bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 4297: Interrogating metabolic heterogeneity and cooperation in lung cancer collective cell invasion
Authors: Robinson Isaac E. , Matsuk Veronika , Shanmugam Mala , Mouw Janna K. , Marcus Adam I. 
Published: March 2024

Abstract
Tumor heterogeneity contributes to tumor progression and a variable response to treatment. We have previously shown that tumor heterogeneity - including metabolic, transcriptional and mutational - underlies non-small cell lung cancer (NSCLC) collective invasion. Using stable subpopulations derived with our Spatiotemporal Cellular and Genomic Analysis (SaGA) technique, we found that two distinct subpopulations of the H1299 NSCLC line cooperate during collective tumor invasion in vitro; while H1299 pack leaders are heavily dependent on oxidative phosphorylation, H1299 pack followers are more reliant on glycolysis. To further dissect how intratumoral heterogeneity enables cancer progression to metastasis, we incorporate high resolution imaging, stable fluorescent labeling, gene editing, and in vitro tumor invasion models to interrogate mechanisms of metabolic cooperation between heterogeneous NSCLC subpopulations. We hypothesize that cooperation and communication between these distinct metabolic subpopulation drives metastatic tumor progression. To determine mechanisms of metabolic cooperativity between subpopulations, we stably transduced our subpopulations to fluorescently label either the mitochondria (through TOM20 labeling) or a key enzyme in glycolysis (through glucose 6-phosphate isomerase GPI labeling), cultured labeled subpopulations with unlabeled subpopulations, and observed metabolic changes and exchange via time-lapse, fluorescence microscopy and flow cytometry in 2D culture conditions. Next steps include visualizing the metabolic cooperation that occurs in conditions mimicking the tumor microenvironment (i.e., 3D invasion assays) using super-resolution microscopy. Taken together, we have developed a method of temporally visualizing metabolic exchange with high spatial resolution between NSCLC subpopulations to investigate the underlying mechanisms enabling successful cell invasion in a variety of tumor microenvironments. Thus far, we have discovered multiple broad mechanisms of exchange including tunneling nanotubes and extracellular vesicles, both of which are inducible with certain stressors common to the tumor microenvironment.
Citation Format: Isaac E. Robinson, Veronika Matsuk, Mala Shanmugam, Janna K. Mouw, Adam I. Marcus. Interrogating metabolic heterogeneity and cooperation in lung cancer collective cell 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 4297.
Abstract 4347: Cell-type specific transcriptional regulation of APOBEC3A in cancers
Authors: Yesudhas Dhanusha , Lone Bilal , Butler Kelly , Chakraborty Arup , Banday Abdul Rouf 
Published: March 2024

Abstract
APOBEC3s (A-H) are a family of seven cytosine deaminases that inactivate viruses as part of the innate immune response. However, APOBEC3A and APOBEC3B have been found to mediate mutagenesis in tumor genomes by deaminating ssDNA that transiently arise during transcription and DNA replication. The mechanisms that trigger these enzymes to generate high mutation burdens in some cancers and affect disease progression and clinical outcomes are largely unknown. Here, we explored cell-type-specific transcriptional regulation of APOBEC3s using single-nucleus/cell RNA-seq (sn/scRNA-seq) data (&gt;100 samples and &gt;300,000 cells) from four tumor types - bladder, lung, breast, and kidney - that display different levels of APOBEC-induced mutation burden. Our analyses revealed that among seven members of the APOBEC3 family, APOBEC3A is expressed in a cell-type-specific manner. The expression was predominant in KRT13 and CDH12 epithelial cell-types and inflamed macrophages. The APOBEC3A+ epithelial cell populations were abundant in the bladder, moderate in the lung and breast, and nearly absent in the kidney tumors. APOBEC3A expression correlated with interferon and pro-inflammatory signaling in KRT13+ cells. Transcription factors ELF3 and ATF3 were significantly upregulated in APOBEC3A+ KRT13 cells. Pseudotime analysis of sn/scRNA-seq data revealed that APOBEC3A cells are in epithelial-mesenchymal transition. Finally, several gene markers defining APOBEC3A+ KRT13 cell types were identified. Ongoing analyses include investigations into clinical correlates, cell-type-specific mutation burdens, and validation through in vitro functional approaches. Our results propose that APOBEC3A is turned on in specific epithelial cell types by multiple signaling pathways during tumorigenesis, thereby driving tumor heterogeneity, particularly in high mutation-burden cancers.
Citation Format: Dhanusha Yesudhas, Bilal Lone, Kelly Butler, Arup Chakraborty, Abdul Rouf Banday. Cell-type specific transcriptional regulation of APOBEC3A in 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 4347.
Abstract 4367: PTEN/AKT signal promotes cholangiocyte fate in liver tumorigenesis by inducing SOX9 overexpression and crosstalk with Notch activation
Authors: Tang Qi , Chen Jingyu , Zeng Ni , He Lina , Chopra Shefali , Alhousari Diala , Nguyen Phillip , Zhang Guo , Stiles Bangyan L. 
Published: March 2024

