{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T02:37:53Z","timestamp":1774319873150,"version":"3.50.1"},"reference-count":22,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2016,1,13]],"date-time":"2016-01-13T00:00:00Z","timestamp":1452643200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Our previous work has described a library of thioxanthones designed to have dual activity as P-glycoprotein modulators and antitumor agents. Some of these compounds had shown a significant cell growth inhibitory activity towards leukemia cell lines, without affecting the growth of non-tumor human fibroblasts. However, their effect in cell lines derived from solid tumors has not been previously studied. The present work aimed at: (i) screening this small series of compounds from an in-house library, for their in vitro cell growth inhibitory activity in human tumor cell lines derived from solid tumors; and (ii) initiate a study of the effect of the most potent compound on apoptosis. The tumor cell growth inhibitory effect of 27 compounds was first analysed in different human tumor cell lines, allowing the identification of a hit compound, TXA1. Its hydrochloride salt TXA1\u00b7HCl was then synthesized, to improve solubility and bioavailability. Both TXA1 and TXA1\u00b7HCl inhibited the growth of MCF-7, NCI-H460, A375-C5, HeLa, 786-O, Caki-2 and AGS cell lines. The effect of TXA1\u00b7HCl in MCF-7 cells was found to be irreversible and was associated, at least in part, with an increase in cellular apoptosis.<\/jats:p>","DOI":"10.3390\/molecules21010081","type":"journal-article","created":{"date-parts":[[2016,1,13]],"date-time":"2016-01-13T22:19:54Z","timestamp":1452723594000},"page":"81","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Screening a Small Library of Xanthones for Antitumor Activity and Identification of a Hit Compound which Induces Apoptosis"],"prefix":"10.3390","volume":"21","author":[{"given":"Jo\u00e3o","family":"Barbosa","sequence":"first","affiliation":[{"name":"CESPU, Instituto de Investiga\u00e7\u00e3o e Forma\u00e7\u00e3o Avan\u00e7ada em Ci\u00eancias e Tecnologias da Sa\u00fade, IUCS\u2014Instituto Universit\u00e1rio de Ci\u00eancias da Sa\u00fade, Rua Central de Gandra 1317, Gandra 4585-116, Portugal"}]},{"given":"Raquel","family":"Lima","sequence":"additional","affiliation":[{"name":"i3S\u2014Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade da Universidade do Porto, Rua Alfredo Allen 208, Porto 4200-135, Portugal"},{"name":"Cancer Drug Resistance Group, IPATIMUP\u2014Institute of Molecular Pathology and Immunology of the University of Porto, Porto 4200-135, Portugal"},{"name":"Department of Pathology and Oncology, FMUP\u2014Faculty of Medicine of the University of Porto, Alameda Prof. Hern\u00e2ni Monteiro, Porto 4200-319, Portugal"}]},{"given":"Diana","family":"Sousa","sequence":"additional","affiliation":[{"name":"i3S\u2014Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade da Universidade do Porto, Rua Alfredo Allen 208, Porto 4200-135, Portugal"},{"name":"Cancer Drug Resistance Group, IPATIMUP\u2014Institute of Molecular Pathology and Immunology of the University of Porto, Porto 4200-135, Portugal"},{"name":"Laboratory of Microbiology, Department of Biological Sciences, FFUP\u2014Faculty of Pharmacy of the University of Porto, Rua de Jorge Viterbo Ferreira 228, Porto 4050-313, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9378-6043","authenticated-orcid":false,"given":"Ana","family":"Gomes","sequence":"additional","affiliation":[{"name":"Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, FFUP\u2014Faculty of Pharmacy of the University of Porto, Rua de Jorge Viterbo Ferreira 228, Porto 4050-313, Portugal"},{"name":"UCIBIO\/REQUIMTE, Laborat\u00f3rio de Microbiologia, Departamento de Ci\u00eancias Biol\u00f3gicas, Faculdade de Farm\u00e1cia, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, Porto 