bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4323: Deletion of the lipid kinase PIKfyve in Kras-driven pancreatic genetically engineered mouse model
Authors: Yee Sarah N. , Jiang Xia , Cheng Caleb , Korkaya Ahmet , Mannan Rahul , Mehra Rohit , Qiao Yuanyuan , Chinnaiyan Arul M.
Published: March 2024

Background: Pancreatic ductal adenocarcinoma (PDAC) accounts for 95% of all pancreatic cancers and, as one of the most lethal cancers, has a five-year survival rate of approximately 6%. Autophagic processes have been reportedly elevated in PDAC; thus, the inhibition of autophagy leads to decreased tumor growth. Autophagic processes are catabolic mechanisms that recycle cellular components. Cells in stressful conditions, such as starvation, have elevated autophagy to redistribute energy to sustain cell survival; however, this can also lead to cell death when attempts to maintain cell viability fail. In addition, autophagy is known to promote immune evasion by tumors and cancer progression and appears to be required for the optimal development of PDAC. The lipid kinase PIKfyve converts phosphatidylinositol-3-phosphate to phosphatidylinositol 3,5-bisphosphate and is required in the late stage of the autophagic pathway. Blocking PIKfyve disrupts autophagic processes. However, the role of PIKfyve in PDAC development has not been fully understood. We investigated the role of PIKfyve in the progression of PDAC using a genetically engineered mouse model. Given the poor clinical outcomes of pharmacological inhibition of autophagy by chloroquine, we have evaluated the PIKfyve inhibitor ESK981 in the context of PDAC progression.

Methods: The pancreatic-specific deletion of PIKfyve was established on a Kras G12D, Tp53 R172H, and p48 Cre (KPC) or Kras G12D and p48 Cre (KC) background. The ratio of pancreatic mass to body weight was monitored at various time points. Histopathology evaluations were conducted based on hematoxylin and eosin staining and immunohistochemistry of cytokeratin 19 staining. Pharmacological inhibition of PIKfyve was performed on KPC mice using ESK981 monotherapy. Four weeks after vehicle or ESK981 treatment, pancreatic tissues were collected intact and weighed. Histopathology evaluations were performed to evaluate the lesion.

Conclusion: We demonstrated that the deletion of PIKfyve in pancreatic tissue significantly reduces the pancreatic mass weight compared to the PIKfyve wildtype counterpart and is coupled with less pancreatic intraepithelial neoplasia (PanIN) and PDAC development in KPC and KC mice. Compared to the vehicle treatment, pharmacological inhibition of PIKfyve by ESK981 on KPC mice resulted in a significant increase in the percentage of normal pancreatic tissue and reduced pancreatic lesion development.

Citation Format: Sarah N. Yee, Xia Jiang, Caleb Cheng, Ahmet Korkaya, Rahul Mannan, Rohit Mehra, Yuanyuan Qiao, Arul M. Chinnaiyan. Deletion of the lipid kinase PIKfyve in Kras-driven pancreatic genetically engineered mouse 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 4323.
Abstract 4331: Machine learning-based classification of tissue origin of cancer using methylation profiles
Authors: De Velasco Marco A. , Sskai Kazuko , Mitani Seiichiro , Kura Yurie , Minamoto Shuji , Haeno Takahiro , Hayashi Hidetoshi , Nishio Kazuto
Published: March 2024

Cancer of unknown primary (CUP) is a malignancy with poor prognosis and an unknown primary site and histologically unknown metastasis. Most patients receive empiric chemotherapy including platinum-taxane therapies but experience short survival times. Patients with poor prognosis CUP could benefit from optimizing drug therapy based on primary organ estimation. We constructed and evaluated an ensemble learning model to accurately determine the primary organ using methylation profiles of tumor tissues. Methylation data from 890 samples representing 10 types of cancer from TCGA were analyzed. After data preprocessing, we extracted the top 10,000 CpGs sites based on ANOVA and Gain Ratio or 100 CpG sites from a Gradient Boosting classifier. Performance was evaluated using several machine learning models. Unsupervised analysis was carried out to determine the relationships between the CpG sites selected by Gradient Boosting. Methylation profiling by ANOVA and Gain Ratio yielded favorable performance when using various machine learning models. Using gradient boosting as a feature selector reduced the number of CpG sites by 100-fold without compromising model performance. The training and validation sets showed favorable results for the classification of primary organs with ensemble models. In validation, classification accuracy was 91.2%, 93.5%, 89.7%, and 87.7% for Extreme Gradient Boosting, CatBoost, Random Forest, and Gradient Boosting, respectively. Further profiling of the selected methylation regions was correlated with cancer types and even revealed subgroups within breast and lung cancers. Gradient Boosting as a feature selector for DNA methylation profiling was highly effective in accurately determining tissue origin. Our study has outlined an approach whereby we used an embedded machine learning algorithm to identify a select set of informative features from complex high-dimension data to train and predict cancer type.

