Since this A8301- and A7701-sensitive fraction of baseline FAP protein and FAP enzymatic activity could be due to upregulation via autocrine TGFbeta-1 signaling, we investigated the secretion of endogenous TGFbeta-1 in U87 and U251 glioma cells and in human brain vascular pericytes (HBVP). This evidence concerns the gene FAP and glioma.