Secretion of basic fibroblast growth factor (bFGF) by marrow mononuclear cells (MNCs) as well as tumor and nontumor cells.

Basic FGF concentrations were determined in supernatants of marrow MNCs from control subjects (n = 4), marrow MNCs from patients with multiple myeloma (MM; n = 18), and of the corresponding sorted tumor and nontumor cell fractions of the MM marrows after 72 hours of culture. Basic FGF concentrations were corrected for 10⁶cells. Data are presented as medians and interquartile ranges. The Mann-Whitney rank sum test was used to identify differences between control MNCs and MM-MNCs (P = .02) and between tumor and nontumor cells (P < .0001).