tbuckley/cabot-search huggingface dataset:
Abstract LT05: METTL8-MEDIATED EPITRANSCRIPTOMIC REGULATION OF GBM CYCLING STATE IS DEPENDENT ON RTK/PI3K/AKT SIGNALING
Authors: Bernice Woon Li Lee, You Heng Chuah, Jeehyun Yoon, Oleg V. Grinchuk, Jia Feng, Yajing Liang, Jayshree L Hirpara, Ya Ting Shen, Loo Chien Wang, Yan Ting Lim, Tianyun Zhao, Radoslaw M Sobota, Tan Boon Toh, Shazib Pervaiz, Zhewang Lin, Derrick Sek Tong Ong
Journal: Cancer Research (2024)

Abstract Glioblastoma (GBM) is a lethal brain tumor with limited treatment options. Treatment failures are often attributed to the existence of glioma stem cells (GSCs), which confer intratumoral heterogeneity and therapy resistance. Contrary to common belief that cancer cells employ aerobic glycolysis (Warburg effect) to sustain their metabolic requirements, GSCs rely on oxidative phosphorylation (OXPHOS) for energy production. As a result, GSCs are uniquely sensitive to OXPHOS inhibitors (Gboxin), as well as mitochondrial translation inhibitors which disrupt OXPHOS. METTL8 is a newly discovered mitochondrial methyltransferase which catalyzes m3C32 modifications in mitochondrial tRNAsThr/Ser(UCN) (mt-tRNAs). This post-transcriptional modification ensures the optimal structure of mt-tRNAs to facilitate efficient translation of mitochondrial proteins involved in electron transport chain (ETC). Although the epitranscriptomic functions of METTL8 have been well characterized, its roles in cancers (i.e. glioblastoma) remain largely unexplored. In this study, we showed that METTL8 is overexpressed in GBM and high METTL8 expression portends poor patient prognosis. In GSC, METTL8 is under the transcriptional regulation of HIF-1α, and the chromatin accessibility at METTL8 promoter is facilitated by the deposition of histone variant H2AZ. METTL8 depletion downregulated m3C32 modifications in mt-tRNAsThr/Ser(UCN) in GSC, leading to impaired mitochondrial translation and OXPHOS defects. Phenotypically, METTL8 knockdown (KD) compromised GSCs’ self-renewal, proliferation, invasiveness and tumorigenicity. Interestingly, METTL8-KD GSC acquired a slow cycling state which is linked to reduced receptor tyrosine kinase (RTK) signaling. Consistently, METTL8-KD GSC showed lower Akt phosphorylation and exhibited increased sensitivity to mTOR/Akt inhibitors. Finally, our mechanistic findings led to the identification of a novel HIF1-α/Akt inhibitor drug combination which faithfully recapitulates the phenotypes of METTL8-KD GSCs. In conclusion, our findings provide the first in-depth study of METTL8 roles in GBM pathogenesis, and highlights a novel drug combination which could potentially be used to treat this dreadful disease. Citation Format: Bernice Woon Li Lee, You Heng Chuah, Jeehyun Yoon, Oleg V. Grinchuk, Jia Feng, Yajing Liang, Jayshree L Hirpara, Ya Ting Shen, Loo Chien Wang, Yan Ting Lim, Tianyun Zhao, Radoslaw M Sobota, Tan Boon Toh, Shazib Pervaiz, Zhewang Lin, Derrick Sek Tong Ong. METTL8-MEDIATED EPITRANSCRIPTOMIC REGULATION OF GBM CYCLING STATE IS DEPENDENT ON RTK/PI3K/AKT SIGNALING [abstract]. In: Proceedings of Frontiers in Cancer Science; 2023 Nov 6-8; Singapore. Philadelphia (PA): AACR; Cancer Res 2024;84(8_Suppl):Abstract nr LT05.
