{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:35:55Z","timestamp":1760060155309,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2025,8,1]],"date-time":"2025-08-01T00:00:00Z","timestamp":1754006400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia, Portugal","doi-asserted-by":"publisher","award":["UID\/MULTI\/04349\/2020"],"award-info":[{"award-number":["UID\/MULTI\/04349\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The use of radiosensitizers is a beneficial approach in cancer radiotherapy treatment. However, the enhancement of radiation effects on cancer cells by radiosensitizers involves several different mechanisms, reflecting the chemical nature of the radiosensitizer. G-quadruplex (G4) DNA ligands have emerged in recent years as a potential new class of radiosensitizers binding to specific DNA sequences. Recently, we have shown that the Re(I) tricarbonyl complex PDF-Pz-Re and its pyrazolyl-diamine chelator PDF-Pz, carrying a N-methylated pyridostatin (PDF) derivative, act as G4 binders of various G4-forming DNA and RNA sequences. As described in this contribution, these features prompted us to evaluate PDF-Pz-Re and PDF-Pz as radiosensitizers of prostate cancer PC3 cells submitted to concomitant treatment with Co-60 radiation. The compound RHPS4 was also tested, as this G4 ligand was previously shown to exhibit strong radiosensitizing properties in other cancer cell lines. The assessment of the resulting radiobiological effects, namely through clonogenic cell survival, DNA damage, and ROS production assays, showed that PDF-Pz-Re and PDF-Pz were able to radiosensitize PC3 cells despite being less active than RHPS4. Our results corroborate that G4 DNA ligands are a class of compounds with potential interest as radiosensitizers, deserving further studies to optimize their radiosensitization activity and elucidate the mechanisms of action.<\/jats:p>","DOI":"10.3390\/molecules30153240","type":"journal-article","created":{"date-parts":[[2025,8,4]],"date-time":"2025-08-04T13:11:11Z","timestamp":1754313071000},"page":"3240","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Evaluation of a Rhenium(I) Complex and Its Pyridostatin-Containing Chelator as Radiosensitizers for Chemoradiotherapy"],"prefix":"10.3390","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9164-0913","authenticated-orcid":false,"given":"Ant\u00f3nio","family":"Paulo","sequence":"first","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Campus Tecnol\u00f3gico e Nuclear, Estrada Nacional 10, Km 139.7, 2695-066 Bobadela LRS, Portugal"},{"name":"Departamento de Engenharia e Ci\u00eancias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Estrada Nacional 10, Km 139.7, 2695-066 Bobadela LRS, Portugal"}]},{"given":"Sofia","family":"Cardoso","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Campus Tecnol\u00f3gico e Nuclear, Estrada Nacional 10, Km 139.7, 2695-066 Bobadela LRS, Portugal"},{"name":"Departamento de F\u00edsica, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal"}]},{"given":"Edgar","family":"Mendes","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Campus Tecnol\u00f3gico e Nuclear, Estrada Nacional 10, Km 139.7, 2695-066 Bobadela LRS, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8877-6633","authenticated-orcid":false,"given":"Elisa","family":"Palma","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Campus Tecnol\u00f3gico e Nuclear, Estrada Nacional 10, Km 139.7, 2695-066 Bobadela LRS, Portugal"},{"name":"Departamento de Engenharia e Ci\u00eancias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Estrada Nacional 10, Km 139.7, 2695-066 Bobadela LRS, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9542-1427","authenticated-orcid":false,"given":"Paula","family":"Raposinho","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Campus Tecnol\u00f3gico e Nuclear, Estrada Nacional 10, Km 139.7, 2695-066 Bobadela LRS, Portugal"},{"name":"Departamento de Engenharia e Ci\u00eancias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Estrada Nacional 10, Km 139.7, 2695-066 Bobadela LRS, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6010-0316","authenticated-orcid":false,"given":"Ana","family":"Belchior","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Campus Tecnol\u00f3gico e Nuclear, Estrada Nacional 10, Km 139.7, 2695-066 Bobadela LRS, Portugal"},{"name":"Departamento de Engenharia e Ci\u00eancias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Estrada Nacional 10, Km 139.7, 2695-066 Bobadela LRS, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"i2","DOI":"10.1093\/jrr\/rrx092","article-title":"Selection of External Beam Radiotherapy Approaches for Precise and Accurate Cancer Treatment","volume":"59","author":"Shirato","year":"2018","journal-title":"J. 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