretion and antigen presentation is an attractive approach to harness and orchestrate systemic anti-tumor immunity. It remains challenging to specifically target and activate myeloid cells in vivo. To overcome this hurdle, we have developed a novel in vivo myeloid cell engineering platform: Fc-alpha Receptor Fusion Constructs. Unlike other chimeric antigen receptors (CARs) the construct was engineered by fusing a tumor recognition scFv with the alpha chain of human Fc receptors. The stable expression and function of these receptors requires endogenously expressed Fc receptor gamma chain, a protein with limited expression to immune cells, mostly myeloid cells. Here, we present that intravenous infusion of lipid-nanoparticle (LNP) encapsulating the Fc-alpha Receptor Fusion Construct mRNA results in the uptake and expression of the construct by myeloid cells. In immunodeficient xenograft models of hepatocellular carcinoma and triple negative breast cancer, delivery of LNP mRNA encoding for GPC3 or TROP2 targeted Fc-alpha Receptor Fusion Constructs resulted in tumor killing, confirming the ability of this approach to program myeloid cells. Furthermore, in the B16 syngeneic melanoma model, treatment with the melanoma antigen GP75 targeted Fc-alpha Receptor Fusion Constructs was also associated with the initiation of broad systemic immune responses, characterized by tumoral accumulation of activated CD8+ T cells, reduced tumor associated Tregs and activation of antigen presenting cells in spleen. Together these studies highlight the potential of Fc-alpha Receptor Fusion Construct delivered directly in vivo to program myeloid cells to recognize and kill cancer.

Citation Format: Hongyun Zhao, Inna Shcherbakova, Thomas Prod’homme, Bruce McCreedy, Yuxiao Wang, Daniel Getts. In vivo programming of myeloid cells by mRNA mediated delivery of novel Fc alpha fusion receptor activates anti-tumor immunity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB006.
Abstract LB008: Characterization of immune correlates of clinical activity for Nous-209, an off-the-shelf immunotherapy, with pembrolizumab for treatment of tumors characterized by microsatellite instability (MSI)
Authors: D'Alise Anna Morena , Leoni Guido , Langone Francesca , Micarelli Elisa , Cotugno Gabriella , Overman Michael James , Fakih Marwan , Le Dung , Faivre Théa , Scarselli Elisa
Published: June 2022

Tumors with microsatellite instability (MSI) are caused by a deficiency in DNA mismatch repair (dMMR) system that leads to the accumulation of mutations within microsatellite regions. These types of mutations can determine a shift of the translational reading frame, generating Frame Shifted Peptides (FSPs). FSPs are tumor-specific neoantigens. Nous-209 is an off-the-shelf vaccine encoding 209 FSPs shared across dMMR/MSI tumors (Leoni et al., Cancer Res, 2020). The combination of the Nous-209 genetic polyvalent cancer vaccine and pembrolizumab has been demonstrated to be safe, highly immunogenic, with promising early signs of clinical efficacy in 12 patients with 7 durable confirmed PRs, 2 durable SDs and 3 PDs observed (Overman et al., SITC Nov 13, 2021 Poster number: 410). Here, we explore immune correlates potentially associated with the clinical outcome with the aim to address the Nous-209 contribution to the activity of pembrolizumab in this patient population. Several immunological analyses were performed on biological samples collected before and after treatment with Nous-209. Analyses were performed on paired blood and tumor biopsy samples. In periphery, vaccine immunogenicity was demonstrated by ex-vivo interferon-gamma ELISpot assay in 67% of subjects in dose level 1 (n=3), and 100% (n=7) of patients in dose level 2 with a mean of ≈1,500 IFN-γ SFCs/million PBMCs at the peak of the immune response. In 3 patients with partial response whose pre/post tumor biopsies were available, the intratumoral TCR repertoire was expanded and diversified post treatment with Nous-209. Moreover, in one out of these three patients it was possible to track vaccine-induced neoantigen specific TCR in the tumor biopsy post Nous-209 treatment. Overall, these results indicate that neoantigen specific CD8+ T cells, induced by Nous-209, expand and diversify upon treatment, and successfully traffic to and infiltrate the tumor microenvironment to exert anti-tumor activity.

Citation Format: Anna Morena D'Alise, Guido Leoni, Francesca Langone, Elisa Micarelli, Gabriella Cotugno, Michael James Overman, Marwan Fakih, Dung Le, Théa Faivre, Elisa Scarselli. Characterization of immune correlates of clinical activity for Nous-209, an off-the-shelf immunotherapy, with pembrolizumab for treatment of tumors characterized by microsatellite instability (MSI) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB008.
Abstract LB022: A hybrid epithelial to mesenchymal transition in ex-vivo cutaneous squamous cell carcinoma tissues
Authors: Pulford Christopher S. , Uppalapati Chandana K. , Montgomery McKale R. , Hull Elizabeth E. , Leyva Kathryn J.
Published: June 2022

