Prostaglandin E2 concentrations in naturally occurring canine cancer

The purpose of this study was to determine the PGE(2) concentration in naturally-occurring cancer in pet dogs and in canine cancer cell lines in order to identity specific types of canine cancer with high PGE(2) production which could serve as preclinical models to evaluate anticancer strategies targeting PGE(2). PGE(2) concentrations were measured by enzyme immunoassay in canine melanoma, soft tissue sarcoma, transitional cell carcinoma, osteosarcoma, and prostatic carcinoma cell lines; in 80 canine tumor tissue samples including oral melanoma (MEL), oral squamous cell carcinoma (SCC), transitional cell carcinoma of the urinary bladder (TCC), lymphoma (LSA), mammary carcinoma (MCA), osteosarcoma (OSA), prostatic carcinoma (PCA); and in corresponding normal organ tissues. High concentrations of PGE(2) (range 400-3300 pg/10(4) cells) were present in cell culture medium from the transitional cell carcinoma, prostatic carcinoma, and osteosarcoma cell lines. PGE(2) concentrations in tu mor tissues were elevated (tumor PGE(2) concentration > mean+ 2x sd PGE(2) concentration of normal organ tissue) in 21/22 TCC, 5/6 PCA, 7/10 SCC, 5/10 MEL, 3/8 MCA, 4/15 OSA, and 0/9 LSA. Results of this study will help guide future investigations of anticancer therapies that target cyclooxygenase and PGE(2). (C) 2001 Harcourt Publishers Ltd.