Study on suppressions of proliferation and invasion of osteosarcoma cells by all-trans-retinoic acid via modulating miRNA-34a-E2F1-Eag1 signaling pathway in vitro / 肿瘤研究与临床

ABSTRACT

Objective:To investigate the influence of all-trans-retinoic acid (ATRA) on the proliferation and invasion of osteosarcoma 143B cells and its possible regulatory mechanism.Methods:Different concentrations of ATRA were used to treat human osteosarcoma 143B cells, and the optimal concentration and treatment time those affected cell proliferation were selected. The MTS method, Transwell migration and invasion experiments were used to detect the changes in the proliferation, migration and invasion of 143B cells after ATRA treatment. The real-time quantitative polymerase chain reaction (qRT-PCR) and Western blot were used to detect the expression changes of miRNA-34a (miR-34a), E2F1 and Eag1 in osteosarcoma 143B cells after ATRA treatment. Then miR-34a was interfered and E2F1 was overexpressed, and the abilities of cell proliferation, invasion and migration abilities as well as the expression changes of miR-34a, E2F1 and Eag1 in 143B cells were detected.Results:The proliferation inhibition of 143B cells was most obvious when 143B cells were treated with 10 μmol/L ATRA for 72 h. The cell migration and invasion numbers when 143B cells were treated with 10 μmol/L ATRA for 72 h were lower than those in the negative control group [(73±3) cells vs. (182±5) cells, t = 21.46, P<0.01; (94±3) cells vs. (203±7) cells, t = 13.70, P<0.01]. 10 μmol/L ATRA could promote the expression of miR-34a in 143B cells and inhibit the expressions of Eag1 and E2F1 (all P<0.01). Compared with ATRA group, the ability of cell proliferation in ATRA+miR-34a interference group was restored after 72 h of treatment [cell survival rate (41.0±2.2)% vs. (25.0±3.6)%, t = 108.68, P<0.01]. Compared with ATRA group, the abilities of cell migration and invasion in ATRA+miR-34a interference group were restored [(122±14) cells vs. (64±10) cells, t = 21.06, P<0.01; (103±10) cells vs. (59±8) cells, t = 24.27, P<0.01), and the mRNA and protein expressions of Eag1 and E2F1 in cells were promoted (both P<0.01). Compared with ATRA group, the ability of cell proliferation in ATRA+E2F1 overexpression group was restored [cell survival rate (40.0±3.4)% vs. (24.0±3.1)%, t = 108.74, P<0.01]; the abilities of cell migration and invasion in ATRA+E2F1 overexpression group were restored [(78±12) cells vs. (29±8) cells, t = 13.52, P<0.01; (75±12) cells vs. (49±10) cells, t = 6.28, P<0.01], and the mRNA and protein expressions of Eag1 and E2F1 in cells were promoted (both P<0.01). Conclusion:ATRA inhibits the proliferation and invasion of osteosarcoma cells via regulating miR-34a-E2F1-Eag1 signaling pathway, and it may become one of the effective treatment drugs for osteosarcoma.