While most cases of cutaneous squamous cell carcinoma (cSCC) are benign, invasive cSCC is associated with higher mortality and is often more difficult to treat. As such, understanding the factors that influence the progression of cSCC are important. Aggressive cancers metastasize through a series of evolutionary changes, collectively called the epithelial-to-mesenchymal transition (EMT). During EMT, epithelial cells transition to a highly mobile mesenchymal cell type with metastatic capacities. While changes in expression of TGF-β, vimentin, and E-cadherin are hallmarks, EMT is not an “all or none” process. Using patient-derived cSCC and adjacent normal tissues (ANT), we observed a significant increase in mRNA expression of TGF-β (p<0.05), TGF-βR2 (p<0.001), and E-cadherin (p<0.005) in cSCC tissues by qPCR. Immunoblots performed on homogenized tissues yielded significant and parallel increases in protein expression of TGF-β (p<0.05) and E-cadherin (p<0.05). We also observed increased expression of the EMT-associated transcription factors Zeb1 and Snai1 in cSCC tissue sections using immunohistochemistry. Interestingly, we observed a significant increase in expression of vimentin (p<0.01) by immunoblot and differential expression of four oncogenic and EMT-associated miRNAs; miR-31 expression was significantly higher in cSCC tissues (p<0.001), while we observed a significant decrease in expression of miR-34a (p<0.05), miR-200b, and miR-200c in cSCC tissues. Examination of ANT and cSCC tissue sections using immunofluorescence and immunohistochemistry showed differential, and reverse, expression of E-cadherin and vimentin among cells within an individual tumor. Collectively, our data support a hypothesis that cSCC tumors are undergoing a hybrid EMT program, where there is variation in expression of EMT markers by cells within a tumor mass that may be facilitating invasion. This hybrid EMT program may be promoting both survival and invasiveness of the tumors. A better understanding of this hybrid EMT process may influence therapeutic strategies in more invasive disease.

Citation Format: Christopher S. Pulford, Chandana K. Uppalapati, McKale R. Montgomery, Elizabeth E. Hull, Kathryn J. Leyva. A hybrid epithelial to mesenchymal transition in ex-vivo cutaneous squamous cell carcinoma tissues [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB022.
Abstract LB029: Comprehensive structure-function evaluation of the SHOC2 holophosphatase reveals disease mechanisms and therapeutic opportunities
Authors: Kwon Jason , Hajian Behnoush , Bian Yuemin , Amor Alvaro , Fuller James , Fraley Cara , Baker Laura , So Jonathan , Mayhew David , Sykes Abbey , Persky Nicole , Yang Xiaoping , Root David , Perry Charles , Lemke Christopher , Hahn William , Aguirre Andrew
Published: June 2022

Receptor tyrosine kinase (RTK)-RAS signaling through the downstream mitogen activated protein kinase (MAPK) cascade regulate cell proliferation and survival. The SHOC2 holophosphatase functions as a key regulator of RTK-RAS signaling by removing an inhibitory phosphorylation on RAF family proteins to potentiate MAPK signaling. SHOC2 forms a ternary complex with MRAS and PP1C, and human germline gain-of-function mutations of this complex result in congenital RASopathy syndromes. However, the structure and the assembly of this complex are poorly understood. Here, we use cryogenic electron microscopy (cryo-EM) to resolve the structure of the SHOC2-PP1C-MRAS holophosphatase to 2.9Å resolution. Furthermore, we define the biophysical principles of SHOC2 holoenzyme interactions, elucidate the assembly order of the complex, and systematically interrogate the functional consequences of nearly all possible missense variants of SHOC2 through deep mutational scanning. We demonstrate that SHOC2 binds PP1C and MRAS through a concave surface created by the leucine-rich repeat region and further engages PP1C through the N-terminal disordered region containing a degenerate RVxF motif. Initial complex formation is mediated by SHOC2-PP1C interactions and is stabilized by binding of GTP-loaded MRAS. These observations define how clinical mutants in Noonan-like syndrome and cancer stabilize interactions of complex members to enhance holophosphatase activity. Together, this integrative structure-function model comprehensively defines key binding interactions within the SHOC2 holophosphatase, informing therapeutic development.

Citation Format: Jason Kwon, Behnoush Hajian, Yuemin Bian, Alvaro Amor, James Fuller, Cara Fraley, Laura Baker, Jonathan So, David Mayhew, Abbey Sykes, Nicole Persky, Xiaoping Yang, David Root, Charles Perry, Christopher Lemke, William Hahn, Andrew Aguirre. Comprehensive structure-function evaluation of the SHOC2 holophosphatase reveals disease mechanisms and therapeutic opportunities [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB029.
Abstract LB034: Evaluation of a novel single-cell RNA sequencing methodology for use in clinical trial settings
Authors: Corney David , Han Yang , Qiu Yu , Fan Yongjun , Stephens Michael , O'Hara Andrea , Turner Laure , Mozdzierz Christopher , Latif Haythem , Zhou Ginger
Published: June 2022

Bulk RNA sequencing (RNA-seq) is regularly employed for transcriptional profiling but provides only a snapshot of the average population. Particularly when studying disease, understanding differences in diverse cells is essential thus single-cell resolution is a necessity due to significant cellular heterogeneity. High-throughput droplet- and microfluidic-based approaches for performing single-cell RNA-seq (scRNA-seq) are invaluable techniques for uncovering changes in cells such as differential gene expression and epigenetic states in cancer research. A challenge for scRNA-seq, however, is sample preparation as typically tissues must be processed immediately after collection. We and others have reported alternative approaches to stabilize samples prior to analysis such as cryopreservation of cells and tissues and methanol-based fixation of cells. However, the inclusion of these approaches is still limited in many settings due to the challenging logistics involved in sample collection. To further broaden the ability of researchers to deploy scRNA-seq, we report our experiences from testing a pre-commercial workflow developed by 10x Genomics to resolve these sample management limitations. The use of paraformaldehyde (PFA) to fix samples at the collection site allows samples to be transported to remote laboratories for downstream processing without sacrificing integrity or data quality. This advance has enabled new possibilities for sample accessibility, throughput, and batched analysis in basic and translational research settings. Furthermore, this approach also allows for analysis of transcriptome-wide gene expression at high sensitivity with simultaneous cellular readouts. Here we report a case study comparing the PFA method to standard approaches, and highlight advantages and potential applications previously not possible with reported sample preparation strategies.