Abstract P24: Elucidating the Mechanism of Action of Lenvatinib in Estrogen Receptor-Positive (ER+) Breast Cancer
Authors: Natasha Gandasasmita, Gauri Vaidya, Arpita Datta, Charlie Marvalim, Joline Si Jing Lim, Soo Chin Lee
Journal: Cancer Research (2024)

Abstract Background: ER+ breast cancer is the most common subtype of breast cancer. Although most patients respond initially to endocrine therapy (ET), endocrine resistance inevitably develops, leading to disease progression. Lenvatinib, a multi-kinase inhibitor, demonstrated clinical benefit in the treatment of patients with advanced ER+ breast cancer who have progressed on ET in a phase Ib/II clinical trial from our group. Our study aims to elucidate the molecular mechanism of action of lenvatinib in ER+ breast cancer. Methods: A cell viability assay was performed to assess the sensitivity of four ER+ cell lines to lenvatinib. Western blot was used to elucidate its effect on downstream pathway signalling, and cell cycle arrest investigated through flow cytometry. A series of functional assays, including BrdU, colony formation and wound-healing assays assessed proliferative, clonogenic and migratory activity respectively. The effect of lenvatinib on epithelial-mesenchymal transition (EMT) was analysed using RT-qPCR, and compared with siRNA knockdown (KD) of Fgfr1 and Fgfr2. Results: ER+ cell lines demonstrated sensitivity to lenvatinib in the micromolar range. Western blot showed downregulation of FGFR1, FGFR2, pERK and pAKT expression post-treatment. Lenvatinib was found to induce a G1 phase arrest, suppressed cell proliferation in a dose-dependent manner, and diminished both the clonogenic ability and migratory activity of ER+ cells. Lenvatinib treatment reduced expression of Fgfr1, Fgfr2 and the mesenchymal markers N-cad and Fibronectin, while increasing the expression of the epithelial markers E-cad and Claudin-1, indicating potential inhibition of EMT. A similar change in EMT marker expression was observed in Fgfr1 KD but not Fgfr2 KD cells. Conclusion: Lenvatinib demonstrated potent anti-cancer activity and induction of G1 phase arrest, leading to decreased cell proliferation, reduction of clonogenic ability and cell migration. EMT inhibition was also observed, possibly through the FGFR1 signalling pathway. Citation Format: Natasha Gandasasmita, Gauri Vaidya, Arpita Datta, Charlie Marvalim, Joline Si Jing Lim, Soo Chin Lee. Elucidating the Mechanism of Action of Lenvatinib in Estrogen Receptor-Positive (ER+) Breast Cancer [abstract]. In: Proceedings of Frontiers in Cancer Science; 2023 Nov 6-8; Singapore. Philadelphia (PA): AACR; Cancer Res 2024;84(8_Suppl):Abstract nr P24.
Abstract P66: Off-The-Shelf Epstein Barr Virus Specific T Cells Armored with B7-H3-Targeting Chimeric Antigen Receptors Is an Effective and Safe Tumor- Agnostic Therapy For B7-H3 Positive Solid Malignancies
Authors: Siok Ping Yeo, Lindsay Kua, Jin Wei Tan, Joanna Kristyn Lim, Fiona Wong, May Delos Santos, Chek Meng Poh, Angeline Goh XH, Xin Yu Koh, Xiao Hua Zhou, Rajarethinam R, Qing Feng Chen, Zhisheng Her, Ivan D Horak, Lionel Low, Kar Wai Tan
Journal: Cancer Research (2024)

Abstract In contrast to its limited expression in normal tissues, the B7 homolog 3 protein (B7-H3) is over-expressed in many human tumors, making it an attractive target for chimeric antigen receptor (CAR) T cell therapy. To address the technical challenges limiting broader patient access to autologous CAR T cell therapy, we armoured Epstein-Barr Virus Specific T Cells (EBVSTs) with CARs as an off-the-shelf therapy against solid tumors. We identified and utilised a nanobody as the domain specifically targeting B7-H3 in our CAR construct to reduce the stability issues associated with scFv-based domains. Our B7H3.CAR armored EBVSTs demonstrated potent in-vitro