TGFBR3 and neurofibromatosis type 1: Compared with normal controls, the protein levels of AMPD3 and TGFBR3 in NF1 patients were significantly elevated and reduced, respectively, in response to restored neurofibromin expression, suggesting that AMPD3 and TGFBR3 could serve as candidate biomarkers for evaluating the effectiveness of a PTC suppressor drug in NF1.