The study about the mechanism about elemene inducing apoptosis of neuroblastoma

Objective To investigate the effect of elemene on the apoptosis of neuroblastoma, and study the mechanism. Methods We cultured the SK-N-SH cell line, used the cell counting kit-8 (CCK-8) assay to calculate inhibition rate. We also used the flow cytometry to measure the apoptosis rate. The mRNA expression of cysteinyl aspartate-specific protease (Caspase)-3 and Caspase-9 was analyzed by real-time quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR). Caspase-3 and Caspase-9 activities were also analyzed. Results Elemene significantly induced the apoptosis of SK-N-SH cell in a dose and time dependent manner. [inhibition rate=(10.963±2.994)%, (50.013±3.641)%, (77.515±4.612)%, t=4.220, 5.615, 8.096, P=0.022, 0.000, 0.000 at each indicated concentration point of 24 h; inhibition rate=(14.478±2.270)%, (56.387±3.494)%, (79.531±3.874)%, t=4.229, 5.379, 7.842, P=0.021, 0.000, 0.000 at each indicated concentration point of 48 h; (24.174±2.920)%, (64.619±3.180)%, (87.375±4.189)%, t=4.759, 6.773, 15.384, P=0.001, 0.000, 0.000 at each indicated concentration point of 72 h]. Additionally elemene dramatically induced the apoptosis of SK-N-SH cell [the apoptosis rate=(19.280±2.991)%, (52.493±4.379)%, (82.189±3.175)%, t=4.166, 6.324, 9.703, P=0.048, 0.000, 0.000 at each indicated concentration point]. Moreover, the mRNA expression of Caspase-3 and Caspase-9 were markedly increased by elemene [increased folds=(2.712±0.127), (3.013±0.304), (3.931±0.410), t=4.714, 6.079, 9.318, P=0.015, 0.000, 0.000 for Caspase-3 expression at each indicated concentration point; increased folds=(1.206±0.136), (2.331±0.412), (2.824±0.410), t=4.874, 7.523, 10.530, P=0.038, 0.010, 0.000 for Caspase-9 expression at each indicated concentration point]. Furthermore, elemene significantly up-regulated the activations of Caspase-3 and Caspase-9 [increased folds=(1.517±0.192), (2.016±0.323), (2.081±0.361), t=5.175, 7.107, 12.100, P=0.005, 0.001, 0.000 for Caspase-3 activation at each indicated concentration point; increased folds=(1.672±0.331), (2.100±0.276), (2.328±0.361), t=4.605, 6.532, 15.101, P=0.003, 0.011, 0.000 for Caspase-9 activation at each indicated concentration point]. Conclusion Elemene could significantly induced the apoptosis of neuroblastoma through activations of Caspase-3 and Caspase-9. Key words: Elemene; Neuroblastoma; Apoptosis; Cysteinyl aspartate-specific protease-3; Cysteinyl aspartate-specific protease-9