Retracted : Long noncoding RNA MEG3 inhibits proliferation and migration but induces autophagy by regulation of Sirt7 and PI3K/AKT/mTOR pathway in glioma cells
Authors: Dong-Yuan Li
Dong-Hui Xu
Cong-Hai Zhao
Guo-Nan Chi
Journal: Journal of Cellular Biochemistry (2018)
Discipline: MOLECULAR BIOLOGY & GENETICS
Keywords: MEG3; PI3K/AKT/mTOR; Sirt7; autophagy; glioma
Affiliations: Department of Neurosurgery, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China.

Abstract:  Glioma is a common primary brain tumor with high mortality rate and poor prognosis. Long noncoding RNA maternally expressed gene 3 (MEG3) is a tumor suppressor in diverse cancer types. However, the role of MEG3 in glioma remains unclear. We aimed to explore the effects of MEG3 on U251 cells as well as the underlying mechanisms. U251 cells were stably transfected with different recombined plasmids to overexpress or silence MEG3. Effects of aberrantly expressed MEG3 on cell viability, migration, apoptosis, expressions of apoptosis-associated and autophagy-associated proteins, and phosphorylated levels of key kinases in the PI3K/AKT/mTOR pathway were all evaluated. Then, messenger RNA (mRNA) and protein expression of Sirt7 in cells abnormally expressing MEG3 were estimated. In addition, effects of abnormally expressed MEG3 and Sirt7 on U251 cells were determined to reveal the underlying mechanism of MEG3-associated modulation. Cell viability and migration were significantly reduced by MEG3 overexpression whereas cell apoptosis as well as Bax and cleaved caspase-3/-9 proteins were obviously induced. Beclin-1 and LC3-II/LC3-I were upregulated and p62 was downregulated in MEG3 overexpressed cells. In addition, the autophagy pharmacological inhibitor (3-methyladenine, 3-MA) affected the effect of MEG3 overexpression on cell proliferation. Furthermore, the phosphorylated levels of key kinases in the PI3K/AKT/mTOR pathway were all reduced by MEG3 overexpression. Sirt7 was positively regulated by MEG3 expression, and effects of MEG3 overexpression on U251 cells were ameliorated by Sirt7 silence. MEG3 suppressed cell proliferation and migration but promoted autophagy in U251 cells through positively regulating Sirt7, involving in the inhibition of the PI3K/AKT/mTOR pathway. 

Retracted: Yes

PubPeer comments:
 The Western blots and other figures in this paper have an interesting layout that appears to be shared with many other papers, as discussed in a January 2020 post on Leonid Schneider s blog: https: forbetterscience.com 2020 01 24 the-full-service-paper-mill-and-its-chinese-customers The list of these papers is available here: https: docs.google.com spreadsheets d 1KXqTAyl4j-jVorFPMD2XRpr76LcIKJ0CVyIvRj0exYQ edit?usp=sharing In almost all papers, Western blot panels within the same figure, and across figures and papers, appear to share the same background, while the bands are regularly spaced, all have similar rounded edges without the usual smudges and specks, and with some bands showing a recognizable  jumping sardine shape. Also in almost all papers, bar graphs show a characteristic layout with bars in solid shades of grey, and the left-most bar in black, as well as double-edged error bars. Many papers have  cell viability and  apoptotic cells graphs. To illustrate the recognizable layout of the graphs in this paper, here is Figure 2. ![file] , 
 Retracted [8 June 2021] . -------------------------------------------------- The above article, published online on 11 November 2018 in Wiley Online Library , has been retracted by agreement between the the journal s Editor in Chief, Prof. Dr. Christian Behl, and Wiley Periodicals LLC. The retraction has been agreed following an investigation based on allegations raised by a third party. Several flaws and inconsistencies between results presented and experimental methods described were found, the editors consider the conclusions of this article to be invalid. The authors collaborated in the investigation initially, but were not available for a final confirmation of the retraction. ,