Long non-coding RNA TTTY15 expression in osteosarcoma and its effect on viability and invasion ability of osteosarcoma cells / 中国病理生理杂志

ABSTRACT

AIM:To observe the expression of long noncoding RNA TTTY 15 in osteosarcoma tissues and cell lines and to explore its effect on the viability and invasion ability of osteosarcoma cell lines.METHODS:qPCR was used to detect the expression of TTTY15 in 11 cases of osteosarcoma and its adjacent tissues.The mRNA levels of TTTY15 in os-teosarcoma cell lines(143B,Saos2,MG-63,U2OS and HOS)and human osteoblast cell line hFOB1.19 were also tested. TTTY15 was down-regulated after transfected with small interfering RNA in MG-63 cells,the cell line with the highest level of TTTY15.The effect of TTTY15 knockdown on the viability of MG-63 cells was measured by CCK-8 assay.The cell cycle distribution was analyzed by flow cytometry.The effect of TTTY15 knockdown on the cell invasion ability was detected by Transwell assay.The levels of miR-216b-5p and FOXM1 mRNA were detected by qPCR, and the changes of the related proteins were determined by Western blot.RESULTS:Compared with the adjacent tissues,the expression of TTTY15 in-creased in the osteosarcoma tissues(P<0.01).Compared with the human osteoblast cell line,the expression of TTTY15 increased in the osteosarcoma cell lines(P<0.05), and the level of TTTY15 in the MG-63 cells was the highest(P<0.01).After knockdown of TTTY15 expression in the MG-63 cells,the cell viability was decreased(P<0.05),cell cycle progression was inhibited(P<0.01), and the cell invasion ability was decreased(P<0.01).The expression of miR-216b-5p was increased(P<0.01)and the expression of FOXM1 mRNA was decreased(P<0.01).The protein expres-sion of FOXM1,CDK4,cyclin D1,MMP-2 and N-cadherin was decreased,while the protein expression of E-cadherin was increased(P <0.05).CONCLUSION: The expression of TTTY15 is increased in the osteosarcoma tissues and cell lines.The low expression of TTTY15 inhibits the cell viability and invasion ability of osteosarcoma cells.The possible mechanism is that the knockdown of TTTY 15 expression results in the increase in miR-216b-5p expression and the down-regulation of FOXM1 expression.