bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 6040: The CHST11-CP-iron axis contributes to NSCLC stemness
Authors: Li Li-Jie , Chang Wei-Min , Hsiao Michael 
Published: April 2023

Abstract
The emerging advances in cancer therapies have changed the landscape for the treatment, but there are limited treatments options for advanced non-small-cell lung cancer (NSCLC). Cancer stem cell-induced chemoresistance and tumor metastasis accounts for treatment failure and recurrence in NSCLC. Additionally, the up-regulated glycosaminoglycan-chondroitin sulfate (CS) biosynthesis pathway contributes to the mesenchymal state of lung cancer and related to unfavorable prognosis. Previously, we found carbohydrate sulfotransferase 11 (CHST11), a key CS biosynthetic enzyme, was associated with tumor progression and metastasis in NSCLC as well as lung fibrosis. Furthermore, ceruloplasmin (CP) acted as a downstream effector of CHST11 through interferon-γ signaling pathway stimulation and increased NSCLC metastatic features. However, the linkage between metabolic dysregulation and NSCLC stemness remains unclear. Here, we found not only overexpression of CHST11 but also CS-A treatment, the metabolite of CHST11, promoted NSCLC tumor sphere formation, the expression of cancer stemness markers, and transcriptional activities of stemness-related pathways. Iron was a necessary ion in upregulating cancer stemness properties such as tumor-initiation, metastasis and chemoresistance. We found both CHST11 and iron enhanced NSCLC tumorigenesis. Moreover, iron chelation disrupted CHST11-CP axis induced-stemness. The combination of iron chelator with chemotherapies showed the synergistic effect on antitumor as well as anti-cancer stemness and further promoted apoptosis. Our findings implicate that the CHST11-CP-iron axis facilitates tumor progression and cancer stemness in NSCLC. A regimen that combines an iron chelator and chemotherapies targeting cancer stem cells will benefit for not only preventing NSCLC tumorigenesis but cancer recurrence.
Citation Format: Li-Jie Li, Wei-Min Chang, Michael Hsiao. The CHST11-CP-iron axis contributes to NSCLC stemness. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6040.
Abstract 6047: ZFTA-RELA fusion aberrantly drives glutamine metabolism in lethal pediatric ependymomas
Authors: Natarajan Siva Kumar , Haggerty-Skeans James , Lum Joanna , Narayanan Pranav , Sweha Stefan , Sunil Sushanth , Panwalkar Pooja , Bayliss Jill , Sajjakulnukit Peter , Dang Derek , Achreja Abhinav , Nagrath Deepak , Lyssiotis Costas , Venneti Sriram 
Published: April 2023

Abstract
Ependymomas are fatal brain malignancies with very few treatment options. More than 70% of supratentorial (ST) ependymomas harbor fusions of the zinc-finger containing, chromatin modifier ZFTA and the transcriptional activator of NF-κB signaling, RELA. Oncogene-driven metabolic reprogramming is a fundamental hallmark of cancer that enables sustained tumor proliferation. ZFTA-RELA fusion protein is essential for tumorigenesis and our goal is to determine how it drives metabolism in ST-ependymomas. To address this, we developed an in vitro isogenic system by expressing the ZFTA-RELA fusion protein in immortalized mouse neural stem cells (ZFTA-RELAFUS). Using this system, we show that these tumor cells selectively upregulate expression of the glutamine transporter (SLC1A5), glutaminase (GLS), and many downstream enzymes in the glutamine metabolic pathway. Therefore, we hypothesized that the ZFTA-RELA fusion drives glutamine metabolism in ST-ependymomas. We further demonstrate that ZFTA-RELAFUS tumor cells utilize glutamine to maintain redox homeostasis and show marked cell death upon its withdrawal. Moreover, JHU-083, a specific pharmacologic inhibitor of glutaminase, killed ZFTA-RELAFUS tumor cells in vitro and in vivo. To summarize, our results suggest that the ZFTA-RELA fusion expressing tumor cells exhibit strong glutamine dependence, and targeting it has significant therapeutic relevance.
Citation Format: Siva Kumar Natarajan, James Haggerty-Skeans, Joanna Lum, Pranav Narayanan, Stefan Sweha, Sushanth Sunil, Pooja Panwalkar, Jill Bayliss, Peter Sajjakulnukit, Derek Dang, Abhinav Achreja, Deepak Nagrath, Costas Lyssiotis, Sriram Venneti. ZFTA-RELA fusion aberrantly drives glutamine metabolism in lethal pediatric ependymomas [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6047.
Abstract 6070: Comprehensive real-world-data based molecular profiling and mapping of non-squamous NSCLC patients to immune-checkpoint-inhibitor biomarkers
Authors: Kloetgen Andreas , Wang Danyi , Coenen-Stass Anna , Gounaris Ioannis , Hopkins Julia F. , Locatelli Giuseppe , Scheuenpflug Juergen , Feng Zheng 
Published: April 2023

