**4.1 Overview**

Both TLR3 and TLR4 signalling produce a pro-inflammatory response including chemokines and it has previously been shown that the pro-inflammatory response may contribute to tumorigenesis (Kelly, 2006). Chemokines and cytokines are markers of inflammation which normally recruit leucocytes and aid in blood vessel remodelling. Pathophysiological roles for chemokines include acting as autocrine growth factors, disruption of basement membranes, increasing motility and tumour invasion (Rollins, 2006; Balkwill 2004).
