Prostaglandin and hydroxyeicosatetraenoic acid synthesis by human mesenchymal tumors

The metabolism of arachidonic acid was investigated by radioimmunoassay and chromatographic techniques in 5 sarcomas and one embryonal carcinoma of human origin maintained as transplantable tumors in nude mice. The results obtained indicate that: (1) the absolute quantities of arachidonic acid metabolites produced by a given tumor varied between experiments but the overall distribution pattern of these products, in general, remained constant from passage to passage; (2) each tumor showed a different arachidonic acid metabolite profile in quality and quantity; (3) 2 sarcomas of the same histological type could be clearly distinguished by their arachidonic acid metabolites; (4) the predominant product in all tumors was 12-HETE3 or 15-HETE, whereas thromboxane A2 was synthesized in low quantities by all tumors; (5) PGF2α was synthesized at the highest rate by an alveolar rhabdomyosarcoma; (6) PGE2 synthesis was highest in a malignant fibrous histiocytoma; and (7) total prostaglandin synthesis was low in the chondrosarcoma and synovial-cell sarcomas. All results reported in this study are for the complete tumor which includes both neoplastic and stromal cells. The role that these products play in the biological behavior of mesenchymal tumor cells and normal tissues of the host remains to be determined.