{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,20]],"date-time":"2026-04-20T05:16:50Z","timestamp":1776662210395,"version":"3.51.2"},"reference-count":36,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,9,27]],"date-time":"2021-09-27T00:00:00Z","timestamp":1632700800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Pharmacol."],"abstract":"<jats:p>Malignant pleural mesothelioma (MPM) is an invasive malignancy that develops in the pleural cavity, and antifolates are used as chemotherapeutics for treating. The majority of antifolates, including pemetrexed (PMX), inhibit enzymes involved in purine and pyrimidine synthesis. MPM patients frequently develop drug resistance in clinical practice, however the associated drug-resistance mechanism is not well understood. This study was aimed to elucidate the mechanism underlying resistance to PMX in MPM cell lines. We found that among the differentially expressed genes associated with drug resistance (determined by RNA sequencing), TYMS expression was higher in the established resistant cell lines than in the parental cell lines. Knocking down <jats:italic>TYMS<\/jats:italic> expression significantly reduced drug resistance in the resistant cell lines. Conversely, <jats:italic>TYMS<\/jats:italic> overexpression significantly increased drug resistance in the parental cells. Metabolomics analysis revealed that the levels of dTMP were higher in the resistant cell lines than in the parental cell lines; however, resistant cells showed no changes in dTTP levels after PMX treatment. We found that the nucleic acid-biosynthetic pathway is important for predicting the efficacy of PMX in MPM cells. The results of chromatin immunoprecipitation-quantitative polymerase chain reaction (ChIP-qPCR) assays suggested that H3K27 acetylation in the 5\u2032-UTR of <jats:italic>TYMS<\/jats:italic> may promote its expression in drug-resistant cells. Our findings indicate that the intracellular levels of dTMP are potential biomarkers for the effective treatment of patients with MPM and suggest the importance of regulatory mechanisms of TYMS expression in the disease.<\/jats:p>","DOI":"10.3389\/fphar.2021.718675","type":"journal-article","created":{"date-parts":[[2021,9,27]],"date-time":"2021-09-27T06:13:09Z","timestamp":1632723189000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":20,"title":["Upregulation of Thymidylate Synthase Induces Pemetrexed Resistance in Malignant Pleural Mesothelioma"],"prefix":"10.3389","volume":"12","author":[{"given":"Yuzo","family":"Sato","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Masaru","family":"Tomita","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tomoyoshi","family":"Soga","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Atsushi","family":"Ochiai","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hideki","family":"Makinoshima","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2021,9,27]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"153","DOI":"10.1007\/s10555-007-9049-z","article-title":"Molecular Basis of Antifolate Resistance","volume":"26","author":"Assaraf","year":"2007","journal-title":"Cancer Metastasis Rev."