Citation Format: David Corney, Yang Han, Yu Qiu, Yongjun Fan, Michael Stephens, Andrea O'Hara, Laure Turner, Christopher Mozdzierz, Haythem Latif, Ginger Zhou. Evaluation of a novel single-cell RNA sequencing methodology for use in clinical trial settings [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB034.
Abstract LB041: Differential response to progranulin in proliferative and metastatic SW13 cell subtypes
Authors: Okonya Chika , Montgomery McKale R. , Pascual Agnes S. , Uppalapati Chandana , Leyva Kathryn J. , Hull Elizabeth E.
Published: June 2022

The SW13 human adrenocortical carcinoma line exists in proliferative SW13- and metastatic SW13+ subtypes which interconvert by epigenetic mechanisms in an epithelial to mesenchymal transition (EMT) process. This work investigates the contribution of progranulin to the maintenance of and conversion between the SW13 subtypes. A prognostic biomarker in cancer, progranulin is a pleotropic signaling molecule composed of 7 highly conserved granulin repeats. Each granulin unit has independent and sometimes opposing activity in the regulation of diverse cellular activities including proliferation, chemoresistance, lysosomal function, migration, wound healing, and inflammation. Thus, the ultimate biological activity of progranulin is context-dependent as it relies on the expression of diverse intracellular and extracellular proteases. Treatment with exogenous progranulin increases growth of SW13- cells but not SW13+ cells, a finding which suggests differential processing. As the metastatic SW13+ subtype produces more progranulin than the SW13- subtype, these data are consistent with an inability of SW13+ to process endogenous progranulin to the mitogenic granulin unit(s). Immunoblotting with antibodies specific for granulin repeats indicates that progranulin is processed differently in each subtype. In this work, we focused on lysosomes as a potential site for differential processing of progranulin for several reasons. First, lysosomes play a role in EMT. Second, lysosomal proteases have been shown to process progranulin and progranulin itself plays a role in lysosome maturation. Finally, preliminary data suggest that there are differences in lysosomal function and pH between the two subtypes. Ongoing experiments address the benefits of lysosomal acidification and the role that differential processing of progranulin may play on the maintenance and interconversion of the SW13 subtypes.

Citation Format: Chika Okonya, McKale R. Montgomery, Agnes S. Pascual, Chandana Uppalapati, Kathryn J. Leyva, Elizabeth E. Hull. Differential response to progranulin in proliferative and metastatic SW13 cell subtypes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB041.
Abstract LB042: Sorting nexin-dependent therapeutic targeting of oncogenic epidermal growth factor receptor
Authors: Atwell Ben
Published: June 2022

Overexpression and/or overactivation of the Epidermal Growth Factor Receptor (EGFR) is oncogenic in several tumor types yet targeting the kinase domain of wildtype EGFR has had limited success. EGFR has numerous kinase-independent roles, one of which is accomplished through the Sorting Nexin-dependent retrotranslocation of EGFR to the nucleus, which is observed in some metastatic cancers and therapeutically resistant disease. Here, we have utilized the BAR domain of Sorting Nexin 1 to create a peptide-based therapeutic (cSNX1.3) that promotes cell death in EGFR-expressing cancer. We evaluated the efficacy of cSNX1.3 in tumor-bearing WAP-TGFα transgenic mice (an EGFR-dependent model of breast cancer), where cSNX1.3 treatment resulted in significant tumor regression without observable toxicity. Evaluation of remaining tumor tissues found evidence of increased PARP cleavage, suggesting apoptotic tumor cell death. To evaluate the mechanism of action for cSNX1.3, we found that cSNX1.3 binds the C-terminus of the EGFR kinase domain at an interface site opposite the ATP binding domain with a K d of ~4.0 µM. In vitro analysis found that cSNX1.3 inhibits both long-term EGF-dependent AKT and ERK activation, as well as nuclear localization of EGFR. To determine specificity, we evaluated cancer cell lines expressing wildtype EGFR (MDA-MB-468, BT20 and A549), mutant EGFR (H1975) and non-transformed lines (CHO and MCF10A). Only transformed lines expressing wildtype EGFR responded to cSNX1.3, while mutant EGFR and normal cells responded better to the EGFR kinase inhibitor (Sapitinib). Phenotypically, cSNX1.3 inhibits EGF-, NRG-, and HGF-dependent migration, but not HA-dependent migration. Together, these data indicate that targeting retrotranslocation of EGFR may be a potent therapeutic for RTK-active cancer.