Abstract
Cholangiocarcinoma (CCA) is the second most dominant primary liver malignancy next to hepatocellular carcinoma (HCC), and among the most mortal among human cancers. The PI3K/AKT signaling pathway was considered a permissive signal for the development of CCA. To explore how the PI3K/AKT signal contributes to CCA development, we deleted Pten, the lipid phosphatase that negatively regulates the PI3K/AKT signal in the liver. The Lv-PTEN (PtenloxP/loxP; Alb-Cre+) mice developed a mixed HCC and CCA tumor phenotype with all mice developing CCA by 12-month age. Treatment of Lv-PTEN mice with DDC at 3 months to obstruct the bile duct leads to an earlier CCA oncogenesis. Deletion of Akt2 in the Lv-PTEN mice (Lv-DM, Akt2loxP/loxP; PtenloxP/loxP; Alb-Cre+) significantly attenuates tumor development. Compared with the Lv-PTEN mice, loss of AKT2 in Lv-DM mice robustly and significantly reduced the expression of SOX9, a cholangiocyte gene. This data suggests that the AKT signal may permit a cholangiocyte fate by inducing SOX9 expression. Supporting the role of PTEN/AKT in permitting a cholangiocyte fate, SOX9 expression is also induced in the livers of mice where Pten deletion is targeted to the hepatocytes via injection of AAV8-TGB-Cre (Hp-PTEN, PtenloxP/loxP; R26RYFP; AAV8-TBG-Cre). Similar to the Lv-PTEN mice, treatment with DDC induced early onset of CCA development in the Hp-PTEN mice. We next explore Notch signal for its crosstalk with PTEN loss that permits CCA development. Notch signal is robustly induced in the tumors of the Lv-PTEN mice and induced with DDC treatment in both Lv-PTEN and Hp-PTEN livers. We showed that exposure to Jag1 ligand-coated extracellular matrix or expression of NICD also induced the expression of SOX9 while DAPT time-dependently attenuated the expression of SOX9. In the Hp-Pten mice treated with DDC, inhibiting the Notch pathway with DAPT attenuated ductal reaction and led to downregulation of SOX9 in the Lv-PTEN livers, suggesting a positive regulatory role of Notch on SOX9. These data support that Notch activation regulates SOX9 and collaborates with PTEN loss to drive cholangiocyte fate and CCA development.
Citation Format: Qi Tang, Jingyu Chen, Ni Zeng, Lina He, Shefali Chopra, Diala Alhousari, Phillip Nguyen, Guo Zhang, Bangyan L. Stiles. PTEN/AKT signal promotes cholangiocyte fate in liver tumorigenesis by inducing SOX9 overexpression and crosstalk with Notch activation [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 4367.
Abstract 4368: USP36 SUMOylates EXOSC10 and Las1L to promotes their function in rRNA processing
Authors: Dai Mushui , Li Yanping , Yang Yunhan , Sun Xiao-Xin 
Published: March 2024