Abstract
Purpose: Non-squamous non-small cell lung cancer (nsqNSCLC) patients without detectable actionable alterations in EGFR, ALK, or ROS1, have a diverse genetic background. These patients are eligible to and usually receive untargeted, first line immune checkpoint inhibitors (ICI) and/or chemotherapy with heterogeneous outcomes. To identify potential predictive biomarkers for the stratification of nsqNSCLC patients without actionable genetic alterations, a comprehensive molecular profiling of this subpopulation was performed using the Foundation Medicine genomic database.
Methods: Molecular profiles from 53,119 nsqNSCLC patients were analyzed using the FoundationInsightsTM web platform. After the patients with known and likely functional short variants for EGFR and fusions for ALK and ROS1 were excluded, the prevalences for commonly altered genes were determined. Pathway analysis was conducted with Metascape. Statistical significance and enrichment in PD-L1 and tumor mutation burden (TMB) biomarker overlap with altered genes was calculated using a fisher exact test against an alteration negative cohort.
Results: nsqNSCLC patients without actionable genetic alterations can be described as a heterogenous population with different genetic alterations. We found a total of 103 genes with an individual, minimal prevalence of &gt;1% to be the major descriptors that collectively were found in most patients of the nsqNSCLC subpopulation. These genes relate to pathways involved in cell cycle, cell proliferation, response to growth factors or chromatin organization. Out of the most frequently altered genes, we identified those that are associated with PD-L1 or TMB high status for which ICI treatment is most effective in nsqNSCLC.
Conclusions: The results supported the lack of a general association with high PD-L1 and high TMB calls for biomarker informed treatment options for nsqNSCLC patients. We reported a subpopulation of nsqNSCLC patients that can be described by certain genetic alteration, of which some were associated with ICI-related biomarkers for which patients might benefit from a future precision oncology approach utilizing combined targeted and ICI treatment.
Citation Format: Andreas Kloetgen, Danyi Wang, Anna Coenen-Stass, Ioannis Gounaris, Julia F. Hopkins, Giuseppe Locatelli, Juergen Scheuenpflug, Zheng Feng. Comprehensive real-world-data based molecular profiling and mapping of non-squamous NSCLC patients to immune-checkpoint-inhibitor biomarkers. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6070.
Abstract 6107: Novel roles for AMBRA1 in regulating DNA double-strand breaks
Authors: Jiang Yuning , Abbas Tarek 
Published: April 2023

Abstract
AMBRA1 (Activating Molecule in Beclin-1-Regulated Autophagy) is a tumor suppressor protein whose expression is downregulated in several human malignancies. AMBRA1 was recently found to function as a substrate receptor for the cullin-4-based ubiquitin ligase (CRL4AMBRA1) that promotes the ubiquitin-dependent proteolysis of D-type cyclins (cyclin D1, D2 and D3); this serves to guard against premature S-phase entry and replication stress, providing a potential mechanism for its tumor suppressive activity. Cyclin D1 protein, which is stabilized, along with cyclin D2 and D3, in AMBRA1-deficient cells, has been shown to promote homologous recombination (HR) repair of DNA double-strand breaks (DSBs), suggesting that AMBRA1 may be additionally involved in the repair of DSBs. Using our recently published CRISPR-Cas9-based dual fluorescent reporter assay system, we show that while the loss of AMBRA1 increased D-type cyclins and Rb hyperphosphorylation as expected, it did, surprisingly, inhibit HR-mediated repair and stimulated error-free non-homologous end-joining (NHEJ), and that both of these new activities are independent of cyclin D1 or RB1. High-throughput sequencing of DSB repair junctions confirm these results and shows significant depletion of indels with reduction in microhomology-mediated end-joining in AMBRA1-deficient cells, suggesting that AMBRA1 plays a role in promoting resection at DSBs. In support of this hypothesis, we found that the loss of AMBRA1 reduces RAD51 recruitment to DSBs in cells exposed to ionizing radiation. Consistent with its role in promoting HR, we found that AMBRA1-deficient cells are significantly more sensitive to PARP inhibitors compared to AMBRA1-proficient cells. In summary, we show that AMBRA1 is a novel regulator of DSBs, and that its downregulation in cancer cells and tumors render cancer cells susceptible to inhibition by PARP inhibitors.
Citation Format: Yuning Jiang, Tarek Abbas. Novel roles for AMBRA1 in regulating DNA double-strand breaks. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6107.
Abstract 6111: Design of a small molecule screening assay to detect DNA trapping of PARP1/2
Authors: Zientara-Rytter Kasia , Baron Veronique T. , Park Junguk , Shashkin Pavel , Zhu Henry 
Published: April 2023

