bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 5357: The tumor-intrinsic RNA binding protein HuR is essential for anti-tumor immunity in PDAC
Authors: Guo Yifei , Finan Jennifer M. , Bartlett Alexandra Q. , Brody Jonathan R. , Eil Robert 
Published: March 2024

Abstract
Immunotherapies have shown limited effectiveness in pancreatic ductal adenocarcinoma (PDAC), despite having success in other cancers. The RNA-binding protein HuR is known to play a critical role in the oncogenesis of PDAC by regulating key mRNA transcripts. Our lab has shown that tumor-intrinsic HuR is overexpressed in PDAC and regulates the tumor microenvironment composition, altering multiple tumor cytokines to release. Thus, we hypothesized that HuR plays a role in immune evasion of PDAC. We disrupted the locus encoding HuR (Elavl1) using CRISPR Cas9 in Kras-p53 mutant-driven (KPC) murine PDAC to assess its function in tumor immune evasion. Here, we report that HuR, a known pro-survival factor for PDAC, has a role in tumor immune evasion by suppressing T cell infiltration and T cell activation. Specifically, HuR-knockout (KO) KPC tumors grew slower compared to KPC wildtype (WT) tumors in an orthotopically implanted model (p-value &lt; 0.0001), even though human PDAC cell lines with HuR-WT and HuR-KO grew at the same rate in NRG mice (in an immune-compromised environment). Accordingly, HuR-KO tumors had more T cell infiltration and activated T cells compared to HuR-WT tumors (p-value = 0.0047). Importantly, T cell depletion (both CD4+ and CD8+) partially rescued the size of HuR-KO tumors. Next, we rescued the expression of HuR in the HuR-KO cell line, and the re-expression partially rescued the tumor size in vivo. This observation validates a HuR-mediated dependent mechanism. Collectively, these data support the hypothesis that HuR suppresses T cell activation and prevents T cells from infiltrating into the PDAC microenvironment, leading to PDAC immune evasion. Ongoing experiments will transduce KPC cell lines with ovalbumin (OVA) antigen, which will selectively activate CD8+ OT-I T cells through their transgenic TCR, to measure the ability of KPC HuR-WT or HuR-KO OVA cells in directly activating CD8+ OT-I T cells. We will also investigate HuR's impact on immune cells' cytokine release and how that will impact the cytotoxicity of T cells. These findings support the ongoing concept that HuR plays an important pro-survival role in PDAC in vivo, and targeting strategies against HuR being developed (e.g., siHuR nano-therapies and small molecule inhibitors) could potentially enhance PDAC sensitivity to immune-based anti-cancer therapies, such as checkpoint blockade and T cell transfer.
Citation Format: Yifei Guo, Jennifer M. Finan, Alexandra Q. Bartlett, Jonathan R. Brody, Robert Eil. The tumor-intrinsic RNA binding protein HuR is essential for anti-tumor immunity in PDAC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5357.