Citation Format: Marco A. De Velasco, Kazuko Sskai, Seiichiro Mitani, Yurie Kura, Shuji Minamoto, Takahiro Haeno, Hidetoshi Hayashi, Kazuto Nishio. Machine learning-based classification of tissue origin of cancer using methylation profiles [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 4331.
Abstract 4364: Molecular insight of non-canonical Gsk3β-Gli-AR axis: Therapeutic implications of truncated-Gli3 in castration-resistant prostate cancer
Authors: Kaushal Jyoti Bala , Raut Pratima , Seshacharyulu Sarathy , Alsafwani Zahraa W. , Sharma Gunjan , Khan Abdullah M. , Halder Sushanta , Rachagani Satyanarayana , Batra Surinder K. , Siddiqui Jawed A.
Published: March 2024

The aberrant activation of the hedgehog (Hh) signaling pathway causes the progression of therapy-resistant castration-resistant prostate cancer (CRPC). In this study, we aimed to unravel the biological significance of Gli-family proteins and their functional involvement of Gsk3β-mediated regulatory mechanism(s) in CRPC. We have discovered a novel function of the truncated form of Gli (t-Gli3) in advancing CRPC. This was accomplished through in silico analysis, in vitro experiments, PCa patient clinical data, and in vivo PCa MYC overexpression mouse models. Our investigation into the Gli3 regulation, typically influenced by receptor-mediated ciliary localization, uncovered a Smo-independent mechanism. Surprisingly, despite the lack of a transactivation domain in t-Gli3, we found a specific requirement for an androgen receptor variant 7 (AR-V7) for its action, as evidenced by co-immunoprecipitation and chromatin immunoprecipitation assays. Mechanistically, Gsk3β activation leads to the t-Gli3 generation, and inhibition of Gsk3β supported the accumulation of full-length Gli3 through a non-canonical mechanism. Knockdown of Gsk3β (Gsk3β KD) reduces CRPC cell proliferation in 2-D and 3-D culture models, inhibiting key proliferative signaling pathways and inducing apoptosis via mitochondrial fragmentation. These findings were supported using an orthotropic PCa mouse model. RNA-seq analysis also showed upregulated phenotype enrichment of the apoptosis, P53, and glycolysis pathway genes in 22Rv1Gsk3β KD cells. Compared to scramble, a lower OCR/mitochondrial respiratory rate is evident in 22Rv1Gsk3β KD cells. Next, our exploration of potential therapies for PCa showed that individually targeting Smo or Gli1 is insufficient to inhibit cell viability. Interestingly, we uncovered that solely targeting Gli3 was sufficient to inhibit the growth of CRPC cells. In conclusion, our study provides the significance of Gli-family proteins and novel insights into the interplay of Gsk3β, t-Gli3, and AR, offering therapeutic implications in CRPC.

Citation Format: Jyoti Bala Kaushal, Pratima Raut, Sarathy Seshacharyulu, Zahraa W. Alsafwani, Gunjan Sharma, Abdullah M. Khan, Sushanta Halder, Satyanarayana Rachagani, Surinder K. Batra, Jawed A. Siddiqui. Molecular insight of non-canonical Gsk3β-Gli-AR axis: Therapeutic implications of truncated-Gli3 in castration-resistant 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 4364.
Abstract 4372: Epithelial-to-mesenchymal transition-driven secretory program underlies vulnerabilities in lung cancer
Authors: Fulp Kevin L. , Obaleye Oluwafunminiyi E. , Xiao Guan-Yu
Published: March 2024

Epithelial-to-mesenchymal transition (EMT) is a driving force behind lung adenocarcinoma (LUAD) progression. Although substantial evidence has been attained in the involvement of EMT and its regulatory mechanisms in cancer, few effective EMT-targeted therapies have been available in the clinic thus far. It is urgent to develop new therapeutic strategies for improving patient outcomes. We have identified RAB6A as a master regulator of EMT-driven secretory trafficking, which coordinates cancer cell invasion and immunosuppression in LUAD. We found that RAB6A expression was associated with a poor prognosis in LUAD patients and that RAB6A inhibition in our LUAD models reversed resistance to immune checkpoint inhibition with PD-L1 blockade, an emerging clinical problem. Thus, RAB6A machinery is a therapeutic target of interest in EMT-driven cancers. Screening approaches to identify selective RAB inhibitors are in their infancy, a challenge that can be overcome only by obtaining insights into the regulation of RAB6A. RAB6A is a small GTPase whose activity is controlled by guanine nucleotide exchange factors (GEFs) like RIC1 and RGP1, and GTPase activating proteins (GAPs) like RABGAP1, as well as other effector proteins. While these GEFs, GAPs, and effectors are all known regulators of RAB6A function and are frequently amplified in different cancer types, their specific functions in cancer progression are still unknown. To establish the causal relationship between these proteins and EMT-driven LUAD progression, we utilize human and murine LUAD cell lines that have been characterized with respect to EMT status. Our findings here show that the intervention of RAB6A activity via depletion of these regulators impairs the recruitment of RAB6A to the Golgi. We demonstrate that knocking down the GEFs, RIC1 and RGP1, significantly decreases invasion while having negligible effects on the migrative and proliferative abilities of these cells. RABGAP1 depletion, on the other hand, reduces cell proliferation but has no effects on the migration and invasion of the cells. Consistent with these results, inactivation of RAB6A abolishes the EMT-dependent pro-metastatic secretion. Mechanistically, the EMT activator, ZEB1, upregulates RGP1 via silencing miR-148a that targets this GEF to activate RAB6A. These findings elucidate the regulatory mechanisms underlying the EMT-driven secretory program, providing a foundation for therapeutic intervention to prevent the progression of LUAD.

