TGFB1 and neoplasm: Increasing numbers of circulating neutrophils have been found in various cancer types.31 In 2009, Fridlender et al.32 first demonstrated that increased neutrophils have two polarization states, N1 and N2, which play different roles in tumor progression in mice model bearing subcutaneous mesothelioma tumors with the treatment of transforming growth factor (TGF)-β inhibitor.