bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5133: Gastric cancer carrying FAT4 mutations associated with favorable prognosis in comparison to wild-type: Results from Real-World Cohorts
Authors: Wang Shu , Wang Haoyuan , Ma Yuxuan , Wang Yuhao , Zhao Yan , Peng Chaosheng , Duan Weiming , Zhao Feilong , Yang Jianjun
Published: March 2024

Introduction: Gastric cancer (GC) is a complex and heterogeneous disease with variable clinical outcomes. Identifying prognostic factors that can reliably predict patient outcomes is crucial for personalized treatment strategies. In this study, we aimed to investigate the impact of mutations in the FAT4 gene as potential prognostic factors in gastric cancer.

Methods: We conducted a comprehensive analysis of genomic data from a cohort of 236 gastric cancer patients to identify mutations in the FAT4 gene and validated it using the TCGA cohort. The mutational landscape of FAT4 was analyzed using next-generation sequencing (NGS) techniques. Clinical data, including patient demographics, tumor characteristics, and survival outcomes, were collected and correlated with the presence of FAT4 cadherin mutations.

Results: In the real-world cohort, the occurrence of mutations of FAT4 was 19.1% (45/236), while in the TCGA cohort, it was 21.0% (89/423). Specifically, the mutation rates in the single cadherin functional domain of FAT4 were 10.2% (24/236) in the real-world cohort and 8.0% (34/423) in the TCGA cohort. The mutation rates for multiple cadherin sites were 2.5% (6/236) and 2.1% (9/423) in the real-world and TCGA cohorts, respectively. Survival analysis revealed that patients with FAT4 mutations had a significantly better prognosis compared to those with wild-type FAT4 (p=0.0357). Patients with multiple cadherin mutations had a better prognosis compared to those with single cadherin mutations in real-world cohorts (p=0.0651). No significant difference was observed in the TCGA cohort between single and multiple cadherin mutations (p = 0.2003), although FAT4 mutations exhibited a significant improvement in prognosis compared to wild-type patients in the TCGA cohort (p = 0.0226).

Conclusion: Our findings indicate that FAT4 mutations confer a favorable prognosis in gastric cancer patients. The presence of FAT4 mutations was associated with improved survival compared to patients with wild-type FAT4. These findings underscore the potential value of FAT4 mutation status as a prognostic factor, guiding personalized treatment approaches for individuals with gastric cancer.

Citation Format: Shu Wang, Haoyuan Wang, Yuxuan Ma, Yuhao Wang, Yan Zhao, Chaosheng Peng, Weiming Duan, Feilong Zhao, Jianjun Yang. Gastric cancer carrying FAT4 mutations associated with favorable prognosis in comparison to wild-type: Results from Real-World Cohorts [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 5133.
Abstract 519: Targeting MYC as a novel therapeutic strategy for an epigenetic-driven cancer: NUT Carcinoma
Authors: Escudero-Iriarte Carmen , Castro Joel , Beniavides-Puy Iker , Tissera Natalia S. , Querol-Paños Jessica , Agustí Irene , Whitfield Jonathan R. , Vieito Maria , Nonell Lara , Macarulla Teresa , Braña Irene , Soucek Laura , Tian Tian V.
Published: March 2024

