Altered expression of metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 in cervical disc herniation patients.

The aim of the current study was to examine matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) expression in patients with cervical disc herniation (CDH). A total of 127 specimens from CDH patients undergoing posterior spinal surgery were obtained for the case group, which was divided into three subgroups: lateral protrusion (N = 102), median protrusion (N = 18), and paramedian protrusion (N = 7). Another 55 specimens from subjects who had cervical spine trauma and underwent spinal canal decompression were obtained for the control group. Routine hematoxylin and eosin staining was performed for pathological diagnosis. Immunohistochemical (IHC) analysis was used to determine MMP-2 and TIMP-2 expression. Under light microscopy, MMP-2-positive cells presented brown-yellow or dark brown staining in the cell membrane or cytoplasm. MMP-2 expression in the case group was significantly higher than that in controls (P 0.05). IHC results showed that TIMP-2 expression in cases was significantly lower than that in controls (P < 0.05). Spearman correlation analysis indicated that MMP2 was negatively correlated with TIMP-2 expression (r = -0.418, P < 0.001). In conclusion, MMP-2 expression increased, whereas TIMP2 expression decreased in CDH patients, suggesting that MMP-2 and TIMP-2 expression may contribute to CDH development.