Prostaglandin synthesis by squamous carcinoma cells of head and neck, and its inhibition by non-steroidal anti-inflammatory drugs.

The purpose of this study was to determine the nature and amounts of prostaglandins (PGs) produced by squamous carcinoma cells (SCC) and the sensitivity of these cells to non-steroidal anti-inflammatory drugs. SCC of four lines of the tongue and one line of facial epidermis of humans were incubated in phosphate buffer solution with 14C-arachidonic acid (AA). Radioactive metabolites in aqueous methanol were chromatographed on Sep-Pack C18 cartridges, separated and quantitated by means of TLC, autoradiography, and liquid scintillation counting. The results showed that cyclooxygenase products, PGs, were the major products formed by all cell lines, and PGE2 was predominant among the PGs detected. Two radioactive bands corresponding to PGF2 alpha and three unseparated standards of PGA2, 15-keto-PGE2, and 13,14-dihydro-15-keto-PGE2 were detected in lesser amounts. Very small amounts of the lipoxygenase products 12- and 15-HETE were found. The concentrations of indomethacin, ibuprofen and aspirin required to inhibit 50% of PGE2 synthesis (IC50) by SCC lines were .008-.080, .080-6.4 and 32-88 microM, respectively.