Aminoglutethimide-induced hypercholesterolaemia

Aminoglutethimide in Advanced Breast Cancer

From July 1980 to June 1983, 61 postmenopausal women with progressive metastatic breast cancer were treated with aminoglutethimide, 250 mg 4 times daily, plus cortisone acetate, 25 mg twice daily. Of 51 evaluable patients, an objective remission was observed in 22 (43 %) (partial remission in 19, complete in 3), stable disease in 14 (27 %), and progressive disease in 15 (30 %). The median duration of response was 60 weeks (range 12 +; 94+). The response rate was higher when the dominant disease site was soft tissue (50 %) or bone (56 %) rather than viscera (29 %). Side effects were common but usually slight and transient. Somnolence (69 %), dizziness (41 %), nausea (35 %) and skin rash (27 %) were the most frequent. Serum levels of gamma-GT, alkaline phosphatase and total cholesterol rose during aminoglutethimide treatment, whereas levels of uric acid and indirect bilirubin decreased. Aminoglutethimide plus cortisone acetate appears to be an active and relatively safe treatment in advanced breast cancer and may be recommended as second-line endocrine treatment.

Variations in lipoproteins during aminoglutethimide therapy

Plasma lipids, apolipoproteins, and gamma-glutamyl-transpeptidase (GGT) were measured in 28 patients receiving aminoglutethimide (500 mg) and hydrocortisone (30 or 40 mg) for advanced breast cancer. A rise in cholesterol (CHOL), LDL-CHOL, apoprotein B, apoprotein CIII, and GGT was observed after 45 days. When the patients were divided in two groups according to lipid basal plasma levels, those with high CHOL and triglyceride did not experience any modification of lipid parameters (only GGT were elevated). Conversely normolipidaemic patients experienced an increase in CHOL, triglycerides, LDL-CHOL, apoproteins B and CIII, and GGT.

Inhibition of aromatase activity in the rat by aminoglutethimide and related compounds

Two compounds possessing aromatase inhibitory activity have been evaluated for their effects on oestradiol (E2) biosynthesis in the rat. These compounds, structurally related to aminoglutethimide (1), were administered intra-peritoneally at two dose levels to 10 week old female rats previously treated with pregnant mares' serum gonadotrophin (PMSG, 100 i.u. subcutaneously every other day for 9 days). Three hours after dosing, blood was collected and plasma oestradiol levels determined by RIA. Aminoglutethimide, 3-(4'-aminophenyl-3-ethylpyrrolidine-2,5-dione (2) and N-methyl-3-(4'-aminophenyl)-3-ethylpyrrolidine-2,5-dione (3) decreased E2 blood levels by 98, 97 and 82% of control levels respectively (n = 6) at a dose of 50 mg/kg. Similarly effective inhibition was also observed at a dose of 25 mg/kg (n = 4). Ovarian aromatase activity, assessed by incubating the homogenised ovaries of treated rats with tritium-labelled androstenedione (0.2 microM) or testosterone (1 microM), indicated that residual enzyme activity was reduced compared with controls. Aminoglutethimide, and the new pyrrolidinedione aromatase inhibitors 2 and 3, are therefore effective inhibitors of E2 biosynthesis in the rat with functioning ovarian activity.