TLR4 and neoplasm: Through FadA-E-cadherin binding on Toll-like receptor 4 (TLR4), Fn can accelerate colonic carcinogenesis mainly in the presence of pre-existing genetic alterations, while Fap2-TIGIT binding can promote tumour survival by smouldering anti-tumour immunity (Gur et al., 2015; Borroni et al., 2019) (Figure 1).