bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5964: Context-dependent induction of interferon signaling by CD11b agonists supports anti-tumor immunity in mouse models and human cancer patients
Authors: Liu Xiuting , Hogg Graham , Zuo Chong , Baer John , Lander Varintra , Kang Liang , Borcherding Nicholas , Knolhoff Brett , Osterhout Robin , Galkin Anna , Bruey Jean , Carter Laura , Mpoy Cedric , Schwarz Julie , Park Haeseong , Gupta Vineet , DeNardo David
Published: April 2023

Chronic activation of inflammatory pathways and suppressed interferon signaling are hallmarks of myeloid cells in immunosuppressive tumors that drive poor responsiveness to conventional and immune therapies. Previous studies have identified agonistic activation of the CD11b integrin as a potential strategy to enhance anti-tumor immunity. However, the mechanisms by which CD11b-agonism reprogram tumor immunity are poorly understood, and this may impair patient selection and identification of effective treatment combinations. Here we will use a combination of in vitro systems, animal models, and samples from first in human clinical trials of the CD11b-agonist to identify the mechanism of action of this approach and identify combinations for further testing. CD11b agonism alters tumor-associated macrophage (TAM) phenotypes by simultaneously repressing NFκB/IL1-signaling and activating interferon (IFN) gene expression. Repression of NFκB/IL-1 signaling was due to rapid degradation of p65 protein by the proteosome, contributing to suppressing myeloid cells infiltration. In contrast, CD11b agonism triggers mitochondrial dysfunction to stimulate STING-induced, STAT1-mediated interferon signaling, contributing to macrophages-augmented anti-tumor T cell immunity. Tissues from phase I clinical trials shows that CD11b agonist activates STING and STAT1 signaling in TAMs in human tumors, which is in consistent with preclinical data. Furthermore, combining CD11b agonism with cytotoxic therapies, STING agonist or TLRs agonists leads to robust anti-tumor activity in PDAC models. These studies pave the way for mechanism-based therapeutic combination strategies in cancer patients.

Citation Format: Xiuting Liu, Graham Hogg, Chong Zuo, John Baer, Varintra Lander, Liang Kang, Nicholas Borcherding, Brett Knolhoff, Robin Osterhout, Anna Galkin, Jean Bruey, Laura Carter, Cedric Mpoy, Julie Schwarz, Haeseong Park, Vineet Gupta, David DeNardo. Context-dependent induction of interferon signaling by CD11b agonists supports anti-tumor immunity in mouse models and human cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5964.
Abstract 5968: Leukemia inhibitory factor regulates macrophage immune response in head and neck squamous cell carcinoma
Authors: Sui Yun Hua , Liu Tzu Tung , Liu Shu Chen
Published: April 2023

The high recurrence rate of head and neck squamous cell carcinoma (HNSCC) is associated with an immune suppressive tumor microenvironment (TME). Tumor-associated macrophage (TAM)-mediated immunosuppression is a critical feature in HNSCC TME. We provide evidence demonstrating that leukemia inhibitory factor (LIF) is involved in macrophage polarization and remodeling of the HNSCC microenvironment. By interrogating the head and neck squamous cell carcinoma RNA sequencing dataset extracted from the TCGA database, we found that the levels of LIF and M2 macrophage markers (CD163, CD206, VEGF) were enhanced in tumors compared to normal counterparts. Higher LIF expression in tumors was further correlated with worse overall survival. Immunohistochemical analysis found that macrophages with higher LIF immunoreactivities were located at the periphery of HNSCC tumors. In a macrophage-cancer cell coculture system, the presence of LIF promoted the proliferation and mobility of cancer cells and induced an M2-dominant macrophage polarization. Stimulating monocyte-derived macrophages (MDMs) with LIF increased the expression of several M2 markers (CD163, CD206, CD209, and IL10) but decreased the expression of M1 markers (iNOS, CD80, and CD86). Moreover, LIF-treated macrophages exhibited little cancer cytotoxicity compared to vehicle-treated macrophages. Treating macrophages with soluble LIF receptor (sLIFR), a LIF antagonist, partly reversed the LIF-mediated M2 polarization and enhanced cytotoxicity toward cancer cells. Results of RNA-sequencing data demonstrated that LIF suppressed antigen presentation process, type I interferon production, TNFR signaling, and molecules participating in the Hippo signaling pathway in MDMs. Mechanistic studies found that LIF might trigger M2 polarization via activating YAP1, as reflected by a reduction of p-YAP1 (S127) and an enhanced YAP1 nuclear localization in macrophages. Treating macrophages with YAP1 inhibitors (Saracatinib and Verteporfin) blocked the LIF-mediated YAP1 nuclear translocation, expression of M2 markers, and tumor-promoting effects. Our findings suggest that the presence of LIF in HNSCC promotes macrophage M2 polarization through YAP1 signaling, which assists in establishing an immune-suppressive, tumor-promoting microenvironment. The blockade of LIF-mediated effects may tailor therapeutic strategies by converting the immunosuppressive microenvironment for selected HNSCC patients.

