Gene expression and tissue concentrations of IGF-I in human myometrium and fibroids under different hormonal conditions.
The expression of insulin-like growth factor-I (IGF-I) was measured at the mRNA and protein level in myometrium and fibroids from women with and without preoperative treatment with a gonadotrophin-releasing hormone (GnRH) agonist for 3 months, from post-menopausal women, from pregnant women and in myometrium from women without fibroid disease. Women with menstrual periods were classified according to the phase of the cycle. In tissues from non-treated premenopausal women, IGF-I mRNA expression was significantly higher in fibroids than in myometrium, with no differences related to phase of the menstrual cycle. In post-menopausal women and in GnRH agonist-treated women responding to treatment, similar mRNA expression was seen in myometrium and fibroids but the concentrations were lower than in untreated premenopausal women. The IGF-I mRNA value in fibroids from pregnant women was higher than in any other group and myometrium from pregnant women exhibited higher mRNA expression than myometrium from non-treated premenopausal women. The IGF-I protein was more abundant in fibroids than in myometrium of non-treated premenopausal and of pregnant women and in both tissues the concentration was significantly higher in the group of pregnant women. The IGF-I protein concentrations in fibroids and myometrium from GnRH agonist-treated and post-menopausal women were similar to those from premenopausal non-treated women. High sex steroid concentrations in pregnant and non-pregnant women of fertile age seem to be associated with a higher expression of IGF-I in fibroids than in myometrium, suggesting that IGF-I contributes to the selective growth advantage of these tumours.
Englund
K
K
Department of Obstetrics and Gynecology, Huddinge University Hospital, Karolinska Institute, S-141 86 Huddinge, Stockholm, Sweden.
Lindblom
B
B
Carlström
K
K
Gustavsson
I
I
Sjöblom
P
P
Blanck
A
A
D000328:Adult; D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000494:pharmacology; D004958:Estradiol / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D015870:Gene Expression; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists; D017273:Goserelin / Q000494:pharmacology; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000235:genetics / Q000378:metabolism*; D007889:Leiomyoma / Q000235:genetics / Q000378:metabolism*; D008593:Menopause; D008597:Menstrual Cycle; D008875:Middle Aged; D009215:Myometrium / Q000378:metabolism*; D011247:Pregnancy; D011374:Progesterone / Q000097:blood; D012333:RNA, Messenger / Q000378:metabolism
D018931:Antineoplastic Agents, Hormonal; D012333:RNA, Messenger; D017273:Goserelin; D007987:Gonadotropin-Releasing Hormone; D011374:Progesterone; D004958:Estradiol; D007334:Insulin-Like Growth Factor I; D005640:Follicle Stimulating Hormone