and in-vivo activity against multiple B7-H3 positive tumor and patient-derived xenografts models. Analysis of human healthy tissues and tumors microarrays indicated that B7-H3 expression, while elevated in patient tumors, was differentially low in healthy tissues. Consistent with this, mouse T cells expressing a murine equivalent of our B7H3.CAR displayed good on-target off-tumor safety in immunocompetent mice bearing syngeneic tumors. Further in-vitro evaluation revealed that while human T, B and NK cells were unaffected by B7H3.CAR EBVSTs targeting, monocytes were readily targeted due to the upregulation of B7-H3. Consequent to this targeting and depletion of B7-H3 positive human myeloid cells which are key mediators of CRS, a low incidence of cytokine release syndrome was observed in humanized mice after B7H3.CAR EBVST treatment. Lastly, we showed that B7H3.CAR EBVSTs can target myeloid-derived suppressor cells (MDSCs) that express B7-H3 and in doing so, alleviate MDSC-driven immune suppression. Our findings demonstrate that our nanobody-based B7H3.CAR EBVSTs present not only an effective and safe off-the-shelf approach for targeting any B7-H3-positive solid tumor while also addressing challenges that hindered the clinical development of CAR T cells in such indications. Citation Format: Siok Ping Yeo, Lindsay Kua, Jin Wei Tan, Joanna Kristyn Lim, Fiona Wong, May Delos Santos, Chek Meng Poh, Angeline Goh XH, Xin Yu Koh, Xiao Hua Zhou, Rajarethinam R, Qing Feng Chen, Zhisheng Her, Ivan D Horak, Lionel Low, Kar Wai Tan. Off-The-Shelf Epstein Barr Virus Specific T Cells Armored with B7-H3-Targeting Chimeric Antigen Receptors Is an Effective and Safe Tumor- Agnostic Therapy For B7-H3 Positive Solid Malignancies [abstract]. In: Proceedings of Frontiers in Cancer Science; 2023 Nov 6-8; Singapore. Philadelphia (PA): AACR; Cancer Res 2024;84(8_Suppl):Abstract nr P66.
Abstract P10: p44, the Amino-terminal Lacking Isoform of p53, is Dispensable for Tumor Suppression but Regulates Male Fertility
Authors: RH Chia, Beng Hooi Phang, Fanny Xueting Teo, Hannah Lau, Kanaga Sabapathy
Journal: Cancer Research (2024)

Abstract p53 is the most studied tumor-suppressor, by virtue of its functional inactivation in most human cancers. One aspect that has not received sufficient attention is the function of the various forms of p53, such as p47, that lacks the amino-terminal transactivation domain. Hence, the goal of this work has been to systematically characterize p47, which was found to retain the ability to selective transactivate apoptotic target gene activation (and thus the ability to induce apoptosis), but lacks the ability to induce the expression of genes involved in cell cycle arrest. Consistently, patients with tumors that have p53 mutations that lead to p47 expression have a better prognosis. We have uncovered the mechanistic basis of the selective transcriptional activity of p47, which is associated with selective co-factor binding. In addition, we have generated mice that express only p47 (without p53), and show that they are susceptible to spontaneous tumors, like human patients who have germ-line mutations that lead to only p47 expression. Thus, p47 appears to be a null allele in mice with respect to tumor formation, and is incapable of inducing selective target gene activation nor apoptosis, highlighting species-specific differences in its functionality. Further characterization of these mice will be reported. Citation Format: RH Chia, Beng Hooi Phang, Fanny Xueting Teo, Hannah Lau, Kanaga Sabapathy. p44, the Amino-terminal Lacking Isoform of p53, is Dispensable for Tumor Suppression but Regulates Male Fertility [abstract]. In: Proceedings of Frontiers in Cancer Science; 2023 Nov 6-8; Singapore. Philadelphia (PA): AACR; Cancer Res 2024;84(8_Suppl):Abstract nr P10.
