MicroRNA‑181 serves an oncogenic role in breast cancer via the inhibition of SPRY4
Authors: Liangfang Shen
Yifu Tian
Qin Zhou
Qingling Li
Xiaodan Fu
Weilu Kuang
Dan Fan
Ying Wang
Journal: Molecular Medicine Reports (2018)
Discipline: CLINICAL MEDICINE
Keywords: microRNAs; miR-181; breast cancer; regulatory mechanism; cell proliferation
Affiliations: Department of Pathology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China., Department of Oncology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China.

Abstract:  Numerous microRNAs (miRs) have been implicated in breast cancer; however, the molecular mechanism is not fully understood. The present study examined the function and regulatory mechanism of miR‑181 in breast cancer. Reverse transcription‑quantitative polymerase chain reaction and western blot analysis were used to examine the RNA and protein expression. MTT assay, wound healing assay and transwell assay were conducted to study cell proliferation, migration and invasion. Luciferase reporter gene assay was used to confirm targeting relationship. The results suggested that the miR‑181 expression levels were significantly higher in breast cancer cell lines and clinical tissue samples. The increased expression of miR‑181 was markedly associated with higher clinical stage and lymph node metastasis. The patients with high miR‑181 expression demonstrated worse prognosis compared with those with a low expression of miR‑181. Small interfering RNA‑induced miR‑181 downregulation significantly inhibited breast cancer cell proliferation, migration and invasion in vitro, and tumor growth in vivo. Protein sprouty homolog 4 (SPRY4), downregulated in breast cancer tissues and cell lines, was observed to be a novel target gene of miR‑181. Downregulation of SPRY4 was significantly associated with breast cancer progression in addition to poor prognosis. Knockdown of SPRY4 rescued the inhibitory effects of miR‑181 downregulation on the malignant phenotypes of breast cancer cells. Thus, the present study demonstrated that miR‑181 serves a promoting role in breast cancer at least in part through the inhibition of SPRY4 expression. The present results expand the understanding of the miR‑181/SPRY4 axis' function during for the malignant progression of breast cancer. 

Retracted: Yes

PubPeer comments:
 Figs 3B, 9B. Cell invasion assays. ![file] These are versatile figures. Figs 2D, 5E from [Liang et al (2017)] ... ![file] ...Figs 3 C,D and 8 C,D from [Liu et al (2017)] . ![file] Other manifestations are linked in those threads. , 
 Duplicate comment, deleted. , 
 Retracted [4 March 2022] .  Following the publication of this paper, it was drawn to the Editorsu2019 attention by a concerned reader that the Transwell cell migration assay data shown in Figs. 3B and 9B 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 *Molecular Medicine Reports*, the Editor has decided that this paper should be retracted from the Journal. After having been in contact with the authors, they agreed with the decision to retract the paper. The Editor apologizes to the readership for any inconvenience caused. ,