Is tryptase a novel serum bio-marker predictive of radical surgery in colo-rectal cancer patients?

Abstract

e22104 Background: Data from experimental tumour models suggest that mast cells (MCs) accumulate near tumour cells before the onset of angiogenesis. Tryptase is a serin protease stored in mast cell granules that plays a role in tumour angiogenesis. Mast cells (MCs) can release tryptase following c-Kit receptor activation. Here we aims to assess tryptase serum levels in CRC patients before and after radical surgery resection and c-Kit expressing cells in primary tumour tissue. Methods: In this study patients with stage B and C CRC (according to Astler e Coller staging system) were selected. Samples of blood were taken from CRC patients between 7 and 9 a.m. 1 day before and 1 day after tumour surgical resection. Venous blood was dispensed into a tube for serum (Becton Dickinson Hemogard Vacutainer Systems, Plymouth, UK). Serum blood samples were centrifuged at 1,500g for 10 minutes and then aliquoted and frozen at -80 °C. Tryptase levels were measured using the UniCAP Tryptase Fluoroenzymeimmunoassay (Pharmacia,Uppsala, Sweden). In addition primary tissue section were immunostained with a primary anti c-Kit antibody (A4502; Dako, Glostrup, Denmark) by mean of immunohistochemistry. Results: Mean ± s.d. tryptase level pre-tumour surgical resection was 6.38 ± 4.49 μg/L, and mean ± s.d. tryptase level post tumour surgical resection was 5.11 ± 3.81 μg/L. A statistically significant difference between pre-tumour surgical resection and post-tumour surgical resection tryptase level concentrations was found: p=0.000 by t-test. A strong correlation between pre-tumour surgical tryptase level and c-Kit expressing cells was also found (r=0.81, p=0.000). Conclusions: This is the first report that analyzes the possible significance of serum tryptase levels changes in CRC patients who underwent radical surgical resection. Our results demonstrated higher serum tryptase levels CRC patients suggesting the release of tryptase from c-Kit expressing cells CRC tissue. We suggest that tryptase may play a role as a novel serum tumour bio-marker predictive of radical surgery in CRC patients. In this context tryptase inhibitors might be evaluated in adjuvant clinical trials as a new antiangiogenetic approach.