Citation Format: Yun Hua Sui, Tzu Tung Liu, Shu Chen Liu. Leukemia inhibitory factor regulates macrophage immune response in head and neck squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5968.
Abstract 6086: PALB2 germline mutations in a large cohort Middle Eastern breast-ovarian cancer patients
Authors: Bu Rong , Sira Abdul K. , Parvathareddy Sandeep , Iqbal Kaleem , Azam Saud , Qadri Zeeshan , Al-Rasheed Maha , Haqawi Wael , Diaz Mark , Victoria Ingrid G. , Al-Kuraya Khawla S.
Published: April 2023

Background: The PALB2 gene encoding protein is involved in the homologous recombination repair pathway and plays an important role in maintaining genomic integrity. PALB2 heterozygous pathological variants (PV) or likely pathogenic variants (LPV) are associated with increased risk of breast and ovarian cancer. However, the prevalence and clinicopathological association of PALB2 germline PV/LPV in Middle Eastern breast and ovarian cancers is not fully identified.

Purpose: We retrospectively screened a cohort of 918 cancer patients (791 breast cancer and 127 ovarian cancer) from Saudi Arabia using targeted capture-based next generation sequencing (NGS) method for PALB2 germline variants regardless the family history of these patients or the presence of other hereditary cancer susceptibility genes mutations. Clinicopathological criteria were also fully analyzed.

Results: Five heterozygous PVs or LPVs were identified in six cases, accounting for 0.65% (6/918) of entire cohort. Two cases (33.3%) harbored PVs and four cases (66.7%) carried LPVs. Four PVs/LPVs (80%) were frameshift along with one novel splicing LPV (c.2835-1 C>A). One recurrent LPV (c.3425delT) was identified in two cases. All six affected carriers have breast cancer diagnosis with median age of 39.5 years (range 34-49 years). Only two cases (33%) have documented family history of cancer. Breast cancer phenotype was invasive ductal unilateral cancer in all cases with 66.7% of hormone receptor positive and 16% of triple negative tumors.

Conclusion: Germline PVs/LPVs in the PALB2 gene were observed in low frequency of 0.65% in Saudi breast and/or ovarian cancer. Our study confirms one recurrent LPV and one novel LPV in Saudi breast cancer patients.

Citation Format: Rong Bu, Abdul K. Sira, Sandeep Parvathareddy, Kaleem Iqbal, Saud Azam, Zeeshan Qadri, Maha Al-Rasheed, Wael Haqawi, Mark Diaz, Ingrid G. Victoria, Khawla S. Al-Kuraya. PALB2 germline mutations in a large cohort Middle Eastern breast-ovarian cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6086.
Abstract 6128: Deubiquitinating enzyme Inhibitor PR-619 inducesendoplasmic reticulum stress-related apoptosisin human chondrosarcoma
Authors: Kuo Kuan-Lin , Hsu Chen-Hsun , Liao Shih-Ming , Huang Kuo-Yuan
Published: April 2023

It is reported that PR-619 is a deubiquitination enzyme inhibitor that can exert anti-tumor effects on a variety of malignancies. We conducted this study to explore the antitumor effects of PR-619 on chondrosarcoma in vitro and in vivo by using two different classes of human chondrosarcoma cell lines SW-11353 and JJ012. To determine these effects, we measured cell viability (MTT), apoptosis (detection of Annexin V-FITC labeling using flow cytometry) and western blot to evaluate molecules associated with apoptosis and cell stress. In addition, we used a nude mouse xenograft mouse model to determine the effect of PR-619 on tumor growth. As our data revealed, in addition to inducing BAD and activating Capase-7, Caspase-8, and PARP, PR-619 also has a dose-effect that induces cytotoxicity, proliferation restriction, and apoptosis in these human chondrosarcoma cells. PR-619 has also been found to activate endoplasmic reticulum pressure-related molecules (caspase-4 and CHOP) and other stress responses (activation of JNK and c-Jun). We conclusively demonstrated the ability of PR-619 to inhibit tumor growth while achieving minimal general toxicity in a developed xenograft mouse model of chondrosarcoma. Therefore, we conclude that PR-619 exacts an antitumor effect in conjunction with cellular and endoplasmic reticulum pressure in human chondrosarcoma. These findings suggest that PR-619 may provide a novel therapeutic strategy for chondrosarcoma.

Citation Format: Kuan-Lin Kuo, Chen-Hsun Hsu, Shih-Ming Liao, Kuo-Yuan Huang. Deubiquitinating enzyme Inhibitor PR-619 inducesendoplasmic reticulum stress-related apoptosisin human chondrosarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6128.
Abstract 6225: SERPINB3 promotes the aggressive basal-like/squamous subtype and correlates with poor prognosis in pancreatic ductal adenocarcinoma through metabolic reprogramming
Authors: Ohara Yuuki , Tang Wei , Huaitian Liu , Yang Shouhui , He Peijun , Cawley Helen , Valenzuela Paloma , Zhang Lin , Gaedcke Jochen , Ghadimi B. Michael , Gaida Matthias M. , Bergmann Frank , Alexander H. Richard , Hanna Nader , Ambs Stefan , Hussain S. Perwez
Published: April 2023