Abstract 5360: Relief of chromosomal instability-induced cGAS-STING signaling sensitizes STK11-mutant non-small cell lung cancer to immune checkpoint blockade
Authors: Caprio Lindsay A. , Hong Christy , Amin Amit D. , Tagore Somnath , Duran Mercedes , Rogava Meri , Cai Luke , Ebel Leon , Melms Johannes , Hibshoosh Hanina , Bakhoum Samuel , Izar Benjamin 
Published: March 2024

Abstract
Non-small cell lung cancers (NSCLCs) harboring deletions or inactivating mutations in STK11 (encoding LKB1) are associated with poor prognosis and immune evasion, but the underlying mechanisms are poorly understood. Through integrative analyses of &gt;10,000 molecular profiles from public data sources and an additional ~15,000 new patient data profiles, we find identify STK11-deficient NSCLC as an archetypical chromosomally unstable tumor. Using high-content imaging, we show that both human and murine STK11-mutant models have a higher rate of micronuclei and chromosome mis-segregation events, confirming their high degree of chromosomal instability (CIN). We show that CIN-induced tonic activation of the cGAS-STING pathway results in impaired type I interferon expression, thus, turning the physiological function of this pathway on its head. We show that temporary relief of tonic CIN-induced signaling reprogrammed cancer cells towards production of type I interferons. We achieved this through orthogonal routes, including genetic suppression of CIN by overexpression of mitotic centromere-associated kinesin (MCAK), rescue of wild-type STK11 (but not its kinase-dead) allele, genetic deletion or pharmacological inhibition of cGAS. Relief through any of these approaches re-sensitized cells to acute STING agonism with its endogenous ligand (cGAMP) or pharmacological stimulation. Using otherwise isogenic, syngeneic KRAS-mutant Stk11/Lkb1-/- (KL) and KRAS-mutant p53 mutant (KP) murine models, we show that cGAS KO sensitized otherwise highly resistant KL models to immune checkpoint blockade (ICB), while an increase in CIN (through overexpression of dominant-negative MCAK) in KP conferred resistance in this otherwise ICB-sensitive model. In summary, we define STK11-mutant as archetypical chromosomally unstable form of NSCLC, provide mechanistic basis that correlates with poor clinical outcomes, and demonstrate how relief of tonic CIN-induced changes may be therapeutically leveraged.
Citation Format: Lindsay A. Caprio, Christy Hong, Amit D. Amin, Somnath Tagore, Mercedes Duran, Meri Rogava, Luke Cai, Leon Ebel, Johannes Melms, Hanina Hibshoosh, Samuel Bakhoum, Benjamin Izar. Relief of chromosomal instability-induced cGAS-STING signaling sensitizes STK11-mutant non-small cell lung cancer to immune checkpoint blockade [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5360.
Abstract 5361: Aberrant glycosylation in mPDAC is associated with increased epithelial-mesenchymal transition and recruitment of immunosuppressive cells
Authors: Brookens Shawna , Degaramo David , Wilson Kiesha , Obregon Wilder Condori , Nagarkatti Prakash , Nagarkatti Mitzi , Posey Jr. Avery 
Published: March 2024

Abstract
The tumor-associated glycan Tn antigen (GalNAc-α-O-Ser/Thr) is associated with poor prognosis in various solid tumors. However, the mechanisms that Tn antigen promotes tumorigenesis are incompletely understood. Here, we generated Tn antigen-expressing murine pancreatic ductal adenocarcinoma (mPDAC) tumor cell lines through CRISPR/Cas9-mediated knockout of the C1galt1c1 gene. Tn antigen expressing mPDAC cell lines exhibited increased in vitro proliferation and migration compared to parental controls. RNA sequencing revealed that loss of C1galt1c1 in mPDAC cells correlated with increased expression of genes associated with epithelial-mesenchymal transition, myeloid recruitment, and extracellular matrix deposition. Consequently, knock-down of elevated genes using CRISPR interference dampened in vitro cell proliferation of C1galt1c1 knockout mPDAC cells to the growth rate of parental controls. Additionally, C1galt1c1 knockout mPDAC cells implanted into mice led to accelerated tumor growth and increased tumor infiltration of myeloid-derived suppressor cells and neutrophils as determined by flow cytometry and scRNAseq. Interestingly, surface expression of a binding partner of Tn antigen, macrophage galactose-type lectin 2 (Mgl2), was altered in the immune infiltrate of C1galt1c1 knockout tumors suggesting a role for the Mgl2-Tn interaction in tumor progression. Mgl2-deficient mice exhibit increased T effector cells in the draining lymph nodes of tumors highlighting a potential mechanism for promoting the influx of immune cells in ordinarily cold tumors. Together, our data indicate that truncated O-glycans expressed commonly on tumor cells promotes tumorigenesis through creating an immunosuppressive microenvironment in mPDAC.
Citation Format: Shawna Brookens, David Degaramo, Kiesha Wilson, Wilder Condori Obregon, Prakash Nagarkatti, Mitzi Nagarkatti, Avery Posey Jr.. Aberrant glycosylation in mPDAC is associated with increased epithelial-mesenchymal transition and recruitment of immunosuppressive cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5361.