Intention-to-treat outcomes utilising a stringent event definition in children and young people treated with tisagenlecleucel for r/r ALL through a national access scheme
Authors: Macarena Oporto Espuelas, Saskia Burridge, Amy A. Kirkwood, Denise Bonney, Kelly Watts, Geoff Shenton, Katarzyna A. Jalowiec, Maeve A. O’Reilly, Claire Roddie, Anna Castleton, Katherine Clesham, Emma Nicholson, Rajesh Alajangi, Shilpa Prabhu, Lindsay George, Ben Uttenthal, Maria Gabelli, Lorna Neill, Caroline Besley, Sridhar Chaganti, Robert F. Wynn, Jack Bartram, Robert Chiesa, Giovanna Lucchini, Vesna Pavasovic, Anupama Rao, Kanchan Rao, Juliana Silva, Sujith Samarasinghe, Ajay Vora, Peter Clark, Michelle Cummins, David I. Marks, Persis Amrolia, Rachael Hough, Sara Ghorashian
Journal: Blood Cancer Journal (2024)

Abstract CAR T-cell therapy has transformed relapsed/refractory (r/r) B-cell precursor acute lymphoblastic leukaemia (B-ALL) management and outcomes, but following CAR T infusion, interventions are often needed. In a UK multicentre study, we retrospectively evaluated tisagenlecleucel outcomes in all eligible patients, analysing overall survival (OS) and event-free survival (EFS) with standard and stringent definitions, the latter including measurable residual disease (MRD) emergence and further anti-leukaemic therapy. Both intention-to-treat and infused cohorts were considered. We collected data on feasibility of delivery, manufacture, toxicity, cause of therapy failure and followed patients until death from any cause. Of 142 eligible patients, 125 received tisagenlecleucel, 115/125 (92%) achieved complete remission (CR/CRi). Severe cytokine release syndrome and neurotoxicity occurred in 16/123 (13%) and 10/123 (8.1%), procedural mortality was 3/126 (2.4%). The 2-year intent to treat OS and EFS were 65.2% (95%CI 57.2–74.2%) and 46.5% (95%CI 37.6–57.6%), 2-year intent to treat stringent EFS was 35.6% (95%CI 28.1–44.9%). Median OS was not reached. Sixty-two responding patients experienced CAR T failure by the stringent event definition. Post failure, 1-year OS and standard EFS were 61.2% (95%CI 49.3–75.8) and 55.3% (95%CI 43.6–70.2). Investigation of CAR T-cell therapy for B-ALL delivered on a country-wide basis, including following patients beyond therapy failure, provides clinicians with robust outcome measures. Previously, outcomes post CAR T-cell therapy failure were under-reported. Our data show that patients can be successfully salvaged in this context with good short-term survival.