In this study, we aimed to find genes with a key function in the development of molecular subtypes in pancreatic ductal adenocarcinoma (PDAC). Through transcriptome analysis, we discovered that the endogenous serine/cysteine proteinase inhibitor SERPINB3 (squamous cell carcinoma antigen 1, SCCA1) was distinctively upregulated in the basal-like/squamous subtype, known as an aggressive subtype, and this upregulation associated with decreased patient survival in both a test (N=123) and a validation cohort (N=84). In additional investigations of the tumor metabolome and transcriptome using PDAC patient tumors and cell lines, SERPINB3 and the basal-like/squamous subtype showed a robust relationship with upregulated levels of amino acids (e.g., hydroxyproline) whereas SERPINB3 promoted a gene signature indicative of the basal-like/squamous subtype. Additional mechanistic studies revealed that SERPINB3 and hydroxyproline promoted the migration/invasion of PDAC cells. Moreover, SERPINB3 also promoted metastasis in an orthotopic mouse model of PDAC through stromal factors that increased tumor microvessel density. To conclude, inhibiting SERPINB3 function may attenuate disease progression of the basal-like/squamous subtype in PDAC through changes to the tumor stroma and tumor metabolism.

Citation Format: Yuuki Ohara, Wei Tang, Liu Huaitian, Shouhui Yang, Peijun He, Helen Cawley, Paloma Valenzuela, Lin Zhang, Jochen Gaedcke, B. Michael Ghadimi, Matthias M. Gaida, Frank Bergmann, H. Richard Alexander, Nader Hanna, Stefan Ambs, S. Perwez Hussain. SERPINB3 promotes the aggressive basal-like/squamous subtype and correlates with poor prognosis in pancreatic ductal adenocarcinoma through metabolic reprogramming [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6225.
Abstract 6236: Stellettin B induces apoptosis and autophagy in human bladder cancer RT112 cells
Authors: Chen Mei-Chuan , Chang Chun-Han
Published: April 2023

Bladder cancer is one of the most prevalent cancers worldwide. Although most of the patients have good prognosis and good life expectancy with standard treatments, recurrence rate and five-year survival rate have not been significantly improved in patients with bladder cancer, demonstrating there is an urgent need for development of a novel therapeutic strategy for the treatment of bladder cancer. Stellettin B (SP-2), a triterpene isolated from marine sponge Jaspis stellifera , suppresses cell viability in bladder cancer RT112 cells without severe toxicity toward normal uroepithelial SV-HUC-1 cells. Our results showed that SP-2 induces accumulation of cells at subG1 phase in parallel with increase of early apoptotic cells via annexin V/PI staining and activation of cell apoptotic death proteins. Moreover, non-cytotoxic concentrations of SP-2 induces LC3-II formation and p62 downregulation to activate autophagy in RT112 cells, suggesting autophagy may play a role in SP-2 -induced cell death. Inhibition of autophagy by pharmacological inhibitors (3-MA and chloroquine) or ATG5 knockout protects stellettin B-induced apoptosis and cell viability suppression, indicating SP-2 induces autophagy to promotes cell death. Taken together, stellettin B may be a promising therapeutic agent for bladder cancer treatment.

Citation Format: Mei-Chuan Chen, Chun-Han Chang. Stellettin B induces apoptosis and autophagy in human bladder cancer RT112 cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6236.
Abstract 6720: Using proteasome inhibition to hyperactivate the integrated stress response in aggressive pediatric brain tumors
Authors: Novak Orlandi Valencia , Findlay Tyler , Rubens Jeffrey , Eberhart Charles , Raabe Eric H.
Published: April 2023

H3K27-altered diffuse midline glioma (DMG) and atypical teratoid/rhabdoid tumor (AT/RT) are aggressive pediatric brain tumors with dismal outcomes. DMG and AT/RT have increased baseline activation of the integrated stress response (ISR), an evolutionarily conserved system that enables cells to tolerate various forms of stress. This activation is manifested by elevated levels of ATF4 and NRF2 in DMG and AT/RT, respectively. Transient or low-level expression of these transcription factors protect cells from stress, while sustained, high-level activation leads to cell death. Ixazomib is an orally bioavailable proteasome inhibitor that causes endoplasmic reticulum stress, which is a major upstream activator of the ISR. We hypothesized that the high baseline level of ATF4 in DMG and NRF2 in AT/RT would make these tumors susceptible to ISR activators such as ixazomib. After determining the IC50 of ixazomib, DMG and AT/RT cell lines (JHH-DIPG1, JHH-DIPG16A, and CHLA06) were treated with increasing concentrations of the drug. Cleaved caspase 3 immunofluorescence showed a significant increase of apoptosis in all cell lines (JHH-DIPG16A and CHLA06 p<0.0001, JHH-DIPG1 p=0.0008 by ANOVA). Additionally, western blots for cleaved PARP and phospho-Rb expression detected induction of apoptosis and suppression of cell proliferation in JHH-DIPG1 treated with ixazomib. We are currently testing ixazomib in combination with idarubicin, a brain-penetrant anthracycline, and gemcitabine, a brain-penetrant nucleoside analog. Synergy testing in CHLA06 showed an overall zero-interaction-potency (ZIP) synergy score of 23.464 with inhibitory concentrations of ixazomib and idarubicin in the low nanomolar range (scores of 10 or above indicate synergy). Similarly, ixazomib and gemcitabine synergized to suppress CHLA06 growth and induce apoptosis (67% Annexin V+ cells in combination compared to 14 and 24% Annexin V+ with single agent treatment). In the future, we will determine if ixazomib selectively kills DMG and AT/RT while sparing normal cells in iPSC brain organoids. We will also test ixazomib singly and in combination with traditional chemotherapy in orthotopic xenografts of AT/RT. These results suggest that ixazomib, especially in combination with idarubicin, gemcitabine or other ISR activators, has the potential to serve as an effective therapy for aggressive pediatric brain tumors.

