Relations between sex hormones, sex hormone binding globulin, insulin-like growth factor-I and insulin-like growth factor binding protein-1 in post-menopausal breast cancer patients.
OBJECTIVE
Oestrogens, androgens and anti-endocrine drugs such as tamoxifen and aminoglutethimide influence plasma insulin-like growth factor-I (IGF-I). IGF-I, in turn, has been found to stimulate the peripheral aromatase in vitro. The aim of this study was to examine relations between sex hormones, IGF-I and insulin-like growth factor binding protein-1 (IGFBP-1) in post-menopausal women with breast cancer.


METHODS
To measure plasma sex steroids, sex hormone binding globulin (SHBG), IGF-I, IGFBP-1, insulin and urinary oestrogen metabolites in post-menopausal women with breast cancer not receiving any endocrine therapy.


METHODS
Thirty-two patients had fasting blood samples obtained between 0800 and 1000 h. A sub-group of 10 patients had 24-hour urine oestrogen metabolites determined.


METHODS
Plasma steroids and proteins were measured by radioimmunoassays. Urinary oestrogens were measured by GC-MS.


RESULTS
SHBG correlated negatively with plasma androstenedione (P < 0.001), insulin (P < 0.001), IGF-I, height and plasma oestrone sulphate (P < 0.025 for all), but positively with plasma IGFBP-1 (P < 0.025). IGFBP-1 correlated negatively with IGF-I (P < 0.001) and the testosterone/SHBG ratio (P < 0.05). Neither IGF-I nor IGFBP-1 correlated with any of the plasma or urinary sex hormones or with the oestrone/androstenedione and oestradiol/testosterone ratios. Multivariate analysis revealed plasma SHBG to correlate positively with IGFBP-1 (P = 0.029) and negatively with insulin (P = 0.031). Plasma IGFBP-1 correlated negatively with IGF-I (P < 0.0001) but not with insulin.


CONCLUSIONS
Our results do not suggest any influence of plasma sex steroids in physiological concentrations on IGF-I or IGFBP-1 in post-menopausal breast cancer patients, nor do they indicate IGF-I at physiological concentrations influences the ratios between plasma oestrogens and their androgen precursors.
Lønning
P E
PE
Department of Oncology, Haukeland University Hospital, Bergen, Norway.
Helle
S I
SI
Johannessen
D C
DC
Adlercreutz
H
H
Lien
E A
EA
Tally
M
M
Ekse
D
D
Fotsis
T
T
Anker
G B
GB
Hall
K
K
D000368:Aged; D000735:Androstenedione / Q000097:blood; D001943:Breast Neoplasms / Q000097:blood*; D002352:Carrier Proteins / Q000378:metabolism*; D004958:Estradiol / Q000097:blood; D004967:Estrogens / Q000652:urine; D004970:Estrone / Q000097:blood; D005260:Female; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006801:Humans; D018970:Insulin-Like Growth Factor Binding Protein 1; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008875:Middle Aged; D017698:Postmenopause / Q000097:blood; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism*; D013739:Testosterone / Q000097:blood; D013997:Time Factors
D002352:Carrier Proteins; D004967:Estrogens; D012739:Gonadal Steroid Hormones; D018970:Insulin-Like Growth Factor Binding Protein 1; D012738:Sex Hormone-Binding Globulin; D004970:Estrone; D013739:Testosterone; D000735:Androstenedione; D004958:Estradiol; D007334:Insulin-Like Growth Factor I