Abstract P18: RHBDL2 PROMOTES NON-SMALL CELL LUNG CANCER METASTASIS AND OSIMERTINIB RESISTANCE BY ACTIVATING RAS/MEK/ERK SIGNALING PATHWAY THROUGH INTERACTION WITH FGFR
Authors: Jun Deng, Jia-jia Qin, Neng-ming Lin
Journal: Cancer Research (2024)

Abstract Non-small cell lung cancer (NSCLC) is a highly malignant form of cancer, distinguished by prompt metastasis, restricted response to chemotherapy, and unfavorable prognosis. As a result, there is an imperative requirement to investigate novel therapeutic approaches for NSCLC. Rhomboid-like protein 2 (RHBDL2) is overexpressed in various tumor cells and is associated with poor prognosis. However, the relevance of RHBDL2 to NSCLC remains unclear. This study aims to investigate the potential role of RHBDL2 as a diagnostic and prognostic biomarker for NSCLC, as well as its biological functions and molecular mechanisms in NSCLC. We found that RHBDL2 was highly expressed in human NSCLC cells and tissues, and was significantly correlated with distant metastasis and poor survival of NSCLC patients. Gain- and loss-of-function assays showed that RHBDL2 could accelerate NSCLC metastasis in vitro and in vivo. KEGG/GO enrichment analysis identified that the function of RHBDL2 was significantly associated with the activity of RAS signaling pathway. RNA-Seq results also suggested that RHBDL2 might be involved in the activation of the RAS/MEK/ERK signaling pathway. ERK1/2 inhibitor Ravoxertinib could partially restore the metastatic ability of NSCLC cells mediated by RHBDL2. CO-IP/MS results suggested that RHBDL2 interacted with FGFR. GST-pulldown assay confirmed the above findings. RHBDL2 could directly interact with FGFR and affect its phosphorylation, and promote NSCLC cell migration by activating the downstream RAS/MEK/ERK signaling pathway. In addition, we also found that RHBDL2 was involved in osimertinib resistance through FGFR/RAS pathway. Our study results indicate that RHBDL2 promotes NSCLC cell migration and osimertinib resistance by interacting with FGFR and thereby activating the RAS/MEK/ERK signaling pathway. Moreover, it can serve as a novel diagnostic and prognostic biomarker for NSCLC patients. Citation Format: Jun Deng, Jia-jia Qin, Neng-ming Lin. RHBDL2 PROMOTES NON-SMALL CELL LUNG CANCER METASTASIS AND OSIMERTINIB RESISTANCE BY ACTIVATING RAS/MEK/ERK SIGNALING PATHWAY THROUGH INTERACTION WITH FGFR [abstract]. In: Proceedings of Frontiers in Cancer Science; 2023 Nov 6-8; Singapore. Philadelphia (PA): AACR; Cancer Res 2024;84(8_Suppl):Abstract nr P18.
Abstract LT04: Dissecting Mediator Kinase Activity in Normal Tissue Homeostasis and Cancer
Authors: Marius Dannappel, Danxi Zhu, Claire Sun, Ron Firestein
Journal: Cancer Research (2024)

Abstract Cyclin-dependent kinase 8 (CDK8) and its paralog CDK19, collectively known as Mediator kinase, are part of the multimeric Mediator complex that fine-tune gene expression programs on multiple levels, most notably by controlling transcription factor (TF) activity at promoter- and enhancer regions as well as organising the chromatin landscape. While Mediator kinases have been predominantly studied as a therapeutic target in cancer cells, their functions in a physiologically relevant context remain poorly understood. To study in vivo functions of Mediator, we developed a comprehensive suite of genetically engineered mouse models (GEMMs), including conditional floxed alleles (Cdk8fl/fl/Cdk19fl/fl) and kinase-dead knock-ins (Cdk8D173A/fl/Cdk19D173A/fl), enabling the analysis of scaffolding and kinase-dependent functions of this critical transcriptional module. Herein, we show that Mediator kinase has distinct kinase-dependent functions in modulating homeostasis and tissue lineage specification in diverse organs. Moreover, using a proteo-genomic approach we show that the Mediator Kinase module functionally interacts with the SWI/SNF complex to mediate transcriptional output. Collectively, our work expands the understanding of how Mediator Kinase regulates tissue homeostasis and provides a framework for considering how Mediator Kinase inhibition may be effectively employed in the clinical setting. Citation Format: Marius Dannappel, Danxi Zhu, Claire Sun, Ron Firestein. Dissecting Mediator Kinase Activity in Normal Tissue Homeostasis and Cancer [abstract]. In: Proceedings of Frontiers in Cancer Science; 2023 Nov 6-8; Singapore. Philadelphia (PA): AACR; Cancer Res 2024;84(8_Suppl):Abstract nr LT04.