Citation Format: Orlandi Valencia Novak, Tyler Findlay, Jeffrey Rubens, Charles Eberhart, Eric H. Raabe. Using proteasome inhibition to hyperactivate the integrated stress response in aggressive pediatric brain tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6720.
Abstract 6725: Targeting urea cycle dysfunction to prevent and treat osteosarcoma
Authors: Offenbacher Rachel , Ciero Paul , Loeb David
Published: April 2023

Introduction: Osteosarcoma (OS) is the most common primary malignant bone tumor in adolescents and young adults. Intensive multimodal treatment cures almost 75% of patients who present with localized disease; however, only 25% of patients who present with metastases become long term survivors, and those who suffer a metastatic relapse are almost never cured. Polyamine metabolism and signaling play important roles in multiple cancers but have not previously been studied in osteosarcoma. D, L-alpha-difluoromethylornithine (DFMO) is an irreversible inhibitor of ornithine decarboxylase (ODC), the initial, rate-limiting enzyme within the polyamine biosynthetic pathway, and has been studied in a number of different cancers as either a therapeutic or a chemopreventive agent. We investigated the role of polyamines in OS proliferation and metastasis and whether blocking the polyamine synthetic pathway with DFMO had therapeutic potential in the treatment of OS.

Methods: We evaluated proliferation, apoptosis, clonogenic growth and the ability to grow under nonadherent conditions in vitro using established OS lines. To investigate the effect of DFMO on tumor growth in vivo, we implanted fragments of patient derived xenograft into the tibias of NOD/SCID/IL-2Rγ null mice. Upon confirmation of tumor growth, mice were randomized to either receive drinking water or drinking water supplemented with 2% DFMO. A third cohort of mice received water supplemented with 2% DFMO only after hindlimb amputation.

Results: DFMO has a profound effect on the proliferation of OS cell lines in vitro. Utilizing caspase assays, we determined that DFMO does not induce apoptosis, but is cytostatic and inhibits proliferation. We found that DFMO prevents the clonogenic growth of 3 different OS cell lines in soft agar and prevents spheroid formation under non-adherent conditions. Interestingly, once established, spheroidss were not disrupted by the addition of DFMO. In vivo, administration of 2% DFMO after hindlimb amputation decreased local recurrence and limited metastasis (p=0.02).

Conclusion: DFMO inhibits proliferation and clonogenic growth in vitro, and decreases distant metastasis in vivo. Since pediatric dosing and safety data are already established, our findings are readily translatable to clinical trials.

Citation Format: Rachel Offenbacher, Paul Ciero, David Loeb. Targeting urea cycle dysfunction to prevent and treat osteosarcoma. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6725.
Abstract 6757: Identification of predictive factors for early relapse in patients with unresectable stage III NSCLC receiving consolidation durvalumab after concurrent chemoradiation
Authors: Yeo Chang Dong , Kang Hye Seon , Kim In Kyoung , Lee Sang Haak , Kim Jin Woo
Published: April 2023

Background: Patients with locally advanced, unresectable, non-small cell lung cancer (NSCLC) receiving definitive concurrent chemoradiation (CCRT) benefit from durvalumab consolidation therapy. However, predictive factors for early relapse during durvalumab maintenance were not identified.

Patients and Methods: The present study used the lung cancer cohort of the Catholic Medical Centers at the Catholic University of Korea from 2018 to 2021. In all, 51 NSCLC patients that were treated with durvalumab consolidation therapy after definitive CCRT. Early relapse was considered if it occurred within 6 months of starting initial durvalumab therapy.

Results: During study period, 15 (29.4%) relapsed among 51 included patients. Median time from initial therapy of durvalumab to progression was 107.73 ± 47.69 days in early relapse group. In mutivariate analysis, younger age (HR 0.713, 95% CI 0.572-0.888, P=0.003), higher pack years (HR 1.311, 95% CI 1.109-1.549, P=0.001), non-COPD (HR 0.030, 95% CI 0.001-0.677, P=0.027), anemia (HR 23.30, 95% CI 2.030-267.48, P=0.011) and stage IIIC (vs. stage IIIA) (HR 17.890, 95% CI 1.997-160.243, P=0.010) were independent predictive factors for early relapse during durvalumab consolidation therapy.

Conclusion: Younger age, higher pack years, non-COPD, anemia and stage IIIC were independent predictive factors for early relapse during durvalumab consolidation therapy in patients with unresectable stage III NSCLC after definitive CCRT. Careful patient selection and clinical attention are needed for high-risk individuals.