Epigenetic dysregulation is widespread in cancer, playing a pivotal role in shaping cell function and contributing to the process of oncogenic transformation. NUT Carcinoma (NC) is an exceptionally rare and aggressive cancer lacking effective treatment, with a dismal prognosis - NC patients typically survive less than seven months after the initial diagnosis. NC is characterized by the presence of chromosomal rearrangements involving the gene encoding for the testis-specific NUT protein and a ubiquitous gene encoding an epigenetic regulator, BRD4 in most cases. Previous studies have demonstrated the role of the BRD4-NUT fusion protein in generating clusters of acetylated histones, namely “megadomains,” throughout NC cell chromatin. These NUT-containing fusion proteins are involved in NC oncogenesis by altering the epigenetic and transcriptional landscapes, promoting cell proliferation while impeding cell differentiation. Indeed, several downstream targets, including P63, SOX2, and MYC, have been identified to be modulated by NUT fusion proteins, independently of the fusion partners. This study focuses on a novel therapeutic approach targeting MYC for NC treatment. We conducted a comprehensive preclinical study of OMO-103, a MYC inhibitor currently undergoing clinical evaluation, using various NC patient-derived cell lines. Through cell viability assays, cell cytometry, western blotting, RNA-seq data analysis in vitro, as well as in vivo drug efficacy evaluation in NC xenografts, we delved into the effects of OMO-103 on NC cells. Our findings reveal that OMO-103 effectively inhibits NC cell growth both in vitro and in vivo. It induces cell apoptosis, differentiation, and cell cycle arrest in vitro, and when tested in xenografts in vivo, OMO-103 reduces tumor growth and enhances mouse survival, particularly when combined with a chemotherapy regimen. This study presents a promising therapeutic strategy for an incurable and aggressive cancer type.

Citation Format: Carmen Escudero-Iriarte, Joel Castro, Iker Beniavides-Puy, Natalia S. Tissera, Jessica Querol-Paños, Irene Agustí, Jonathan R. Whitfield, Maria Vieito, Lara Nonell, Teresa Macarulla, Irene Braña, Laura Soucek, Tian V. Tian. Targeting MYC as a novel therapeutic strategy for an epigenetic-driven cancer: NUT Carcinoma [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 519.
Abstract 5333: NeoMab: A novel platform for fully human therapeutic antibody development
Authors: Zhang Mingkun , Ju Cunxiang , Li Song , Peng Junchao , Zhao Jing , Gao Xiang
Published: March 2024

Antibodies and antibody containing therapeutics, such as multivalent antibodies, chimeric antigen receptors (CARs), and antibody directed conjugates (ADCs), have been proven to be highly prominent in cancer treatment. However, challenges such as immunogenicity stemming from non-human or unnatural sequences and limitations in preclinical animal study systems still impede the rapid development of antibody drugs.

To overcome these hurdles, GemPharmatech has created a novel antibody gene humanized model, the NeoMab mouse, to develop fully human antibodies. The NeoMab model was established via large genomic fragment knock-in technology, retaining native mouse constant region encoding genes and regulatory elements, while incorporating human variable gene repertoires into the endogenous loci. Developed in the BALB/c background, the NeoMab mouse carries fully functional MHC molecules, potentially enhancing antigen presentation. These mice sustain a competent immune system with a B cell development and maturation pattern, immune cell profile, and serum immunoglobulin levels comparable to those of BALB/c mice.

NeoMab mice exhibit a robust humoral immune response, with a rapid increase in antigen-specific serum titers upon immunization using different antigens, such as recombined protein, plasmids, and overexpressing cell lines. Utilizing human V(D)J genes to encode immunoglobulins at a human-like frequency and diversity, antibodies derived from NeoMab mice demonstrate affinity and functional activity comparable to, or even surpassing, FDA-approved drugs.

In conclusion, the NeoMab mouse model in the BALB/c background has been rigorously validated to elicit a robust response to specific antigen immunization, producing antibodies with high affinity, diversity, and functional activity. GemPharmatech's extensive drug-target gene humanized mouse library (comprising over 800 targets) and diverse disease models in oncology and other fields facilitate a seamless connection between in vitro antibody screening and in vivo animal studies. The integration of NeoMab, target humanization animals, and disease models enables GemPharmatech to provide an integrated solution, reducing time and costs while elevating the quality of antibody discovery in the field.

