Abstract

The p53 gene is believed to play an important role through the mutation and overexpression in the progression of various human malignant tumors. The type IV collagenase (matrix metalloproteinase: MMP-2) initiates the degradation of the extracellular matrix, and consequently may play a role in the tumor invasion and metastasis. To investigate the correlation between clinicopathologic features of the colorectal adenocarcinomas and benign tumors and expression of p53 and MMP-2 proteins, we performed an immunohistochemical study on 40 colorectal adenocarcinomas, 20 adenomas and 20 hyperplastic polyps by using the antibodies to p53 and MMP-2 proteins. The positive expression rate of the p53 protein in adenocarcinomas was 62.5% and significantly higher than in benign tumors. The positive expression rate of the MMP-2 protein was 47.5% in adenocarcinomas, but there was no expression of MMP-2 protein in benign tumors. The difference in p53 and MMP-2 expression rates between malignant and non-malignant tumors was statistically significant. The positive expression rate of p53 protein in the non-metastatic and metastatic adenocarcinomas was 59.1 and 66.7%, respectively. The positive expression rate of MMP-2 protein in the non-metastatic and metastatic adencarcinomas was 45.5 and 50.0%, respectively. The correlation between several clinicopathologic features and expression of p53 and MMP-2 protein was not statistically significant, but the rate of positive MMP-2 immunoreactivity showed a statistically significant difference between Astler-Coller stage B1 C1 group and B2 C2 group of adenocarcinoma (p=0.0431). We concluded that the expression of p53 and MMP-2 protein contributes to the cancer development and MMP-2 may play a certain role in the invasiveness of the colorectal tumor. p53 and MMP-2 protein expression is not correlated with lymph node metastasis.

• Keywords: Colorectal adenocarcinoma;p53;MMP-2;Tumor invasion;Metastasis