Citation Format: Chang Dong Yeo, Hye Seon Kang, In Kyoung Kim, Sang Haak Lee, Jin Woo Kim. Identification of predictive factors for early relapse in patients with unresectable stage III NSCLC receiving consolidation durvalumab after concurrent chemoradiation. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6757.
Abstract 6769: Precise spatial multiplexing of protein biomarkers for immune profiling in tissue samples with chip cytometry
Authors: Kwarta Karen , Campbell Thomas , Northcutt Adam , Schwarz Spencer
Published: April 2023

Immunohistochemistry is the most widely used diagnostic technique in tissue pathology. However, IHC is associated with several limitations including the labeling of just a few markers per tissue section and limited quantification of cell populations. As a result of plex limitations, key insights about tumor biology are missed, which could be important for advancing our understanding of tumor biology and ultimately improving patient outcomes. Chip Cytometry is a novel image-based platform for precise spatial multiplexing that addresses these challenges by combining iterative immuno-fluorescent staining with high-dynamic range imaging to facilitate quantitative phenotyping with single-cell resolution. The platform enables simultaneous detection of dozens of markers on a single tissue section and enables accurate quantification of protein expression levels necessary to deeply profile single cells, understand interactions between key immune cells, and identify topographic biomarkers. Here we demonstrate how standard FCS files are generated from multichannel OME TIFF images, enabling identification of cellular phenotypes via flow cytometry-like hierarchical gating. Quantification of results reveal precise expression levels for each marker in the assay in each individual cell in the sample, while maintaining spatial information about each cell. Chip Cytometry has the potential to advance precision medicine in immuno-oncology and inform the discovery of novel biomarkers by enabling quantitative analysis of cellular phenotypes in the spatial context. The Chip Cytometry platform enables simultaneous detection of multiple protein markers on a single tissue section for deep immune cell profiling in the tumor microenvironment. Combined with the single-cell spatial information, such data sets provide an opportunity for the discovery of new complex multiplexed biomarker signatures to inform therapeutic development.

Citation Format: Karen Kwarta, Thomas Campbell, Adam Northcutt, Spencer Schwarz. Precise spatial multiplexing of protein biomarkers for immune profiling in tissue samples with chip cytometry [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6769.
Abstract 6771: Interrogating the tumor-immune landscape with a novel automated RNAscope™ assay for multiplexed detection of RNA and protein
Authors: Dikshit Anushka , Basak Sayantani , Murlidhar Vasudha , Kim Ge-Ah , Yu Julia , Deshpande Sonali , Wang Li-Chong , Srinivasan Maithreyan
Published: April 2023

Understanding tissue heterogeneity is critical for elucidating cell-cell interactions with important implications in immuno-oncology, inflammation, and neuroscience. Tissue heterogeneity poses immense challenges to understanding underlying molecular mechanisms using techniques such as qRT-PCR or bulk sequencing. While single-cell RNA sequencing can provide information about precise cellular composition of tissues, data analysis can be cumbersome and spatial context is lost. With single-cell spatial platforms such as RNAscope, target gene and protein expression can be visualized to characterize cell types and tissue neighborhoods. Here, we demonstrate a novel method for the simultaneous detection of RNA and protein using a modified co-detection assay. This novel co-detection assay enables visualization of a combination of up to 12 RNA and/or protein targets on the same sample. We used a set of antibodies targeting key immune and tumor cell markers- PD1, CD3, CD4, CD8, CD68, FOXP3 and KRT17, along with RNA biomarkers to interrogate the tumor microenvironment (TME) in human FFPE tumor samples. Using a combination of RNA and protein targets, we characterized different cell types such as T cells, macrophages, and tumor cells in the TME. We also developed a novel method for visualizing intercellular interactions between PD1 and PD-L1, offering insights into popular checkpoint mechanisms that are targeted for therapeutic intervention in cancer treatment. The assay offers a powerful technique for visualizing target RNA biomarkers in specific cell-types identified by cell-marker protein expression. This is a valuable tool for multi-omic analysis and accurate interrogation of complex tissues to obtain insights into novel biomarkers and therapeutic targets.

Citation Format: Anushka Dikshit, Sayantani Basak, Vasudha Murlidhar, Ge-Ah Kim, Julia Yu, Sonali Deshpande, Li-Chong Wang, Maithreyan Srinivasan. Interrogating the tumor-immune landscape with a novel automated RNAscope™ assay for multiplexed detection of RNA and protein. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6771.
Abstract 6779: Spatial and single-nucleus transcriptomics of human glioblastoma
Authors: Hao Yue , Baker Angela , Hilbush Brian , Otero Marcos , Streck Chris , Fink Karen L. , Snipes George J. , Mickey Bruce E. , Berens Michael
Published: April 2023

Glioblastoma (GBM) multiforme is the most aggressive type of brain cancer. These lethal brain tumors are characterized by the inter- and intra-tumor molecular heterogeneity and diverse cell plasticity. We sought to interrogate the immune landscape of GBM, tease out the distinct biological and therapeutic niches in GBM and to understand how the tumor microenvironments mediated the heterogeneity of GBM. We have collected six human GBM samples for spatial profiling and single-nucleus RNA sequencing. Multiple sets of spatial gene panels were designed to capture the cell identities (cancer stem cells, astrocytes, oligodendrocytes, microglia, macrophages, endothelial cells, etc.) and the spatially-resolved expression patterns of genes indicative of different functional states. We also aim to find altered neurovascular units by examining the spatial correlation between cells that highly express angiogenesis markers such as VEGFA with tumor-associated macrophages, which could be recruited to the angiogenic niche by GBM tumor cells. From the spatial RNA dataset of the first two samples, we observed close proximity of tumor-associated macrophages and endothelial cells that form the microvasculature. Our preliminary results from the single-nucleus RNA sequencing and spatial transcriptomics of two samples shed light on the complex cell landscape and the dynamic interaction between tumor cells and infiltrating or resident immune cells in the GBM tumor tissue.

