TGFB1 and neoplasm: It has previously been demonstrated that Siglec-15 recognizes the tumoral the sialyl-Tn antigen and transduces a signal for enhanced transforming growth factor-β (TGF-β) secretion in tumor-associated macrophages and suggests that the expression of Siglec-15 on macrophages may contribute to tumor progression by the TGF-β-mediated modulation of the intratumoral microenvironment8.