Serum syndecan-1, basic fibroblast growth factor and osteoprotegerin in myeloma patients at diagnosis and during the course of the disease

Neovascularisation and bone resorption are related to myeloma disease activity.

Objectives: To investigate the possible prognostic importance of serum syndecan-1, basic fibroblast growth factor (bFGF) and osteoprotegerin (OPG) levels, the relationship between them, with parameters of disease activity and the effect of treatment on their levels.

Patients and Methods: Twenty-seven patients were studied from diagnosis and an additional five from remission, for a median follow-up of 40 months. Twenty-three patients received chemotherapy plus bisphosphonates and nine only bisphosphonates. Sera from 11 healthy individuals (HI) were used as controls. Cytokines were determined by commercially available enzyme-linked immunosorbent assays (ELISA) kits.

Results: In HI, median syndecan-1 was 40 ng/mL (28–75), bFGF 8 pg/mL (7–30), OPG 35 pg/mL (4–100). Pretreatment median serum syndecan-1 was 177.5 ng/mL (34–3500), bFGF 11.5 pg/mL (8–65) and OPG 100 pg/mL (4–1000). Pretreatment syndecan-1, bFGF and OPG serum levels were increased in patients compared with HI (P = 0.001, 0.03 and 0.01, respectively). Syndecan-1 and bFGF levels were correlated with stage (P = 0.004 and 0.03, respectively). Both syndecan-1 and OPG levels were correlated with β₂M (P = 0.04 and 0.01, respectively). Patients with elevated syndecan-1 and bFGF serum levels had shorter survival than patients with normal levels (P = 0.01 and 0.05, respectively). After chemotherapy syndecan-1 and OPG levels were found to be decreased in responders and syndecan-1 level was reduced in patients receiving bisphosphonates alone.

Conclusions: Pretreatment syndecan-1, bFGF and OPG levels were found to be increased at diagnosis. Syndecan-1 and OPG fluctuated according to MM activity. Elevated serum syndecan-1 and bFGF levels predicted short survival.