Expression and significance of vascular endothelial growth factor and p53 in degenerated intervertebral disc tissues

Abstract

Objective To investigate the mechanism of expression and significance of vascular endothelial growth factor and p53 in degenerate intervertebral disc tissue. Methods The nucleus pulposus tissues of 56 patients with lumbar disc herniation were collected as degeneration group and 20 patients with lumbar burst fracture as normal group. The nucleus pulposus was divided into five grades according to Thompson classification. We evaluated the expression of vascular endothelial growth factor and p53 in 56 pathological sections of intervertebral disc tissues with immunohistochemical method. Then, we recorded and graded positive staining rates of vascular endothelial growth factor and p53, respectively. T-test was used to compare the positive rate of vascular endothelial growth factor and p53 in degenerative group and normal group. Spearman grade correlation analysis was used to analyze the correlation between the grade of intervertebral disc degeneration and the expression of vascular endothelial growth factor and p53. Results We found 38 cases (67.86%) with vascular infiltration of the degenerative group. The positive rates of vascular endothelial growth factor and p53 staining in degenerative group were 71.43% (40/56) and 60.71% (34/56), respectively. The total expression rate was 55.36% (31/56), and the difference was significant (P<0.05). There was no positive expression of vascular endothelial growth factor and p53 in 20 normal intervertebral disc tissues in normal group. The positive rates of vascular endothelial growth factor and p53 staining were 84.21% (32/38) and 63.16% (24/38) in the degenerative disc tissues with vascular infiltration, and 44.44% (8/18) and 55.56% (10/18) in the degenerative disc tissues without vascular infiltration, respectively. The differences were statistically significant (P<0.05). The expression rates of vascular endothelial growth factor and p53 in vascular invasive tissues were significantly higher than those in non-invasive tissues. Degenerative grade of intervertebral disc was positively correlated with the expression of vascular endothelial growth factor and p53. Conclusion Vascular endothelial growth factor and p53 gene are co-expressed in degenerated intervertebral disc tissue, which act on the formation and infiltration of new blood vessels and accelerate the degeneration of intervertebral disc tissue. Key words: Vascular endothelial growth factor; P53; Degenerated intervertebral disc tissues; Vascular infiltration