Abstract
Poly(ADP-ribose) polymerase (PARP) inhibitors are currently used in the clinic for the treatment of tumors with a defective DNA damage response (DDR). When PARP1 or PARP2 binds damaged DNA, it adds poly(ADP-ribose) chains to its own backbone and to other DDR proteins, which recruits and activates them. PARylated PARP1/2 next detaches from the DNA so that the other PARylated proteins can initiate the repair process. It has been observed that some PARP inhibitors prevent PARP1/2 from dissociating the DNA. The continuous presence of PARP at the site of damage prevents repair and blocks replication, leading to cell death. Therefore, drugs that trap PARP1/2 to the DNA tend to be significantly more cytotoxic than other PARP inhibitors, which is highly desirable. This study describes the design and optimization of novel PARPtrap assays to specifically assess the ability of a drug to trap PARP onto DNA. The assay is based on principles of fluorescence polarization and uses fluorescently labeled DNA probes that are excited by polarized light and emit light with a degree of polarization that is proportional to the rate of molecular rotation. The free DNA probes that rotate fast have low fluorescence polarization (FP), but high FP when are bound to PARP1 or PARP2. When NAD+ is added, the PARylated enzymes detach from the probe, reducing FP levels. If a PARP inhibitor is added, the inhibitor’s trapping ability increases FP in a dose-dependent manner. Proof-of-principle titration of known PARP-trapping inhibitors (Talazoparib, AZD305, Olaparib and Veliparib) was performed to validate the assay. We observed that: i)The known relative trapping efficacies of Talazoparib, Olaparib and Veliparib were similar to known relative efficacies. ii)Talazoparib, Olaparib and Veliparib had similar trapping efficacy against PARP1 and PARP2, as measured by their EC50, whereas AZD305 was 1,000 times more efficient at trapping PARP1 than it was PARP2, demonstrating selectivity between PARP1 and PARP2. iii)AZD305 displayed as efficient DNA trapping activity toward PARP1 as best-in-class Talazoparib. In summary, we have designed an innovative PARPtrap assay designed for the high throughput screening of small molecule libraries to specifically identify or compare inhibitors that are capable of trapping PARP1 and/or PARP2 onto DNA.
Citation Format: Kasia Zientara-Rytter, Veronique T. Baron, Junguk Park, Pavel Shashkin, Henry Zhu. Design of a small molecule screening assay to detect DNA trapping of PARP1/2 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6111.
Abstract 6124: Recombinant apurinic/apyrimidinic endonuclease-1/redox factor-1 plus acetylsalicylic acid combination therapy inhibits tumorigenesis in an orthotopic xenograft murine model of triple-negative breast cancer
Authors: Lee Yu Ran , Joo Hee Kyoung , Lee Eun-Ok , Kim Sungmin , Jin Hao , Choi Yeon Hee , Choi Eun Ju , Jeon Byeong Hwa 
Published: April 2023

