Fig. 5.

COX inhibition reduces PGE₂ levels and reduces tumor growth in vivo. Nude mice were inoculated with SK-N-AS neuroblastoma cells harboring an 11q-deletion and were treated with diclofenac (250 mg/L drinking water) for nine consecutive days. (A) Tumor volumes were measured each day, and a significant difference between diclofenac-treated and control mice was seen on day 8 (P = 0.01) and day 9 (P = 0.008). (B) PGE₂ was measured in the tumors using solid-phase extraction and LC-MS/MS analysis. There was a significant decrease in PGE₂ in tumors from diclofenac-treated mice compared with control mice (P = 0.04). Bars represent median values.