Citation Format: Mingkun Zhang, Cunxiang Ju, Song Li, Junchao Peng, Jing Zhao, Xiang Gao. NeoMab: A novel platform for fully human therapeutic antibody development [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 5333.
Abstract 5351: Tumor PKC-Delta induces immune exclusion in non-small cell lung cancer
Authors: Fan Xing Xing
Published: March 2024

The recruitment of a sufficient number of immune cells to induce an inflamed tumor microenvironment (TME) is a prerequisite for effective response to cancer immunotherapy. The immunological phenotypes in the TME of EGFR-mutated lung cancer were characterized as non-inflamed, for which immunotherapy is largely ineffective. To orchestrate host immunity against lung tumors, we proposed that PKCδ, a gatekeeper of immune homeostasis with kinase activity, is responsible for the un-inflamed phenotype in EGFR-mutated lung tumors. It promotes tumor progression by stimulating extracellular matrix (ECM) and PD-L1 expression which leads to immune exclusion and assists cancer cell escape from T cell surveillance. Ablation of PKCδ enhances the intratumoral penetration of T cells and suppresses the growth of tumors. Furthermore, blocking PKCδ significantly sensitizes the tumor to immune checkpoint blockade (ICB) therapy (αPD-1) in vitro and in vivo models. These findings revealed that PKCδ is a critical switch to induce inflamed tumors and consequently enhances the efficacy of ICB therapy in EGFR-mutated lung cancer. This opens a new avenue for applying immunotherapy against recalcitrant tumors.

This work was funded by the FDCT project grant to Dr. Xing-Xing Fan (Grant no. 0058/2020/A2).

Citation Format: Xing Xing Fan. Tumor PKC-Delta induces immune exclusion in non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5351.
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

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 < 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

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 >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

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

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

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

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

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

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.
Abstract 5466: In vivo characterization of neuroblastoma intratumoral heterogeneity
Authors: Squires Willow R. , Weiss Alex , Cohen-Gogo Sarah , Shlien Adam , Kaplan David , Irwin Meredith S. , Hayes Madeline N.
Published: March 2024

Background: Neuroblastoma is a pediatric solid tumor that arises from neural crest-derived progenitor cells of the peripheral sympathetic nervous system (PSNS). Neuroblastoma patients display a significant level of genetic and phenotypic heterogeneity, with amplification of the MYCN oncogene associated with poor clinical outcomes. To better understand underlying genetic mechanisms associated with aggressive neuroblastoma, our group incorporated patient-relevant loss-of-function mutations into the established MYCN-driven zebrafish model of neuroblastoma (Tg(dbh:EGFP-MYCN)), which resulted in increased tumor penetrance and a highly metastatic phenotype.

Aims & Methods: We aimed to investigate metastases-associated intratumoral heterogeneity in vivo using our patient-relevant metastatic zebrafish models, with functional validations performed using human neuroblastoma cell lines.

Results: Single-cell RNA sequencing of metastatic zebrafish neuroblastoma tumors revealed intra-tumor cell heterogeneity, with a subset of cells highly expressing markers of more differentiated adrenergic-like cell fates (th, dbh, phox2a) while others enriched for markers of less differentiated mesenchymal-like progenitor cells (prrx1a, vim, fn1a). Differential cell labeling in zebrafish neuroblastoma suggests distinct tumor cell populations for follow-up validation and characterization throughout metastatic progression.

Conclusion: Single-cell RNA sequencing of zebrafish metastatic neuroblastoma showed evidence of intratumoral heterogeneity that warrants further investigation. We are characterizing neuroblastoma intratumoral heterogeneity in our in vivo metastatic zebrafish models to examine the association between neuroblastoma tumor composition and metastatic potential. Altogether, this work aims to improve our understanding of the evolution of tumor cell heterogeneity associated with neuroblastoma metastasis and uncover novel therapeutic opportunities to improve patient outcomes.

