MicroRNA-22 inhibits cell growth and metastasis in breast cancer via targeting of SIRT1
Authors: Xiaofeng Dong
Xuedi Wang
Dong Huang
Zhongxiao Liang
Quanqing Zou
Yinhua Pan
Qianli Tang
Journal: Experimental and Therapeutic Medicine (2017)
Discipline: CLINICAL MEDICINE
Keywords: Sirtuin1; breast cancer; growth; metastasis; microRNA-22.
Affiliations: Department of Breast Surgery, First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510632, P.R. China., Department of Hepatobiliary and Endocrine Surgery, People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, Guangxi 530021, P.R. China., Department of General Surgery, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi 533000, P.R. China.

Abstract:  MicroRNAs (miRs), which are a class of small non-coding RNAs, are key regulators of gene expression via induction of translational repression or mRNA degradation. However, the molecular mechanism of miR-22 underlying the malignant progression of breast cancer, remains to be elucidated. The present study aimed to explore the regulatory mechanism of miR-22 in breast cancer cell growth and metastasis. Reverse transcription-quantitative polymerase chain reaction data revealed that miR-22 was significantly downregulated in breast cancer tissues, compared with adjacent non-tumor tissues. Furthermore, the miR-22 levels were further decreased in stage III-IV, compared with stage I-II breast cancer. In addition, low miR-22 levels were significantly associated with the poor differentiation, metastasis and advanced clinical stages of breast cancer. Sirtuin1 (SIRT1) was demonstrated to act as a direct target gene of miR-22 and its protein expression negatively regulated by miR-22 in the MCF-7 breast cancer cell line. Furthermore, SIRT1 expression levels were significantly upregulated in breast cancer tissues, compared with adjacent non-tumor tissues. SIRT1 levels were observed to be increased in stage III-IV when compared with stage I-II breast cancer. miR-22 overexpression decreased the proliferation, migration and invasion of MCF-7 cells, whereas overexpression of SIRT1 eliminated the suppressive effects of the miR-22 overexpression on the malignant phenotype of MCF-7 cells. The results of the present study therefore suggested that miR-22 demonstrated suppressive effects on breast cancer growth and metastasis via targeting SIRT1, and thus the miR-22/SIRT1 axis may be used as a novel and potential therapeutic target for breast cancer in the future. 

Retracted: Yes

PubPeer comments:
 Figs 3B, D.  Western blot was conducted to examine the protein levels of SIRT1 .  Other manifestations of these bands include Fig 6B from [Zhou et al (2017)] . Figs 7A,B, 9B from [Liu et al (2017)] . Figs 3B, 4B from [Dang et al (2017)] . Fig 4A from [Jiang et al (2017)] .  Fig 7 of [Dai et al (2016)] .  , 
 Retracted [19 August 2021] . --------------------------------- Following the publication of this paper, it was drawn to the Editorsu2019 attention by a concerned reader that the western blotting data shown in Fig. 3B and D were strikingly similar to data appearing in different form in other articles by different authors. 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 *Experimental and Therapeutic Medicine*, 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 any reply. The Editor apologizes to the readership for any inconvenience caused. ,