MicroRNA-33b inhibits cell proliferation and glycolysis by targeting hypoxia-inducible factor-1Œ± in malignant melanoma
Authors: Yue Zhao
Lina Li
Cuiling Wu
Journal: Experimental and Therapeutic Medicine (2017)
Discipline: CLINICAL MEDICINE
Keywords: glycolysis; hypoxia-inducible factor-1Œ±; melanoma; microRNA; proliferation.
Affiliations: Department of Dermatology, Heping Hospital of Changzhi Medical College, Changzhi, Shanxi 046000, P.R. China., Department of Biochemistry, Changzhi Medical College, Changzhi, Shanxi 046000, P.R. China., Department of Pathology, Changzhi Medical College, Changzhi, Shanxi 046000, P.R. China.

Abstract:  Malignant melanoma (MM) is the most aggressive type of skin cancer. MicroRNA (miR) has been implicated in the development and progression of MM; however, their underlying mechanism of action remains largely unknown. The present study aimed to investigate the role of miR-33b in MM. Reverse transcription-quantitative polymerase chain reaction data indicated that the expression of miR-33b was significantly reduced (P&lt;0.01) in MM cell lines, including WM35, WM451 and SK-MEL-1, when compared with human melanocyte cells. Subsequently, WM451 and SK-MEL-1 cells were transfected with an miR-33b mimic or inhibitor. MTT assay data demonstrated that the viability of MM cells markedly decreased following miR-33b overexpression; however, viability was markedly upregulated following miR-33b knockdown. Additionally, the glycolysis level was examined. Results demonstrated that glucose consumption and lactic acid production were significantly downregulated (P&lt;0.01) after miR-33b upregulation, whereas these levels significantly increased in MM cells transfected with miR-33b inhibitor (P&lt;0.01), suggesting that miR-33b negatively mediates the glycolysis level in MM cells. Bioinformatics indicated that hypoxia-inducible factor (HIF)-1Œ± was a putative target gene of miR-33b, and this was confirmed by a luciferase reporter assay, which demonstrated that miR-33b was able to directly bind to the 3' untranslated region of HIF-1Œ± mRNA. Furthermore, the expression of HIF-1Œ± was negatively regulated by miR-33b at the post-transcriptional level in MM cells. Overexpression of HIF-1Œ± reversed the inhibitory effect of miR-33b on the proliferation and glycolysis in MM cells. Finally, the results of the present study demonstrated that hexokinase 2 and lactate dehydrogenase-A may be involved in miR-33b/HIF-1Œ± mediated glycolysis in MM cells. In conclusion, these results suggest that miR-33b inhibits cell proliferation and glycolysis by targeting HIF-1Œ± in MM. 

Retracted: Yes

PubPeer comments:
 Figs 5, 6.  pcDNA3.1-HIF-1u03b1 plasmid was transfected into miR-33b-overexpressing WM451 and SK-MEL-1 cells. Western blot analysis was conducted to examine the expression of HIF-1u03b1 protein in (A) WM451 and (B) SK-MEL-1 cells transfected with miR-33b mimic or co-transfected with miR-33b mimic and pcDNA3.1-HIF-1u03b1 plasmid ;  Western blot analysis was conducted to examine the expression of HK2 and LDH-A protein in (A) WM451 and (B) SK-MEL-1 cells transfected with miR-33b mimic or co-transfected with miR-33b mimic and pcDNA3.1-HIF-1u03b1 plasmid .  The bands marked with red and orange boxes are versatile. 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)] .  Pink, light blue, green boxes mark similar lanes in Figs 4C,D of [Zhou et al (2016)] ,  Western blot was used to examine the protein levels of EMT-related genes . Other manifestations are linked in that thread.  , 
 #1 Adventures in Western Blot versatility: *[above]* Fig 3B,C from [Wu et al (2017)] .  Western blotting was used to measure the expression of DKK3 in U2OS cells transfected with (B) miR-NC and miR-92b mimic, as well as in U2OS cells transfected with (C) NC inhibitor and miR-92b inhibitor. *[middle]* **Fig 6A from [Zhao, Wu Li (2017)] **.  Western blot analysis was conducted to examine the expression of HK2 and LDH-A protein in (A) WM451 ... cells transfected with miR-33b mimic or co-transfected with miR-33b mimic and pcDNA3.1-HIF-1u03b1 plasmid . With 180-deg flipped version. *[below]* Figs 4D from [Zhou et al (2016)] ,  Western blot was used to examine the protein levels of EMT-related genes ; and Fig 2C from [Chen et al (2016)] ,  Western blot was conducted to determine the protein level of HIF-1u03b1 in WM451 cells transfected with NC and HIF-1u03b1 siRNA, respectively *[vertically stretched]*.  , 
 Retracted, [13 September 2021] . ------------------------------------- Following the publication of this paper, it was drawn to the Editorsu2019 attention by a concerned reader that the western blotting assay data shown in Figs. 5 and 6 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. 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. ,