{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,12]],"date-time":"2026-02-12T10:47:26Z","timestamp":1770893246564,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2022,10,13]],"date-time":"2022-10-13T00:00:00Z","timestamp":1665619200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FEDER\u2014Fundo Europeu de Desenvolimento Regional through the COMPETE 2020\u2014Operational Programme for Competitiveness and Internationalization (POCI), Portugal 2020","award":["UIDB\/4255\/2020"],"award-info":[{"award-number":["UIDB\/4255\/2020"]}]},{"name":"FEDER\u2014Fundo Europeu de Desenvolimento Regional through the COMPETE 2020\u2014Operational Programme for Competitiveness and Internationalization (POCI), Portugal 2020","award":["IF\/00092\/2014\/CP1255\/CT0004"],"award-info":[{"award-number":["IF\/00092\/2014\/CP1255\/CT0004"]}]},{"name":"the project RISE\u2014LA\/P\/0053\/2020. N.V. is also thankful for the support from FCT and FEDER (European Union)","award":["UIDB\/4255\/2020"],"award-info":[{"award-number":["UIDB\/4255\/2020"]}]},{"name":"the project RISE\u2014LA\/P\/0053\/2020. N.V. is also thankful for the support from FCT and FEDER (European Union)","award":["IF\/00092\/2014\/CP1255\/CT0004"],"award-info":[{"award-number":["IF\/00092\/2014\/CP1255\/CT0004"]}]},{"name":"CHAIR in Onco-Innovation at FMUP","award":["UIDB\/4255\/2020"],"award-info":[{"award-number":["UIDB\/4255\/2020"]}]},{"name":"CHAIR in Onco-Innovation at FMUP","award":["IF\/00092\/2014\/CP1255\/CT0004"],"award-info":[{"award-number":["IF\/00092\/2014\/CP1255\/CT0004"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Prostate and lung cancers are among the most common cancer types, and they still need more therapeutics. For this purpose, saquinavir (SAQ) was tested alone and in combination with 5-fluorouracil (5-FU). PC-3 and A549 cells were exposed to increasing concentrations of both drugs alone or in combination, with simultaneous or sequential administration. Cell viability was obtained using the MTT assay and synergism values using CompuSyn software. Results showed that SAQ was the more cytotoxic of both drugs in PC-3 cells, while 5-FU was the most cytotoxic in A549 cells. When these drugs were used in combination, the more synergistic combination in PC-3 cells was the IC50 of SAQ with various concentrations of 5-FU, particularly when 5-FU was only applied 24 h later. Meanwhile for A549 the most promising combination was 5-FU with delayed SAQ, but with a weaker effect than all combinations demonstrated in PC-3 cells. These results demonstrate that SAQ could be used as a new repurposed drug for the treatment of prostate cancer and this treatment potential could be even greater if SAQ is combined with the anticancer drug 5-FU, while for lung cancer it is not as efficient and, therefore, not of as much interest.<\/jats:p>","DOI":"10.3390\/ijms232012240","type":"journal-article","created":{"date-parts":[[2022,10,13]],"date-time":"2022-10-13T22:21:11Z","timestamp":1665699671000},"page":"12240","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Repurposing Alone and in Combination of the Antiviral Saquinavir with 5-Fluorouracil in Prostate and Lung Cancer Cells"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8202-1459","authenticated-orcid":false,"given":"Mariana","family":"Pereira","sequence":"first","affiliation":[{"name":"OncoPharma Research Group, Center for Health Technology and Services Research (CINTESIS), Rua Doutor Pl\u00e1cido da Costa, s\/n, 4200-450 Porto, Portugal"},{"name":"Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"},{"name":"CINTESIS@RISE, Faculty of Medicine, University of Porto, Alameda Professor Hern\u00e2ni Monteiro, 4200-319 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1283-1042","authenticated-orcid":false,"given":"Nuno","family":"Vale","sequence":"additional","affiliation":[{"name":"OncoPharma Research Group, Center for Health Technology and Services Research (CINTESIS), Rua Doutor Pl\u00e1cido da Costa, s\/n, 4200-450 Porto, Portugal"},{"name":"CINTESIS@RISE, Faculty of Medicine, University of Porto, Alameda Professor Hern\u00e2ni Monteiro, 4200-319 Porto, Portugal"},{"name":"Department of Community Medicine, Information and Health Decision Sciences (MEDCIDS), Faculty of Medicine, University of Porto, Rua Doutor Pl\u00e1cido da Costa, s\/n, 4200-450 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,13]]},"reference":[{"key":"ref_1","unstructured":"Cancer.Net (2022, June 28). 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