Citation Format: Willow R. Squires, Alex Weiss, Sarah Cohen-Gogo, Adam Shlien, David Kaplan, Meredith S. Irwin, Madeline N. Hayes. In vivo characterization of neuroblastoma intratumoral heterogeneity [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 5466.
Abstract 548: Exploiting pronounced selection pressure from therapeutic bottlenecks to identify orthogonal immunotherapy targets
Authors: Fisk J. Nic , Townsend Jeffrey P.
Published: March 2024

Evolutionary processes play a crucial role in the development of cancer, where tumor cells continuously adapt, leading to the dominance of cell populations over their non-tumor counterparts, evading treatment and ultimately resulting in death. Effective cancer therapies induce significant and targeted selection pressures. During and in response to the induced bottleneck by therapy, the heterogeneous cancer cell population either diminishes or evolves, causing a subsequent selective sweep and the emergence of cells with resistance traits. However, this bottleneck phase presents a unique opportunity to predictably reduce the diversity of tumor cells. In this context, we propose a framework to quantify the selection on variants before, during, and after the therapeutic bottleneck, enhancing our understanding of the mechanisms underlying the acquisition of therapeutic resistance. Furthermore, we combine measures of selection intensity with the prediction of neoantigens in a patient cohort to identify potential alternative targets for immunotherapy. The outcome is a strategy that exploits the predictability introduced by the primary therapeutic bottleneck to eliminate the remaining tumor cell population. Finally, we illustrate the efficacy of this strategy in the context of several cancer types and empirically identify potential cancer type specific and pan-cancer immunotherapy targets orthogonal to primary, first-line therapies.

Citation Format: J. Nic Fisk, Jeffrey P. Townsend. Exploiting pronounced selection pressure from therapeutic bottlenecks to identify orthogonal immunotherapy targets [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 548.
Abstract 551: Investigation of the antipoliferative effect of the Xylopia Aethiopicaextract in triple-negative breast cancer cells
Authors: Soni Shailvi , Modi Shail Rakesh , Andey Terrick
Published: March 2024

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer and has very limited treatment options. Xylopia Aethiopica (XA) is a common spice that is widely used in the regions of central and western Africa. It is known to have various pharmacological properties, one of which is anti-inflammatory activity. The anti-inflammatory effect may portend antiproliferative activity. We hypothesized that the extract of XA will exert antiproliferative activity against TNBC cells. The study aimed to establish the molecular mechanism underlying the antiproliferative activity of XA extract (XAE) against TNBC. The dried fruits of XA were crushed in a mixer and macerated using diethyl ether for 72 h. The macerate was subjected to vacuum and rotary evaporation to remove the organic solvent, and a stock solution was prepared in dimethyl sulfoxide (DMSO). Assessment of the efficacy of XAE was performed using serial dilutions (100 µg/ml, 50 µg/ml, 10 µg/ml, 5 µg/ml, and 1µg/ml) of the XAE stock solution, followed by in vitro testing against two TNBC cell lines (MDA-MB-231, and MDA-MB-468 cells). The cytotoxic effect of the XAE was then measured using the resazurin dye assay. XAE resulted in a concentration-dependent cell death in both cell lines. At the highest concentration (100 µg/ml), XAE induced cytotoxic cell death of 89% and 91% in MDAMB231 and MDAMB468 cells, respectively. This was consistent with IC50 values of 32.95 ± 1.32 µg/ml (MDAMB231) and 20.83 ± 1.05 µg/ml (MDAMB468). At the molecular level, western blot analysis of mitogenic markers associated with MAPK oncogenic signaling pathway demonstrated the inhibition of EGFR and AKT protein levels after a 48-h treatment. Acridine orange-ethidium bromide (AO/EB) staining showed a concentration-dependent induction of apoptosis in both cell lines. Flow cytometric analysis was performed to quantify the apoptotic cells. A significant increase of apoptotic cells was observed in treatment groups as compared to control after 72 h. Apoptotic induction was associated with increased p53 protein levels after 48 h treatment compared to control. The study results underscore the anticancer effects of XAE in TNBC cells mediated through induction of apoptosis.

