Effects Of LncRNA-ATB On The Proliferation And Apoptosis Of Keloid Fibroblasts And Its Mechanism

ObjectiveTo investigate the effects of Long non-coding RNA activated by transf orming growth factor-b(Lnc RNA-ATB)on proliferation and apoptosis of kelo id fibroblasts and to analyze its mechanism.MethodsReverse transcription-polymerase chain reaction(RT-PCR)was used to detect the expression levels of ATB,micro RNA-200c(mi R-200c)and DNA methyltranserase DNMT3B(DNMT3B)in keloids and normal skin tissues,and the correlation between the three was analyzed.After fibroblasts trans fected with sh-ATB,o/e-ATB,mi R-200 c mimics,mi R-200 c inhibitors and sh-DNMT3 B,the cell proliferation was detected by cell counting kit-8(CCK8)assay;cell apoptosis was detected by flow cytometry;The dual luciferase assay was used to detect the binding of ATB and mi R-200 c,and mi R-200 c and DNMT3 B.The expression levels of proliferation-related molecule Cy clin-dependent kinase 6(CDK6)and apoptosis-related molecule caspase-3were detected by Western blot and RT-PCR.ResultsThe expression levels of ATB and DNMT3 B in keloid tissues were significantly higher than those in normal skin(P<0.05).The expression level of mi R-200 c in keloid tissues was lower than that in normal skin(P<0.05).ATB andmi R-200c(rs=-3.429),and mi R-200 c and DNMT3B(rs=-2.011)were significantly negatively correlated in keloid tissue(P<0.05).The dual luciferase results showed that ATB was able to target the binding of mi R-200 c,and mi R-200 c was able to target DNMT3 B.After transfection of sh-ATB or mi R-200 c mimics in keloid fibroblasts,the proliferation of cells and the expression of proliferation-related molecules CDK6 were significantly decreased(P<0.05),apoptosis rate and the expression of apoptosis-related molecules caspase-3were significantly increased(P<0.05).In the recovery experiment,co-transfection of sh-ATB and mi R-200 c inhibitors in keloid fibroblasts reversed the effects of single transfection of sh-ATB on cell proliferation and apoptosis(P>0.05).Co-transfection o/e-ATB and mi R-200 c inhibitors could further enhance the effects of single transfection of o/e-ATB on cell proliferation and apoptosis(P<0.05).Co-transfection of mi R-200 c inhibitors and sh-DNMT3 B in keloid fibroblasts could reverse the effects of single transfection of mi R-200 c inhibitors on cell proliferation and apoptosis(P>0.05).Co-transfection of mi R-200 c mimics and sh-DNMT3 B can further enhance the effect of single transfection of mi R-200 c mimics on cell proliferation and apoptosis(P < 0.05).ConclusionsATB was highly expressed in keloid tissue,and low expression of AT B could inhibit fibroblast proliferation and promote apoptosis by regulating mi R-200c/DNMT3 B pathway.