The expression of PDGFA, PDGFB, TGFB1 and TGFB2 in pituitary tumor tissue was respectively 3.5 x104, 2.0 x 104, 1.3 x 105 and 6.6 x 103 copies/μg total RNA (Figure 5A). This evidence concerns the gene TGFB1 and pituitary tumor.