Citation Format: Ben Atwell. Sorting nexin-dependent therapeutic targeting of oncogenic epidermal growth factor receptor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB042.
Abstract LB103: Novel DNA-based-T-cell-activation for the generation of chimeric antigen receptor T cells with enhanced anti-leukemia cytotoxicity
Authors: Benzaoui Mehdi , Achar Sooraj R. , Keskar Vandana , Sood Anup , Davis Brian M. , Highfill Steven L. , Altan-Bonnet Grégoire , Chien Christopher D. , Taylor Naomi
Published: June 2022

Chimeric antigen receptor (CAR)-T cell therapy has shown remarkable results in the treatment of hematological malignancies. However, several challenges remain, including achieving predictable efficacy and safety profiles and extending this approach to solid tumors. As such, the development of approaches that generate engineered T cells with superior persistence and efficacy are needed. Currently, the generation of CAR-T requires that they be activated and expanded ex vivo, generally via beads coated with anti-CD3/anti-CD28 mAbs. T cell activation provides three fundamental signals; (i) primary triggering of TCR signals; (ii) secondary co-stimulatory signals and, (iii) synthesis of cytokines to direct T cell expansion and differentiation. We hypothesize that a CAR-T response can be modulated by tuning the: (i) pattern, (ii) magnitude and, (iii) duration of the input T cell activation signals. To this end, we used a novel, soluble, tunable activation platform based on DNA hybridization - utilizing concatenated single stranded DNA (ssDNA) polymers to cluster complementary oligonucleotide-modified antibodies targeted at T-cell surface receptors. This DNA-Based-T-cell-Activation (DBTA) platform was compared with conventional bead-bound CD3/CD28 antibodies (Dynabead) in the generation and function of T cells engineered to express a CD19-targeted CAR harboring a 4-1BB co-stimulatory domain. The two methods did not result in any significant differences in CAR-T expansion nor in memory/activation phenotypes. Notably, though, these cells exhibited higher cytokine secretion in response to CAR stimulation, and in vitro killing of DBTA-generated CART was significantly higher than that of bead-activated CART. Indeed, only the former showed cytotoxicity against Nalm6 leukemic cells expressing low levels of the CD19 target antigen CART. Furthermore, in an in vivo NSG model with Nalm6 leukemia, the adoptive transfer of low numbers of DBTA-generated CART (2e6) resulted in leukemia eradication and delayed leukemia relapse. Mechanistically, the enhanced function of DBTA-generated CAR was associated with increased metabolic activity in the pre-infusion product. These results suggest that calibrating the activation potential of CAR-T cells can result in the generation of a product with enhanced therapeutic potential.

Citation Format: Mehdi Benzaoui, Sooraj R. Achar, Vandana Keskar, Anup Sood, Brian M. Davis, Steven L. Highfill, Grégoire Altan-Bonnet, Christopher D. Chien, Naomi Taylor. Novel DNA-based-T-cell-activation for the generation of chimeric antigen receptor T cells with enhanced anti-leukemia cytotoxicity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB103.
Abstract LB119: Precision combination therapies based on recurrent oncogenic co-alterations
Authors: Korkut Anil , Li Xubin , Kong Elizabeth , Yan Gonghong , Dereli Zeynep , Bozorgui Behnaz , Imanirad Parisa , Elnaggar Jacob , Luna Augustin , Menter David , Pilié Patrick , Yap Timothy , Kopetz Scott , Sander Chris
Published: June 2022

Cancer cells depend on multiple driver alterations whose oncogenic effects can be suppressed by drug combinations. Discovering effective combination therapies and selecting patients to maximize therapeutic benefit are challenging due to the complexity of the molecular landscape of drug responses. Here, we provide a comprehensive resource of precision combination therapies tailored to oncogenic co-alterations that are recurrent across patient cohorts. To generate the resource, we developed REcurrent Features Leveraged for Combination Therapy (REFLECT), which integrates machine learning and cancer informatics algorithms. Based on multi-omic data, the method maps recurrent co-alteration signatures in patient cohorts to combination therapies. The resource matches > 2,000 drug combinations to co-alteration signatures across 201 cohorts stratified from 10,392 patients and 33 cancer types. We validated the REFLECT pipeline using data from patient-derived xenografts (PDX), in vitro drug screens, and combination therapy clinical trials. These validations demonstrate that REFLECT selects combination therapies with significantly improved efficacy, drug synergy, and survival outcomes. In patient cohorts with immunotherapy response markers, HER2 activation, and DNA repair aberrations, we have identified therapeutically actionable and recurrent co-alteration signatures. REFLECT provides a resource and framework to design combination therapies tailored to tumor cohorts in data-driven clinical trials and pre-clinical studies.

Citation Format: Anil Korkut, Xubin Li, Elizabeth Kong, Gonghong Yan, Zeynep Dereli, Behnaz Bozorgui, Parisa Imanirad, Jacob Elnaggar, Augustin Luna, David Menter, Patrick Pilié, Timothy Yap, Scott Kopetz, Chris Sander. Precision combination therapies based on recurrent oncogenic co-alterations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB119.
Abstract LB136: Characterization of a novel PI3Kinase inhibitor for treatment of glioblastoma multiforme
Authors: Fonkem Ekokobe , Newell-Rogers M. Karen , Tobin Richard , Healey Debbie , Das Mita , Bowen Sara , Quarles Chad , Clark John
Published: June 2022

