Long non‑coding RNA TTN‑AS1 promotes breast cancer cell migration and invasion via sponging miR‑140‑5p
Authors: Xiaona Li
Zhixia Zhang
Qingfang Ren
Jie Xue
Qinghua Wang
Journal: Oncology Letters (2019)
Discipline: CLINICAL MEDICINE
Keywords: BC; TTN-AS1; long non-coding RNA; miR-140-5p.
Affiliations: Department of Breast Surgery, Linyi Cancer Hospital, Linyi, Shandong 276000, P.R. China., Department of Medical Oncology, Linyi Cancer Hospital, Linyi, Shandong 276000, P.R. China.

Abstract:  Breast cancer (BC) is one of the most common fatal cancers. Recent studies have identified the vital role of long non-coding RNAs (lncRNAs) in the development and progression of BC. In this investigation, lncRNA TTN-AS1 was studied to identify its function in the metastasis of BC. TTN-AS1 expression of tissues was detected by real-time quantitative polymerase chain reaction (RT-qPCR) in 56 BC patients. Wound healing assay and transwell assay were used to observe the biological behavior changes of BC cells through gain or loss of TTN-AS1. In addition, luciferase assays and RNA immunoprecipitation (RIP) assay were performed to discover the potential targets of TTN-AS1 in BC cells. TTN-AS1 expression level in BC samples was higher than that of adjacent tissue. Besides, the ability of cell migration and invasion of BC cells was inhibited after TTN-AS1 was silenced, while cell migration and cell invasion of BC cells were promoted after TTN-AS1 was overexpressed. In addition, miR-140-5p was upregulated after silencing of TTN-AS1 in BC cells, while miR-140-5p was downregulated after overexpression of TTN-AS1 in BC cells. Furthermore, luciferase assays and RIP assay showed that miR-140-5p was a direct target of TTN-AS1 in BC. Our study uncovered a new oncogene in BC and suggests that TTN-AS1 enhances BC cell migration and invasion via sponging miR-140-5p, which provides a novel therapeutic target for BC patients. 

Retracted: Yes

PubPeer comments:
 This paper is one of a set of 121 papers that all contain images from the same library of about 100 photos and plots. This is unexpected, because each paper has different authors and different affiliations, with little to no overlap, and describes different cancer types and molecules. It would be very hard to explain how authors from different labs would all obtain the same photo. Therefore, the papers might have all be derived from the same source, such as a paper mill that sells ready-to-be-published papers. This  Stock Photo paper set has been described in more detail on my blog post, https: scienceintegritydigest.com 2020 07 05 the-stock-photo-paper-mill and in a Wall Street Journal article by Eva Xiao (currently behind a paywall): https: www.wsj.com articles chinese-research-papers-raise-doubts-fueling-global-questions-about-scientific-integrity-11593939600 The vast majority (113 121) of the papers were published in the same journal, European Review for Medical and Pharmacological Sciences (ERMPS). A link to the full set of papers can be found here: https: docs.google.com spreadsheets d 172RWS18w1lTNJ9Nnj80fuXXTqTm4fGkoK0sdYyvKE3g edit?usp=sharing All papers have been reported to the journal editors on July 2, 2020. , 
 Retracted [25 August 2020] ---------------------------------------------------- Following the publication of this article, the authors contacted the Editor to request its retraction on account of having been unable to obtain the same results on performing further experiments. Subsequently, the Editorial office were also informed by an interested reader that data featured in Figs. 2 and 3 had also appeared in other non-related publications, and the office were able to confirm that these images were indeed the same as those featured in the other publications. The Editor has agreed to the authorsu2019 request, and therefore this article has been retracted from Oncology Letters. All the authors agree to this retraction. The authors apologize to the readership of the Journal for any inconvenience caused. ,