Abstract
Eukaryotic ribosome biogenesis is a highly regulated multistep process to generate ribosomes, including transcription of pre-ribosomal RNA, rRNA processing, ribosome subunit assembly and export. Dysregulation of ribosome biogenesis is associated with various human diseases, including ribosomopathies and cancer. Therefore, it is crucial to understand how ribosome biogenesis is regulated during normal cell homeostasis and how it is deregulated in human diseases. Here, we report that the ubiquitin-specific protease USP36 acts as a novel SUMO ligase to promote nucleolar protein SUMOylation. Using affinity purification, we found that USP36 associates with a large number of nucleolar and ribosome biogenesis-related proteins, including all 10 components of the nucleolar RNA exosome complex, EXOSC1 to EXOSC10, as well as the Las1L-Nol9 endonuclease-kinase complex. We showed that USP36 interacts with the RNA exosome through EXOSC10 and SUMOylates ECOSC10 at Lys 583. Mutating K583 impaired the binding of EXOSC10 to pre-rRNAs and the K583R mutant failed to rescue the defects in rRNA processing and cell growth inhibition caused by knockdown of endogenous EXOSC10. Likewise, USP36 interacts with the Las1L-Nol9 complex and promotes Las1L SUMOylation at K565. In addition, USP36 deubiquitinates Las1L and Nol9 and regulates their protein stability. Mutating K565 does not affect the levels of Las1L and the formation of the Las1L-Nol9 endonuclease-kinase complex. However, induced expression of a K565R mutant of Las1L failed to rescue the defects in rRNA processing and cell growth inhibition caused by knockdown of endogenous Las1L. Together, these results suggest that USP36 plays an important role in regulating ribosome biogenesis by post-translationally regulating the function of RNA exosome and Las1L-Nol9 complexes.
Citation Format: Mushui Dai, Yanping Li, Yunhan Yang, Xiao-Xin Sun. USP36 SUMOylates EXOSC10 and Las1L to promotes their function in rRNA processing [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 4368.
Abstract 4376: The pseudokinase PTK7 is a negative regulator of EPHA2 in colorectal cancer
Authors: Borg Jean-Paul , Dessaux Charlotte , Camoin Luc , Audebert Stéphane , Baudelet Emilie , Daulat Avais 
Published: March 2024

Abstract
Colorectal cancer (CRC) remains a major public health issue. Identification of biomarkers predicting high risk of recurrence and discovery of novel targets for therapy are urgently needed1. The cell surface receptor PTK7 is a poorly described evolutionary conserved member of the receptor tyrosine kinase superfamily that was first identified in human colon carcinoma and melanoma2-3. Accumulated data highlighted the implication of PTK7 in diverse cancer-related signaling pathways4-6 and, despite the lack of kinase activity, anti-PTK7 inhibitors are currently in development at preclinical and clinical stages7-9. The dual aim of this project is to increase the basic knowledge about PTK7 and to evaluate its role in CRC in order to propose in the future novel therapeutics directed against PTK7. With the aim to discover novel PTK7 associated pathways, we used a proximity biotinylation strategy coupled to mass spectrometry in CRC cells. Among the partners identified, we found that the pseudokinase PTK7 interacts with the active receptor tyrosine kinase EphrinA2 (EPHA2). Similarly to PTK7, EPHA2 expression correlates with poor prognosis in CRC10. In this work, we also demonstrate that PTK7 acts as a negative regulator of EPHA2 activation through the promotion of distinct oligomeric protein complexes and the modulation of EPHA2 phosphorylation. We also shed in light on the role of PTK7 in EPHA2 K63-linked ubiquitination and its subsequent endosomal sorting and lysosomal degradation.
References 1 Punt CJ et al, Nat. Rev. Clin. Oncol., 2016; 2 Lhoumeau AC et al, Cell Cycle, 2011; 3 Lhoumeau AC et al, PLoS One, 2015; 4 Puppo F et al, EMBO reports, 2011; 5 Martinez S et al, J. Biol. Chem., 2015; 6 Daulat AM and Borg JP, Trends in Cancer, 2017; 7 Damelin M et al, Sci. Transl. Med., 2017; 8 Jie Y et al, Front. Immunol., 2021; 9 Maitland ML et al, Clin. Cancer. Res., 2021; 10 Dunne P et al, Clin. Cancer. Res., 2016; 11 Cioce M and Fazio VM, Cancers, 2021.
Citation Format: Jean-Paul Borg, Charlotte Dessaux, Luc Camoin, Stéphane Audebert, Emilie Baudelet, Avais Daulat. The pseudokinase PTK7 is a negative regulator of EPHA2 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 4376.
Abstract 4389: The role of Rab5 in epithelial growth factor stimulated E-cadherin internalization in spheroid growth of colon cancer cells
Authors: Wang Yu-Chun , Ching Yu-Chien , Chen Hui-Chun , Cheng Chun-Pu , Ku Chia-En , Lee Shin-Ru , Chao Wei-Ting 
Published: March 2024

