MP04-20 CHARACTERIZATION OF MITOCHONDRIAL DYSFUNCTION IN MODELS OF RENAL ONCOCYTOMA

Abstract

You have accessJournal of UrologyCME1 Apr 2023MP04-20 CHARACTERIZATION OF MITOCHONDRIAL DYSFUNCTION IN MODELS OF RENAL ONCOCYTOMA Lin Lin, Zuoquan Xie, Daiki Ueno, Marta Boeke, Martin Lang, Darryl Martin, Jessica Nouws, Gerald Shadel, and Brian Shuch Lin LinLin Lin More articles by this author , Zuoquan XieZuoquan Xie More articles by this author , Daiki UenoDaiki Ueno More articles by this author , Marta BoekeMarta Boeke More articles by this author , Martin LangMartin Lang More articles by this author , Darryl MartinDarryl Martin More articles by this author , Jessica NouwsJessica Nouws More articles by this author , Gerald ShadelGerald Shadel More articles by this author , and Brian ShuchBrian Shuch More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003215.20AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Renal oncocytoma (RO) is a benign tumor found in up to 25% of resected small renal masses. Identification prior to surgery remains a diagnostic challenge and there are limited methods for pre-operative identification. Although recurring mutations have been identified in genes associated with complex I (NADH Dehydrogenase) of the electron transport chain in RO, the functional significance is unknown due to the lack of available models. Here we aim to use a patient-derived cell line model to investigate how complex I mutations affect mitochondrial function and respiration, hoping that improved characterization could lead to methods of detection of this tumor. METHODS: RO and normal kidney (NK) specimens from patients undergoing surgical resection were obtained. YUOC1 cell line was derived from a 38-year-old female with a 4 cm renal mass during a partial nephrectomy which was pathologically confirmed to be RO. Long-range PCR was performed to sequence tumor and blood mitochondrial DNA (mtDNA). MtDNA content was measured by real-time PCR. Protein levels of Complex I to IV were analyzed using Western Blot. Mitochondrial morphology was examined using electron microscopy. Cellular oxygen consumption rate and extracellular acidification rate were measured by Seahorse XF96 analyzer. Normal kidney cells, YUNK1, were treated with a complex I inhibitor to model Complex I loss. RESULTS: We successfully established a patient-derived RO cell line (YUOC1), which harbored a somatic ND5 mutation (c89_90insA, N30X) with near homoplasmy (>80% mutation frequency). This led to a loss of ND5 expression, loss of complex I activity, and an increased mtDNA content. Cellular respiration of YUOC1 demonstrated near loss of oxidative phosphorylation and reliance on aerobic glycolysis. Supplementation of succinate for complex II was able to increase oxidative phosphorylation, indicating the rest of the cellular respiration chain was relatively intact. Complex I inhibition with rotenone in a normal kidney cell line (YUNK1) recapitulated an upregulation of mitochondrial biogenesis, indicating complex I inhibition is sufficient to cause changes in mitochondrial phenotype in ROs. CONCLUSIONS: This study helps to characterize some of the metabolic changes associated with RO complex I loss which leads to mitochondrial dysfunction and altered cellular respiration. Further development of models will allow future strategies aimed at identification of nutrient dependencies and metabolic imaging to limit surgical resection of small asymptomatic ROs. Source of Funding: AUA Research Scholar Award © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e41 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Lin Lin More articles by this author Zuoquan Xie More articles by this author Daiki Ueno More articles by this author Marta Boeke More articles by this author Martin Lang More articles by this author Darryl Martin More articles by this author Jessica Nouws More articles by this author Gerald Shadel More articles by this author Brian Shuch More articles by this author Expand All Advertisement PDF downloadLoading ...