Abstract 5385: Synthetic disulfide derivative of vitamin B1, fursultiamine, prevents VEGF-induced angiogenesis
Authors: Tran Sabrina , Frost Zachary , Ramana Kota 
Published: March 2024

Abstract
Angiogenesis is a process in which new blood vessels are formed from the existing blood vessels required to supply nutrients and oxygen to various tissues. Angiogenesis plays a significant role in the growth and spread of many cancers, and several anti-angiogenic agents act as chemotherapeutic agents. Recent studies have shown that fursultiamine (thiamine tetrahydrofurfuryl disulfide), a lipid-soluble synthetic disulfide derivative of thiamine, possesses viable antineoplastic and antiviral effects. However, its role in preventing angiogenesis is not known. We hypothesize that fursultiamine, with its potent antioxidative actions, prevents VEGF-induced angiogenesis in vitro and in vivo. Human umbilical vein endothelial cells (HUVECs) were treated with VEGF in the absence and presence of fursultiamine (0-100 uM) in a time and dose-dependent manner. Cell viability was determined by MTT assay and in vitro angiogenesis by tube formation assays. The expression of various pro-angiogenic, anti-angiogenic and inflammatory markers will be determined by specific antibody arrays. Our results indicate that fursultiamine prevents VEGF-induced endothelial cell growth in a dose-dependent manner. Further, fursultiamine prevents the in vitro tube formation as determined tube formation assays. Further, fursultiamine also regulated the VEGF-induced expression of various angiogenic markers such as VEGF, PDGF, EGF, Ang1, Ang2, angiogenin, and FGF, inflammatory markers such IL-1b, GM-CSF, TGF-b, MMPs, and others such as TIMPs, PTX3 and CF-III. Based on our in vitro data, we suggest that fursultiamine could prevent VEGF-induced angiogenesis, and this compound as a potent anti-angiogenic agent that could prevent cancer growth and metastasis.
Citation Format: Sabrina Tran, Zachary Frost, Kota Ramana. Synthetic disulfide derivative of vitamin B1, fursultiamine, prevents VEGF-induced angiogenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5385.
Abstract 5409: Phosphorylated focal adhesion kinase by mild reduction of cell surface proteins inhibits integrin α5β1-dependent patient- derived cancer cell migration and invasion
Authors: Kim Joo Hyun , Anggradita Laurensia D. , Hur Sung Sik , Park Jae Hong , Kim Sang-Heon , Ban Myung Jin , Hwang Yongsung 
Published: March 2024

Abstract
Although head and neck squamous cell carcinomas (HNSCCs), including tongue, vocal cord, and buccal cancers, are one of the most common cancers worldwide with a mortality rate of more than 40%, there have been no solid standard biomarkers for effectively diagnosing HNSCCs at early stages and no effective protocols available to support in vitro expansion of HNSCC cells. To establish a cell culture method to support in vitro self-renewal of HNSCC cells, patient-derived tumor was enzymatically digested, and the tongue cancer epithelial cells were seeded onto feeder cells with the Rho kinase inhibitor (Y-27632). Additionally, to test our hypothesis that free thiol groups in the cells, generated by a mild reduction of cell surface proteins using the reducing agent tris(2-carboxyethyl) phosphine hydrochloride (TCEP), would modulate cancer cell adhesion and migration, we assessed the expression levels of integrins, focal adhesion kinase (FAK), and phosphorylated FAK (pFAK) of tongue cancer epithelial cells cultured on both soft and rigid polyacrylamide (PAAm) hydrogel-based cell culture substrates. Patient-derived tongue cancer epithelial cells exhibited self-renewal ability and maintained cancerous phenotypes, with high expressions of P53, Ki67, E-cadherin, CD44, and AHDH1A1. Treatment with the reducing agent (TCEP) increased the degree of cell adhesion through the significantly upregulated integrin α5β1-mediated phosphorylation of FAK, resulting in inhibited single-cell and collective cell migration as well as invasion. Additionally, when these cells were cultured on stiff PAAm hydrogels mimicking the tumor microenvironment, the cells exhibited accelerated cell migration behaviors, compared to cells on soft hydrogels. These results highlight the synergetic contributions of feeder cells and Rho kinase inhibitor to support long-term self-renewal of tongue cancer patient-derived epithelial cells.
