Increased serum levels of basic fibroblast growth factor in lung cancer patients: relevance to response of therapy and prognosis.

Angiogenesis is controlled by inhibitors and angiogenic factors. Among these, basic fibroblast growth factor (bFGF) is closely involved in cancer proliferation and has been related to progression and prognosis of various cancers, including lung cancer. To evaluate the role of bFGF, we measured serum levels of bFGF from healthy controls (Ctrl) and 106 patients with lung cancer, including 31 adenocarcinomas (AD), 29 squamous cell carcinomas (SQ), and 46 small cell carcinomas (SCLC), by enzyme-linked immunosorbent assays. Moreover, we evaluated the relationship between serum levels of bFGF and clinical outcome. Serum levels of bFGF in AD, SQ, SCLC, and Ctrl were 7.6 (0.5-32.5) (median (range)), 7.4 (0.5-36.7), 7.1 (0.5-34.8) and 3.0 (1.5-6.0) pg/ml, respectively (P<0.05). Serum bFGF levels did not differ between clinical stages in non-small cell lung cancer (NSCLC; AD+SQ). In SCLC, we found a significant difference in serum levels of bFGF between chemotherapy (and/or radiotherapy) responders (complete response+partial response) and non-responders (no change+progressive disease) (9.2 (0.6-34.8), 4.4 (0.5-17.4) pg/ml, respectively (P=0.018)), whereas there was no difference in NSCLC. Moreover, serum bFGF levels in SCLC patients had significant impact in prognosis by uni and multivariate analysis (P=0.014, 0.018, respectively). We concluded that bFGF has an important role in the prognosis of patients with SCLC.