Citation Format: Kevin L. Fulp, Oluwafunminiyi E. Obaleye, Guan-Yu Xiao. Epithelial-to-mesenchymal transition-driven secretory program underlies vulnerabilities in 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 4372.
Abstract 4377: AT rich interaction domain 5a promotes gastrointestinal tumorigenesis by regulating YAP and STAT3 pathways
Authors: Taniguchi Koji , Hamada Kazuya , Tanaka Shugo , Kurosu Hiroyuki , Kawakita Issei , Kumagai Kentaro , Nakazono Kentaro , Iwasaki Sari , Tanaka Satoshi
Published: March 2024

Background: Chronic inflammation and an inflammatory cytokine, interleukin(IL)-6, play important roles in gastrointestinal tumorigenesis and metastasis. Recently, autocrine IL-6 has been reported to promote cancer development and progression in gastrointestinal cancer. However, it is still unknown how IL-6 level is regulated in gastrointestinal cancer cells. RNA-binding proteins (RBPs) are known to be one of the regulatory mechanisms of cytokine production, including IL-6, especially in immune cells. AT rich interaction domain 5a (Arid5a), one of the RBPs, has been reported to bind to IL6 3’UTR and regulates its stability and expression. Therefore, we aimed to elucidate the role of Arid5a in gastrointestinal cancer, especially gastric and colon cancer.

Methods: Human gastric and colon cancer cell lines were used in this study. Arid5a knocked-down gastric and colon cancer cells were generated with lentiviral transduction of shRNAs targeting Arid5a and their phenotypes were investigated by several assays including MTT, apoptosis and sphere formation assays. Bulk RNA-seq analysis was performed using Arid5a knocked-down gastric and colon cancer cells.

Results: In both human gastric and colon cancer cell lines, Arid5a knockdown suppressed cancer cell proliferation and spheroid formation, and increased apoptosis. Unexpectedly, IL6 mRNA expression was not correlated with Arid5a expression level. We found that Arid5a knockdown suppresses the activation of YAP and STAT3 by western blot analysis. We identified several new Arid5a target genes by bulk RNA-seq analysis.

Conclusion: Arid5a plays an important role in the regulation of cancer cell proliferation, apoptosis and stemness in human gastric and colon cancer cells, perhaps independently of IL-6. Arid5a regulates YAP and STAT3 pathways by unknown mechanisms. We are now investigating how Arid5a regulates YAP and STAT3 pathways by focusing new Arid5a target genes.

Citation Format: Koji Taniguchi, Kazuya Hamada, Shugo Tanaka, Hiroyuki Kurosu, Issei Kawakita, Kentaro Kumagai, Kentaro Nakazono, Sari Iwasaki, Satoshi Tanaka. AT rich interaction domain 5a promotes gastrointestinal tumorigenesis by regulating YAP and STAT3 pathways [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 4377.
Abstract 4379: RING1, a novel E3 ubiquitin ligase for CIP2A, negatively regulates smoking-induced lung tumorigenesis
Authors: Jeong In-ho , Lee Chang-Whan Peter , Lim Hwan Jung , Park Seong Jun , Hyun Ji Young
Published: March 2024

Lung cancer is the second incidence rate of all new cancer diagnoses and the leading cause of cancer-related deaths globally. To develop novel diagnostic and therapeutic targets for lung cancer, there are emerging needs for molecular biological research on the occurrence and progression. Among the targets, CIP2A has been studied for promoting various cancer types, but detailed underlying mechanisms are needed to be further investigated. In this study, it was verified that CIP2A is overexpressed in lung cancer tissues, particularly amongst those with a smoking history, compared to adjacent normal tissues. CIP2A knockdown in lung cancer cells efficiently reduced cell proliferation and migration capacity. Through the mass spectrometry analysis on A549 cells overexpressing CIP2A, RING1 was identified as a candidate for E3 ligase of CIP2A. The interaction of the two proteins and ubiquitin chain regulation by RING1 was verified by immunoprecipitation. RING1 knockdown enhanced proliferation and migration of lung cancer cells, and these effects result from the upregulation of CIP2A and its downstream molecules, c-Myc and cyclin B1. To further study a trigger for RING1 expression changes in lung tumorigenesis, cigarette smoke extract (CSE) was applied for the following experiments. CSE treatment depleted RING1 mRNA, including protein expression. Decreased RING1 level led to upregulation of CIP2A and c-MYC. Collectively, these results reveal novel roles of the RING1 and CIP2A in lung cancer progression caused by smoking and propose a potential biomarker candidate for the therapeutic and diagnostic targets.

Citation Format: In-ho Jeong, Chang-Whan Peter Lee, Hwan Jung Lim, Seong Jun Park, Ji Young Hyun. RING1, a novel E3 ubiquitin ligase for CIP2A, negatively regulates smoking-induced lung tumorigenesis [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 4379.
Abstract 439: Tackling oxidative phosphorylation of glioblastoma stem cells through the specific impairment of transmembrane chloride intracellular channel 1
Authors: Cianci Francesca , Verduci Ivan , Cazzoli Riccardo , Minucci Saverio , Mazzanti Michele
Published: March 2024

Solid cancer cells show higher energy and biomolecules requirements compared with healthy cells, making the targeting of cancer metabolic dysfunctions an appealing therapeutic approach. Tackling the tumor metabolism is a daunting task, due to the ability of cancer cells to re-organize their metabolism switching between glycolysis and oxidative phosphorylation. Cancer metabolic plasticity and re-programming is partially supported by altered ionic channels expression and activity. Our laboratory has described the chronic presence transmembrane form of Chloride Intracellular Channel 1 (tmCLIC1) as a marker of malignancy in tumor cells and a possible therapeutic target since it is mainly absent in healthy cells. CLIC1 is described as a metamorphic protein able to shuttle between the cytoplasmic form to a transmembrane conformation. In the present investigation, we show that tmCLIC1 acts as a privileged metformin target in glioblastoma stem-like cells. Metformin is the first-line drug for type 2 diabetes and has been proposed as an antineoplastic drug, but no direct evidence of its’ membrane permeability nor of a specific membrane receptor in cancer cells has been found yet. Here we demonstrate that metformin impairs tmCLIC1 activity by direct and specific binding coordinated by arginine 29. This residue mutation prevents metformin from tmCLIC1 binding and abolishes the drug's effect on glioblastoma cells in 2D and 3D models and its actions on mitochondrial respiration. In vivo experiments in zebrafish embryos and mice orthotopically engrafted with glioblastoma cells and treated with metformin have shown that metformin binding to tmCLIC1 is crucial for its anti-neoplastic effect.

