{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,18]],"date-time":"2026-05-18T17:16:00Z","timestamp":1779124560667,"version":"3.51.4"},"reference-count":52,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2021,8,9]],"date-time":"2021-08-09T00:00:00Z","timestamp":1628467200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004663","name":"Ministry of Science and Technology, Taiwan","doi-asserted-by":"publisher","award":["MOST 105-2320-B-002-008-MY3; MOST 106-2312-B-002-003"],"award-info":[{"award-number":["MOST 105-2320-B-002-008-MY3; MOST 106-2312-B-002-003"]}],"id":[{"id":"10.13039\/501100004663","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:p>Glioblastoma is a malignant brain tumor with poor prognosis that rapidly acquires resistance to available clinical treatments. The herpes simplex virus thymidine kinase\/ganciclovir (HSVtk\/GCV) system produces the selective elimination of HSVtk-positive cells and is a candidate for preclinical testing against glioblastoma via its ability to regulate proliferation and differentiation. Therefore, in this study, we aimed to establish a plasmid encoding the HSVtk\/GCV system driven by a glial fibrillary acidic protein (GFAP) promoter and verify its possibility of neural differentiation of glioblastoma cell line under the GCV challenge. Four stable clones\u2014N2A-pCMV-HSVtk, N2A-pGFAP-HSVtk, U251-pCMV-HSVtk, and U251-pGFAP-HSVtk\u2014were established from neuronal N2A and glioblastoma U251 cell lines.<jats:italic>In vitro<\/jats:italic>GCV sensitivity was assessed by MTT assay for monitoring time- and dosage-dependent cytotoxicity. The capability for neural differentiation in stable glioblastoma clones during GCV treatment was assessed by performing immunocytochemistry for nestin, GFAP, and \u03b2III-tubulin. Under GFAP promoter control, the U251 stable clone exhibited GCV sensitivity, while the neuronal N2A clones were nonreactive. During GCV treatment, cells underwent apoptosis on day 3 and dying cells were identified after day 5. Nestin was increasingly expressed in surviving cells, indicating that the population of neural stem-like cells was enriched. Lower levels of GFAP expression were detected in surviving cells. Furthermore, \u03b2III-tubulin-positive neuron-like cells were identified after GCV treatment. This study established pGFAP-HSVtk-P2A-EGFP plasmids that successfully ablated GFAP-positive glioblastoma cells, but left neuronal N2A cells intact. These data suggest that the neural differentiation of glioblastoma cells can be promoted by treatment with the HSVtk\/GCV system.<\/jats:p>","DOI":"10.1371\/journal.pone.0253008","type":"journal-article","created":{"date-parts":[[2021,8,9]],"date-time":"2021-08-09T18:54:05Z","timestamp":1628535245000},"page":"e0253008","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":4,"title":["Neural differentiation of glioblastoma cell lines via a herpes simplex virus thymidine kinase\/ganciclovir system driven by a glial fibrillary acidic protein promoter"],"prefix":"10.1371","volume":"16","author":[{"given":"Elizabeth Wei-Chia","family":"Luo","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Meng-Lin","family":"Liao","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9806-486X","authenticated-orcid":true,"given":"Chung-Liang","family":"Chien","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2021,8,9]]},"reference":[{"issue":"4","key":"pone.0253008.ref001","doi-asserted-by":"crossref","first-page":"e273","DOI":"10.3747\/co.22.2436","article-title":"Nonsurgical treatment of recurrent glioblastoma","volume":"22","author":"O Gallego","year":"2015","journal-title":"Current oncology (Toronto, Ont)"},{"issue":"1","key":"pone.0253008.ref002","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1007\/s11060-011-0793-0","article-title":"Recent advances in the molecular understanding of glioblastoma","volume":"108","author":"FE Bleeker","year":"2012","journal-title":"Journal of neuro-oncology"},{"issue":"6","key":"pone.0253008.ref003","doi-asserted-by":"crossref","first-page":"1111","DOI":"10.1016\/j.cell.2006.03.011","article-title":"Stem cells and cancer: two faces of eve","volume":"124","author":"MF Clarke","year":"2006","journal-title":"Cell"},{"issue":"12","key":"pone.0253008.ref004","doi-asserted-by":"crossref","first-page":"1203","DOI":"10.1038\/labinvest.3700488","article-title":"The cancer stem cell hypothesis: a work in progress","volume":"86","author":"BT Tan","year":"2006","journal-title":"Laboratory investigation; a journal of technical methods and pathology"},{"issue":"18","key":"pone.0253008.ref005","doi-asserted-by":"crossref","first-page":"3015","DOI":"10.1200\/JCO.2007.15.7164","article-title":"Stem cell-related \"self-renewal\" signature and high epidermal growth factor receptor expression associated with resistance to concomitant chemoradiotherapy in glioblastoma","volume":"26","author":"A Murat","year":"2008","journal-title":"Journal of clinical oncology: official journal of the American Society of Clinical Oncology"},{"key":"pone.0253008.ref006","first-page":"267","volume":"58","author":"P Dalerba","year":"2007","journal-title":"Cancer stem cells: models and concepts. 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