Citation Format: Yue Hao, Angela Baker, Brian Hilbush, Marcos Otero, Chris Streck, Karen L. Fink, George J. Snipes, Bruce E. Mickey, Michael Berens. Spatial and single-nucleus transcriptomics of human glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6779.
Abstract 6786: NT-I7 as an adjuvant to DNA neoantigen vaccination enhances and prolongs neoantigen-specific anti-tumor immunity
Authors: Chen Michael Y. , Chen Ina , Supabphol Suangson , Wolfarth Alexandra A. , Martinez Sara F. , Lee Byung Ha , Li Lijin , Zhang Xiuli , Goedgebuure Peter S. , Gillanders William E.
Published: April 2023

Background: IL-7 is an essential cytokine in the development and maintenance of antigen-specific T cells. NT-I7 (efineptakin alfa; NeoImmuneTech, Inc, Rockville, MD), is a long acting IL-7 composed of recombinant human IL-7 (rhIL-7) fused to a hybrid Fc antibody platform that has significantly improved in vivo stability and half-life compared to rhIL-7. DNA cancer neoantigen vaccines are a promising personalized cancer immunotherapy capable of generating strong anti-tumor immunity, but limited by a short-lived neoantigen-specific T cell response. We hypothesize NT-I7 as an adjuvant to a DNA neoantigen vaccine will enhance the magnitude and duration of neoantigen-specific anti-tumor immunity.

Methods: C57BL/6 mice were vaccinated with DNA vaccine encoding neoantigens present in E0771 murine breast cancer model on days 0, 3, and 6. NT-I7 (5 mg/kg) was administered intravenously on day 4 or 13 during T cell expansion or contraction phase respectively. Primary T cell responses to neoantigens were assessed by IFN-γ ELISPOT. Tumor protection was evaluated by inoculating mice with 5×105 E0771 cells subcutaneously after receiving DNA vaccine with or without NT-I7. Duration of neoantigen-specific CD8 T cell immunity was determined by in vivo CFSE killing assay.

Results: NT-I7 administered during the T cell contraction phase following the DNA vaccine increases the magnitude of neoantigen-specific T cell responses on day 20 compared to DNA vaccine alone. DNA vaccination and NT-I7 alone prior to tumor inoculation confers partial protection against tumor growth compared to control while DNA + NT-I7 during contraction phase rejects 100% of tumors. Compared to DNA vaccine alone, DNA vaccine + NT-I7 during contraction phase induces greater neoantigen-specific killing on day 41 (34.6% vs. 11.97%, p=0.03).

Conclusion: NT-I7 as an adjuvant to a DNA neoantigen vaccine increases the magnitude and duration of neoantigen-specific anti-tumor immunity in a murine model. Clinical application of NT-I7 may help overcome immunologic shortcomings of current neoantigen vaccines.

Citation Format: Michael Y. Chen, Ina Chen, Suangson Supabphol, Alexandra A. Wolfarth, Sara F. Martinez, Byung Ha Lee, Lijin Li, Xiuli Zhang, Peter S. Goedgebuure, William E. Gillanders. NT-I7 as an adjuvant to DNA neoantigen vaccination enhances and prolongs neoantigen-specific anti-tumor immunity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6786.
Abstract 6790: The peptide vaccine revived in cancer immunotherpay: a novel peptide vaccine platform for effective cancer immunotherpay
Authors: Kim Dongho , Lee SeungHwan
Published: April 2023

The production of tumor-specific T cells is essential for cancer immunotherapy. Due to the low cost and ease of CMC, peptide vaccines have been suggested as effective immunotherapy for cancer. A variety of peptide vaccines have been designed and tested in clinical trials for decades. However, most clinical trials of peptide vaccines have failed for several reasons. Poor stability of peptides, use of inappropriate adjuvants, lack of co-delivery of peptides and adjuvants, and immunosuppression by the tumor microenvironment. We tried to solve the problems that lead to failure and developed effective platform technologies for them. The first problem was the choice of vaccine adjuvants. Poly IC and its derivatives are known to induce antigen-specific Th1 and CTL responses. Since Th1-type immunity is essential for the elimination of intracellular pathogens or tumors, they may be suitable as the adjuvant for peptide vaccines. Despite several limitations of poly IC and its derivatives, such as high heterogeneity, inconsistent activity, poor stability, and unpredictable in vivo kinetics, they still serve as major adjuvants in numerous clinical trials. A novel and defined TLR3 agonist called NexaVant (NVT) was developed as an alternative to them. NVT induces a stronger anti-cancer efficacy compared to the known TLR agonists through multiple advantages of homogeneity, stability, and quantitative in vivo kinetics. Second, the stability of peptides was dramatically improved by a peptide/adjuvant complex formation. When a cationic peptide domain is introduced into the epitope together with an epitope processing domain, the peptide and adjuvant can form a nanocomplex by a simple charge interaction. And this complex improves the stability of the peptide which leads to improvement of the T cell immunity. Third, suppression of T cell immunity in cancer was mitigated by Treg modulation in the presence of a known chemotherapeutic drug. When this combination therapy of the vaccine and chemical was applied to various animal models, a strong anticancer effect was obtained by increasing T cell immunity and suppressing Treg. The same therapeutic effect was shown in several terminal stage tumor models with strong T cell memory regardless of whether the epitope was self or foreign originated.