Citation Format: Francesca Cianci, Ivan Verduci, Riccardo Cazzoli, Saverio Minucci, Michele Mazzanti. Tackling oxidative phosphorylation of glioblastoma stem cells through the specific impairment of transmembrane chloride intracellular channel 1 [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 439.
Abstract 4399: HMGA1 is an epigenetic regulator and plays a critical role in melanoma recurrence
Authors: Mou Haiwei , DeRosa Kristen , Yakovishina Veronika , Chen Yeqing , Reynolds Abdiel Mandella , Xiao Min , Thomas Monzy , Herlyn Meenhard
Published: March 2024

Among various genetic mutation in melanoma, BRAFV600E is one of the key drivers of melanoma initiation and progression and has become the frontline target in clinical trials. Although BRAF/MEK inhibitors show very promising therapeutic outcomes, recurrence or relapse is still a major challenge and its underlying mechanisms are still poorly understood. We hypothesized that survival of recurrent tumors is BRAF independent and relies on epigenetic reprogramming. To test our hypothesis, we used either pharmacological inhibition of BRAF/MEK or CRISPR/Cas9 mediated knockout of BRAF to create cell/tumor models of BRAF-independent survival. Cut&Run sequencing was then used to identify epigenetic alterations regulated by H3K4me3 or H3K27Ac in a genome scale and capture the landscape of epigenetic alterations of BRAF-independent cell survival. Combining regular bulk RNAseq, we narrowed down our top candidates and focused on one of the functionally validated candidates, HMGA1. Interestingly, CRISPR/Cas9 mediated HMGA1 knockout cells show significantly slower growth in both in vitro colony formation assays and in vivo xenografts assay in BRAF/MEK resistant Patient-Derived-Xenograft (PDX) tumor models resembling melanoma recurrence. Furthermore, we selected CRISPR/Cas9 single knockout cells of HMGA1, which is a pure genetic depletion model, and confirmed the phenotype of impaired tumor growth of HMGA1 knockout cells. We then performed RNAseq and ChIPseq, and identified downstream targets of HMGA1 and elucidated mechanisms by which HMGA1 reprograms epigenetics of recurrence. Utilizing the single knockout cell, we re-introduced HMGA1 in the pure knockout cells, and anticipated that restoration of HMGA1 in pure HMGA1 knockout cells rescues impaired tumor growth and confer cells resistance to BRAF/MEK inhibition. Finally, we subcutaneously injected the HMGA1 single knockout cells into humanized mice and tested whether epigenetic alterations perturb the immune microenvironment and sensitize cells to immunotherapy. In conclusion, this study sheds new lights on how melanoma cells reprogram the epigenome to develop mechanisms of recurrence. Identification of HMGA1 and its upstream or downstream targets provides potential druggable targets of overcoming relapse after BRAF/MEK inhibitor therapy.

Citation Format: Haiwei Mou, Kristen DeRosa, Veronika Yakovishina, Yeqing Chen, Abdiel Mandella Reynolds, Min Xiao, Monzy Thomas, Meenhard Herlyn. HMGA1 is an epigenetic regulator and plays a critical role in melanoma recurrence [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 4399.
Abstract 4401: GATA6 is a novel regulator of gene expression and 3D genome in colorectal cancer
Authors: Lyu Huijue , Chen Xintong , Cheng Yang , Zhang Te , Wang Ping , Wong Josiah Hiu-yuen , Wang Juan , Stasiak Lena , Sun Leyu , Yang Guangyu , Wang Lu , Yue Feng
Published: March 2024

Colorectal cancer (CRC) is one of the most lethal and prevalent malignancies with elusive molecular causes. While the abnormal activity of transcription factors has been reported as a vital component of cancer progression, the mechanism through which they function remains unclear. Here, through the analysis of primary human CRC tissue data, we identified GATA6 as a CRC specific regulator, whose expression upregulation is potentially associated with promoter hypomethylation. In the human genome, GATA6 showed preferential binding at tumor specific active enhancers. Through both auxin-inducible degron (AID) and CRISPR knockout, we showed that GATA6 depletion severely impaired clonogenicity and proliferation. GATA6 depletion caused the loss of CRC specific open chromatin, suggesting a specific regulatory role of GATA6 in CRC pathogenesis. Interestingly, we also discovered the co-occupancy of GATA6 with CTCF and its direct involvement in promoter enhancer loops, suggesting the possibility that GATA6 mediate transcriptional regulation through 3D genome. The loss of GATA6 led to alterations in E-P chromatin interactions of a panel of oncogenes, accompanied by the oncogene downregulation. Finally, we showed that GATA6 loss is detrimental to the xenograft tumor growth and thereby rescued mice survival. Taken together, we unrevealed a novel mechanism by which GATA6 contributes to CRC.