Abstract
In epithelial based cancer formation, such as colon cancer, the tumor growth is accompanied with malfunction of cell-cell contact inhibition which is regulated by E-cadherin. However, the dynamics of E-cadherin is complicated, the underlying mechanism in tumor nest growth and collective cell migration is still not clear. Rab5 is the endocytic vesicle protein for the membrane receptor internalization into early endosome. Therefore, this study is to investigate the role of Rab5 in E-cadherin turnover of spheroid formation in colon cancer cells. HT-29 colon cancer cells were used in this study. The cells with less anchorage ability were isolated for spheroid formation. The distribution of Rab5, E-cadherin and focal adhesion kinase were observed by immuno-confocal microscopy. The molecular expressions were analyzed by western blot. HT-29 cells showed well defined epithelial phenotype. In the result of immunostaining, Rab5 was distributed in the cytosol and the cell-cell contacts where it colocalized with E-cadherin. Rab5 was also observed in the cell leading edge, however, not much associated with focal adhesions. When HT-29 cell clusters were stimulated with epidermal growth factor, Rab5 was found abundant in the cell-cell contacts. In cell spheroid that derived from HT-29 cells, Rab5 and E-cadherin co-localization at cell-cell contacts was also increased. Furthermore, when cells were treated with Nocodazole, the tubulin inhibitor blocking tubulin-mediated endocytosis, Rab5 accumulated and colocalized with E-cadherin in the cell leading edge. The results of this study demonstrated Rab5 plays the novel role in E-cadherin turnover upon epidermal growth factor stimulation in the progress of spheroid formation and Rab5 may mediate E-cadherin endocytosis through the cell leading edge.
Citation Format: Yu-Chun Wang, Yu-Chien Ching, Hui-Chun Chen, Chun-Pu Cheng, Chia-En Ku, Shin-Ru Lee, Wei-Ting Chao. The role of Rab5 in epithelial growth factor stimulated E-cadherin internalization in spheroid growth of colon 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 4389.
Abstract 4456: De novo pyrimidine synthesis is a druggable vulnerability for chemotherapy resistant nasopharyngeal carcinoma with wild type IDH1
Authors: Li Yingqin , Zhao Yuheng , Zhang Wuqi , Ou Chunxian , Shen Jiaxi , Ma Jun 
Published: March 2024

Abstract
Chemotherapy resistance is a major obstacle to treat nasopharyngeal carcinoma (NPC), and strategies to overcome this resistance are required. Using proteomic analysis, we found that NPC patients resistant to gemcitabine plus cisplatin (GP) induction chemotherapy were characterized by abundant metabolic pathways. NPC with high expression of wild-type isocitrate dehydrogenase 1 (wtIDH1) was hyperdependent on de novo pyrimidine nucleotide synthesis and resistant to GP. Knockdown of IDH1 augmented the inhibition of de novo pyrimidine nucleotide synthesis induced by gemcitabine and cisplatin but reversed the suppression of purine nucleotide synthesis, which leading to DNA damage caused by nucleotide pool imbalance. IDH1 facilitated transcription of dihydroorotate dehydrogenase (DHODH), a rate-limiting enzyme for de novo pyrimidine nucleotide synthesis, through promoting chromatin accessibility by ALKBH5 in an α-ketoglutaric acid dependent manner. DHODH inhibitor, BAY2402234 significantly sensitized NPC cells to gemcitabine plus cisplatin chemotherapy. Collectively, these results reveal that wtIDH1-induced increase in de novo pyrimidine nucleotide represents a metabolic vulnerability that can be exploited pharmacologically, highlighting BAY2402234 as a promising strategy to enhance the efficacy of chemotherapy against NPC.
Citation Format: Yingqin Li, Yuheng Zhao, Wuqi Zhang, Chunxian Ou, Jiaxi Shen, Jun Ma. De novo pyrimidine synthesis is a druggable vulnerability for chemotherapy resistant nasopharyngeal carcinoma with wild type IDH1 [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 4456.
Abstract 4464: Ferredoxin 1 is essential for embryonic development and lipid homeostasis
Authors: Zhang Jin , Mohibi Sharkur , Chen Xinbin , Perng Vivian , Zhang Yanhong 
Published: March 2024

