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Aim: The aim of the present work was to assess the influence of estradiol administration mode on the plasma IGF-I, IGFBP-1, IGFBP-3 levels in postmenopausal women treated with norethisterone acetate., Material and Methods: 39 women were enrolled into the study Group A--14 women received transdermal 17beta-estradiol (Oesclim 50--Fournier-Solvay) combined with oral norethisterone 2.5 mg daily (Primolut-Nor--Schering), Group B--10 women on oral 2 mg 17beta-estradiol combined with oral 1 mg daily norethisterone (Kliogest--Novo-Nordisk). Control group (group C) consisted of 15 postmenopausal women who received no treatment. Basic plasma FSH, estradiol and total IGF-I, IGFBP-1 as well as IGFBP-3 levels were measured initially and at the 52nd week of the study., Results: The mean plasma FSH level was reduced and mean plasma estradiol level was increased in groups A and B during hormone therapy. Mean plasma levels of total IGF-I, IGFBP-1, IGFBP-3 as well as IGFBP-3/IGF-I ratio did not changed significantly during 52 weeks of observation in groups A, B and C. The comparison of plasma IGF-I, IGFBP-1, IGFBP-3 between groups at the initial visit and after 52 weeks showed the lowest concentration f IGBP-3 in group B. Other parameters showed no differences among the three groups., Conclusion: Mode of administration of estradiol did not influenced the plasma levels of IGF-I, IGFBP-1, IGFBP-3 in postmenopausal women treated with norethisterone acetate.

Objective: To compare the influence of low and normal endogenous estradiol concentration on circulating hGH, IGF-I and IGFBP-3 levels as well as on mutual correlations of these parameters., Patients: 45 women (age 30.7 ± 9.0 years, BMI 25.7 ± 8.0) divided into group A - 15 hypoestrogenic women and group B - 30 normoestrogenic controls. Neither of the women was menopausal nor hyperprolactinemic., Methods: Blood sample was taken at the standard conditions prior to the initiation of hormonal supplementation therapy in group A and at the day 3-5 of menstrual cycle in group B. Serum hGH, IGF-I, IGFBP-3, insulin, testosterone, sex hormone binding globulin (SHBG) dihydroepiandrosterone sulphate (DHEAS) and LH as well as prolactin (PRL), FSH and estradiol levels were measured by standard RIA kits., Results: Mean IGF-1, LH, FSH, testosterone and estradiol and PRL plasma levels were lower in group A compared to group B. There were no significant differences in mean SHBG, insulin and DHEAS levels. There were also no differences in mean: age, body mass, BMI as well as percentage of each BMI range between groups. Regardless the estradiol level the IGF-I/age link was found in both groups. A IGF-I/IGFBP-3 relation was found in both groups. IGF-I/estradiol link was seen only in group A. In group B hGH/SHBG link was found, in group A this relation was indirect. A link between hGH and testosterone levels was found only in group B. SHBG was related in group B to IGFBP-3, testosterone and to DHEAS. Insulin/IGFBP-3 link was seen in group B. The stepwise multiple regression revealed DHEAS and LH as predictors of IGF-I level in group A, while in group B none of the parameters predicted IGF-I level. The results of the same analysis in case of hGH are as follows: in group A hGH level was predicted by estradiol and SHBG. In group B none of factors predicted hGH levels., Conclusion: Estradiol plasma level is correlated to circulating IGF-I, albeit the relation seems to be biphasic.

