We examined the expression of both DRAK2 and COX-2 in a bank of colorectal tumour samples using total RNA extracted from tumour and normal mucosa sampled from the freshly resected tumours of 10 patients with CRC (not taking aspirin or NSAIDs). The levels of COX-2 transcript (normalised to 18S rRNA) were elevated in the majority of tumour samples relative to normal mucosa ( Figure 3B , mean 2.4-fold increase, P ¼ 0.006). DRAK2 expression showed an opposite pattern, with relative suppression of DRAK2 expression in tumour compared to normal from the same patient ( Figure 3A , mean decrease approximately 50%, P ¼ 0.003). A negative correlation between the ratio of DRAK2 and COX-2 expression (in tumour relative to normal) was noted ( Figure 3C , R ¼ À0.68, R 2 ¼ 0.46, P ¼ 0.03) reflecting an inverse relationship between the tumour/normal differences for the two genes across the patients sampled.