[Retracted] MicroRNA‑454 inhibits tumor cell proliferation, migration and invasion by downregulating zinc finger E‑box‑binding homeobox 1 in gastric cancer

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that certain of the cell migration assay data shown in Fig. 3A and B and Fig. 5D were strikingly similar to data that had appeared in different form in other articles by different authors (in addition to the apparent duplication of some of these data within this paper itself). Owing to the fact that the contentious data in the above article had already been published elsewhere, or were already under consideration for publication, prior to its submission to Molecular Medicine Reports, the Editor has decided that this paper should be retracted from the Journal. 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. [Molecular Medicine Reports 16: 9067‑9073, 2017; DOI: 10.3892/mmr.2017.7758].

Knockdown of ZEB1 reverses cancer stem cell properties in prostate cancer cells

Prostate cancer (PCa) is the second most diagnosed type of cancer in men worldwide. Advanced PCa is resistant to conventional therapies and high recurrence has been associated with high rates of metastasis. Cancer stem cells (CSCs) have been proposed to be responsible for this, due to their ability of self‑renewal and differentiation into other cell types. Zinc finger E‑box‑binding homeobox 1 (ZEB1), a transcription factor involved in the regulation of epithelial‑mesenchymal transition (EMT), has been associated with the activation of several mechanisms that lead to resistance to treatment. As recent evidence has shown that CSCs may originate from non‑CSCs during EMT, it was hypothesized that knocking down ZEB1 expression in PCa cell lines could revert some properties associated with CSCs. Using lentiviraltransduction, ZEB1 expression was silenced in the PCa DU145 and LNCaP cell lines. The mRNA and protein expression levels of key canonical CSC markers (Krüppel‑like factor 4, SOX2, CD44 and CD133) were determined using reverse transcription‑-quantitative PCR and western blot analysis, respectively. In addition, the colony forming ability of the ZEB1‑knockdown cells was evaluated, and the type of colonies formed (holoclones, paraclones and meroclones) was also characterized. Finally, the ability to form prostatospheres was evaluated in vitro. It was found that in ZEB1‑knockdown DU145 cells, the expression levels of CSC phenotype markers (CD44, CD133 and SOX2) were decreased compared with those in the control group. Furthermore, ZEB1‑knockdown cells exhibited a lower ability to form prostatospheres and to generate colonies. In conclusion, stable silencing of ZEB1 reversed CSC properties in PCa cell lines. Since ZEB1 is associated with malignancy, therapy resistance and a CSC phenotype in PCa cell lines, targeting ZEB1 may be a key factor to eradicate CSCs and improve the prognosis of patients with advanced PCa.