4050-313, Portugal"}]},{"given":"Andreia","family":"Palmeira","sequence":"additional","affiliation":[{"name":"Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, FFUP\u2014Faculty of Pharmacy of the University of Porto, Rua de Jorge Viterbo Ferreira 228, Porto 4050-313, Portugal"}]},{"given":"Hugo","family":"Seca","sequence":"additional","affiliation":[{"name":"i3S\u2014Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade da Universidade do Porto, Rua Alfredo Allen 208, Porto 4200-135, Portugal"},{"name":"Cancer Drug Resistance Group, IPATIMUP\u2014Institute of Molecular Pathology and Immunology of the University of Porto, Porto 4200-135, Portugal"}]},{"given":"Kantima","family":"Choosang","sequence":"additional","affiliation":[{"name":"Faculty of Medicinal Technology, Rangsit University, 52\/347 Muang Ake, Phaholyothin Road, Lakhok, Pathumthani 10210, Thailand"}]},{"given":"Pannee","family":"Pakkong","sequence":"additional","affiliation":[{"name":"Applied Radiation and Isotopes Department, Faculty of Science, Kasetsart University, Jatujak, Bangkok 10930, Thailand"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4006-5779","authenticated-orcid":false,"given":"Hassan","family":"Bousbaa","sequence":"additional","affiliation":[{"name":"CESPU, Instituto de Investiga\u00e7\u00e3o e Forma\u00e7\u00e3o Avan\u00e7ada em Ci\u00eancias e Tecnologias da Sa\u00fade, IUCS\u2014Instituto Universit\u00e1rio de Ci\u00eancias da Sa\u00fade, Rua Central de Gandra 1317, Gandra 4585-116, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4676-1409","authenticated-orcid":false,"given":"Madalena","family":"Pinto","sequence":"additional","affiliation":[{"name":"Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, FFUP\u2014Faculty of Pharmacy of the University of Porto, Rua de Jorge Viterbo Ferreira 228, Porto 4050-313, Portugal"},{"name":"CIIMAR\/CIMAR\u2014Centro Interdisciplinar de Investiga\u00e7\u00e3o Marinha e Ambiental, Universidade do Porto, Rua dos Bragas 289, Porto 4050-123, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5397-4672","authenticated-orcid":false,"given":"Em\u00edlia","family":"Sousa","sequence":"additional","affiliation":[{"name":"Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, FFUP\u2014Faculty of Pharmacy of the University of Porto, Rua de Jorge Viterbo Ferreira 228, Porto 4050-313, Portugal"},{"name":"CIIMAR\/CIMAR\u2014Centro Interdisciplinar de Investiga\u00e7\u00e3o Marinha e Ambiental, Universidade do Porto, Rua dos Bragas 289, Porto 4050-123, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7801-4643","authenticated-orcid":false,"given":"M.","family":"Vasconcelos","sequence":"additional","affiliation":[{"name":"i3S\u2014Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade da Universidade do Porto, Rua Alfredo Allen 208, Porto 4200-135, Portugal"},{"name":"Cancer Drug Resistance Group, IPATIMUP\u2014Institute of Molecular Pathology and Immunology of the University of Porto, Porto 4200-135, Portugal"},{"name":"Laboratory of Microbiology, Department of Biological Sciences, FFUP\u2014Faculty of Pharmacy of the University of Porto, Rua de Jorge Viterbo Ferreira 228, Porto 4050-313, Portugal"}]},{"given":"Madalena","family":"Pedro","sequence":"additional","affiliation":[{"name":"CESPU, Instituto de Investiga\u00e7\u00e3o e Forma\u00e7\u00e3o Avan\u00e7ada em Ci\u00eancias e Tecnologias da Sa\u00fade, IUCS\u2014Instituto Universit\u00e1rio de Ci\u00eancias da Sa\u00fade, Rua Central de Gandra 1317, Gandra 4585-116, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2016,1,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1111\/j.1476-5381.1948.tb00370.x","article-title":"Miracil D, its toxicology, absorption, and excretion in animals and human volunteers","volume":"3","author":"Hawking","year":"1948","journal-title":"Br. 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