PAF-receptor antagonist, WEB2170, inhibits melanoma growth and in combination with chemotherapy improves the survival of melanoma-bearing mice. (A) B16F10 melanoma cells (5 × 105) were injected s.c. into C57BL/6 mice and tumours were measured daily with a caliper. Tumour volume was calculated by the formula: maximum diameter × (minimum diameter)2 × 0.52. WEB2170 (5 mg/Kg) was given i.p. 30 minutes before the tumour followed by daily injections for 12 days. DTIC (40 μg/animal) was injected i.p. every 3 days after tumour implantation. Data represent the mean ± SEM of tumour volume (n = 5). (B) The Kaplan-Mayer survival curve. For the survival experiments, WEB2170-treatment was given once a day and DTIC every 3 days for 35 days or until the animals died (n = 8-9). Statistical analyses were performed using the log rank test and differences were considered significant at p < 0.05. (*) p < 0.05 compared to PBS group.