Citation Format: Huijue Lyu, Xintong Chen, Yang Cheng, Te Zhang, Ping Wang, Josiah Hiu-yuen Wong, Juan Wang, Lena Stasiak, Leyu Sun, Guangyu Yang, Lu Wang, Feng Yue. GATA6 is a novel regulator of gene expression and 3D genome in colorectal 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 4401.
Abstract 4427: Do changes in lipid metabolism link obesity to pancreatic cancer
Authors: Ghosh Rita , Ajit Deepa , Woodworth Jillian , Fritze Danielle , Cigarroa Francisco G. , Halff Glenn A. , Kumar Addanki Pratap
Published: March 2024

The near equal incidence and mortality rates of pancreatic cancer, combined with projections that pancreatic cancer will become the second-most common cancer-related deaths by 2050, underscore the need to identify patients with early disease and interrupt this trajectory. Obesity, weight gain and waistline have been implicated in increasing the risk of pancreatic cancer. Although metabolomic analyses of pancreatic cancer patients have established correlations between phospholipids, lysophospholipids with treatment outcomes, the association between metabolites, obesity, and pancreatic cancer remains largely understudied. The objective of this pilot study was to determine differences in serum metabolites in obese and overweight pancreatic cancer patients compared with healthy non-obese subjects. Our long-term goal is to develop serum marker(s) that may be used to prevent advanced pancreatic cancer and thus improve outcomes for these patients. Serum was obtained from healthy subjects (n=11; BMI range from 18-25), overweight (n=9; 25-30) and obese (n=7; >30) pancreatic cancer patients from an IRB approved study. Males (n=12) and females (n=15) were represented in the study. Global metabolic profiles were determined using Ultrahigh performance liquid chromatography-tandem mass spectroscopy. Raw data was extracted, peaks were identified and processed at Metabolon using the Laboratory Information Management System. Comparison between overweight pancreatic cancer patients and healthy controls identified 403 biochemicals (111 upregulated and 292 downregulated; p <0.05) and 93 biochemicals (40 upregulated and 53 downregulated; 0.05<p<0.10). Comparison of the differences in biochemicals between obese pancreatic cancer patients and healthy controls showed changes in 293 biochemicals (71 upregulated and 222 downregulated; p <0.05) and 123 biochemical changes at 0.05<p<0.10 (42 increased and 81 decreased). 38 (p <0.05) and 47 (0.05<p<0.10) differential levels of biochemicals were identified when obese and overweight pancreatic cancer patients were compared. Random forest analysis showed that the 30 top ranking biochemicals were involved in lipid metabolism, amino acid metabolism, nucleotide metabolism, peptide, xenobiotics, and carbohydrate metabolism. These data suggest an association between changes in lipid metabolism may be another link between obesity and pancreatic cancer. This project was funded in part by VA-Merit Award (I01 BX003876).

Citation Format: Rita Ghosh, Deepa Ajit, Jillian Woodworth, Danielle Fritze, Francisco G. Cigarroa, Glenn A. Halff, Addanki Pratap Kumar. Do changes in lipid metabolism link obesity to pancreatic 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 4427.
Abstract 4439: Decoding the metabolic symphony TP53 mutation-driven rewiring of cellular metabolism in non-small cell lung carcinoma
Authors: Khan Jiyauddin , Rehman Asad Ur , Mathur Ankit , Bhatrajuc Naveen Kumar , Tulid Anannya , Rajput Divya , Iqbal Mohammad Askandar , Saluja Daman
Published: March 2024

TP53 is a critical regulator of major metabolic pathways. Metabolic reprogramming is one of the "hallmarks of cancer" and drives tumorigenesis. Frequent p53mutations not only eradicate tumour suppressor capacities but also confer various activities that impact the alteration of metabolic pathways now regarded as central for tumour development and progression. We selected three hotspot mutants (R175H, R273H and R249S) and wtp53 to evaluate the effects in the human non-small cell lung carcinoma cell line (NCI-H1299). Differential expressions of p53 mutants were observed in normal and glucose/glutamine starvation. However, WTp53 expression was not found to be affected. Under both the glucose and glutamine starvation, inhibition of the cell growth and migratory potential of mutant cells was observed which was more prominent in glutamine starvation. Basal respiration and ATP production in p53-/- R273H and R249S significantly increased under glucose starvation. However, Non-mitochondrial oxygen consumption and maximal respiration were found to be decreased in all the cell lines. Importantly, the cells harbouring mutation R175H increase the glycolysis and TCA cycle. The metabolic intermediates of the urea cycle were found to be increased by nearly fourfold in R273H cells. Indicating increased utilization of the urea cycle instead of the TCA cycle, which has been known to be fueled by glutamine for anaplerosis. This study demonstrates that mutp53 influences several metabolic processes and has an influence on cancer cell aggression under starvation of main carbon sources (Glucose and Glutamine). In starved conditions, cells with p53 mutations enhance mitochondrial activity and use alternative pathways in non-small cell lung cancer cells. This might provide a foundation for the development of more effective targeted therapeutics/pharmacological approaches toward variants of mutant p53.

