The expression of
fibroblast growth factors (
FGF1 and
FGF2) and their receptors has been reported in a variety of human
neoplasms, including haematological
neoplasia.
Fibroblast growth factors can promote tumour growth directly, or indirectly through promoting the growth of vessels. In the present study, we evaluated the expression of
FGF1 and
FGF2 as well as
FGF receptors 1-4 (FGFR1-FGFR4) in 39 cases of
Hodgkin's lymphoma, including all subtypes, as well as
Hodgkin's lymphoma cell lines.
FGF1 and
FGF2 and their receptors FGFR2-FGFR4, but not FGFR1, were found to be expressed by the malignant cells in the majority of cases. Interestingly, only FGFR3, but none of the FGFs or the other FGFRs, was expressed by the
Hodgkin's lymphoma cell lines. This indicates that only FGFR3 is constitutively expressed by
Hodgkin's lymphoma cells, whereas FGFs and the other FGFRs are induced in vivo. Culture of the Hodgkin's cell lines under conditions of hypoxic stress could induce
vascular endothelial growth factor (
VEGF) but not FGF expression. FGFs, in contrast to
VEGF, might be expressed in response to paracrine stimuli. In situ hybridization did not reveal FGFR3 gene amplification or translocation as the cause of constitutive FGFR3 expression, as has been shown in a subset of
multiple myeloma. FGFR3 might be expressed as part of the Hodgkin's cell phenotype. The demonstration of widespread expression of FGFs and some of their receptors in
Hodgkin's lymphoma suggests that FGFs are important for sustaining growth of the
lymphoma and suggests that anti-FGF
antibodies could be used as an adjuvant treatment.