The purpose of this study was to test the effects of a novel small molecule inhibitor of phosphatidylinositol-3 kinase (PI3K) for the treatment of glioblastoma multiforme (GBM). The key hurdles to effective treatment for GBM, the “most deadly” form of brain cancer, are resistance to chemotherapy, to radiation, and to immune check point inhibitor therapy. The overarching goal of our experiments has been to determine if a well-characterized small molecule inhibitor of PI3K, GCT.Glio.1, would improve treatment outcomes for GBM patients. The PI3K pathway has been shown to confer both chemotherapy and radiation resistance in GBM. GCT.Glio.1 (NPT520-337), a small molecule compound known to cross the blood brain barrier (BBB), was developed to target PI3K to treat GBM. GBMs, like other “difficult to treat” tumors, often over-express and actively utilize the PI3K pathway for survival, cell growth, and cell division. We used this small molecule inhibitor to determine how targeting the PI3K pathway impacts treatment resistance in GBM. We hypothesized that targeting PI3K would result in growth arrest, increase cell surface expression of a key immune check-point inhibitor target PD-L1, and would sensitize the GBM to treatment with radiation. Treatment of GL261 mouse GBM and U251 human GBM cell lines with GCT.Glio.1 resulted in profound growth arrest at the G2/M checkpoint, increased the cell surface expression of PD-L1, and synergized with radiation to cause growth arrest and subsequent cell death. In conclusion, these results indicate that GCT.Glio.1 may be a strong candidate for treatment of GBM, and suggest that GCT.Glio.1 is a candidate for rationally designed combinations with currently available radiation and immune checkpoint inhibitor therapies. Currently, the animal studies using GCT.Glio.1 in the GL261 mouse model of GBM have been initiated. Based on our promising pre-clinical data and early encouraging results from pre-clinical pharmacology and safety studies, we anticipate filing a pre-Investigational New Drug application (pre-IND) as the next step toward our goal of a clinical trial using GCT.Glio.1 for GBM patients.

Citation Format: Ekokobe Fonkem, M. Karen Newell-Rogers, Richard Tobin, Debbie Healey, Mita Das, Sara Bowen, Chad Quarles, John Clark. Characterization of a novel PI3Kinase inhibitor for treatment of glioblastoma multiforme [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB136.
Abstract LB157: Prevalence of metabolic syndrome among cancer survivors in the US
Authors: Ezeani Adaora , Agurs-Collins Tanya
Published: June 2022

Background: The purpose of this study was to determine the prevalence of metabolic syndrome (MetS) and its components in cancer survivors (CS) compared to participants without a history of cancer who have at least one chronic disease (CD) and those without a chronic disease diagnosis (NCD).

Methods: Using National Health and Nutrition Examination Survey (NHANES) data from 2015 to 2018, the prevalence MetS was evaluated among participants 50 years and older (n= 5466). MetS was defined based on the National Cholesterol Education Program’s Adult Treatment Panel III. Weighted data were used to estimate the prevalence of MetS, stratified by cancer site, gender, sex, and race/ethnicity. Chi-square test and logistic regression was used to assess group comparisons and associations respectively.

Results: Prevalence of MetS was higher among CS (71.4%) and CD (75.1%) participants compared to NCD (45.7%). Compared to NCD, participants with uterine cancer (UCa) and non-melanoma skin cancer (nMSC) had higher odds of MetS, with and without adjusting for covariates (p<0.05). Those with UCa had the highest odds of MetS (OR 3.49, CI 1.51 - 8.06, p<0.01) among all cancer types and NCD respondents. Regarding individual components of MetS, PCa survivors had lower odds of having elevated WC (p<0.01) and BrCa and UCa had higher odds of having elevated WC (p<0.05) after adjusting for covariates, compared to NCD. nMSC had higher odds of reduced HDL, elevated TG, and elevated WC (p<0.05) after adjusting for covariates.

Conclusions: This study indicates that UCa and nMSC survivors have a strong association with MetS. In particular, nMSC survivors demonstrated statistically significant odds of meeting 3 of the 5 risk factors for MetS after adjusting for confounding variables. A better understanding of the association between MetS, its components, and specific cancers can provide insight into providing complete clinical care to CS.

Citation Format: Adaora Ezeani, Tanya Agurs-Collins. Prevalence of metabolic syndrome among cancer survivors in the US [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB157.
Abstract LB162: Human herpesvirus 8 infection is associated with prostate cancer among IFNL4-ΔG carriers
Authors: Jenkins Frank J. , Minas Tsion Z. , Tang Wei , Dorsey Tiffany H. , Ambs Stefan
Published: June 2022

Background: Chronic inflammation as seen with chronic infections, has been proposed as a risk factor for prostate cancer. Numerous studies failed to identify a specific microbial agent associated with prostate cancer risk. We have previously reported that human herpesvirus 8 (HHV-8) is associated with increased prostate cancer risk in Tobago; a population that is 97% of African ancestry. This association was not found in several studies of US men, who were predominately of European American ancestry. It is unclear if the discrepancies between US and Tobago men are due to differences in HHV-8 seroprevalence rates or ancestry-related genetics. Previous studies have reported that the dinucleotide germline variant, rs368234815-ΔG, in the IFNL4 gene encoding interferon λ4 is more prevalent among individuals of African ancestry and impairs viral clearance. In this study, we investigated whether the association of HHV-8 with prostate cancer is IFNL4-ΔG-dependent.

Methods: We investigated the association of HHV-8 seropositivity with prostate cancer in 728 IFNL4-ΔG-genotyped cases and 813 genotyped population-based control men from the NCI-Maryland Prostate Cancer Case-Control study. Associations between HHV-8 and prostate cancer were assessed in multivariable unconditional logistic regression models. We calculated adjusted odds ratios (OR) and stratified the analysis into men harboring the IFNL4-ΔG-variant and non-carriers (ΔG/ΔG or ΔG/TT vs. TT/TT).

Results: HHV-8 seropositivity was higher in cases than controls (OR 1.76; 95%CI: 1.20 - 2.59). The association of HHV-8 seropositivity with prostate cancer was restricted to carriers of the ΔG allele (OR 2.19: 95%CI: 1.38 - 3.48). HHV-8 seropositivity did not associate with prostate cancer among TT/TT genotype carriers (OR 1.03: 95%CI: 0.51 - 2.11). Further stratification by race/ethnicity showed that HHV-8 is associated with prostate cancer exclusively among carriers of the ΔG allele in both European American (OR 2.59; 95%CI: 1.20 - 5.56) and African American men (OR 1.96; 95%CI: 1.08 - 3.56).