Citation Format: Shailvi Soni, Shail Rakesh Modi, Terrick Andey. Investigation of the antipoliferative effect of the Xylopia Aethiopicaextract in triple-negative breast cancer 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 551.
Abstract 5548: Cannabidiol enhances efficacy of atezolizumab via upregulation of PD-L1 expression by cGAS-STING pathway in triple negative breast cancer cells
Authors: Kim Bu Gyeom , Kim Bo Ram , Kim Dae Yeong , Yun Hyemi , Kim Dayoung , Kim Woo Young , Kang Sanghee , Lee Sun Il , Oh Sang Cheul
Published: March 2024

The current treatment for patients with triple negative breast cancer (TNBC) relies on cytotoxic therapy. Currently, atezolizumab and chemotherapy can be combined in patients with TNBC, but this approach is not effective for all patients with low reactivity to atezolizumab. As there is a lack of alternative treatment options, new anti-cancer drugs are urgently needed to enhance atezolizumab reactivity against TNBC. Recent strategies have focused on regulating the expression of programmed death-ligand 1 (PD-L1) or enhancing immune response activation by combining anti-cancer drugs with immune checkpoint inhibitors (ICIs). Cannabidiol (CBD), a cannabinoid component derived from the cannabis plant, has been reported to have anti-cancer therapeutic potential because of its capacity to induce apoptotic cell death in tumor cells while avoiding cytotoxicity in normal cells. Previous studies have demonstrated the effects of CBD on apoptosis in various types of cancer cells. However, the potential role of CBD as an immune modulator in the regulation of PD-L1 expression and the anti-cancer immune response remains to be explored. In this study, we found that CBD stimulated PD-L1 expression in TNBC cells, which significantly induced CBD-mediated cGAS-STING pathway activation. Taken together, we demonstrated that the combination of CBD and anti-PD-L1 antibody enhances the anti-cancer immune response in vitro and in vivo experiments. Our findings identified the mechanism of PD-L1 regulation by CBD in TNBC cells and suggested that CBD could be a potential candidate for the development of new combinatorial strategies with ICIs in TNBC patients.

Citation Format: Bu Gyeom Kim, Bo Ram Kim, Dae Yeong Kim, Hyemi Yun, Dayoung Kim, Woo Young Kim, Sanghee Kang, Sun Il Lee, Sang Cheul Oh. Cannabidiol enhances efficacy of atezolizumab via upregulation of PD-L1 expression by cGAS-STING pathway in triple negative breast cancer 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 5548.
Abstract 5561: Whole slide Imaging Mass Cytometry allows the rapid profiling of the immune landscape of histopathologically aggressive prostate tumors
Authors: Gorman Jennifer L. , Liu Lydia Y. , Hartig Jordan P. , Parsotam Nikesh , Khoo Amanda , Ignatchenko Vladimir , Asbury Sarah , Afiuni Somi , Gonzalez Ricardo , Geuenich Michael J. , Harrigan Caitlin F. , Lee Yuju , Chen Jianan , Lim Liang , Raza Qanber , Angel Peggi M. , Campbell Kieran , Liu Stanley K. , Downes Michelle R. , Drake Richard R. , Kislinger Thomas , King David , Jackson Hartland W.
Published: March 2024

Patients with Gleason pattern 4 or 5 prostate tumors have a high risk of biochemical recurrence and worse survival. Affected by their local environment, dynamic immune cell phenotypes can both hinder or drive cancer progression. To understand the proteomic environments that facilitate specific immune cell responses and interactions in advanced prostate cancer, we have spatially resolved the immune cell content and metabolic features of Gleason pattern 4 and 5 and subpatterns of prostate tumors. To scale quantitative multiplexed histopathology measurements to human disease, we have applied a new high-throughput whole slide modality of high-plex Imaging Mass CytometryTM to simultaneously quantify immune cells, metabolic states, prostate specific pathways, and biomarkers in 125 whole slide sections from 42 patients over 100 cm2 of tissue. It is essential to image whole slide sections in order to fully evaluate the complete heterogeneity of these cancer samples. In parallel, multi-region macrodissection shotgun proteomics and both glycan and extracellular matrix MALDI imaging mass spectrometry have quantified the proteome associated with specific immune cell environments. Together, we identify localized proteomic microenvironments associated with specific tumor supportive or inhibitory immune cell content in human tumors that may help differentiate which high-risk patients will have a rapid biochemical recurrence following radical prostatectomy.