Citation Format: Joo Hyun Kim, Laurensia D. Anggradita, Sung Sik Hur, Jae Hong Park, Sang-Heon Kim, Myung Jin Ban, Yongsung Hwang. Phosphorylated focal adhesion kinase by mild reduction of cell surface proteins inhibits integrin α5β1-dependent patient- derived cancer cell migration and invasion [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5409.
Abstract 5414: BDNF/TrKB signaling may lead to higher incidence of perineural invasion in men with prostate cancer
Authors: Edwards Gabrielle Joy , Odero-Marah Valerie 
Published: March 2024

Abstract
Perineural invasion (PNI) is a crucial mechanism facilitating prostate cancer metastasis. PNI encompasses perineural, circumferential, and intraneural invasion, with cancer cells closely interacting with nerves. Evidence suggests that cancer cells utilize the nervous system for metastasis through signaling pathways. PNI is associated with poor prognoses in various cancers, but its role in prostate cancer remains unclear. PCa primarily metastasizes through systemic routes, such as lymphatic and circulatory systems. Metastasizing cancer cells undergo epithelial-mesenchymal transition (EMT), enhancing their motility. SNAIL1, a transcriptional repressor, induces EMT and promotes cancer cell migration, including towards nerves, termed neurite outgrowth. Neurite outgrowth involves intricate signaling between tumor cells and nerves, possibly facilitating cancer cell infiltration into nerve sheaths and PNI. Our lab has shown SNAIL1 in interactions with neurotrophic factors like Brain-Derived Neurotrophic Factor (BDNF) and Tyrosine Kinase Receptor Beta (TrkB), modulating cancer cell behavior. TrkB is overexpressed in various cancers, while BDNF signaling contributes to EMT via the Twist-Snail axis. BDNF may also play a role in PNI pathogenesis. Our hypothesis posits the BDNF-TrkB axis drives aggressive prostate cancer and PNI. This study employed prostate cancer cell lines for comprehensive analysis. We assessed BDNF expression in different cell lines, particularly those with high Snail levels, and analyzed BDNF transcript levels via real-time quantitative PCR following RNA extraction and reverse transcription. We explored whether BDNF overexpression enhanced cancer cell migration towards nerves, employing migration assays. Our findings indicated heightened migration in BDNF-high cell lines, C42, PC3, and MDA-2b, compared to BDNF knockdown cells. Additionally, a TrkB inhibitor, K252a, attenuated migration due to BDNF-induced TrkB phosphorylation. Our study establishes that BDNF/TrkB signaling promotes prostate cancer cell migration towards nerves, a phenomenon reversible with K252a, offering a potential strategy to impede prostate cancer progression and metastasis.
Citation Format: Gabrielle Joy Edwards, Valerie Odero-Marah. BDNF/TrKB signaling may lead to higher incidence of perineural invasion in men with prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5414.