Abstract P32: Cell Type-specific Genetic Therapy of Cancer, Virus Infection and Mitochondrial Disease
Authors: Pei She Loh (Rachel), Sushmita Poddar, Kaustav Chatterjee, Chiu Jing Wen, Derrick Wee Zan Liang, Fritz Lai, Chen Qingfeng, Volker Patzel
Journal: Cancer Research (2024)

Abstract Cell type-specific gene delivery which restricts gene transfer to therapy-relevant cells, hence reducing unwanted side effects caused by the ectopic expression of transgenes, remains one of the biggest challenges. To mitigate potential off-target effects, we developed a programmable cell type-specific gene therapy using an RNA trans-splicing-based approach for gene replacement therapy or suicide gene therapy that can selectively express therapeutic proteins or suicide signals based on the cell’s endogenous pre-mRNA expression profile. Using the liver as a medical target organ, we developed a hepatocellular carcinoma (HCC)-specific trans-splicing based Herpes simplex virus thymidine kinase (HSVtk)/ganciclovir (GCV) suicide gene therapy approach. We rationally designed suicide RNAs that can target multiple HCC-related pre-mRNA biomarkers thereby increasing the overall concentration of targetable pre-mRNA. For delivery, non-viral redosable dumbbell-shaped DNA vectors were designed, manufactured, and tested in tissue culture cells, in 3D patient-derived xenograft spheroids and in mouse model. For cell-type specific delivery, the conjugation of dumbbell vectors with GalNAc3 residues enabled targeted delivery into hepatoblastoma-derived human tissue culture cells. To deliver nucleic acids into the mitochondria of human cells, we studied the long non-coding β2.7 RNA of the human cytomegalovirus which was previously reported to colocalise with mitochondrial complex I. Using thermodynamic profiling, we identified four thermodynamically conserved structural subdomains within the β2.7 RNA that are responsible for its mitochondrial targeting activity. A vector comprising eight mitochondrial targeting domains exhibited a three times higher mitochondrial targeting activity as compared with the parental β2.7 RNA. The amalgamation of mitochondrial targeting RNA and trans-splicing allows cell type-specific transcription of mRNA which can be delivered into mitochondria for mitochondrial gene therapy. Trans-splicing based gene therapy represent a technology that is highly translational offering promising perspectives towards suicide gene therapy of any cancer types or incurable infections with integrating viruses and may enable cell type-specific mitochondrial gene therapy. Citation Format: Pei She Loh (Rachel), Sushmita Poddar, Kaustav Chatterjee, Chiu Jing Wen, Derrick Wee Zan Liang, Fritz Lai, Chen Qingfeng, Volker Patzel. Cell Type-specific Genetic Therapy of Cancer, Virus Infection and Mitochondrial Disease [abstract]. In: Proceedings of Frontiers in Cancer Science; 2023 Nov 6-8; Singapore. Philadelphia (PA): AACR; Cancer Res 2024;84(8_Suppl):Abstract nr P32.
Shedding light on the smoke: unravelling the impact of smoking cessation on psoriasis development
Authors: Charlotte Näslund-Koch, Lone Skov
Journal: British Journal of Dermatology (2024)

Journal Article Accepted manuscript Shedding light on the smoke: Unraveling the impact of smoking cessation on psoriasis development Get access Charlotte Näslund-Koch, Charlotte Näslund-Koch Department of Dermatology and Allergy, Copenhagen University Hospital - Herlev and Gentofte, Copenhagen, DenmarkDepartment of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark Correspondence: Charlotte Näslund-Koch1 Email:charlotte.sigrid.erika.naeslund.koch@regionh.dk Search for other works by this author on: Oxford Academic Google Scholar Lone Skov Lone Skov Department of Dermatology and Allergy, Copenhagen University Hospital - Herlev and Gentofte, Copenhagen, DenmarkDepartment of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark https://orcid.org/0000-0002-4784-9680 Search for other works by this author on: Oxford Academic Google Scholar British Journal of Dermatology, ljae163, https://doi.org/10.1093/bjd/ljae163 Published: 15 April 2024 Article history Received: 09 April 2024 Accepted: 11 April 2024 Published: 15 April 2024