Abstract
Triple-negative breast cancer (TNBC) is characterized with hormone receptor negative and frequently exhibits inherently aggressive clinical behavior, resulting in poor prognoses. TNBCs are highly heterogenic, leading to obstacles in identifying new therapeutic targets and performing targeted therapy. Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/Ref-1), a multifunctional protein, is mainly involved in DNA repair and redox regulation; it is upregulated in various cancers and is extracellularly secreted because of hyperacetylation. We previously reported that hyperacetylation induced APE1/Ref-1 release causes apoptosis in TNBCs. In the current study, we aimed to assess the therapeutic efficacy of combination treatment involving recombinant human APE1/Ref-1 (rhAPE1/Ref-1) plus acetylsalicylic acid (ASA) in TNBC xenograft mice. ASA co-treatment was used to induce and lasting acetylation of rhAPE1/Ref-1. For in vivo analysis, we constructed an orthotopic xenograft in vivo model of TNBC by using MDA-MB-231 cells. We performed combination therapy involving intravenous injection of purified rhAPE1/Ref-1 (1 mg/kg) and oral administration of ASA (20 mg/kg) thrice a week for 6 weeks in TNBC xenograft mice. This rhAPE1/Ref-1 plus ASA combination therapy inhibited tumor formation and growth, without damaging liver or kidney tissue, and decreased plasma levels of the cancer marker CEA and breast cancer-specific markers CA27-29 and CA15-3 in the TNBC xenograft mice. The TNBC group, which underwent combination therapy, had more apoptotic cells and greater inflammatory cell infiltration in tumor tissues than the vehicle group did. Additionally, in tumor tissue of TNBC with combination therapy exhibits increased apoptosis following upregulation of Bax, cleaved-caspase-3, and cleaved-PARP. Thus, we found that rhAPE1/Ref-1 plus ASA combination therapy enhanced antitumor effects in TNBCs via inflammatory cell infiltration and apoptosis signaling pathways. Our findings indicate the therapeutic potential of rhAPE1/Ref-1 plus ASA combination therapy for TNBC.
Citation Format: Yu Ran Lee, Hee Kyoung Joo, Eun-Ok Lee, Sungmin Kim, Hao Jin, Yeon Hee Choi, Eun Ju Choi, Byeong Hwa Jeon. Recombinant apurinic/apyrimidinic endonuclease-1/redox factor-1 plus acetylsalicylic acid combination therapy inhibits tumorigenesis in an orthotopic xenograft murine model of triple-negative breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6124.
Abstract 6126: Antitumor effect of Iso-mukaadial acetate in MCF-7 human cancer xenograft models
Authors: Raphela-Choma Portia , Motadi Lesetja R. , Choene Mpho S. 
Published: April 2023

Abstract
Antitumor drugs used today have shown significant efficacy and are derived from natural products such as plants. Iso-mukaadial acetate has previously been shown to possess anticancer properties by inducing apoptosis. The purpose of this study was to investigate the therapeutic effect of Iso-mukaadial acetate in the breast cancer xenograft mice model. Female athymic mice were used and were inoculated with breast cancer cells subcutaneously after culturing. Group one served as a negative control group (no treatments) and group two positive control group (cisplatin) which was administered intravenously. Iso-mukaadial acetate treatment was administered orally to group three(100 mg/kg) and group four (500 mg/kg). Blood was collected (70 µL) from the tail vein on day zero, day seven and day 14. Tumor regression was measured, and a pharmacokinetic study was conducted. Estimation of Serum Parameters for Hepatic and Renal Indices were examined using an Automated Chemistry Analyzer. Histopathological analysis was conducted to evaluate morphological changes before and after treatment under a light microscope. Tumor shrinkage was observed after treatment. In conclusion, Iso-mukaadial acetate inhibited tumor progression in breast cancer athymic mice without major side effects.
Citation Format: Portia Raphela-Choma, Lesetja R. Motadi, Mpho S. Choene. Antitumor effect of Iso-mukaadial acetate in MCF-7 human cancer xenograft models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6126.
Abstract 6145: Alternative splicing of GSDMB modulates killer lymphocyte-triggered pyroptosis
Authors: Kong Qing , Xia Shiyu , Pan Xingxin , Ye Kaixiong , Li Zhouyihan , Li Haoyan , Sahni Nidhi , Yi S. Stephen , Liu Xing , Wu Hao , Lieberman Judy , Zhang Zhibin 
Published: April 2023

