Distribution and prognostic value of the fibroblast growth factor-2 low-affinity binding sites in human breast cancer

We performed a competitive binding study with I-125-labelled FGF (fibroblas t growth factor) -2 and unlabelled FGF-2 in an unselected series of two hun dred and thirty human primary breast cancers. One hundred and ninety-two br east cancer biopsies possessed FGF-2 low-affinity binding sites (FGF-2 LABS ). The median dissociation constant was 2.4 nM (range, 1.03 -18) and the me dian concentration of membrane protein was 6187.5 fmol/mg (range, 831 -9000 0). FGF-2 LABS concentrations were positively correlated to the progesteron e receptor level. Cox univariate analyses showed that the FGF-2 LABS (great er than or equal to upper quartile) was associated to a longer overall surv ival (p = 0.05; RR = 0.042); node involvement, estrogen receptor progestero ne receptor and histoprognostic grading were also prognostic. In Cox multiv ariate analyses, only the progesterone receptor, estrogen receptor, node in volvement and FGF-2 LABS were prognostic factors; the FGF-2 LABS were assoc iated with a longer overall survival (p = 0.033; RR = 0.068). The present s tudy showed that FGF-2 LABS have only a limited role as a prognostic factor in breast cancer.