{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,7]],"date-time":"2025-11-07T09:41:54Z","timestamp":1762508514141,"version":"build-2065373602"},"reference-count":32,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2021,6,22]],"date-time":"2021-06-22T00:00:00Z","timestamp":1624320000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"DFG","doi-asserted-by":"publisher","award":["HE 1376\/38-1"],"award-info":[{"award-number":["HE 1376\/38-1"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ministry of Education, Science and Technological Developement of the Republic of Serbia","award":["451-03-68\/2020-14\/200007"],"award-info":[{"award-number":["451-03-68\/2020-14\/200007"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Gliomas and glioblastomas are very aggressive forms of brain tumors, prone to the development of a multitude of resistance mechanisms to therapeutic treatments, including cytoprotective autophagy. In this work, we investigated the role and mechanism of action of the combination of a ruthenacarborane derivative with 8-hydroxyquinoline (8-HQ), linked via an ester bond (complex 2), in rat astrocytoma C6 and human glioma U251 cells, in comparison with the two compounds alone, i.e., the free carboxylic acid (complex 1) and 8-HQ, and their non-covalent combination ([1 + 8-HQ], in 1:1 molar ratio). We found that only complex 2 was able to significantly affect cellular viability in glioma U251 cells (IC50 11.4 \u03bcM) via inhibition of the autophagic machinery, most likely acting at the early stages of the autophagic cascade. Contrary to 8-HQ alone, complex 2 was also able to impair cellular viability under conditions of glucose deprivation. We thus suggest different mechanisms of action of ruthenacarborane complex 2 than purely organic quinoline-based drugs, making complex 2 a very attractive candidate for evading the known resistances of brain tumors to chloroquine-based therapies.<\/jats:p>","DOI":"10.3390\/molecules26133801","type":"journal-article","created":{"date-parts":[[2021,6,22]],"date-time":"2021-06-22T22:10:59Z","timestamp":1624399859000},"page":"3801","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Ruthenacarborane and Quinoline: A Promising Combination for the Treatment of Brain Tumors"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8226-1623","authenticated-orcid":false,"given":"Dijana","family":"Dra\u010da","sequence":"first","affiliation":[{"name":"Department of Immunology, Institute for Biological Research \u201cSini\u0161a Stankovi\u0107\u201d, National Institute of Republic of Serbia, University of Belgrade, Bul. Despota Stefana 142, 11060 Belgrade, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Milan","family":"Markovi\u0107","sequence":"additional","affiliation":[{"name":"Department of Immunology, Institute for Biological Research \u201cSini\u0161a Stankovi\u0107\u201d, National Institute of Republic of Serbia, University of Belgrade, Bul. Despota Stefana 142, 11060 Belgrade, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marta","family":"Gozzi","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry and Mineralogy, Institute of Inorganic Chemistry, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany"},{"name":"Medical Faculty, Institute for Medical Physics and Biophysics, Leipzig University, H\u00e4rtelstr. 16\u201318, 04107 Leipzig, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sanja","family":"Mijatovi\u0107","sequence":"additional","affiliation":[{"name":"Department of Immunology, Institute for Biological Research \u201cSini\u0161a Stankovi\u0107\u201d, National Institute of Republic of Serbia, University of Belgrade, Bul. Despota Stefana 142, 11060 Belgrade, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8006-5079","authenticated-orcid":false,"given":"Danijela","family":"Maksimovi\u0107-Ivani\u0107","sequence":"additional","affiliation":[{"name":"Department of Immunology, Institute for Biological Research \u201cSini\u0161a Stankovi\u0107\u201d, National Institute of Republic of Serbia, University of Belgrade, Bul. Despota Stefana 142, 11060 Belgrade, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4267-0603","authenticated-orcid":false,"given":"Evamarie","family":"Hey-Hawkins","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry and Mineralogy, Institute of Inorganic Chemistry, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"111412","DOI":"10.1016\/j.jinorgbio.2021.111412","article-title":"Boron clusters as breast cancer therapeutics","volume":"218","author":"Murphy","year":"2021","journal-title":"J. Inorg. 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