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<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">OL</journal-id>
<journal-title-group>
<journal-title>Oncology Letters</journal-title>
</journal-title-group>
<issn pub-type="ppub">1792-1074</issn>
<issn pub-type="epub">1792-1082</issn>
<publisher>
<publisher-name>D.A. Spandidos</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.3892/ol.2026.15645</article-id>
<article-id pub-id-type="publisher-id">OL-32-1-15645</article-id>
<article-categories>
<subj-group>
<subject>Expression of Concern</subject>
</subj-group>
</article-categories>
<title-group>
<article-title>[Expression of Concern] Rap2B promotes the proliferation and migration of human glioma cells via activation of the ERK pathway</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author"><name><surname>Shi</surname><given-names>Guohong</given-names></name>
</contrib>
<contrib contrib-type="author"><name><surname>Zhang</surname><given-names>Zhen</given-names></name>
</contrib>
</contrib-group>
<pub-date pub-type="collection"><month>07</month><year>2026</year></pub-date>
<pub-date pub-type="epub"><day>11</day><month>05</month><year>2026</year></pub-date>
<volume>32</volume>
<issue>1</issue>
<elocation-id>290</elocation-id>
<permissions>
<copyright-statement>Copyright: &#x00A9; 2026 Shi and Zhang.</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>
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<body>
<p>Oncol Lett 21: <related-article xmlns:xlink="http://www.w3.org/1999/xlink" related-article-type="object-of-concern" vol="21" page="314" id="RA1" xlink:href="10.3892/ol.2021.12575" ext-link-type="doi">314</related-article>, 2021; DOI: 10.3892/ol.2021.12575</p>
<p>Following the publication of the above paper, it has been drawn to the Editor&#x0027;s attention by a concerned reader that, regarding the Transwell invasion assay data shown in Fig. 3A on p. 6, the Control and si-Rap2B data panels contained an overlapping section, suggesting that these data panels, which were intended to show the results of differently performed experiments, had been derived from the same original source. A subsequent analysis of the data in this paper undertaken by the Editorial Office revealed that the Control data panels comparing Fig. 3A with 3B also contained an overlapping section.</p>
<p>The authors have been contacted by the Editorial Office to offer an explanation for these apparent anomalies in the presentation of the data in this paper, and we are awaiting their response. Owing to the fact that the Editorial Office has been made aware of potential issues surrounding the scientific integrity of this paper, we are issuing an Expression of Concern to notify readers of this potential problem while the Editorial Office continues to investigate this matter further.</p>
</body>
</article>