Citation Format: Jiyauddin Khan, Asad Ur Rehman, Ankit Mathur, Naveen Kumar Bhatrajuc, Anannya Tulid, Divya Rajput, Mohammad Askandar Iqbal, Daman Saluja. Decoding the metabolic symphony TP53 mutation-driven rewiring of cellular metabolism in non-small cell lung 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 4439.
Abstract 4454: Manipulation of the amino acid metabolism promotes therapeutic efficacy through targeting lysosome in glioblastoma
Authors: Jing Yongwei , Kobayashi Masahiko , Hirao Atsushi
Published: March 2024

Nutrients are converted by the body to smaller molecules, which are utilized for both anabolic and catabolic reactions. Cooperative regulation of these metabolic processes is critical for maintaining tissue homeostasis. Based on these findings, our group has been focusing on how the regulation of nutrient-driven metabolism controls the malignancy of cancer cells. Metabolic regulation has been considered crucial for cellular adaptation to environmental changes and promoting survival and proliferation. Recent studies showed the successful applications of targeting specific nutrients for cancer therapy. In this study, we developed a new lysosome-targeting therapeutic strategy, centered around the manipulation of the amino acid metabolism for GBM. Using patient-derived GBM cells, we found that lysosomal proteolytic activity is a unique metabolic biomarker representing malignant phenotypes of GBM and that it is closely correlated with the efficacy of current conventional therapy for GBM patients. Furthermore, the MiT/TFE family members, TFEB and TFE3, which are the master regulators of lysosomal biogenesis, controlled malignant progression and therapeutic efficacy in vitro and vivo. Combinatory analyses with clinical patient samples and xenograft models demonstrated that the MiT/TFE family plays a crucial role as a regulator of malignant properties in GBM. Analysis of The Cancer Genome Atlas (TCGA) glioma dataset, which includes data from patients with Grade 2, 3, and 4 (GBM) gliomas, showed that higher expression of the MiT/TFE family was significantly associated with shorter survival. Interestingly, we discovered that an essential amino acid controls lysosomal biogenesis and membrane integrity by regulation of nitric oxide signaling pathway. Finally, we screened the potential anti-cancer drugs, including temozolomide, exhibiting the synergy effect in amino acid-restriction conditions by conducting a drug screening using a clinically available anti-cancer drug library. Our study demonstrated that lysosomal function, supported by amino acid metabolism, plays a critical role in the regulation of GBM malignant status and proposed precision nutrition as a promising therapeutic approach.

Citation Format: Yongwei Jing, Masahiko Kobayashi, Atsushi Hirao. Manipulation of the amino acid metabolism promotes therapeutic efficacy through targeting lysosome in glioblastoma [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 4454.
Abstract 4475: Discovery of an oral tricyclic STING agonist with superior pharmacokinetic properties and potent in vivo efficacy
Authors: Zhao Hong-Yi , Liu Zhongwei , Mao Shuai , He Miao , Wang Meilin , Wen Bo , Gao Wei , Sun Duxin
Published: March 2024

Stimulator of interferon genes (STING) plays a pivotal role in regulating immune microenvironment for cancer immunotherapy. However, the use of most STING agonists has been hindered by the necessity for intra-tumoral or intravenous administration, underscoring the challenge in developing an orally bioavailable STING agonist with favorable pharmacokinetic (PK) properties. In this study, we discovered oral STING agonists featuring a novel tricyclic benzo[4,5]thieno[2,3-c]pyrrole-1,3-dione scaffold, thus achieving both superior PK properties and potent in vivo efficacy. Our lead compound, ZSA-51, exhibited nanomolar cellular STING activation activity (EC50 = 100 nM) in THP1 cells, surpassing the reported oral STING agonist MSA-2 by 32-fold (EC50 = 3200 nM). Furthermore, ZSA-51 demonstrated superior PK properties with an oral bioavailability of 49%, and robust in vivo antitumor activity both in colon and pancreatic cancers model upon oral administration. Notably, ZSA-51 displayed preferential distribution to the lymph nodes and spleen, enhancing its systemic immune-stimulating effects. The specificity of ZSA-51 was further confirmed by a comparison with a negative control compound (ZSA-52NC2) that was unable to stimulate in vitro and in vivo STING activity. Molecular docking and MD simulation confirmed that the active form of ZSA-51 stably bound to STING dimer with validated hydrogen bond network. Taken together, our findings suggest ZSA-51 as a promising oral STING agonist characterized by superior PK properties and potent in vivo efficacy, holding potential for future development for cancer immunotherapy.

Citation Format: Hong-Yi Zhao, Zhongwei Liu, Shuai Mao, Miao He, Meilin Wang, Bo Wen, Wei Gao, Duxin Sun. Discovery of an oral tricyclic STING agonist with superior pharmacokinetic properties and potent in vivo efficacy [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 4475.
Abstract 4489: Developing dual FLT3/MNK inhibitors to overcome sorafenib resistance in FLT3-ITD AML cells
Authors: Zhao Linxiang , Zuo Shuwei , Xing Kun , Yue Xiaoshuang , Zhang Huimin , Zhang Jingyi , Waxman Samuel , Jing Yongkui
Published: March 2024