Abstract
Killer lymphocyte-mediated tumor cell killing is a vital and final step of anti-tumor protective immunity. Killer cells, including cytotoxic CD8 T cells and Natural Killer (NK) cells, deliver granzymes (Gzm) into target cells, which normally activates noninflammatory cell death, but becomes inflammatory when target cells express the gasdermin (GSDM) proteins responsible for pyroptosis. GzmA and GzmB cleave and activate GSDMB and GSDME, respectively. However, the role of GSDMB in anti-tumor immunity is unclear - GSDMB pore formation is controversial and GSDMB expression has been linked to both anti- and pro-tumor functions. Here we found that GSDMB splicing variants are functionally distinct. Cleaved N-terminal (NT) fragments of isoforms 3 and 4 caused pyroptosis, but isoforms 1, 2 and 5, which deleted or modified exon 6, did not. Structural analysis based on AlphaFold predictions and the cryoEM structures of GSDMA3 and GSDMD showed that pore formation required the formation of a functional stabilizing belt structural element near the C-terminus of the cleaved N-terminal fragment, which was disrupted in the non-cytotoxic alternatively spliced isoforms. NK attack of GSDMB3-expressing cells caused pyroptosis, but GSDMB4 cells died mostly by apoptosis, and GSDMB1/2 cells died only by apoptosis. GSDMB4 partially resisted NK cell-triggered cleavage, suggesting that only GSDMB3 is fully functional. GSDMB1-3 were the most abundant isoforms in tested cells and were similarly induced by IFNγ and a chemotherapy drug methotrexate. Expression of cytotoxic GSDMB3/4, but not GSDMB1/2, was associated with better outcome in bladder and cervical cancer, suggesting GSDMB-mediated pyroptosis was protective in those tumors. Our study uncovers a novel role of alternative splicing in modulating caner-associated pyroptosis, and suggests that tumors may manipulate GSDMB splicing to avoid pyroptosis. Thus, modulating GSDMB splicing to increase cytotoxic GSDMB variants but suppress non-cytotoxic GSDMB isoforms could improve anti-tumor immunity and have therapeutic utility.
Citation Format: Qing Kong, Shiyu Xia, Xingxin Pan, Kaixiong Ye, Zhouyihan Li, Haoyan Li, Nidhi Sahni, S. Stephen Yi, Xing Liu, Hao Wu, Judy Lieberman, Zhibin Zhang. Alternative splicing of GSDMB modulates killer lymphocyte-triggered pyroptosis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6145.
Abstract 6146: Tumor suppressor p73 primes extrinsic apoptosis via transcriptional activation of DR5 and c-FLIP
Authors: Zhang Shengliang , El-Deiry Wafik S. 
Published: April 2023

Abstract
The tumor suppressor p73 is a member of p53 family. p73 transcriptionally activates p53-targeted genes involved in cell cycle regulation and apoptosis. It is well known that p73 induces cellular apoptosis via the intrinsic apoptotic pathway upon cellular stresses. However, the role of p73 in extrinsic apoptosis is poorly studied. We observed cell cycle arrested at the G1 phase in cells infected with a p73-expressing recombinant adenovirus (Ad-p73). We observed that overexpression of p73 upregulated c-FLIP at the protein level, in addition to DR5 and p21. c-FLIP is an anti-apoptotic factor that inhibits caspase 8/10 activation, thus blocking extrinsic pathway apoptosis. We demonstrated that c-FLIP is a transcriptional target of p73 based on our observations that: 1) p73 increases c-FLIP at mRNA level, 2) p73 binds to the c-FLIP promoter and 3) p73 enhances c-FLIP promoter-driven luciferase expression. We sought to explore whether the upregulation of c-FLIP prevents extrinsic apoptosis in cancer cells following p73 activation. To address this question, p73 was overexpressed in cells by adenovirus infection and c-FLIP was knocked down by siRNA. Overexpression of p73 induced cellular apoptosis in the cells with knockdown of c-FLIP and this effect was blocked by knockdown of caspase 8. Our results suggest that p73 induces extrinsic apoptosis when c-FLIP is depleted in cancer cells. We further found that the knockdown of DR5 inhibited p73-induced apoptosis in c-FLIP-deficient cancer cells. By contrast, PUMA knockdown did not block p73-induced apoptosis. Our results suggest that DR5 is required for cell extrinsic apoptosis in c-FLIP-deficient cancer cells upon p73 activation. p21 is the cyclin dependent kinase inhibitor that leads to cell cycle arrest at the G1/S phase. Knockdown of p21 enhanced cleaved-caspase 8 and cleaved-PARP in c-FLIP-depleted cancer cells treated with Ad-p73. Our results, taken together, suggest that the p73 primes extrinsic apoptosis via DR5 and the priming level appears to be titrated at the level of c-FLIP. Upregulation of c-FLIP decreases the priming level, resulting in cells converting to cell cycle arrest and survival via p21 whereas reduction of c-FLIP leads the primed cancer cells to undergo extrinsic apoptosis upon p73 treatment in cancer cells. Our discovery of p73 transcriptional upregulation of c-FLIP provides a rationale for depleting c-FLIP to improve antitumor efficacy of p73-targeting cancer therapy.
Citation Format: Shengliang Zhang, Wafik S. El-Deiry. Tumor suppressor p73 primes extrinsic apoptosis via transcriptional activation of DR5 and c-FLIP [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6146.