Citation Format: Dongho Kim, SeungHwan Lee. The peptide vaccine revived in cancer immunotherpay: a novel peptide vaccine platform for effective cancer immunotherpay [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6790.
Abstract 684: Nanovaccine displaying immunodominant T cell epitopes of fibroblast activation protein is effective against desmoplastic tumors
Authors: Shin Hocheol , Kim Yujin , Jon Sangyong
Published: April 2023

Cancer-associated fibroblasts (CAFs), which are dominant cell types in the tumor microenvironment (TME), support tumor growth by secreting cytokines and forming an extracellular matrix (ECM) that hampers penetration of chemical and biological therapeutics within the tumor and thereby limits their therapeutic efficacy. Here, we report a cancer nanovaccine targeting fibroblast activation protein alpha (FAP)-expressing CAFs as a potential pan-tumor vaccine. We predicted immunodominant FAP-specific epitope peptides and selected two candidate peptides after in vitro and in vivo screening for immunogenicity and antitumor efficacy. Next, we developed a nanoparticle-based vaccine that displays the two selected epitope peptides on the surface of lipid nanoparticles encapsulating CpG adjuvant (FAPPEP-SLNPs). Immunization with one of two FAPPEP-SLNP nanovaccines led to considerable growth inhibition of various tumors, including desmoplastic tumors, by depleting FAP+ CAFs and thereby reducing ECM production in the TME while causing little appreciable adverse effects. Furthermore, when combined with a chemotherapeutic drug, the FAPPEP-SLNP nanovaccine increased drug accumulation and resulted in a synergistic antitumor efficacy far better than that of each corresponding monotherapy. These findings suggest that our FAPPEP-SLNP nanovaccine has potential for use as an “off-the-shelf” pan-tumor vaccine applicable to a variety of tumors and may be a suitable platform for use in various combination therapies.

Citation Format: Hocheol Shin, Yujin Kim, Sangyong Jon. Nanovaccine displaying immunodominant T cell epitopes of fibroblast activation protein is effective against desmoplastic tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 684.
Abstract 700: Induction of cancer-specific T-cell responses in patients immunized with P10s-PADRE vaccine
Authors: Lee John J. , Nounamo Bernice C. , Jousheghany Fariba , Makhoul Issam , Siegel Eric R. , Kieber-Emmons Thomas , Monzavi-Karbassi Behjatolah
Published: April 2023

Introduction: HR+/HER2− breast cancer is the most common form of breast cancer in the United States. HR+/HER2− tumors are known for a low number of tumor-infiltrating lymphocytes (TILs) and considered less immunogenic than other breast cancer subtypes. We have demonstrated that vaccination with P10s-PADRE, a carbohydrate-mimetic-based peptide, cancer vaccine in combination with standard-of-care chemotherapy in HR+/HER2− breast cancer patients led to an increase in TILs and stromal CD3+ T cells. The current study was performed to determine the vaccine specificity and anti-tumor functionality of T cells in treated patients.

Methods: Peripheral blood mononuclear cells (PBMCs) collected at the baseline and after vaccination were used in T-cell assays by multi-color ELISpot, examining Th1, Th2, and cytotoxic responses. PBMCs were also interrogated for the vaccine-induced changes in immune gene expression by next-generation RNA-seq analysis.

Results: We observed a significant increase in IFN-g, but not in IL-5 or IL-10, responses in post-immune PBMCs after stimulation with P10s, P10s-PADRE and polyclonal stimulation of T cells by anti-CD3/CD28 antibodies. Stimulation with cancer cell lysate resulted in a strikingly high IFN-g response in post-immune samples. Determining the trio of IFN-g, GzB, and IL-2 together with CD4/CD8 cell proliferation assays of consequent post vaccination specimens established the dynamics of effector T-cell populations. RNA-seq data clearly distinguished post-treatment samples by the increase in immune cell activation, cytokine response, and antigen presentation.

Conclusions: The data indicate that immunization of HR+/HER2− breast cancer patients with P10s-PADRE in combination with chemotherapy leads to specific activation of T-cells that recognize breast cancer cells. Improving immunogenicity of such immunologically cold tumors could increase the effectiveness of standard therapeutic approaches.

