{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:12:05Z","timestamp":1792789925314,"version":"4.5.0"},"reference-count":30,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,20]],"date-time":"2026-09-20T00:00:00Z","timestamp":1789862400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Istanbul Atlas University","id":[{"id":"https:\/\/ror.org\/02jqzm779","id-type":"ROR","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/02jqzm779","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Background: Glioblastoma (GBM) remains difficult to treat, and natural bioactive formulations are being explored as experimental modifiers of tumor-associated cellular processes. This study examined a fixed-ratio olive polyphenol\u2013bromelain formulation in U87MG cells and performed targeted phenolic characterization of its olive-derived component. Methods: Seven phenolics were quantified by LC\u2013MS\/MS. U87MG cells were exposed to the formulation or a bromelain comparator. The MTT metabolic signal, DNA-content cell-cycle distribution, IL-6, IL-10, and extracellular total antioxidant capacity (TAC) were assessed. Results: The total quantified phenolics were 483.22 mg\/kg, with oleocanthal, oleuropein, and 3,4-DHPEA-EDA predominating. The formulation reduced the MTT signal more than bromelain at lower and intermediate concentrations, although the response became non-monotonic at higher concentrations. Combination-treated cells showed greater G0\/G1 accumulation. Culture supernatants showed lower IL-6 and higher IL-10 and TAC relative to untreated controls. Conclusions: The formulation was associated with changes in metabolic activity, cell-cycle distribution, and extracellular cytokine\/redox readouts in U87MG cells. Because no polyphenol-only arm, direct cell-death assay, complete replicate-level inferential analysis, or non-tumoral comparator was available, the findings are descriptive and do not establish synergy, cytotoxicity, mechanism, tumor selectivity, or therapeutic efficacy.<\/jats:p>","DOI":"10.3390\/molecules31183334","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T14:12:09Z","timestamp":1789999929000},"page":"3334","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["In Vitro Effects of an Olive Polyphenol\u2013Bromelain Formulation on U87MG Glioblastoma Cells: Viability, Cell-Cycle Distribution, Cytokine Release, and Total Antioxidant Capacity"],"prefix":"10.3390","volume":"31","author":[{"given":"Enver","family":"Ciraci","sequence":"first","affiliation":[{"name":"Department of Biochemistry, Faculty of Pharmacy, Biruni University, Zeytinburnu, 34010 Istanbul, T\u00fcrkiye"},{"name":"Biruni Advanced Technology Application and Research Center (BAMER), Biruni University, 34015 Istanbul, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1311-6892","authenticated-orcid":false,"given":"Tugba","family":"Elgun","sequence":"additional","affiliation":[{"name":"Biruni Advanced Technology Application and Research Center (BAMER), Biruni University, 34015 Istanbul, T\u00fcrkiye"},{"name":"Department of Medical Biology, Faculty of Medicine, Biruni University, Zeytinburnu, 34015 Istanbul, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"}]},{"given":"Yasemin Musteri","family":"Oltulu","sequence":"additional","affiliation":[{"name":"Biruni Advanced Technology Application and Research Center (BAMER), Biruni University, 34015 Istanbul, T\u00fcrkiye"},{"name":"Department of Medical Biology, Faculty of Medicine, Biruni University, Zeytinburnu, 34015 Istanbul, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-4172-4748","authenticated-orcid":false,"given":"Halil Ibrahim","family":"Arslan","sequence":"additional","affiliation":[{"name":"Biruni Advanced Technology Application and Research Center (BAMER), Biruni University, 34015 Istanbul, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6424-7411","authenticated-orcid":false,"given":"Asiye Gok","family":"Yurttas","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Faculty of Medicine, Istanbul Atlas University, 34408 Istanbul, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9438-6113","authenticated-orcid":false,"given":"Gul Ipek","family":"Gundogan","sequence":"additional","affiliation":[{"name":"Biruni Advanced Technology Application and Research Center (BAMER), Biruni University, 34015 Istanbul, T\u00fcrkiye"},{"name":"Department of Histology and Embryology, Faculty of Medicine, Biruni University, 34015 Istanbul, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lokman","family":"Uzun","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Faculty of Science, Hacettepe University, 06800 Ankara, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"visualization","vocabulary":"credit"},{"role":"conceptualization","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Gurol","family":"Emekdas","sequence":"additional","affiliation":[{"name":"Turk Kan Vakfi, 34718 Istanbul, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1231","DOI":"10.1093\/neuonc\/noab106","article-title":"The 2021 WHO Classification of Tumors of the Central Nervous System: 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