lncRNA SNHG3 promotes breast cancer�progression by acting as a miR‑326 sponge
Authors: Na Wei
Qian Li
Rongbo Ding
Lishennan Shen
Ye Du
Wei Zhang
Simin Li
Haipeng Zhang
Journal: Oncology Reports (2020)
Discipline: CLINICAL MEDICINE
Keywords: SNHG3; small nucleolar RNA host gene 3; miR-326; breast cancer; proliferation
Affiliations: Department of Gynecology, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R.�China, Department of First Operating Room, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R.�China, Department of Cosmetology Plastic Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R.�China, Department of Breast Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R.�China

Abstract:  Accumulating evidence suggests that long noncoding RNA (lncRNA) small nucleolar RNA host gene 3 (SHNG3) plays crucial roles in the initiation and progression of various types of malignant cancers. Yet, the role played by SNHG3 in breast cancer as well as the associated mechanisms remain largely unclear. The expression of SNHG3 was detected in breast cancer tissues and cell lines by reverse‑transcription quantitative PCR (RT‑qPCR). Cell proliferation, colony formation, cell cycle distribution, migration and invasion abilities were detected by Cell Counting Kit‑8, colony formation assay, flow cytometry, wound‑healing and Matrigel invasion assays, respectively. The regulatory relationships between SNHG3 and miR‑326 were explored by luciferase reporter assay. A nude mouse model was established to investigate the effect of SNHG3 in vivo. The results showed an upregulation of SNHG3 in breast cancer tissues and cell lines. Loss‑of‑function assays revealed significant suppression of breast cancer behaviors such as: Abilities to proliferate, form colonies, migrate and invade in vitro coupled with a delayed growth of tumors in vivo when SNHG3 was knocked down. Mechanically, it was shown that SNHG3 served as a competing endogenous RNA (ceRNA) of miR‑326 that in turn is a tumor suppressor in this cancer. The correlation between the expression of SNHG3 and miR‑326 was found to be strongly negative in these samples. Additionally, we found that inhibition of SNHG3 caused a partially reversal in the inhibition exerted by miR‑326 on the ability of these cells to proliferate, form colonies, migrate and invade. Collectively, these findings suggest the functioning of SNHG3 as a ceRNA to enhance the ability of breast cancer cells to proliferate and metastasize to putatively serve as a new target to explore therapeutic intervention of this malignancy. 

Retracted: Yes

PubPeer comments:
 Fig 2C.  colony formation... determined in MCF-7 cells transfected with sh-NC or sh-SNHG3 . ![file] Yellow boxes mark a repeated area. Red circle is for comparison with *[left]* Fig 5C from [Li et al (2017a)] .  colony formation ... detected in SCC9 cells transfected with miR-NC or and miR-152 mimic with without c-MET overexpression plasmid . *[right]* Fig 5C from [Li et al (2017b)] .  colony formation ... determined in SKOV3 cells transfected with miR-218 mimic or miR-NC with or without RUNX2 overexpression plasmid . ![] Light green circle is for comparison with Fig 2C from [Liu et al (2017)] .  colony formation ... determined in HepG2 cells transfected with miR-365 mimic or miR-NC. ![file] , 
 Fig 6B.  Representative image of isolated tumors from nude mice in the sh-NC and sh-SNHG3 groups. ![file] The image of the ruler also features in Fig 7B from [Fei et al (2020)] .  Representative images of formed tumors that were subcutaneously injected with U2OS cells stable transfected with sh-AFAP1-AS1 and sh-NC plasmid. ![file] Fig 6B from [Wen et al (2020)] .  Tumor images was captured at the end of the experiments . ![file] Fig 7B of [Zhang et al (2019)] .  Representative images of xenograft tumours . ![file] ![file] That is, the image is a digital composite (which also explains the inconsistencies of shadows and lighting), which detracts from any sense of consistent scale provided by that ruler. , 
 Retracted [4 January 2022] .  Following the publication of the above article, the authors have requested that it be retracted. Subsequently to having performed these experiments, the authors have realized that their MCFu20117 cells had become contaminated while performing the colony formation and transwell experiments. Furthermore, they were unable to reproduce the results from the in vivo experiments, and knockdown of SNHG3 was found not to affect tumor growth in nude mice. Following a further investigation in the Editorial Office, it also came to light that there were other possible anomalies associated with the presentation of the tumor images in Fig. 6B and the colony formation assay data in Fig. 2C. Therefore, theos article has been retracted from the Journal; all the authors agree to this retraction. The Editor and the authors would like to apologize for any inconvenience caused. ,