Background: Insulin-like growth factor-I (IGF-I) in concert with insulin-like binding protein 3 (IGFBP-3), insulin-like binding protein 2 (IGFBP-2), human growth hormone (GH) and P53 protein is involved in autocrine/paracrine growth signaling pathways as an adaptive response to environmental stimuli., Objective: The study evaluated the local secretion of PRL, hGH, IGF-I, IGFBP-2 and IGFBP-3 by breast cancer tissue explants in relation to the overexpression of P53 protein in breast cancer tissue., Materials and Methods: Breast cancer explants were obtained during radical mastectomies. The overexpression of P53 protein was assessed immunohistochemically using monoclonal antibody (DAKO, Anti-Human P53 protein, clone DO-7); the results of the reaction were stratified into 5 groups. The lack of P53 protein overexpression was defined as 0% of cells that overexpressed P53 protein. IGF-I, IGFBP-3, IGFBP-2, and hGH levels were measured with RIA kits, and prolactin was measured with the MEIA kit., Results: The local secretion of hGH by tumour explants - presenting a positive immunohistochemical reaction (IHCR) to the product of P53 gene - was twice as high as those with no IHCR to product of P53 gene; the opposite was noted in the case of IGF-I, IGFBP-2 and IGFBP-3 secretion. In both cases, the level of hGH, IGF-I and IGFBP-3 secretion did not correlate with the ratio of cells overexpressing P53 protein. There was a significant decrease in local, basic IGFBP-2 secretion along with an increased ratio of cells with positive IHCR to product of P53 gene. Furthermore, local PRL secretion was not correlated with the ratio of cells overexpressing P53 protein in breast cancer tissue. Prolactin also exerts no influence on IGF-I secretion., Conclusion: Our results may suggest the presence of local hGH/IGF-I feedback in breast tissue as well as the possibility of P53/hGH/IGF-I/IGFBP-3 but not P53/PRL/IGF-I axis.

Objective: Ovarian hormonal function may be as important contributing factor to hGH-IGF-I-IGFBP-3 axis as age., Aim: To examine plasma hGH, IGF-1 and IGFBP-3 levels in women with premature ovarian failure compared to healthy normal controls and postmenopausal ones., Patients: Group A-15 women with premature ovarian failure (POF) (mean: age 38.9+/-5.2 years, FSH 101.4+/-29.0 IU/l; 17beta-estradiol 22.5+/-14.6 ng/l). Group B consisted of 15 menopausal women (mean: age 54.7+/-2.7 years; FSH 81.9+/-32.1 IU/l; 17beta-estradiol 17.1+/- 8.0 ng/l). Group C - controls - 15 normally menstruating women (mean: age 37.1+/-9.0 years; FSH 6.2+/-1.0 IU/l; 17beta-estradiol 144.8+/-117.1 ng/l)., Methods: Body mass and BMI were measured. Basic fasting plasma hGH, IGF-I, IGFBP-3, insulin, testosterone and LH as well as prolactin (PRL), FSH and estradiol were assessed by RIA kits. Statistical analysis. Shapiro-Wilk test, Mann-Whitney u-test, Spearman rang correlation coefficient, stepwise multiple regression., Results: Mean serum IGF-I level was the lowest (p<0.005) in group B (172.0+/-54.6 microg/l) and the highest in group C (273.6+/-109.0 microg/l). The mean plasma IGF-I level in group A was similar (NS) (208.3+/-66.5 microg/l) to that found in group B and lower (p<0.02) compared with that in group C. The lowest (p<0.005) serum IGFBP-3 level was found in group B (3.1+/-0.7 microg/l) compared to group C (4.4+/-0.3 microg/l). The mean plasma IGFBP-3 level (3.1+/-1.0 microg/l) in group A was lower than in group C (p<0.005) but identical as in group B. No statistically significant differences between groups were observed in mean hGH levels. Women in group A and C were younger (p<0.001) than those in group B. The lowest mean estradiol level was found in groups A and B. The highest was in group C (p<0.001). Mean plasma LH and FSH levels were higher (p<0.001) in groups A and B vs group C. In group C there were links between IGF-I and age (r=-0.60; p=0.014) The IGF-I/age relation disappeared in the groups A and B (rA=-0.26; rB=0.10; NS). The same regards IGFBP-3/ age link (rA=-0.44, NS; rB=0,31;NS). Estradiol level was related to hGH levels in group C (r=-0.54; p<0.05). In none of groups hGH/IGF-1 as well as IGFBP-3/hGH relations were found. Prolactin accounted for 69% of the variance in IGF-I level in the group B (p=0.003) and for 24% in group A (NS). Testosterone accounted for 88% (p=0.004) of the variance in IGF-I level in group B and IGFBP-3 was responsible for 86% (p=0.038) of the variance in IGF-I level in group C. Again IGFBP-3 was responsible for 47% (p=0.023) in group A and for 49% (p=0.04) in group B of the hGH variance., Conclusions: 17b-estradiol may be as important contributor to insulin-like growth factor-I (IGF-I) plasma level as age in hypoestrogenic, hypogonadotropic women.