},{"key":"B2","doi-asserted-by":"publisher","first-page":"e63338","DOI":"10.1371\/journal.pone.0063338","article-title":"Thymidylate Synthase Expression Determines Pemetrexed Targets and Resistance Development in Tumour Cells","volume":"8","author":"Buqu\u00e9","year":"2013","journal-title":"PLoS One"},{"key":"B3","doi-asserted-by":"publisher","first-page":"6599","DOI":"10.1038\/s41388-019-0897-0","article-title":"HDAC7 Regulates Histone 3 Lysine 27 Acetylation and Transcriptional Activity at Super-enhancer-associated Genes in Breast Cancer Stem Cells","volume":"38","author":"Caslini","year":"2019","journal-title":"Oncogene"},{"key":"B4","doi-asserted-by":"publisher","first-page":"422","DOI":"10.1016\/j.molcel.2016.03.033","article-title":"Bivalent Regions of Cytosine Methylation and H3K27 Acetylation Suggest an Active Role for DNA Methylation at Enhancers","volume":"62","author":"Charlet","year":"2016","journal-title":"Mol. Cel"},{"key":"B5","doi-asserted-by":"publisher","first-page":"27","DOI":"10.1038\/bjc.1998.751","article-title":"Preclinical Cellular Pharmacology of LY231514 (MTA): a Comparison with Methotrexate, LY309887 and Raltitrexed for Their Effects on Intracellular Folate and Nucleoside Triphosphate Pools in CCRF-CEM Cells","volume":"78","author":"Chen","year":"1998","journal-title":"Br. J. Cancer"},{"key":"B6","doi-asserted-by":"publisher","first-page":"143","DOI":"10.1016\/j.chest.2016.12.004","article-title":"Malignant Mesothelioma Biomarkers: From Discovery to Use in Clinical Practice for Diagnosis, Monitoring, Screening, and Treatment","volume":"152","author":"Creaney","year":"2017","journal-title":"Chest"},{"key":"B7","doi-asserted-by":"publisher","first-page":"73","DOI":"10.1016\/0304-419x(77)90001-4","article-title":"Thymidylate Synthetase - a Target Enzyme in Cancer Chemotherapy","volume":"473","author":"Danenberg","year":"1977","journal-title":"Biochim. Biophys. Acta"},{"key":"B8","doi-asserted-by":"publisher","first-page":"186","DOI":"10.1016\/j.cell.2018.08.058","article-title":"Targeting Epigenetic Crosstalk as a Therapeutic Strategy for EZH2-Aberrant Solid Tumors","volume":"175","author":"Huang","year":"2018","journal-title":"Cell"},{"key":"B9","doi-asserted-by":"publisher","first-page":"4835","DOI":"10.1158\/0008-5472.can-20-2811","article-title":"Single-cell Analyses Reveal Diverse Mechanisms of Resistance to EGFR Tyrosine Kinase Inhibitors in Lung Cancer","volume":"81","author":"Kashima","year":"2021","journal-title":"Cancer Res."},{"key":"B10","doi-asserted-by":"publisher","first-page":"439","DOI":"10.1038\/jhg.2013.66","article-title":"Histone Modifications for Human Epigenome Analysis","volume":"58","author":"Kimura","year":"2013","journal-title":"J. Hum. Genet."},{"key":"B11","doi-asserted-by":"publisher","first-page":"33","DOI":"10.3892\/or.2012.1799","article-title":"Interaction and Cross-Resistance of Cisplatin and Pemetrexed in Malignant Pleural Mesothelioma Cell Lines","volume":"28","author":"Kitazono-Saitoh","year":"2012","journal-title":"Oncol. Rep."},{"key":"B12","doi-asserted-by":"publisher","first-page":"890","DOI":"10.1038\/nchembio.1084","article-title":"A Selective Inhibitor of EZH2 Blocks H3K27 Methylation and Kills Mutant Lymphoma Cells","volume":"8","author":"Knutson","year":"2012","journal-title":"Nat. Chem. Biol."},{"key":"B13","doi-asserted-by":"publisher","first-page":"2093","DOI":"10.3892\/ijo.2014.2364","article-title":"Downregulation of Thymidylate Synthase with Arsenic Trioxide in Lung Adenocarcinoma","volume":"44","author":"Lam","year":"2014","journal-title":"Int. J. Oncol."},{"key":"B14","doi-asserted-by":"publisher","first-page":"1031","DOI":"10.1016\/j.jtho.2017.04.002","article-title":"Epidemiology of Environmental Exposure and Malignant Mesothelioma","volume":"12","author":"Liu","year":"2017","journal-title":"J. Thorac. Oncol."