The Editors of JBUON issue an Expression of Concern to 'Antitumor effects of flavokawain-B flavonoid in gemcitabine resistant lung cancer cells are mediated via mitochondrial mediated apoptosis, ROS production, cell migration and cell invasion inhibition and blocking of PI3K/AKT Signaling pathway', by Rong Hua, Yaofei Pei, Haiyong Gu, Yifeng Sun, Yi He, JBUON 2020;25(1):262-267; PMID: 32277640. Following the publication of the above article, readers drew to our attention that part of the data was possibly unreliable. We sent emails to the authors with a request to provide the raw data to prove the originality, but received no reply. Therefore, as we continue to work through the issues raised, we advise readers to interpret the information presented in the article with due caution. We thank the readers for bringing this matter to our attention. We apologize for any inconvenience it may cause.