Effect of cisplatin on NOD1 and NOD2 expression in SaOS-2 cell line

Abstract

Objective To investigate the effects of cisplatin on the expression of nucleotide-binding oligomerization domain-like receptor(NOD) 1 and 2 in human osteosarcoma SaOS-2 cell line, and to explore the mechanism of cisplatin in the treatment of human osteosarcoma. Methods CCK-8 assay, real-time quantitative reverse transcription polymerase chain reaction(qRT-PCR) and immumofluorescence methods were used to determine the growth survival rate and expression levels of NOD1 and NOD2 in osteosarcoma SaOS-2 cell line treated with cisplatin (0, 5, 10, 20 μmol/L, named group S0, group S5, group S10, group S20, respectively) for 24, 48, 72 hours. Results After treatment with cisplatin for 48 h or 72 h, the growth survival rates of SaOS-2 cells were significantly decreased in group S5 than those in group S0(65.53% vs.100.00%; 46.43% vs.100.00%, χ2=8.64, 73.97, all P<0.01). Moreover, after treatment with cisplatin for 24 h, 48 h or 72 h, the growth survival rates of SaOS-2 cells were significantly decreased in group S10 or group S20 than those in group S0(80.60% vs.100.00%, 42.94 vs.100.00%, 27.90% vs.100.00%; 62.54% vs.100.00%, 33.09% vs.100.00%, 22.95% vs.100.00%, χ2=20.99, 79.72, 112.50; 45.40, 67.56, 125.20, all P<0.01), and the growth survival rates were significantly lower in group S20 than those in group S5(62.54% vs.93.78%, 33.09% vs.65.53%, 22.95% vs.46.43%, χ2=28.47, 21.78, 11.71, all P<0.01). The expression levels of NOD1 mRNA and NOD2 mRNA in group S5 were significantly increased at 48 h or 72 h than those at 24 h, and were higher than group S0 when treated with 5μmol/L cisplatin[(3.64±0.44) vs.(4.47±1.22) vs.(1.79±0.44) vs (1.00±0.00); (6.88±2.79) vs.(6.86±2.40) vs (2.29±0.70) vs.(1.00±0.00), F=29.12, 24.11, all P<0.01]. And the expression levels of NOD1 protein had an increased tendency after 48 h or 72 h treatment with 5μmol/L cisplatin.Furthermore, the expression level of NOD1 mRNA was positively correlated with NOD2 mRNA(n=36, r=0.92, P<0.01). Conclusion Cisplatin can elevate the function of osteosarcoma cell in a dose- and time-dependent manners, cisplatin may act as a efficient drug to cure osteosarcoma desease, which may be related to NOD1 and NOD2 signal pathway. Key words: Osteosarcoma; Tumor cells, cultured; Cisplatin; Polymerase chain reaction; Nucleotides; Adaptor proteins, signal transducing; Drug fvaluation