Abstract 5442: Terthighcells: key players in salivary gland homeostasis and regeneration after radiation therapy in adult mice
Authors: Guan Li , Viswanathan Vignesh , V Sivakamasundari , Cao Hongbin , Jiang Yuyan , Zhao Junfei , Colburg Deana R. , Neuhoefer Patrick T. , Xu Yu , Laseinde Eyiwunmi E. , Artandi Steven , Le Quynh-Thu 
Published: March 2024

Abstract
Salivary gland homeostasis and regeneration post-radiotherapy depend significantly on stem/progenitor cells. However, the lineage of SMG progenitor cells is not as well defined as in other normal organs, and better understanding of this population would be important for their future clinical application for tissue regeneration. Using a mouse strain expressing regulated CreERT2 recombinase from the endogenous Tert locus, we identify a distinct Terthigh cell population that are located in the ductal region throughout the submandibular gland (SMG), express ASCL3 (another progenitor cell marker) and can give rise to ductal cells during homeostasis. In contrast, Terthigh cells are found to repopulate both ductal and acinar cells at one year of tracing after radiotherapy. Terthigh cells from adult SMG retain self-renewal capacity when subjected in vitro culture, are resistant to radiation cell kill, and display enhanced proliferative activity post-radiation. Similarly, primary human SMG cells with high Tert expression display enhanced cell survival after radiotherapy. RNA sequencing reveals upregulation of the cell cycling and oxidative stress response pathways these cells after radiation. Mechanistically, Tert appears to modulate cell survival and ROS level in SMG spheres following radiation damage. Collectively, these data suggest that Terthigh cells constitute a novel subset of SMG progenitor cells located throughout the ductal region of the gland that can help to repopulate both ductal and acinar cells after RT damage.
Citation Format: Li Guan, Vignesh Viswanathan, Sivakamasundari V, Hongbin Cao, Yuyan Jiang, Junfei Zhao, Deana R. Colburg, Patrick T. Neuhoefer, Yu Xu, Eyiwunmi E. Laseinde, Steven Artandi, Quynh-Thu Le. Terthighcells: key players in salivary gland homeostasis and regeneration after radiation therapy in adult mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5442.
Abstract 5464: Galectin-3 expression in Ewing sarcoma: Modulation of the immune microenvironment in an immunocompetent model
Authors: Maharjan Yunash , Dey Sreya , Mukherjee Elina , Daley Jessica , Bailey Kelly M. 
Published: March 2024

Abstract
Objective: Ewing sarcoma is an aggressive cancer of adolescents. Patients with metastatic Ewing sarcoma often receive radiation as part of their treatment protocol. We have demonstrated that both Ewing tumor cells and T cells infiltrating Ewing tumors express Galectin-3 (Gal3), an immunosuppressive protein in the tumor microenvironment. Here, we utilize an immunocompetent, humanized mouse model of Ewing sarcoma to investigate the role of Galectin-3 in the Ewing tumor immune microenvironment both at baseline and following radiation. Specifically, we sought to determine the influence of Galectin-3 on post-radiation inflammation in Ewing sarcoma.
Methods: Human Ewing cells -/+ Gal3 expression were generated using CRISPR/Cas 9 technology. Cells -/+ Gal3 were orthotopically injected into humanized mice and allowed to established tumors over ~3 weeks. Tumors were then treated with radiation (or no radiation controls). To also address immune cell expression of Gal3, galectin inhibitors were utilized. Tumors were analyzed by bulk RNA sequencing and flow cytometry analysis (Cytek Aurora) for human CD45, CD3, CD4, CD20, CD8, CD56, CD14, CD16, etc. Peripheral blood controls were also collected and analyzed to ensure consistent baseline immune reconstitution.
Results: CHLA10 and TC32 Ewing sarcoma cell lines both demonstrate Gal3 expression at baseline by western blot. CRISPR/Cas 9 knock-out of Gal3 in both cell lines showed successful knock down. Impact on growth and sensitivity to radiation in vitro was assessed by live cell Incucyte assays. Tumors in humanized mice were established utilizing these cells (or Gal3 expressing non-targeting controls) and changes in the post-radiation transcriptional profiles were assessed. Immune cells infiltrating these tumors were also quantified. Ongoing work focuses on additional characterization of these tumor infiltrating immune cell populations following radiation therapy and the impact of broader galectin inhibition on this effect.
Conclusion: This work contributes to the understanding of radiation-induced tumor inflammatory responses in Ewing sarcoma by defining the role of tumor and T cell galectin-3 expression inn Ewing immunobiology. Next steps will explore translational opportunities based on these findings.
Citation Format: Yunash Maharjan, Sreya Dey, Elina Mukherjee, Jessica Daley, Kelly M. Bailey. Galectin-3 expression in Ewing sarcoma: Modulation of the immune microenvironment in an immunocompetent model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5464.