TGFB1 and glioblastoma: Besides looking into patient genetics, TGF-β biomarkers include circulating levels of TGFβ, levels of P-SMAD2 levels in the peripheral blood mononuclear cells (PMNCs), and USP15 in glioblastoma breast and ovarian cancer (Akhurst and Hata, 2012; Eichhorn et al., 2012).