Consistently, inhibition of COX-2 with either non-steroidal anti-inflammatory drugs (NSAIDs) or with specific COX-2 inhibitors (COXIBs) can reduce the mortality of several types of cancer (11) and can switch the immune response from a tumour-promoting profile to a tumour-destructive one, re-ordering the tumour microenvironment (12). Here, PTGS2 is linked to cancer.