Technique for the primary culture of human breast cancer cells and measurement of their prostaglandin secretion.

1. A method is described for the primary culture of human breast tumour cells on feeder layers of the STO mouse embryo fibroblast cell line. 2. The secretion of the prostaglandins E2 and F2 alpha from the cells was measured and the results indicate that the secretion of both prostaglandins was dependent on oestrogen-receptor status, with cells from oestrogen-receptor-positive tumours secreting significantly more prostaglandin than cells from oestrogen-receptor-negative tumours. 3. Prostaglandin E2, but not prostaglandin F2 alpha, secretion was also significantly greater from cells of tumours from postmenopausal women than from cells of tumours from premenopausal women. Small (< 3 cm) tumours secreted significantly more prostaglandin than large (> 3 cm) tumours, and increased levels of prostaglandin were secreted with advancing clinical stage (T1-T4). 4. Additional evidence for increased prostaglandin metabolism in oestrogen-receptor-positive tumours compared with oestrogen-receptor-negative tumours was obtained from studies on the uptake of [14C]arachidonic acid from the cultures. Significantly more labelled arachidonic acid was incorporated into cells from oestrogen-receptor-positive tumours compared with oestrogen-receptor-negative tumours, with the subsequent release of more prostaglandin in response to various stimuli.