Nup88 mRNA overexpression in colorectal cancers and relationship with p53.

Objectives: We measured nucleoporin 88 (Nup88) mRNA expression in primary colorectal cancers to investigate its relationship with clinicopathological features and p53.

Methods: The primary cancer tissues, adjacent noncancerous tissues and the proximal and distant margins of normal mucosa were collected from 73 colorectal cancer patients during surgery. Nup88 mRNA expression was measured on these fresh specimens and on colon cell lines HCT-116^{p53 + / + } and HCT-116^{p53 - / - } by RT-PCR while p53 mRNA and β-actin as controls. Nup88 and p53 protein expression were then immunohistochemistrically examined in other 25 colorectal cancers specimens paraffin embedded and formalin fixed.

Results: Nup88 expression was higher in primary cancer tissues than in adjacent noncancerous tissues, and in the proximal and distant margins of normal mucosa. Overexpression of Nup88 mRNA was statistically associated with TNM stage (P=0.044), lymphatic metastasis (P=0.022), and cancer location (P=0.036), while not related to gender, age of patients and histological type, infiltration depth, and differentiation of cancers. The expression of Nup88 mRNA in the HCT-116^{p53 - / - } cell line was not significantly different from expression in the HCT-116^{p53 + / +}cell line. And there was no correlation between Nup88 and p53 protein expression (r=0.632, P=0.368).

Conclusions: Nup88 mRNA was overexpressed in colorectal cancers and the overexpression was associated with cancer development and aggressiveness. Nup88 might be regard as essential contributor to nodal metastagenicity of colorectal cancer.