The aim of the present study was to investigate direct effects of estrogen (E2) or progesterone (P4) given separately vs. estrogen+progesterone on local IGF-I, IGFBP-3 and IGFBP-2 secretion. Explants obtained from estrogen receptor positive plus progesterone receptor positive (ER+/PR+) and hormone receptors negative (ER-/PR-) tumors were incubated with E2, P4 or both. Tamoxifen was added to E2-exposed cultures; mifepristone (RU 486) was added to P4, and both were given to E2+P4-supplemented cultures. In hormone-dependent and hormone-independent tissues, treatment with estrogen+progesterone increased IGF-I and IGFBP-2 secretion with concomitant decrease in IGFBP-3, in the same manner as E2 or P4 given alone. Tamoxifen decreased the E2- and E2+P4-stimulated IGF-I secretion by hormone-dependent breast cancer explants. RU 486 decreased the P4- and E2+P4-stimulated IGF-I secretion with parallel stimulation of IGFBP-3 secretion by ER+/PR+ explants. Estradiol and progesterone had a synergistic action on IGFBP-2 secretion by hormone-dependent breast cancer explants. In conclusion, the presented data suggest that there is no synergistic action of E2 and P4 in influencing IGF/IGFBPs ratio and, additionally, suggest a protective action of antiestrogen and antiprogestagen against excessive IGF-I secretion.

Objectives: Insulin-like growth factor-I (IGF-I) is regarded as one of mammary tissue proliferative factors. Insulin-like growth factor binding protein-3 (IGFBP-3) limits the IGF-I binding potential to its receptor. That limits the IGF-I bioavailability. Recently experimental studies indicated that insulin-like growth factor binding proteins (IGFBPs) might have their own biological actions beyond their ability to regulate insulin-like growth factors (IGFs). Our earlier results showed the progesterone-induced rise in hGH and IGF secretion by human breast cancer explants., Aim: To determine the ability of progesterone to stimulate simultaneous local IGF-I and IGFBP-3 secretion by non-malignant and malignant mammary tissue collected from different receptor phenotype tumours., Material and Methods: Explants from the tumour and surrounding normal non-malignant tissue were obtained during surging. Breast cancer explants were defined as: ER+ PR+; ER-PR-; ER+ PR-; and ER-PR+. Part of the explants was fixed in 10% buffered formalin for steroid receptor determination by immunohistochemistry. Other parts were cut into small pieces, weight and cultured in Parker medium (M199) supplemented with 5% of calf serum at 37 degrees C in an atmosphere containing 5% CO2 for 48 hours in control medium or with the addition of progesterone (10-7 M). Later media were collected for IGF-I and IGFBP-3 concentration analysis., Results: Progesterone increased (p < 0.01) IGFBP-3/IGF-I index in ER(-)PR(-) non-malignant tissue and decreased the IGFBP-3/IGF-I index in ER(-)PR(+), ER(+)PR(-) non-malignant explants. That increased the IGF-I bioavailability. Breast malignant explants showed the progesterone induced IGFBP-3/IGF-I index decrease. The decrease was most evident (p < 0.01) in malignant explants expressing progesterone receptor., Conclusion: Progesterone increased local IGF-I bioavailability in malignant breast tissue. That phenomenon depended on steroid receptor phenotype of breast tissue and was most evident in tissue expressing progesterone receptor. In non-malignant tissue that phenomenon was also found in estrogen receptor expressing tissue. Lack of steroid receptor expression in breast explants reversed that phenomenon.

