TGFB1 and neoplasm: Moreover, N2 neutrophils can be switched back to a tumour-cytotoxic N1 polarity through inhibition of TGFβ (Fridlender et al, 2009), or following immunologic or cytokine activation (Kim et al, 2008), re-enabling their potential to limit tumour growth (Kim et al, 2008), which is likely to be of significant therapeutic relevance.