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<front>
<journal-meta>
<journal-id journal-id-type="nlm-ta">OR</journal-id>
<journal-title-group>
<journal-title>Oncology Reports</journal-title>
</journal-title-group>
<issn pub-type="ppub">1021-335X</issn>
<issn pub-type="epub">1791-2431</issn>
<publisher>
<publisher-name>D.A. Spandidos</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.3892/or.2026.9160</article-id>
<article-id pub-id-type="publisher-id">OR-56-3-09160</article-id>
<article-categories>
<subj-group>
<subject>Retraction</subject>
</subj-group>
</article-categories>
<title-group>
<article-title>[Retracted] Synergistic cytotoxic effects of inorganic phosphate and chemotherapeutic drugs on human osteosarcoma cells</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author"><name><surname>Spina</surname><given-names>Annamaria</given-names></name>
</contrib>
<contrib contrib-type="author"><name><surname>Sorvillo</surname><given-names>Luca</given-names></name>
</contrib>
<contrib contrib-type="author"><name><surname>Chiosi</surname><given-names>Emilio</given-names></name>
</contrib>
<contrib contrib-type="author"><name><surname>Esposito</surname><given-names>Antonietta</given-names></name>
</contrib>
<contrib contrib-type="author"><name><surname>Di Maiolo</surname><given-names>Francesca</given-names></name>
</contrib>
<contrib contrib-type="author"><name><surname>Sapio</surname><given-names>Luigi</given-names></name>
</contrib>
<contrib contrib-type="author"><name><surname>Caraglia</surname><given-names>Michele</given-names></name>
</contrib>
<contrib contrib-type="author"><name><surname>Naviglio</surname><given-names>Silvio</given-names></name>
</contrib>
</contrib-group>
<pub-date pub-type="collection"><month>09</month><year>2026</year></pub-date>
<pub-date pub-type="epub"><day>06</day><month>07</month><year>2026</year></pub-date>
<volume>56</volume>
<issue>3</issue>
<elocation-id>155</elocation-id>
<permissions>
<copyright-statement>Copyright: &#x00A9; 2026 Spina et al.</copyright-statement>
<copyright-year>2026</copyright-year>
<license license-type="open-access">
<license-p>This is an open access article distributed under the terms of the <ext-link ext-link-type="uri" xlink:href="https://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution License</ext-link>, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ) and either DOI or URL of the article must be cited.</license-p></license>
</permissions>
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</front>
<body>
<p>Oncol Rep 29: <related-article xmlns:xlink="http://www.w3.org/1999/xlink" related-article-type="retracted-article" vol="29" page="1689" id="RA1" xlink:href="10.3892/or.2013.2306" ext-link-type="doi">1689&#x2013;1696</related-article>, 2013; DOI: 10.3892/or.2013.2306</p>
<p>Subsequently to the publication of the above article, a concerned reader drew the Editor&#x0027;s attention to the fact that, regarding the western blots shown in Fig. 3B on p. 1692, the tubulin bands shown for lanes 4 and 5 (showing the &#x2018;Doxo&#x002B;Pi&#x2019; and &#x2018;Taxol&#x2019; experiments) were strikingly similar to the tubulin blots shown for lanes 7 and 8 (showing the &#x2018;5-FU&#x2019; and &#x2018;5-FU&#x002B;Pi&#x2019; experiments), suggesting possible inappropriate editing of this figure in the paper. It also came to light that the data in question reappeared in a paper published subsequently by the same research group in the journal <italic>Molecules</italic> a couple of years afterwards. Having assessed these data independently in the Editorial Office, the concerns raised by the reader were judged to have been well founded; therefore, the Editor of <italic>Oncology Reports</italic> has decided that the paper should be retracted from the Journal on account of a lack of confidence in the presented data. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor apologizes to the readership for any inconvenience caused.</p>
</body>
</article>
