Modulation of oestrogen excretion profiles by adjuvant chemotherapy in pre- and postmenopausal breast cancer

Endocrine profile in breast cancer patients receiving chemotherapy

Cyclophosphamide and other alkylating agents suppress ovarian function in pre-menopausal women. However, endocrine details remain unknown regarding the influence of patients' age and obesity on CMF-induced hormonal changes. We studied changes in endocrine profile due to chemotherapy (CMF) in 70 pre-menopausal patients with axillary node positive, stage II and/or III breast carcinoma. Plasma levels of estrone (E1), estradiol (E2), androstenedione (A2), luteinizing hormone (LH), and prolactin (PRL) were determined on day 1 and 8 of each chemocycle for 12 cycles. After receiving therapy, 23% of the women continued to have regular menstrual cycles (non-amenorrheic group). In the remaining 77%, ovarian function was suppressed, as evidenced by the onset of amenorrhea within 0-11 months (amenorrheic group). The mean time to amenorrhea was 2.83 +/- 0.33 months (SE). The time required to develop amenorrhea inversely correlated to the patient's age. Both incidence of amenorrhea and time to amenorrhea remained unaffected by either patient's obesity or the timing of chemotherapy initiation in relation to menstrual cycle phase (progestational, follicular). Plasma hormone levels fluctuated widely in both groups during the first three chemocycles. During chemocycle months 4 to 10, in the amenorrheic group, plasma E1, E2, and P declined to their baseline levels with a concomitant rise in LH levels. At this time, E1, E2, and P levels were significantly lower in amenorrheics, despite menstrual cycle associated fluctuations in the non-amenorrheic group. Estrogens (E1 and E2) gradually declined further following the onset of amenorrhea in subsequent months. Further data analysis suggests that host age or obesity did not influence CMF-induced changes in the plasma endocrine profile.

Estrone conversion rates by human endometrial cancer cell lines

Studies on estrone metabolism by long term human endometrial cancer HEC-1A and Ishikawa cell lines are reported. These cell lines grow well in epithelial mono or plurilayer form, as previously reported. Ishikawa cells appear to be estrogen responsive whereas HEC-1A appear non responsive. In our experience Ishikawa cells show high affinity--low capacity estrogen binding sites in both soluble and nuclear fractions of the same range of ZR 75-1 and of MCF7, but HEC-1A cytosols gave Kd values in the order of 10(-8)-10(-9). These values are probably more representative of estrogen receptors of low affinity-high capacity (site II) and this is in agreement with previous results regarding their poor response to estrogens. These two different endometrial cancer cell lines exhibit at the same time, common and quite dissimilar metabolic patterns of estrogens. In fact, metabolic conversion studies carried out after 24th incubation at not far from physiological concentrations by using high pressure liquid chromatography in reverse phase mode plus "on line" radioactive detection showed: Both these well established cell lines are fast growing in culture with sufficient morphological or biochemical stability, at least during a limited number of passages and appear a useful material for studies on steroid metabolism. In both, estradiol (E2) and estrone (E1) were most part of converted products (more than 95%); negligible amounts of other radio-metabolites were observed. Quite different conversion rates of E1 to E2 have been shown by HEC-1A cells (6 times or more), with respect to Ishikawa.