Relationship between the expression of the extracellular matrix genes SPARC, SPP1, FN1, ITGA5 and ITGAV and clinicopathological parameters of tumor progression and colorectal cancer dissemination.

OBJECTIVE: To evaluate the relationship between the expression of the extracellular matrix (ECM) genes SPARC, SPP1, FN1, ITGA5 and ITGAV and the histopathologic parameters of neoplastic progression and colorectal carcinoma (CRC) dissemination.

METHODS: A retrospective study was conducted in 114 patients with stage I-IV CRC who underwent primary tumor resection. Quantitative real-time PCR and immunohistochemistry (IHC) assays were performed in samples obtained from the primary tumors. The correlation between the expression of these markers and the expression of p53, Bcl-2, Ki67, epidermal growth factor receptor (EGFR) and vascular endothelial growth factor was assessed with the Spearman coefficient (r).

RESULTS: The ITGAV gene was found to be significantly amplified in tumors with positive perineural invasion (p = 0.028). Expression of the SPARC, SPP1, FN1, ITGA5 and ITGAV genes did not correlate with TNM staging. A direct relationship between ITGAV and EGFR expression (r = 0.774; p < 0.001) was observed by IHC.

CONCLUSIONS: ECM gene expression did not correlate with classical prognostic factors for CRC, but overexpression of the ITGAV gene and protein was correlated with an increased risk of perineural invasion. The relationship between ITGAV and EGFR expression suggests the possibility of crosstalk in this signal pathway.