Citation Format: John J. Lee, Bernice C. Nounamo, Fariba Jousheghany, Issam Makhoul, Eric R. Siegel, Thomas Kieber-Emmons, Behjatolah Monzavi-Karbassi. Induction of cancer-specific T-cell responses in patients immunized with P10s-PADRE vaccine [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 700.
Abstract 704: MDSC-targeted TFF2-MSA suppresses tumor growth and increases survival in anti-PD-1 treated MC38 and CT26.wt murine colorectal cancer models
Authors: Daugherty Bruce L.
Published: April 2023

Aims: Myeloid-derived suppressor cells (MDSCs) in the tumor microenvironment are a potential therapeutic target in immune checkpoint cancer therapy, but MDSC-targeted therapies have yet been shown to improve survival. Trefoil factor family 2 (TFF2), a secreted anti-inflammatory peptide, can suppress MDSC expansion and activate tumor immunity in part through agonism of the CXCR4 receptor. The aim of this study is to investigate whether a novel TFF2 - albumin fusion peptide (TFF2-MSA) can improve survival in anti-PD-1 treated syngeneic colorectal cancer (CRC) mouse models.

Methods: Two syngeneic colon carcinoma mouse models were developed using cell lines grafted subcutaneously into mice. MC38 CRC cells were engrafted into C57BL/6 mice while CT26.wt CRC cells were implanted into BALB/C mice We generated a recombinant fusion protein, designated TFF2-MSA, which contains murine TFF2 fused to murine serum albumin (MSA), for the purpose of increasing half-life and reducing dose frequency. Mice subsequently received either TFF2-MSA or anti-PD-1 antibody (clone 29F.1A12) or both, and tumor volume, and survival were measured. At the endpoint, flow cytometry was performed to examine treatment-induced effects on immune profiles.

Results: In the MC38 model, administration of TFF2-MSA suppressed tumor growth (TGI 38%), the combination of TFF2-MSA and anti-PD-1 had an additive effect and suppressed tumor growth dramatically (TGI 74%). The combination also exhibited a survival rate of 90% after 50 days, while vehicle and single TFF2-MSA therapy were 30% and 65%, respectively. The percentage of exhausted CD8+ T cells was markedly reduced in the draining lymph node by the combination treatment, as measured by flow cytometry using antibodies against LAG3, TIM3 and PD-1. In the CT26.wt model, administration of TFF2-MSA alone exhibited little effect, but the combination of anti-PD-1 and TFF2-MSA showed a profound effect. In the CT26.wt model, administration of TFF2-MSA suppressed tumor growth (TGI 17%), anti-PD-1 alone (TGI 43%) and the combination of TFF2-MSA and anti-PD-1 (TGI 54%).

Conclusion: Targeting MDSCs using TFF2-MSA fusion protein synergizes well with PD-1 blockade therapy in advanced and metastatic syngeneic mouse models of colorectal cancer. In a separate abstract, additive effects between TFF2-MSA and anti-PD-1 antibody were also demonstrated in a separate ACKP (Atp4b-Cre; Cdh1-/-; LSL-KrasG12D; Trp53-/-) gastric cancer model, suggesting combination therapy may also be applicable to gastric cancer.

Citation Format: Bruce L. Daugherty. MDSC-targeted TFF2-MSA suppresses tumor growth and increases survival in anti-PD-1 treated MC38 and CT26.wt murine colorectal cancer models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 704.
Abstract 720: Implementation and evaluation of a mental health app with comedy content for women living with advanced cancer
Authors: Rothberg Saranne , Grill Katherine B. , Wheeler Claire
Published: April 2023

Introduction: Metastatic cancer patients report elevated stress levels and unique stressors compared to other adults. This study tested the feasibility and efficacy of a mental health app with comedy content delivered to women living with advanced cancer (WLAC).

Methods: The mental health platform Neolth was used as a self-guided intervention for WLAC, ages 18+ years. WLAC were recruited by The Comedy Cures Foundation through a press release, social media posts, an email newsletter, and a video call for participants on the foundation’s website. No compensation was provided to participants. After using the Neolth platform, which included watching comedy content for eight weeks, researchers evaluated engagement, and stress levels using The Perceived Stress Scale -10 (PSS-10), self-efficacy using The New General Self-Efficacy Scale (GSES), and anxiety and depression using The Hospital Anxiety and Depression Scale (HADS-A and HADS-D).

Results: 54 WLAC (M = 52.2 years, R = 31-74) from 10 countries and 24 states participated by completing the baseline questionnaire. 20.5% identified as BIPOC and 33.0% had previous experience with a mental health app. 57.4% (N=31) completed the study surveys at Week 4 and Week 8. At Week 8, HADS-D scores decreased 18.1%, PSS-10 scores decreased 15.1%, HADS-A scores decreased by 9.7%, and GSES scores increased 7.6%. Participants spent an average of 116 minutes per week on Neolth with an average of 3.15 logins per week. 43.6% of time spent was completing self-guided relaxation practices and 17.2% watching Comedy Cures Foundation videos from cancer survivor Saranne Rothberg. The 30-day retention on Neolth was 100%, with 60-day retention 83%.

Conclusion: This study demonstrated the ability of a mental health app with comedy content to engage and support the mental health of WLAC, presenting a cost-effective intervention. Further examination with a larger sample size is needed to conduct multivariate analyses for enhanced understanding of the role of mobile apps and comedy content in reducing stress, anxiety, and depression for WLAC.

Citation Format: Saranne Rothberg, Katherine B. Grill, Claire Wheeler. Implementation and evaluation of a mental health app with comedy content for women living with advanced cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 720.