Acute myeloid leukemia (AML) patients with FLT3-ITD mutations are associated with poor prognosis. FLT3-ITD inhibitors developed only result in transient disease remission with disease relapse and resistance. Agents overcoming FLT3-ITD inhibitor resistance need to be developed. Sorafenib is one of FLT3-ITD inhibitors used in clinic. Using FLT3-ITD AML MOLM-13 cell line, we established a sorafenib resistant subclone MOLM-13/Sor, explored the resistance mechanism and revealed the overactivated mTOR signaling. MNK as one of the alternative mTOR signaling pathways is activated. MNK inhibitor eFT508 could overcome sorafenib resistance. Previously we developed a dual pyrido[3,2-d]pyrimidine MNK/PIM inhibitor 21o. Through optimization of 21o we obtained two new compounds H104 (IC50 values: MNK1 19 nM; MNK2 8 nM; FLT3-ITD 46 nM; PIM1 1388 nM) and H118 (IC50 values: MNK1 35 nM; MNK2 21 nM; FLT3-ITD 25 nM; PIM1 518 nM) with selective inhibition of MNK and FLT3 and losing PIM inhibition ability. H104 and H118 show better antiproliferative efficacy in FLT3-ITD MOLM-13 cells (GI50: 1.07±0.04 μM and 0.99±0.08 μM) than non-FLT3-ITD HL-60 cells (GI50: 7.04±0.15 μM and 4.78±0.31 μM). More intriguingly H104 and H118 exhibit superior antiproliferative effects in sorafenib resistant MOLM-13/Sor cells (GI50: 0.44±0.05 μM and 0.24±0.06 μM). H104 and H118 decreased the levels of p-eIF4E, c-myc and Mcl-1, the downstream substrates of FLT3-ITD and MNK. Our data indicate that the activated MNK is one mechanism of FLT3-ITD resistance and the dual MNK/FLT3 inhibitors have advantage for FLT3-ITD AML treatment.

Citation Format: Linxiang Zhao, Shuwei Zuo, Kun Xing, Xiaoshuang Yue, Huimin Zhang, Jingyi Zhang, Samuel Waxman, Yongkui Jing. Developing dual FLT3/MNK inhibitors to overcome sorafenib resistance in FLT3-ITD AML 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 4489.
Abstract 4512: Discovery of highly potent, selective, and orally bioavailable IKZF2 degrader and its anti-tumor activity in syngeneic mouse models
Authors: Park Seulki , Moon Jeong Hee , Lee Gaseul , Kim Hyun Jin , Kim Jeong-Hoon , Hwang Jong Yeon
Published: March 2024

Molecular glue degraders (MGDs) are emerging as innovative therapeutic modalities, owing to their efficacy in targeting previously undruggable targets. MGDs induce close proximity between the target protein and E3 ligase, resulting in the degradation of the target protein. In the wake of the remarkable success of PD-1/PD-L1 inhibitors, various approaches to modulate the activity of regulatory T cells (Tregs) activity have been explored. Tregs represent the primary immune suppressor and significantly impede antitumor immune responses. IKZF2, a marker of stable suppressive Treg, is essential for maintaining the stable Treg cell phenotype. Depletion of IKZF2 can induce a transition from Treg to effector T cell (Teff) phenotypes, thereby enhancing anti-tumor responses. Leveraging an Immunomodulatory drug (IMiD), Novartis has developed the IKZF2 degrader DKY709, which is currently undergoing Phase I clinical trials, both as a monotherapy and in combination with a PD-1 immune checkpoint inhibitor. In this presentation, we present the preclinical results of the best-in-class IKZF2 degrader, PRT-101. PRT-101 elicits rapid and robust degradation of IKZF2, demonstrating subnanomolar DC50 and achieving 100% Dmax in a proteasome- and CRBN-dependent manner. However, PRT-101 does not induce the degradation of well-known neosubstrates, including IKZF1, IKZF3, SALL4, and CK1a. Global proteomic analysis reveals that PRT-101 exclusively facilitates IKZF2 degradation. The degradation of IKZF2 by PRT-101results in an increase in IL-2 secretion, a marker of T effector function. Furthermore, oral administration of PRT-101 exhibits excellent pharmacokinetics, concurrent with IKZF2 degradation, yielding superior anti-tumor effects compared to DKY709 in the MC38 mouse syngeneic model. In conclusion, our findings underscore the potential of the novel IKZF2 degrader as a promising immuno-oncology target for the treatment of solid tumors.

Citation Format: Seulki Park, Jeong Hee Moon, Gaseul Lee, Hyun Jin Kim, Jeong-Hoon Kim, Jong Yeon Hwang. Discovery of highly potent, selective, and orally bioavailable IKZF2 degrader and its anti-tumor activity in syngeneic mouse models [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 4512.
Abstract 4515: Orally bioavailable PROTAC based MDM2 degrader
Authors: Aguilar Angelo , Yang Jiuling , Li Yangbing , McEachern Donna , Wang Shaomeng
Published: March 2024

Activation of the tumor suppressor p53, through inhibition of the MDM2 protein, has been pursued as a cancer therapeutic strategy and has produced many distinct inhibitors that are in clinical trials. A limitation arising from inhibiting the MDM2-p53 interaction is the upregulation of MDM2, itself a target gene of p53, and this attenuates the activation of p53 and efficacy of the inhibitors. To circumvent this limitation, we previously reported the first PROTAC based MDM2 degraders. These induced and sustained robust degradation of MDM2, achieved stronger p53 activation, and more potent anticancer activity than MDM2 inhibitors thus representing a new therapeutic strategy for targeting MDM2. Currently, all the PROTAC based MDM2 degraders are all dosed intravenously. Here we describe our design, synthesis, and optimizations that led to the discovery of the first orally bioavailable PROTAC based MDM2 degrader and our investigation of its therapeutic potential and mechanism of action. Consistent with its design to effectively degrade MDM2, our PROTAC effectively induces rapid degradation of MDM2 resulting in accumulation of wild-type p53 protein and activates p53 transcriptional activity in leukemia cells without accumulation of MDM2 protein. Consequently, it potently inhibits cell growth and induces apoptosis at low nano-molar concentrations in ALL and AML cell lines >10-100 times more potent than MDM2 inhibitors; and, after 50 mg/kg oral dose, 5 days/week for 3 weeks, it increased the median survival by 26 days of mice with disseminated RS4;11 cancer.