},{"key":"B15","doi-asserted-by":"publisher","first-page":"289","DOI":"10.1016\/j.ebiom.2019.10.003","article-title":"MYC Predetermines the Sensitivity of Gastrointestinal Cancer to Antifolate Drugs through Regulating TYMS Transcription","volume":"48","author":"Liu","year":"2019","journal-title":"EBioMedicine"},{"key":"B16","doi-asserted-by":"publisher","first-page":"469","DOI":"10.1097\/JTO.0b013e318283da3e","article-title":"Thymidylate Synthase and Folyl-Polyglutamate Synthase Are Not Clinically Useful Markers of Response to Pemetrexed in Patients with Malignant Pleural Mesothelioma","volume":"8","author":"Lustgarten","year":"2013","journal-title":"J. Thorac. Oncol."},{"key":"B17","doi-asserted-by":"publisher","first-page":"eaar3146","DOI":"10.1126\/science.aar3146","article-title":"Allele-specific Epigenome Maps Reveal Sequence-dependent Stochastic Switching at Regulatory Loci","volume":"361","author":"Onuchic","year":"2018","journal-title":"Science"},{"key":"B18","doi-asserted-by":"publisher","first-page":"1129","DOI":"10.3389\/fphar.2018.01129","article-title":"Metabolic Characterization of Antifolate Responsiveness and Non-responsiveness in Malignant Pleural Mesothelioma Cells","volume":"9","author":"Sato","year":"2018","journal-title":"Front. Pharmacol."},{"key":"B19","doi-asserted-by":"publisher","first-page":"3543","DOI":"10.1200\/JCO.2007.15.0375","article-title":"Phase III Study Comparing Cisplatin Plus Gemcitabine with Cisplatin Plus Pemetrexed in Chemotherapy-Naive Patients with Advanced-Stage Non-small-cell Lung Cancer","volume":"26","author":"Scagliotti","year":"2008","journal-title":"J. Clin. Oncol."},{"key":"B20","doi-asserted-by":"publisher","first-page":"e161","DOI":"10.1016\/S1470-2045(18)30100-1","article-title":"Novel Therapies for Malignant Pleural Mesothelioma","volume":"19","author":"Scherpereel","year":"2018","journal-title":"Lancet Oncol."},{"key":"B21","first-page":"1116","article-title":"LY231514, a Pyrrolo[2,3-D]pyrimidine-Based Antifolate that Inhibits Multiple Folate-Requiring Enzymes","volume":"57","author":"Shih","year":"1997","journal-title":"Cancer Res."},{"key":"B22","doi-asserted-by":"publisher","first-page":"431","DOI":"10.1016\/s0006-2952(03)00287-9","article-title":"Induction of Resistance to the Multitargeted Antifolate Pemetrexed (ALIMTA) in WiDr Human colon Cancer Cells Is Associated with Thymidylate Synthase Overexpression","volume":"66","author":"Sigmond","year":"2003","journal-title":"Biochem. Pharmacol."},{"key":"B23","doi-asserted-by":"publisher","first-page":"1236","DOI":"10.1021\/ac990976y","article-title":"Amino Acid Analysis by Capillary Electrophoresis Electrospray Ionization Mass Spectrometry","volume":"72","author":"Soga","year":"2000","journal-title":"Anal. Chem."},{"key":"B24","doi-asserted-by":"publisher","first-page":"488","DOI":"10.1021\/pr034020m","article-title":"Quantitative Metabolome Analysis Using Capillary Electrophoresis Mass Spectrometry","volume":"2","author":"Soga","year":"2003","journal-title":"J. Proteome Res."},{"key":"B25","doi-asserted-by":"publisher","first-page":"6224","DOI":"10.1021\/ac0202684","article-title":"Pressure-assisted Capillary Electrophoresis Electrospray Ionization Mass Spectrometry for Analysis of Multivalent Anions","volume":"74","author":"Soga","year":"2002","journal-title":"Anal. Chem."},{"key":"B26","doi-asserted-by":"publisher","first-page":"279","DOI":"10.1111\/1440-1681.13415","article-title":"Diagnostic and Prognostic Value of Thymidylate Synthase Expression in Breast Cancer","volume":"48","author":"Song","year":"2021","journal-title":"Clin. Exp. Pharmacol. Physiol."