COX2 and HLA immunohistochemical (IHC) staining in colorectal tumour samples from patients participating in the ASCOLT clinical trial of adjuvant aspirin therapy.

Abstract

695 Background: ASCOLT is an international Phase III randomized control trial (NCT00565708) investigating the impact of adjuvant aspirin on recurrence and survival after curative resection of colorectal cancer (CRC). Retrospective data suggest that COX2 and HLA Class 1 antigen expression may predict for aspirin benefit (Reimers MS, JAMA internal medicine, 2014;174(5):732-739; and Chan AT, JAMA, 2009;302(6):649-658.) Translational studies aim to confirm putative biomarkers of aspirin sensitivity in this prospective trial. This study reports the IHC assessment of COX2 and HLA in representative samples. Methods: FFPE slides from consenting Australian patients were stained with COX2 and HLA Cla..