Effects of S100 calcium-binding protein A8 (S100A8) and S100 calcium-binding protein A9 (S100A9) on matrix metalloproteinase (MMP) expression in nasopharyngeal carcinoma CNE-2 cells

BACKGROUND: Studies have shown that S100A8 and S100A9 are highly expressed in a variety of tumors, including NPC, and are associated with tumor invasion and migration. MMPs are associated with the invasion and migration of tumor cells. To further investigate the mechanism by which S100A8 and S100A9 affect the invasion and migration of NPC cells, the present study examined the effects of S100A8 and S100A9 on MMPs in NPC CNE-2 cells. METHODS: Recombinant pEGFP-N1-S100A8 and recombinant pEGFP-N1-S100A9 overexpression vectors and S100A8 and S100A9 RNA interference (RNAi) vectors were constructed and transfected into NPC CNE-2 cells. The transfection efficiency in each group of cells was assessed, and the gene and protein expression of MMP7, MMP9 and MMP12 were determined. RESULTS: The transfection efficiency was approximately 60–70%. Compared with those in the control group, the expression levels of MMP7, MMP9 and MMP12 in the S100A8 and S100A9 overexpression groups was significantly higher (P<0.05), and the expression levels of MMP7, MMP9 and MMP12 in the S100A8-RNAi and S100A9-RNAi groups were significantly lower (P<0.05). The number of cells in S100A8 overexpression group and S100A9 overexpression group at 24, 48 and 72 h was higher than that in RNAi group, RNAi control group, overexpression control group and normal control group, with statistical significance; The cell doubling time in S100A8 and S100A9 overexpression group was significantly shorter than that in RNAi control group, overexpression control group and normal control group, with statistical significance. CONCLUSIONS: High S100A8 and S100A9 expression may promote the expression of MMP7, MMP9 and MMP12, which are related to the invasion and metastasis of NPC cells.