},{"key":"B27","doi-asserted-by":"publisher","first-page":"1594","DOI":"10.1038\/bjc.2011.129","article-title":"Thymidylate Synthase as a Determinant of Pemetrexed Sensitivity in Non-small Cell Lung Cancer","volume":"104","author":"Takezawa","year":"2011","journal-title":"Br. J. Cancer"},{"key":"B28","doi-asserted-by":"publisher","first-page":"1505","DOI":"10.1038\/s41598-018-38017-0","article-title":"FOXM1 Modulates 5-FU Resistance in Colorectal Cancer through Regulating TYMS Expression","volume":"9","author":"Varghese","year":"2019","journal-title":"Sci. Rep."},{"key":"B29","doi-asserted-by":"publisher","first-page":"2636","DOI":"10.1200\/JCO.2003.11.136","article-title":"Phase III Study of Pemetrexed in Combination with Cisplatin versus Cisplatin Alone in Patients with Malignant Pleural Mesothelioma","volume":"21","author":"Vogelzang","year":"2003","journal-title":"J. Clin. Oncol."},{"key":"B30","doi-asserted-by":"publisher","first-page":"1163","DOI":"10.1016\/s0006-2952(03)00007-8","article-title":"Decreased Expression of the Reduced Folate Carrier and Folypolyglutamate Synthetase Is the Basis for Acquired Resistance to the Pemetrexed Antifolate (LY231514) in an L1210 Murine Leukemia Cell Line","volume":"65","author":"Wang","year":"2003","journal-title":"Biochem. Pharmacol."},{"key":"B31","doi-asserted-by":"publisher","first-page":"2835","DOI":"10.1002\/ijc.25002","article-title":"An Orthotopic Implantation Mouse Model of Human Malignant Pleural Mesothelioma for In Vivo Photon Counting Analysis and Evaluation of the Effect of S-1 Therapy","volume":"126","author":"Yanagihara","year":"2010","journal-title":"Int. J. Cancer"},{"key":"B32","doi-asserted-by":"publisher","first-page":"183","DOI":"10.1002\/mc.21842","article-title":"Pemetrexed Induces Both Intrinsic and Extrinsic Apoptosis through Ataxia Telangiectasia Mutated\/p53-dependent and -independent Signaling Pathways","volume":"52","author":"Yang","year":"2013","journal-title":"Mol. Carcinog"},{"key":"B33","doi-asserted-by":"publisher","first-page":"475","DOI":"10.1038\/nrc.2017.42","article-title":"Novel Insights into Mesothelioma Biology and Implications for Therapy","volume":"17","author":"Yap","year":"2017","journal-title":"Nat. Rev. Cancer"},{"key":"B34","doi-asserted-by":"publisher","first-page":"228","DOI":"10.1016\/j.canlet.2011.06.006","article-title":"Establishment of Pemetrexed-Resistant Non-small Cell Lung Cancer Cell Lines","volume":"309","author":"Zhang","year":"2011","journal-title":"Cancer Lett."},{"key":"B35","doi-asserted-by":"publisher","first-page":"7431","DOI":"10.1038\/sj.onc.1206946","article-title":"Resistance to Antifolates","volume":"22","author":"Zhao","year":"2003","journal-title":"Oncogene"},{"key":"B36","doi-asserted-by":"publisher","first-page":"1885","DOI":"10.2147\/DDDT.S106412","article-title":"Molecular Mechanisms of Cisplatin Resistance in Cervical Cancer","volume":"10","author":"Zhu","year":"2016","journal-title":"Drug Des. Devel Ther."}],"container-title":["Frontiers in Pharmacology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fphar.2021.718675\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,9,27]],"date-time":"2021-09-27T06:13:13Z","timestamp":1632723193000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fphar.2021.718675\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,9,27]]},"references-count":36,"alternative-id":["10.3389\/fphar.2021.718675"],"URL":"https:\/\/doi.org\/10.3389\/fphar.2021.718675","relation":{},"ISSN":["1663-9812"],"issn-type":[{"value":"1663-9812","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,9,27]]},"article-number":"718675"}}