Effect of serum amyloid A on invasion,migration and MAPK signaling pathway in osteosarcoma cells

AIM: To investigate the effect of silencing of serum amyloid A (SAA) on the viability, apoptosis, migration and mitogen-activated protein kinase (MAPK) signaling pathway in osteosarcoma U2OS cells. METHODS: Small interfering RNA (siRNA) targeting SAA was transfected into U2OS cells to silence the expression of SAA gene. The U2OS cells were divided into blank control group, negative control group, and experimental group. The cells in negative control group and experimental group were transfected into negative control siRNA and SAA-siRNA, respectively. The cells in blank control group were without any treatment. The viability of the cells was measured by MTT assay and the apoptotic rate was analyzed by flow cytometry with Annexin V-FITC/PI double staining. The migration and invasion abilities of the cells were detected by Transwell chamber assay. The protein levels of SAA, phosphorylated p38 MAPK (p-p38 MAPK) and phosphorylated c-Jun N-terminal kinase (p-JNK) in the cells were determined by Western blot. RESULTS: The protein expression of SAA in SAA-siRNA group was significantly lower than that in blank control group (P<0.05). Compared with blank control group, the cell viability in SAA-siRNA group was significantly decreased (P<0.05), the apoptotic rate was significantly increased (P<0.05), and the invasion and migration abilities were significantly decreased (P<0.05). The protein levels of p-p38 MAPK and p-JNK in SAA-siRNA group were significantly lower than those in blank control group (P<0.05), and no significant difference of total JNK and p38 protein levels was observed. CONCLUSION: Silencing of SAA expression inhibits the viability of osteosarcoma cells, induces apoptosis and decreases the migration of osteosarcoma cells, which may be related to the activation of MAPK signaling pathway.