Citation Format: Angelo Aguilar, Jiuling Yang, Yangbing Li, Donna McEachern, Shaomeng Wang. Orally bioavailable PROTAC based MDM2 degrader [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 4515.
Abstract 4533: Identification of DAT-2000A, a novel potent PARG inhibitor that selectively inhibits PARPi-resistant and homologous-recombination-deficient tumors
Authors: Yan Dan , Zhang Yan , Yu Zhangqi , Zhang Yao , Zhang Jingxi , Wang Bin , Chen Huixian , Shi Jingxue , Bao Zhiwei , Lin Xiaoling , Zhuo Jincong , Zhou Kevin
Published: March 2024

A significant portion of patients with homologous recombination repair deficiencies(HRD) do not respond to PARP inhibitors, and even among those who initially respond, resistance often develops after PARP inhibitor treatment. This underscores the unmet clinical need to address the challenges in the treatment of HRD patients. Poly (ADP-ribose) glycohydrolase (PARG) plays a key role in hydrolyzing PAR chains from PARylated protein substrates, such as PARP1, serving as a critical checkpoint in DNA damage repair and the control of DNA replication stress. Therefore, PARG has emerged as a promising target for cancer therapy. Cancer cells experiencing replication stress, such as HRD breast cancer cells and those resistant to PARPi, exhibit sensitivity to PARG inhibition. DAT-2000A is a potent, selective, orally bioavailable small-molecule inhibitor of PARG, which directly binds to the catalytic domain of PARG, inducing the accumulation of poly-PAR chains at DNA lesions, and exhibits notable anti-proliferative activity across a wide range of HRD tumors both in vitro and in vivo. Biochemical assays confirm DAT-2000A's high potency and selectivity as an inhibitor of PAR-chain hydrolysis. In cellular assays, DAT-2000A demonstrates selective sensitivity in HRD cells, distinguishing itself from PARPi across various indications. Preclinical studies involving CDX and PDX xenograft models reveal that DAT-2000A exerts robust anti-tumor effects in both PARPi-sensitive and -resistant settings. Furthermore, it induces a dose and time-dependent accumulation of PAR chains, which may serve as a reliable pharmacodynamic biomarker indicative of PARG target engagement. In conclusion, DAT-2000A represents an innovative targeted therapy that warrants further investigation in clinical trials for the treatment of HRD cancers and beyond.

Citation Format: Dan Yan, Yan Zhang, Zhangqi Yu, Yao Zhang, Jingxi Zhang, Bin Wang, Huixian Chen, Jingxue Shi, Zhiwei Bao, Xiaoling Lin, Jincong Zhuo, Kevin Zhou. Identification of DAT-2000A, a novel potent PARG inhibitor that selectively inhibits PARPi-resistant and homologous-recombination-deficient 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 4533.
Abstract 4546: Pegargiminase and melphalan as a novel drug combination strategy for uveal melanoma
Authors: Pavlyk Iuliia , Carpentier Josephine , Szlosarek Emilia Appolonia , Chan Pui Ying , Bomalaski John S. , Szlosarek Peter Wojciech
Published: March 2024

Uveal melanoma (UM) is a hard-to-treat arginine auxotrophic cancer with approximately 50% of patients succumbing to metastases predominantly to the liver with a median overall survival of 19-22 months and a 5 year survival of around 10%. Novel drug strategies are urgently needed beyond the currently available immunotherapies that provide durable disease control in a small subset of patients. Arginine deprivation with pegylated arginine deiminase (ADI-PEG20; pegargiminase) is a novel anti-metabolite therapy which demonstrated activity in early phase trials in patients with UM, and more recently, increased survival in patients with the aggressive arginine-dependent cancer, non-epithelioid mesothelioma in the global phase 3 trial, ATOMIC-Meso. Here, we investigated the preclinical rationale for combining pegargiminase with melphalan, a drug which is delivered directly to the liver using an FDA-approved device from Delcath for patients with hepatic-centric UM disease. Two of four uveal melanoma cell lines were negative for expression of the rate-limiting enzyme for arginine production, argininosuccinate synthetase 1 (ASS1) and were submitted for drug evaluation accordingly. ADI-PEG20 treatment of ASS1-deficient cell lines 91.2 and MP41 demonstrated sensitivity to ADI-PEG20 (500ng/ml) compared to MP38 and MP46 ASS1-proficient cell lines. Moreover, the combination of ADI-PEG20 and melphalan (0.77µM) had at least an additive effect on ASS1 negative cell lines in 2D assay (92.1 p-value 0.0061; MP41 p-value is 0.0053). UM cell line proliferation was decreased by 50% in the combination group compared to ADI-PEG20 alone by 6 days of culture. Experiments to assess cytotoxicity and cell death analysis are ongoing. This drug combination therapy has the potential to improve outcomes in patients with uveal melanoma. Based on the good tolerability and safety of both drugs in patients, a clinical trial of pegargiminase with melphalan is planned for 2024 (ATOMIC-UM).

Citation Format: Iuliia Pavlyk, Josephine Carpentier, Emilia Appolonia Szlosarek, Pui Ying Chan, John S. Bomalaski, Peter Wojciech Szlosarek. Pegargiminase and melphalan as a novel drug combination strategy for uveal melanoma [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 4546.