Fibroblast growth factor 2 in breast cancer: occurrence and prognostic significance

This paper examines the expression of fibroblast growth factor 2 (FGF-2) in the malignant human breast. Semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was used to assess the level of expression of FGF-2 in a series of 51 patients clinically followed up for a median of 84 months (Luqmani et al, 1992). Immunohistochemistry and Western blotting were used to show that the level of FGF-2 in breast tissues correlated with the amount of FGF-2 mRNA. FGF-2 was present in both malignant and non-malignant breast, although less was expressed in malignant tissues as determined by all three methods. Immunohistochemistry on frozen sections of breast tissue showed expression of FGF-2 in myoepithelial and epithelial cells in non-malignant samples and generally lower or undetectable levels of staining in malignant epithelial cells. The results obtained by immunohistochemistry correlated well with RT-PCR data showing similar levels of FGF-2 and FGF-2 mRNA expression in samples. No correlation was found between FGF-2 mRNA expression and T stage, nodal status or oestrogen receptor status. However, Kaplan-Meier survival plots show that higher levels of FGF-2 are associated with improved overall and disease-free survival. We suggest that FGF-2 expression may have value as a prognostic indicator in breast cancer.