Extracellular lncRNA TTN-AS1 Mediates miR-524-5p through TGFβ/Smads Pathway Regulating the Progress of Breast Cancer
Objective:To investigate the molecular mechanism of extracellular long chain non coding RNA(lncRNA)TTN-AS1 mediated miR-524-5p through transforming growth factor β(TGF β/Smads signaling pathway,then to regulate the breast cancer progression.Methods:Firstly,real-time fluorescence quantitative polymerase chain reaction(qRT-PCR)was used to detect the expressions of lncRNA TTN-AS1 and miR-524-5p in human breast cancer cell MDA-MB-231,MCF-7,SKBR-3 and breast epithelial cell MCF-10A,Western blot was to detect TGF β1 and p-Smad2 proteins expression.Then,cell transfection technology was used to inhibit expression of lncRNA TTN-AS1,lncRNA TTN-AS1,miR-524-5p,TGFβ1 and p-Smad2 expressions were compared between MDA-MB-231(negative control)and transfection group.CCK8 method was to detect cell proliferation,flow cytometry was to detect cell apoptosis rate,and Transwell chamber was to detect cell migration.Results:Compared with MCF-10A,the expression levels of lncRNA TTN-AS1 in MDA-MB-231,MCF-7,SKBR-3 were significantly higher,while miR-524-5p were significantly less,TGFβ1 and p-Smad2 were upregulated(P<0.05).Compared with the negative control group,the expressions of lncRNA TTN-AS1 in the transfection group was significantly lower,while miR-524-5p was significantly more,resulting in TGF β1 and p-Smad2 were downregulated(P<0.05).The cell proliferation rate and the number of migrating cells were significantly less,while the apoptosis rate was higher(P<0.05).Conclusion:lncRNA TTN-AS1 may play a cancer promoting role in the progression of breast cancer by inhibiting the expression of miR-524-5p and activating TGF β1/Smad2 signaling pathway,which is involved in regulating the proliferation and apoptosis of breast cancer.LncRNA TTN-AS1 is expected to become a new molecular site targeting breast cancer intervention.
Breast cancerLncRNA TTN-AS1MiR-524-5pTransforming growth factor βSignal pathwayProliferationApoptosis