IL17A and neoplasm: There are different reports about the influence of IL-17 on tumour progression, some depict a positive influence of Th17 on tumour proliferation (Benchetrit et al, 2002; Numasaki et al, 2005) and angiogenesis, whereas others describe a inhibitory influence on tumour growth (Nam et al, 2008; Kryczek et al, 2009).