{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T05:11:35Z","timestamp":1789708295892,"version":"4.0.1"},"reference-count":48,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T00:00:00Z","timestamp":1782950400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002657","name":"Istanbul University Scientific Research Projects Coordination Unit","doi-asserted-by":"publisher","award":["TDP-2020-36598"],"award-info":[{"award-number":["TDP-2020-36598"]}],"id":[{"id":"10.13039\/501100002657","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002657","name":"Istanbul University Scientific Research Projects Coordination Unit","doi-asserted-by":"publisher","award":["TSA-2023-39461"],"award-info":[{"award-number":["TSA-2023-39461"]}],"id":[{"id":"10.13039\/501100002657","id-type":"DOI","asserted-by":"publisher"}]},{"award":["TDP-2020-36598"],"award-info":[{"award-number":["TDP-2020-36598"]}],"id":[{"id":"https:\/\/ror.org\/03a5qrr21","id-type":"ROR","asserted-by":"publisher"}]},{"award":["TSA-2023-39461"],"award-info":[{"award-number":["TSA-2023-39461"]}],"id":[{"id":"https:\/\/ror.org\/03a5qrr21","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Achieving optimal therapeutic efficacy in colorectal cancer (CRC) remains challenging, highlighting the need for novel treatment strategies. This study evaluated whether radiofrequency (RF) hyperthermia enhances the anticancer effects of sunitinib malate and a newly synthesized tyrosine kinase (TK) inhibitor (compound 4). HCT116 CRC cells and BEAS-2B normal epithelial cells were treated with increasing concentrations of both agents in the presence or absence of RF exposure using a mobile RF device. Cell viability and death were assessed by MTT assay and flow cytometry (Annexin V\/PI). RF exposure was associated with reduced viability and increased cell death in HCT116 cells (p &lt; 0.05). Flow cytometric analysis confirmed that RF exposure may contribute to the observed reduction in viability. Notably, the findings suggest a possible beneficial contribution of RF hyperthermia to the observed cytotoxic effects, particularly near the IC50 concentration. In contrast, BEAS-2B cells maintained high viability with no significant changes (p &gt; 0.05). These findings suggest that RF exposure may contribute to the observed cytotoxic responses in CRC cells while exerting limited effects on non-malignant cells, suggesting a promising strategy for targeted therapy.<\/jats:p>","DOI":"10.3390\/ijms27135953","type":"journal-article","created":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T14:51:25Z","timestamp":1783003885000},"page":"5953","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["The Effect of Radiofrequency Exposure on the Cytotoxic Activity of Sunitinib and a Novel Sunitinib-Class Compound 4, in Colorectal Cancer Cells"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4454-4651","authenticated-orcid":false,"given":"Ayse","family":"Erol Bozkurt","sequence":"first","affiliation":[{"name":"Department of Medical Biology, Istanbul Faculty of Medicine, Istanbul University, 34093 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1401-4863","authenticated-orcid":false,"given":"Mediha","family":"Suleymanoglu","sequence":"additional","affiliation":[{"name":"Department of Medical Biology, Istanbul Faculty of Medicine, Istanbul University, 34093 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tugce","family":"Cinek","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Istanbul Health and Technology University, 34275 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nilgun","family":"Karali","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Istanbul University, 34116 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sedat","family":"Ballikaya","sequence":"additional","affiliation":[{"name":"Department of Engineering Sciences, Faculty of Engineering, Istanbul University\u2013Cerrahpa\u015fa, 34320 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mehmet Salih","family":"Iyikesici","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, School of Medicine, Altinbas University, 34147 Istanbul, Turkey"},{"name":"ChemoThermia Oncology Center, 34295 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7878-9994","authenticated-orcid":false,"given":"Serap","family":"Kuruca","sequence":"additional","affiliation":[{"name":"Department of Physiology, Faculty of Medicine, Istanbul Atlas University, 34408 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"338","DOI":"10.1136\/gutjnl-2022-327736","article-title":"Global burden of colorectal cancer in 2020 and 2040: Incidence and mortality estimates from GLOBOCAN","volume":"72","author":"Morgan","year":"2023","journal-title":"Gut"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"59","DOI":"10.5604\/01.3001.0055.0608","article-title":"Colorectal cancer: Application of selected liquid biopsy markers","volume":"97","author":"Skrzypek","year":"2025","journal-title":"Pol. 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