Abstract
Mammalian ferredoxin 1 and 2 (FDX1/2) belong to an evolutionary conserved family of iron-sulfur cluster containing proteins and act as electron shutters between ferredoxin reductase (FDXR) and numerous proteins involved in critical biological pathways. FDX1 is involved in biogenesis of steroids and bile acids, Vitamin A/D metabolism, and lipoylation of tricarboxylic acid (TCA) cycle enzymes. FDX1 has been extensively characterized biochemically but its role in physiology and lipid metabolism has not been explored. In this study, we generated Fdx1-deficient mice and showed that knockout of both alleles of the Fdx1 gene led to embryonic lethality. We also showed that like Fdxr+/− mice, Fdx1+/− mice had a shorter life span and were prone to steatohepatitis. However, unlike Fdxr+/− mice, Fdx1+/− mice were not prone to spontaneous tumors. Additionally, we showed that FDX1 deficiency led to lipid droplet accumulation possibly via the ABCA1-SREBP1/2 pathway. Specifically, untargeted lipidomic analysis showed that FDX1 deficiency led to alterations in several classes of lipids, including cholesterol, triacylglycerides, acylcarnitines, ceramides, phospholipids and lysophospholipids. Taken together, our data indicate that FDX1 is essential for mammalian embryonic development and lipid homeostasis at both cellular and organismal levels.
Citation Format: Jin Zhang, Sharkur Mohibi, Xinbin Chen, Vivian Perng, Yanhong Zhang. Ferredoxin 1 is essential for embryonic development and lipid homeostasis [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 4464.
Abstract 4465: Galectin-1 regulates CD147 and downstream pathways critical for glioma progression
Authors: Guda Maheedhara R. , Tsung Andrew J. , Asuthkar Swapna , Velpula Kiran 
Published: March 2024

Abstract
Galectin-1 (Gal-1) is an important protein for glioma progression and glioma stem cell maintenance. Gal-1 may act through CD147, a potential Gal-1 receptor. CD147, also known as Basigin or extracellular matrix metalloproteinase inducer (EMMPRIN), is a transmembrane glycoprotein highly expressed in various cancer cells. An analysis utilizing the Gliovis database and encompassing 667 Glioblastoma Multiforme (GBM) patients segregated based on median CD147 expression levels delineated cohorts with above-median (n=339) and below-median (n=328) CD147 expression. Kaplan-Meier survival curves unveiled a significant association between heightened CD147 expression and reduced overall survival (OS) in this patient population. Experimental approaches employing immunoblotting and immunohistochemistry techniques on shGal-1 treated cell lysates and mouse brain samples exhibited decreased CD147 expression compared to respective controls. Additionally, immunocytochemical studies corroborated an augmented colocalization of Gal-1 and CD147, with a subsequent reduction in this association following shGal-1 treatment. Next, we used AC-73, a selective CD147 inhibitor, to determine the levels of CD147 and Gal-1. Treatment with 20μM AC-73 and siRNA for CD147 showed reduced CD147 levels in GSC33 and GSC20 cells while maintaining unaltered Gal-1 expression. Inhibiting CD147 did not affect Gal-1 levels, further suggesting Gal-1 acts upstream. CD147 activates matrix metalloproteinase-9 (MMP9), and CD147 knockdown reduced MMP9 levels, elucidating a Gal-1-CD147-MMP9 pathway. Overall, Gal-1 appears to act upstream of CD147 to regulate MMP9, integrins, and other factors important for glioma progression. Further elucidation of these pathways will provide insights into glioma biology and potential therapeutic targets.
Citation Format: Maheedhara R. Guda, Andrew J. Tsung, Swapna Asuthkar, Kiran Velpula. Galectin-1 regulates CD147 and downstream pathways critical for glioma progression [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 4465.