Citation Format: Jennifer L. Gorman, Lydia Y. Liu, Jordan P. Hartig, Nikesh Parsotam, Amanda Khoo, Vladimir Ignatchenko, Sarah Asbury, Somi Afiuni, Ricardo Gonzalez, Michael J. Geuenich, Caitlin F. Harrigan, Yuju Lee, Jianan Chen, Liang Lim, Qanber Raza, Peggi M. Angel, Kieran Campbell, Stanley K. Liu, Michelle R. Downes, Richard R. Drake, Thomas Kislinger, David King, Hartland W. Jackson. Whole slide Imaging Mass Cytometry allows the rapid profiling of the immune landscape of histopathologically aggressive prostate tumors [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 5561.
Abstract 5566: Streamlining tissue sample preparation: A comparative study on the efficiency and reproducibility of the Omni-Stainer™ dewaxing and HIER protocol
Authors: Samusik Nikolay , Goltsev Yury , Kedei Noemi
Published: March 2024

The evolution of life sciences research has entailed a shift toward understanding cellular functions within tissue microenvironments, with an emphasis on cell- and tissue-specific relationships. A key challenge in these endeavors is the need for accurate data acquisition, which can be impeded by variability in the multistep manual assay preparations. In the quest for developing reliable and efficient tissue sample preparation workflows, two protocols using multiple dewaxing agents have been compared: the Omni-Stainer™ Dewaxing and HIER antigen retrieval protocol from Parhelia Biosciences, Inc. and the analogous one on Leica BOND Rx. The objective of this research was to assess the efficiency and reproducibility of these methods in the context of a four-color morphology immunostaining used for GeoMx DSP RNA and protein detection assays (Nanostring). We examined the efficiency of automated dewaxing using various non-toxic xylene alternatives, including C12-15 alkyl Benzoate, diethylene glycol, methyl octanoate or methyl decanoate, and compared them to the proprietary Leica Bond Dewaxing solution. Then, we compared the quality of post-HIER immunostaining using two different four-antibody panels on human jejunum samples. After several rounds of optimization, we found that the V4 of the open-source Omni-Stainer™ dewax-HIER protocol resulted in identical quality of morphology immunostaining compared to proprietary Leica Bond protocol. This study validates the Omni-Stainer™ Dewaxing and HIER protocol as a viable and efficient approach for automation of sample prep for GeoMx DSP studies.

Citation Format: Nikolay Samusik, Yury Goltsev, Noemi Kedei. Streamlining tissue sample preparation: A comparative study on the efficiency and reproducibility of the Omni-Stainer™ dewaxing and HIER protocol [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 5566.
Abstract 5586: Hijacking mutant E3 ligase for targeted protein degradation: Discovery of cancer-specific PROTACs for the treatment of FBXW7 R465C driven cancers
Authors: Zhang Hailong
Published: March 2024

Many cancers carry LOF mutations of tumor suppressor genes and drug discovery against these cancers are challenging. Fbxw7 is a major tumor suppressor E3 ligase and is frequently mutated (LOF) in cancer. Fbxw7 R465C mutation correlates with worse survival and resistance to both chemo- and targeted therapies. Blueray have discovered Fbxw7 R465C-selective ligands and developed PROTAC molecules selectively targeting cancers carrying Fbxw7 R465C mutation. The Fbxw7 R465C-based PROTACs show superior degradation activity for several target proteins and inhibit proliferation of cancer cells carrying Fbxw7 R465C mutations. These PROTACs show tumor growth inhibition in Fbxw7 R465C mutant cell derived xenograft models with clear PK/PD correlations. Development of bi-functional molecules such as PROTACs bring new options to target cancers with LOF mutations.

Citation Format: Hailong Zhang. Hijacking mutant E3 ligase for targeted protein degradation: Discovery of cancer-specific PROTACs for the treatment of FBXW7 R465C driven cancers [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 5586.