MicroRNA-16 inhibits the proliferation, migration and invasion of glioma cells by targeting Sal-like protein 4
Authors: Chao Hu
Yu Zhou
Yang Liu
Yugang Jiang
Journal: International Journal of Molecular Medicine (2016)
Discipline: CLINICAL MEDICINE
Keywords: MicroRNAs; miR-16; glioma; SALL4; tumor suppressor
Affiliations: Department of Neurosurgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China., Department of Rehabilitation, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China., Department of Radiology, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China.

Abstract:  MicroRNAs (miRNAs or miRs), a class of non-coding RNAs 18-25 nucleotides in length, act as key regulators in the development and malignant progression of various human cancers by modulating the expression of their target genes. Recently, miR‑16 has been demonstrated to be play a role in glioma. However, the regulatory mechanisms of miR‑16 in glioma growth and metastasis remain largely unclear. In the present study, qRT-PCR revealed that miR‑16 was significantly downregulated in 23 glioma tissue specimens compared to 7 normal brain tissue specimens. Moreover, its levels were markedly lower in the glioma samples at stages T2-T4 compared to those at stage T1. The overexpression of miR-16 significantly suppressed the proliferation, migration and invasion of U251 and U87 glioma cells. Luciferase reporter assay identified Sal-like protein 4 (SALL4) as a target gene of miR‑16, and its protein levels were found to be decreased in miR‑16-overexpressing U251 and U87 cells. Furthermore, the overexpression of SALL4 significantly reversed the suppressive effects of miR‑16 on the proliferation, migration and invasion of U251 and U87 cells, suggesting that miR‑16 playsa tumor suppressor role in glioma by inhibiting cell proliferation and invasion through the targeting of SALL4. Finally, we found that SALL4 was significantly upregulated in glioma tissues compared to normal brain tissues, and its levels were markedly higher in the glioma tissues at stages T2-T4 compared to those at stage T1. In addition, the expression levels of SALL4 inversely correlated with the miR‑16 levels in glioma tissues, suggesting that the downregulation of miR‑16 contributes to the upregulation of SALL4 in glioma. On the whole, the findings of this study indicate a role for the miR‑16/SALL4 axis in glioma. Our data may also provide a potential therapeutic target for the treatment of glioma. 

Retracted: No

PubPeer comments:
 Figs 3H, 4A B.  western blot analysis were used to examine the ... protein levels, respectively of SALL4 in U87 and U251 cells transfected with scramble miR (control) or miR-16 mimic ;  U87 and U251 cells were transfected with miR-16 mimic with or without pc-DNA3.1-Sal-like protein 4 (SALL4) plasmid. (A and B) Following transfection, the protein level of SALL4 was then examined by western blot analysis. ![file] For comparison: Fig 6B from [Zhou et al (2017)] :  miR-181b-overexpressing U251 cells were transfected with SALL4 expression plasmid or blank vector. (A) RT-PCR and (B) Western blot were used to examine the mRNA and protein levels of SALL4 . Figs 7A,B, 9B from [Liu et al (2017)] .  A549 and H1229 cells were transfected with the miR-98 mimic or co-transfected with the miR-98 mimic and pcDNA3.1-SALL4 expression plasmid. (A, B) Western blot was conducted to examine the protein expression of SALL4 ...  A549 cells were stably transfected with the blank pLP VSVG vector as control, pLP VSVG-miR-98 lentiviral plasmid, or pLP VSVG-SALL4 lentiviral plasmid. ... (B) Western blot was used to examine the protein levels of SALL4 . Figs 3B, 4B from [Dang et al (2017)] .  Western blot were conducted to examine the ... protein expression of CXCL5 in U2OS cells transfected with CXCL5 siRNA or nonspecific siRNA as negative control (NC) ...  Western blot were conducted to examine the ... protein expression of CXCL5 in U87 cells transfected with CXCL5 expression plasmid or blank vector as control . Fig 4A from [Jiang et al (2017)] .  Western blot was used to detect the protein expression of IGF2BP1 in LM3 cells transfected with miR-98-5p mimic or scramble miR (miR-NC), respectively . ![file] Lots of unexpected similarities. , 
 *[above]* Fig 5C.  Western blot analysis was used to determine the protein level of SALL4 in glioma tissues (T) and normal brain tissues (N) . This would be more convincing if it were not for *[below]* Fig 6B from [Jiang et al (2017)] .  Western blot were used to detect the ... protein levels of IGF2BP1 in HCC tissues compared to matched adjacent nontumor tissues. ![file] , 
 #1 Figs 3H, 4A again. *[below]* Figs 4C D from [Zhou et al (2016)] .  Western blot was used to examine the protein levels of EMT-related genes . ![file] , 
 #3 *[left]* Fig 4A. *[right]* Fig 5B from [Li et al (2018)] .  Western blot were used to examine the... protein expression of PRRT2 in U87 and A172 cells transfected with the miR-30b inhibitor or negative control (NC) inhibitor . ![file] , 
 #3 Figs 3H, 4A again; and *[below]* Figs 4C D from Zhou et al (2016), again. More colored boxes, ![] To match Fig 7 of [Dai et al (2016)] . ![] . , 
 #4 *[left]* Fig 4A. *[right]* Fig 5B from Li et al (2018). *[below]* Another sighting! Fig 3F of [Xu et al (2018)] .  Western blotting was used to examine the protein levels of PANX2 in (F) U251 ... cells transfected with miR-423-3p inhibitor or NC inhibitor . ![file] ,