Conclusions: HHV-8 seropositivity is associated with increased odds of prostate cancer in men harboring the IFNL4 rs368234815-ΔG variant.

Impact: The study establishes IFNL4-ΔG as a candidate prostate cancer risk factor in men with an HHV-8 infection. This gene-environment association of IFNL4-ΔG with prostate cancer should be further evaluated using prospective study designs.

Citation Format: Frank J. Jenkins, Tsion Z. Minas, Wei Tang, Tiffany H. Dorsey, Stefan Ambs. Human herpesvirus 8 infection is associated with prostate cancer among IFNL4-ΔG carriers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB162.
Abstract LB175: MicroRNA-138 suppresses glioblastoma proliferation through downregulation of CD44 and sensitizes to temozolomide
Authors: Lee Tae Jin , Yoo Ji Young , Nam Deokhwa , Shim Ji Seon , Bueso-Perez Alberto , Kaur Balveen
Published: June 2022

Tumor suppressive microRNAs (miRNAs) are increasingly implicated in the development of anti-tumor therapy by reprogramming gene network that are aberrantly regulated in cancer cells. This study aimed to pinpoint tumor suppressive miRNAs with therapeutic potential against GBM, one of the most deadly cancers. Whole transcriptome and miRNA expression profiling analyses were performed on human GBM patient tissues. Transient transfection of miRNA mimics was used to investigate the tumor suppressive role of a miRNA (miR-138) in cell proliferation, cell cycle, migration, would healing, and chemosensitivity to temozolomide (TMZ). Orthotopic xenograft mice model using human patient-derived primary GBM cells was used for the survival studies. miR-138 was found as one of the most significantly downregulated miRNAs with an inverse correlation with CD44 expression. Functional studies unveiled that miR-138 negatively regulates the expression of CD44 at protein level by directly binding to the 3’ UTR of CD44. CD44 inhibition by miR-138 overexpression resulted in an inhibition of glioblastoma cell proliferation in vitro through cell cycle arrest as evidenced by a significant induction of p27 and its translocation into nucleus. Ectopic expression of miR-138 also increased survival rates in mice that had an intracranial xenograft tumor derived from human patient-derived primary GBM cells. In addition, miR-138 sensitized GBM tumor to TMZ in mice. We demonstrated a therapeutic potential of tumor suppressive miR-138 through direct downregulation of CD44 and sensitization to chemotherapy for the treatment of primary and even chemoresistant GBM

Citation Format: Tae Jin Lee, Ji Young Yoo, Deokhwa Nam, Ji Seon Shim, Alberto Bueso-Perez, Balveen Kaur. MicroRNA-138 suppresses glioblastoma proliferation through downregulation of CD44 and sensitizes to temozolomide [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB175.
Abstract LB197: Tucatinib has selective activity in HER2-positive cancers and significant combined activity with approved and novel breast cancer targeted therapies
Authors: O'Brien Neil A. , Huang Holly K. , McDermott Martina S. , Madrid Athena , Luo Tong , Ayala Raul , Issakhanian Shawnt , Gong Ke Wei , Lu Ming , Zhang Jun , Slamon Dennis J.
Published: June 2022

Pharmacologically targeting the HER2 oncoprotein with therapeutics such as the monoclonal antibody (mAb), trastuzumab, provides clinical benefit for patients with HER2-positive (HER2+) cancers. However, a significant number of patients eventually progress on these therapies. Efforts to overcome therapeutic resistance through combination therapy with small molecule inhibitors of HER2 have been limited by toxicities associated with off-target activity and/or limited efficacy. In this preclinical study, we explore single-agent and combined activity of tucatinib, a novel HER2-selective small molecule inhibitor. Tucatinib demonstrated potent, selective activity in a panel of 456 human cancer cell lines, with activity restricted to cell lines (breast and non-breast) with HER2-amplification, including models of acquired resistance to trastuzumab. Within the HER2+ population, tucatinib response tracked strongly with HER2-driven signaling. Single agent tucatinib induced tumor regressions in xenograft models of HER2+ breast cancer and combination with trastuzumab induced a complete and sustained blockade of HER2/PI3K/AKT-signaling. Efficacy of the tucatinib/trastuzumab combination matched that induced by current standard of care (SOC) trastuzumab/pertuzumab/docetaxel combination, with the exception that the chemotherapy-sparing tucatinib/trastuzumab combination did not require a dosing holiday to achieve the same efficacy. In xenograft models of HER2+ breast cancer that also express estrogen receptor (ER) (HER2+/ER+), tucatinib showed combined efficacy with inhibitors of CDK4/6 and ER, indicating potential novel therapeutic strategies for difficult-to-treat subtypes of HER2+ breast cancer. These data support expanded clinical investigations of tucatinib as a combination partner for other novel and approved targeted therapies for HER2-driven malignancies.