The aim of the present study was to compare the ability of natural progesterone and synthetic progestins to stimulate local growth hormone (GH) and insulin-like growth factor I (IGF-I) secretion by breast cancer explants. Explants obtained during surgery were divided according to their estrogen/progesterone receptor phenotype - ER(+)PR(-); ER(+)PR(+); ER(-)PR(+) - as determined by immunocytochemistry. Natural progesterone (10(-5) mol/l) and synthetic progestins (cyproterone acetate (5 x 10(-7) mol/l), norethindrone (10(-5) mol/l), medroxyprogesterone acetate (10(-7) mol/l), and levonorgestrel (10(-7) mol/l) were tested in vitro for their ability to induce secretion of proliferation-promoting agents such as human GH (hGH) and IGF-I. All hormone-dependent breast cancer cell types responded to progesterone stimulation with increased local hGH secretion, while in the non-malignant tissue this effect was observed only in PR(+) cells. Moreover, progesterone in only PR(+) cells in vitro stimulated local IGF-I secretion by both malignant and non-malignant tissue. Medroxyprogesterone and levonorgestrel increased GH secretion by both malignant and non-malignant ER(-)PR(+) breast cancer explants, while cyproterone stimulated it only in non-malignant tissue. None of the synthetic progestins tested in this experiment exerted an effect on GH secretion by both malignant and non-malignant tissue of ER(+) breast cancer explants. The present data additionally showed that, apart from cyproterone, which increased IGF-I secretion in the same manner as progesterone by both malignant and non-malignant ER(-)PR(+) breast explants, other progestins tested had either no effect on IGF-I local secretion or decreased it. Medroxyprogesterone and levonorgestrel induced a decrease in IGF-I secretion noted in ER(+) explants of non-malignant tissue and in malignant ER(-)PR(+) breast tissue. All progestins tested decreased IGF-I secretion by malignant ER(+)PR(+) explants. Taken together, the tested synthetic progestins widely used as oral contraceptives and in hormone replacement therapy were less potent than progesterone in inducing secretion of proliferation-promoting agents such as hGH and IGF-I in ER-containing breast tissue. Despite the lack of confirmation of the link between the use of progestins and breast cancer risk, patients should be informed that the use of certain estrogen/progestin preparations is of no influence on breast cancer risk while others may increase it.

The aim of the study was to evaluate the potential of human breast cancer tissue to secrete growth hormone (GH), insulin-like growth factor I (IGF-I) and prolactin in response to 10(-7) M progesterone stimulation. Explants were divided according to estrogen receptor (ER)/progesterone receptor (PR) phenotype (ER(-)PR(-); ER(+)PR(-); ER(+)PR(+); ER(-)PR(+)). Our results show distinct differences in cultured breast cancer tissue responses to progesterone stimulation with regard to secretion of proliferative agents such as GH, IGF-I and prolactin. All but ER(-)PR(-) breast cancer cell types responded in vitro to progesterone stimulation with an increase in local GH secretion, while in non-malignant tissue progesterone induced local GH secretion only in PR(+) cells. Moreover, only in PR(+) cells did progesterone stimulate local IGF-I and prolactin secretion, in both malignant and non-malignant tissue. This study provides evidence for the first time that in PR(+) breast cancer tissue, progesterone may increase GH, prolactin and IGF-I secretion in both malignant and surrounding non-malignant tissue. These hormones may act as local growth factors that stimulate the proliferation of mammary tumors.

Serum basal fasting IGF-I, hGH, insulin, prolactin and gonadotropins as well as estradiol and SHBG levels were evaluated in: 15 women with the empty sella turcica syndrome [1A], 14 women with the empty sella and pituitary microadenoma[1B], 6 ones with normal CT scan [2A] and 20 subjects with CT signs of pituitary microadenoma [2B]. There were no differences in age of the women. Both mean body mass and body mass index were the highest in group 1A. The lowest mean serum IGF-I, LH, estradiol, SHBG and the highest insulin levels were found in group 1A. Serum IGF-I level correlated negatively with age in all but 1A group. An inverse hGH/age as well as positive hGH/IGF-I correlation found in group 2A was impaired either by presence of the empty sella or microadenoma. IGF-I/insulin correlation did not occur in all but 1A group. Normally existing reverse estradiol/age correlation became positive in group 1A and vanished in patients microadenoma. Serum IGF-I level correlated negatively with gonadotropins in patients with CT signs of microadenoma.