Increased intraplatelet and urinary transforming growth factor-beta in patients with multiple myeloma

The concentrations of transforming growth factor-beta (TGF-beta) in platelets, plasma and urine from 27 patients with multiple myeloma (MM) and from 22 normal controls were measured by sandwich enzyme-linked immunosorbent assay using a monoclonal antibody specific for human TGF-beta 1+2+3. A significantly increased intraplatelet TGF-beta (24.6 +/- 9.6 vs. 17.8 +/- 8.8 ng/10(5) platelets, p < 0.01) and urinary TGF-beta (1.4 +/- 0.8 vs 1.0 +/- 0.4 ng/mg Cr, p < 0.02) were observed in MM patients compared with normal controls. The mean platelet TGF-beta level in MM patients with osteolytic lesions was more increased than in those without osteolytic lesions (29.6 +/- 7.7 vs 18.4 +/- 8.2 ng/10(5) platelets, p < 0.001). In this study, we evaluated the possible role of TGF-beta in the pathogenesis of myeloma, especially in osteolytic lesions.