Differences in Expression of VEGF-A, VEGFR-1, VEGFR-2 and Microvessel Density in Colorectal Cancer with Liver Metastasis

ABSTRACT

BACKGROUND: Colorectal cancer (CRC) is one of the most common malignant neoplasms and is a leading cause of mortality worldwide. Metastasis to the liver is a frequent event in patients with CRC. An essential step in the metastatic cascade is angiogenesis. METHODS: This study included 45 patients who underwent a partial colectomy with hepatic resection for CRC with hepatic metastases. Immunohistochemistry was performed using vascular endothelial growth factor (VEGF)-A, VEGF receptor (VEGFR)-1, VEGFR-2, and CD34 antibodies to examine the relationship between CRC with liver metastases and angiogenesis. RESULTS: CRC showed significantly stronger expression of VEGF-A, VEGFR-1, and VEGFR-2 than liver metastases (p < 0.05). Microvessel density was also higher in CRC than in liver metastases (p < 0.05). CONCLUSIONS: Compared with previous studies, we found a higher expression of VEGF-A, VEGFR-1, VEGFR-2, and microvessel density in CRC than in liver metastases, which could be ascribed to a difference in vessel distribution and blood supply in each organ. Given its profuse blood supply and distinct cell populations, the liver might provide a rich milieu for tumor cell growth with less expression of angiogenesis-inducing agents.