Elevated serum E-selectin in patients with liver metastases of colorectal cancer

E-selectin, an endothelial cell adhesion molecule, mediates the initial step of leucocyte adhesion to activated vascular endothelium. The soluble isoform of E-selectin promotes angiogenesis in rat cornea. In the present study, we investigated whether leucocyte adhesion and angiogenesis are also involved in tumour progression and metastasis of colorectal cancer. Therefore, we determined the level of circulating soluble E-selectin in serum samples of 38 patients with colorectal cancer; 20 patients with non-metastatic and 18 patients with metastatic disease. Median levels of soluble E-selectin were found to be significantly higher in metastatic tumour disease (88.7 ng/ml, range 25-203 ng/ml) than in healthy controls (34.9 ng/ml, range 15-59 ng/ml, P = 0.01), in patients with primary tumours or with local recurrences (39.5 ng/ml, range 22-100 ng/ml). Furthermore, there was no correlation with the serum level of C-reactive protein, fibrinogen or tumour necrosis factor alpha suggesting that the elevation of E-selectin is independent of inflammation in tumour patients. Therefore, we propose that elevated soluble E-selectin may reflect increased neovascularisation in metastatic tumour tissue.