Citation Format: Neil A. O'Brien, Holly K. Huang, Martina S. McDermott, Athena Madrid, Tong Luo, Raul Ayala, Shawnt Issakhanian, Ke Wei Gong, Ming Lu, Jun Zhang, Dennis J. Slamon. Tucatinib has selective activity in HER2-positive cancers and significant combined activity with approved and novel breast cancer targeted therapies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB197.
Abstract LB210: Preclinical development and evaluation of allogeneic CAR T cells targeting CD70 for the treatment of renal cell carcinoma
Authors: Panowski Siler , Srinivasan Surabhi , Tan Nguyen , Tacheva-Grigorova Silvia , Smith Bryan , Mak Yvonne , Ning Hongxiu , Villanueva Jonathan , Wijewarnasuriya Dinali , Lang Shanshan , Melton Zea , Ghosh Adit , Dusseaux Mathilde , Galetto Roman , Heyen Jonathan , Sai Tao , Van Blarcom Thomas , Chaparro-Riggers Javier , Sasu Barbra
Published: June 2022

CD70 is highly expressed on renal cell carcinoma (RCC), with limited normal tissue expression, making it an attractive CAR T target for an immunogenic solid tumor indication. Here we generated and characterized a panel of anti-CD70 scFv-based CAR T cells. Despite the expression of CD70 on T cells, production of CAR T from a subset of scFvs with potent in vitro activity was achieved. Expression of CD70 CARs was found to mask CD70 detection in cis and provide protection from CD70 CAR T-mediated fratricide. Two unique classes of CAR T cells were identified with differing memory phenotype, activation status, and cytotoxic activity. Epitope mapping revealed CARs binding to the membrane distal region of the CD70 extracellular domain (ECD) fall into the more active and differentiated class, as compared to CARs binding the membrane proximal region of the CD70 ECD. CD70 CAR T cells were evaluated with rituximab-based off switches to provide control over CAR T function and displayed robust antitumor activity against RCC cell lines and patient-derived xenografts in mouse models. Tissue cross reactivity studies to evaluate off-target binding with two lead CARs showed membrane staining in rare tissue-resident lymphocytes, thus matching the known expression pattern of CD70. Expected findings related to T cell activation, and elimination of CD70-expressing cells were observed in a cynomolgus monkey CD3-CD70 bispecific toxicity study and included cytokine release and loss of cellularity in lymphoid tissues. Lastly, highly functional CD70 allogeneic CAR T cells were produced at large scale through elimination of the T cell receptor by TALEN® gene editing. Taken together, these efficacy and safety data support the evaluation of CD70 CAR T cells for the treatment of RCC and led to the advancement of an allogeneic CD70 CAR T candidate into Phase I clinical trials.

Citation Format: Siler Panowski, Surabhi Srinivasan, Nguyen Tan, Silvia Tacheva-Grigorova, Bryan Smith, Yvonne Mak, Hongxiu Ning, Jonathan Villanueva, Dinali Wijewarnasuriya, Shanshan Lang, Zea Melton, Adit Ghosh, Mathilde Dusseaux, Roman Galetto, Jonathan Heyen, Tao Sai, Thomas Van Blarcom, Javier Chaparro-Riggers, Barbra Sasu. Preclinical development and evaluation of allogeneic CAR T cells targeting CD70 for the treatment of renal cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB210.
Abstract LB216: Pre-clinical characterization of NGM831, an ILT3 antagonist antibody for the treatment of solid tumors
Authors: Chen Peirong , Crawley Suzanne C. , Lin Vicky Y. , Kapoor Varun , Paavola Kevin J. , Chen Hung-I , Lichtman Joshua S. , Li Betty , Mondal Kalyani , Kutach Alan K. , Wang Yan , Kaplan Daniel D. , Roda Julie M.
Published: June 2022

Suppressive myeloid cells inhibit antitumor immunity by preventing T cell responses. Immunoglobulin-like transcript 3 (ILT3, also known as LILRB4) is highly expressed on tumor-associated myeloid cells and promotes their suppressive phenotype. Our team recently identified fibronectin as a functional ligand for ILT3. The fibronectin-ILT3 interaction serves as a “stromal checkpoint” through which the extracellular matrix actively promotes myeloid cell suppression in the tumor microenvironment. We now report the pre-clinical characterization of NGM831, a humanized IgG1 (N297G) antibody that binds to ILT3 of human and cynomolgus monkey origin with high specificity and sub-nM affinity and blocks the interaction of ILT3 with both its reported ligands, fibronectin and ApoE. In a gene expression profiling experiment, treatment of tolerogenic dendritic cells with NGM831 in the presence of fibronectin decreased their expression of inhibitory and scavenger receptors (CD163, MRC1, MARCO, STAB1, LILRB2) and markers of dendritic cell immaturity (CD14, CD209, FOLR2) and increased their expression of genes involved in antigen presentation (TNFSF14, DCSTAMP, CD82, OLR1) and TH1 polarization (SPP1, TBX21), suggesting that these cells had been remodeled to a more stimulatory phenotype. Consistent with these observations, treatment of tolerogenic dendritic cells with NGM831 increased their production of pro-inflammatory cytokines in response to FcɣR ligation, restored their responsiveness to maturation stimuli such as lipopolysaccharide (LPS) and CD40 ligand (CD40L), and increased their production of chemokines that could induce the migration of other immune cells to sites of inflammation. In addition, NGM831 acted synergistically with pembrolizumab to increase the ability of dendritic cells to stimulate allogeneic T cells in mixed lymphocyte reactions. Taken together, these results demonstrate that NGM831 can block fibronectin-mediated immunosuppression and promote myeloid cell reprogramming. These data support the clinical development of the ILT3 antagonist antibody NGM831 alone and in combination with immune checkpoint blockade. NGM831 is expected to enter clinical trials for the treatment of advanced solid tumors in early 2022.

