Expression of Concern
This article is currently under investigation. We strongly recommend that this article is not cited until the investigation is completed.
Research Paper Volume 11, Issue 18 pp 7678—7693

Long noncoding RNA TTN-AS1 enhances the malignant characteristics of osteosarcoma by acting as a competing endogenous RNA on microRNA-376a thereby upregulating dickkopf-1

class="figure-viewer-img"

Figure 5. DKK1 mRNA is a direct target of miR-376a in OS cells. (A) MiR-376a and its wild-type binding site in the 3′-UTR of DKK1 mRNA. The mutations were introduced into the site complementary to the seed region of miR-376a. (B) The luciferase reporter assay was performed to test whether the 3′-UTR of DKK1 mRNA could be directly targeted by miR-376a in OS cells. HOS and MG-63 cells were cotransfected with either agomir-376a or agomir-NC and either the DKK1-wt or DKK1-mut plasmid. After 48 h of cultivation, the transfected cells were assayed with the Dual-Luciferase Reporter Assay System to measure the luciferase activity. *P < 0.05 vs. the agomir-NC group. (C, D) Expression levels of DKK1 mRNA and protein in miR-376a-overexpressing HOS and MG-63 cells were respectively determined by RT-qPCR and western blotting. *P < 0.05 vs. the agomir-NC group. (E) RT-qPCR was carried out to measure DKK1 mRNA expression in the 47 pairs of OS tissue samples and adjacent-normal-bone tissue samples. *P < 0.05 vs. the normal bone tissues. (F) Spearman’s correlation analysis confirmed the negative correlation between DKK1 mRNA and miR-376a levels among the OS tissues. r = -0.6236, P < 0.0001.