Effect of interleukin 2 on urinary excretion of degradation products of prostacyclin and thromboxane A2 in patients with ovarian cancer.

We studied the effect of intraperitoneal recombinant interleukin 2 (rIL-2) on the production of prostacyclin (PGI2) and thromboxane A2 (TxA2) in six patients with metastatic ovarian malignancy. Time-span urine samples collected before and after 17 intraperitoneal instillations of IL-2 (6 x 10(5) IU m-2) were assessed for 2,3-dinor-6-keto-prostaglandin F1 alpha (dinor-6-keto; a metabolite reflecting the in vivo product of PGI2) and 2,3-dinor-thromboxane B2 (dinor-TxB2; a metabolite reflecting the production of TxA2). Analysis was by high-pressure liquid chromatography, followed by radioimmunoassay. Recombinant IL-2 administration was accompanied by a significant rise (85%; P < 0.02) in the output of dinor-6-keto within the first 2 h, and this elevation persisted for up to 6 h. Moreover, output of dinor-TxB2 also rose; this rise (30%) was significant (P < 0.02) 6 h after the instillation. These effects may, in some yet unknown manner, prove significant in the anti-cancer action of rIL-2.