Citation Format: Peirong Chen, Suzanne C. Crawley, Vicky Y. Lin, Varun Kapoor, Kevin J. Paavola, Hung-I Chen, Joshua S. Lichtman, Betty Li, Kalyani Mondal, Alan K. Kutach, Yan Wang, Daniel D. Kaplan, Julie M. Roda. Pre-clinical characterization of NGM831, an ILT3 antagonist antibody for the treatment of solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB216.
Abstract LB218: A safe and highly potent anti-PD-1-IL-2c fusion that decouples efficacy and toxicity of IL-2 therapy
Authors: Ye Fan , Huang Jianing , Huang Zoey , Chen Sandra , Liao Eric , Li Ella , Quach Allison , Jiang Jenny , Lin Hanna , Hua Michael , Yung Savannah , Cheng Lili , Zhong Ziyang
Published: June 2022

Interleukin 2 (IL-2) is a pivotal immune agonist for tumor immunotherapy that has produced impressive clinical efficacy in a number of cancer types. Nevertheless, its pleiotropic effect has led to prohibitory side effects and immune restraint. In contrast, the PD-1 blockade-based cancer immunotherapy has a good safety profile by targeting and sustaining the activity of tumor-antigen specific T cells within cancer tissues. To take full advantage of complementary antitumor activity of PD-1 monoclonal antibody (mAb) and IL-2 as well as supreme intratumoral T-cell-targeting property of PD-1, a bifunctional fusion protein composed of PD-1 mAb and IL-2 mutein (αPD-1-IL-2c) is designed. IL-2c is a chimeric molecule that contains a fragment from IL-15 and does not bind to IL-2 receptor alpha (IL-2Rα). αPD-1-IL-2c stimulated greater pSTAT5 activation and proliferation in PD-1+ T cells than PD-1- T cells. αPD-1-IL-2c also induced a much stronger anti-tumor immune response compared to PD-1 mAb, IL-2c, or PD-1 mAb in combination with IL-2c in multiple syngeneic models such as B16F10, CT26, and MC38. In CT26 and MC38 models, αPD-1-IL-2c achieved complete response starting from 0.3 mg/kg dosing. In B16F10 model, αPD-1-IL-2c showed greater than 70% tumor growth inhibition (TGI). Global gene expression profiling studies showed that PD-1-IL-2c treatment significantly elevated expression levels of Cd3d, Cd3e, Cd8a, Il2rα, Cxcr3, Cxcr6, Zap70, Lck, and Pdcd1 in tumor tissues compared to treatment with PD-1 mAbs or IL-2c, indicating a specific expansion and activation of T cell in the tumor microenvironment (TME). The safety profile of αPD-1-IL-2c was assessed and compared to WT IL-2 and a leading “No-α” αPD-1-IL-2 fusion protein (αPD-1-IL-2x). WT IL-2 and αPD-1-IL-2x induced significant body weight loss and severe splenomegaly when dosed at 1.25 mg/kg. In contrast, αPD-1-IL-2c dosed at 10 mg/kg did not cause appreciable body weight loss and only led to minimal splenomegaly. In summary, we have developed a safe and highly potent αPD-1-IL-2 mutein that achieves full PD-1 blockade and TME-specific T cell activation and expansion without appreciable toxicity.

Citation Format: Fan Ye, Jianing Huang, Zoey Huang, Sandra Chen, Eric Liao, Ella Li, Allison Quach, Jenny Jiang, Hanna Lin, Michael Hua, Savannah Yung, Lili Cheng, Ziyang Zhong. A safe and highly potent anti-PD-1-IL-2c fusion that decouples efficacy and toxicity of IL-2 therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB218.
Abstract LB503: Using JBrowse 2 plugins to visualize cancer genomic data
Authors: Haw Robin Andrew , Diesh Colin , Bridge Caroline , Buels Rob , Stevens Garrett , Xie Peter , Martinez Teresa , Hershberg Elliot , Zhang Junjun , Dider Shihab , Cain Scott , Stein Lincoln , Holmes Ian
Published: June 2022

Genome browsers are essential tools for integrating, exploring, and visualizing data from large cancer genomics datasets. JBrowse 2 is a JavaScript genome browser with novel features for visualizing structural variants, syntenic alignments, and multiple types of genomic data. Although JBrowse 2 is available as a web-based or desktop application, the capabilities and features are not fixed and can be expanded through a comprehensive plugin system. To help address users' needs, we launched the new JBrowse 2 Plugin Store (https://jbrowse.org/jb2/plugin_store/). The overarching goals of the Plugin Store are to showcase the crucial features plugins add to JBrowse 2, to enable researchers to search for plugins they need, and for developers to highlight their plugins. The plugin system spans all aspects of the JBrowse 2 application and enables new track types (e.g. Manhattan plots, Hi-C data, ideograms), data adapters (e.g. API endpoint adapters for NCI Genomic Data Commons and the International Cancer Genome Consortium), and views (e.g. dot plots and multiple sequence alignments). Here, we present the capabilities of JBrowse 2 plugins and describe usage scenarios for cancer biologists and bioinformaticians, and software developers.

Citation Format: Robin Andrew Haw, Colin Diesh, Caroline Bridge, Rob Buels, Garrett Stevens, Peter Xie, Teresa Martinez, Elliot Hershberg, Junjun Zhang, Shihab Dider, Scott Cain, Lincoln Stein, Ian Holmes. Using JBrowse 2 plugins to visualize cancer genomic data [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB503.