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Dive into the research topics where Jacek Daroszewski is active.

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Featured researches published by Jacek Daroszewski.


Steroids | 1998

Concentration of sex steroids in adipose tissue after menopause.

Jadwiga Szymczak; Andrzej Milewicz; Jos H.H. Thijssen; Marinus A. Blankenstein; Jacek Daroszewski

Adipose tissue is a site of uptake, storage, action, and metabolism of sex steroids. After menopause aromatization of androgens to estrogens in adipose tissue is one of the most important sources of estrogen in the circulation and for peripheral tissues. The aim of this study was to estimate local sex steroid concentrations in breast and abdominal subcutaneous (s.c.) adipose tissue, to compare them with plasma concentrations and to investigate possible correlations with body mass index (BMI). The patients were postmenopausal women undergoing surgery for non-oncological reasons (Group A; n = 35) and breast cancer patients (group B; n = 19). The concentrations of estrone, 17 beta-estradiol, estrone sulfate, 17 beta-estradiol sulfate, androstenedione, androstenediol (androst-5-ene-3 beta, 17 beta-diol), testosterone and dehydroepiandrosterone were measured. The method was based on frozen tissue homogenization, extraction with ethanol: acetone, delipidation, extraction of estrogens with ether, and of androgens with iso-octane in toluene, followed by RIA. The mean levels of steroids were higher in fat than in plasma, apart from testosterone. Levels of sulfates of estrogens and androstenediol were higher in breast than abdominal adipose tissue, and levels of estradiol lower. Positive correlations were found between BMI and tissue and plasma concentration of both estrone and androstenedione.


The Journal of Steroid Biochemistry and Molecular Biology | 1999

Intratumoral levels of estrogens in breast cancer

Marinus A. Blankenstein; J van de Ven; I. Maitimu-Smeele; G.H. Donker; P.Chr. de Jong; Jacek Daroszewski; Jadwiga Szymczak; Andrzej Milewicz; J.H.H. Thijssen

Breast cancer tissue is an endocrine organ and particularly the estrogen biosynthetic properties of this tissue have been well studied. The concentration of estradiol in breast cancer tissue from postmenopausal patients is considerably higher than that in the circulation and appears to depend largely on local production. Androgenic precursor steroids are abundantly present, but estrogen storage pools like fatty acid derivatives appear to be less important than initially thought. New, potent and highly specific aromatase inhibitors effectively inhibit peripheral conversion of androgens to estrogens (Cancer Res. 53: 4563, 1993) as well as intratumour aromatase, median aromatase activity being 89% lower in the tissue from patients pretreated with aromatase inhibitor 7 days prior to surgery (P < 0.001). Also the intratissue concentrations of estrogens were decreased (64% and 80% reduction, respectively for estrone and estradiol; P = 0.001 and <0.05; Cancer Res. 57: 2109, 1997). These results illustrate that intratissue estrogen biosynthesis is effectively inhibited by the new generation of aromatase inhibitors. The pathophysiological consequences of this finding are currently under study.


The Journal of Steroid Biochemistry and Molecular Biology | 1992

On the significance of in situ production of oestrogens in human breast cancer tissue.

Marinus A. Blankenstein; I. Maitimu-Smeele; G.H. Donker; Jacek Daroszewski; Andrzej Milewicz; J.H.H. Thijssen

We have previously shown that human breast cancer is autonomous in the regulation of its intra-tissue oestradiol concentration. Breast fatty tissue does not have this capacity, but rather reflects changes in the peripheral oestradiol concentration. To further evaluate the relative contribution of breast cancer and fatty tissue to the maintenance of tumour oestradiol we investigated whether a tumour-directed gradient in aromatase activity and oestrogen levels existed in mastectomy specimens. No such gradient was found, however, for aromatase, oestrone, oestradiol and their sulphates. Aromatase activity (expressed per gram of tissue) and the concentrations of oestradiol, oestradiol sulphate and oestrone sulphate were higher in tumour than in breast fatty tissue. Fatty tissue had a higher oestrone concentration. It is tentatively concluded that breast tumour aromatase activity is more important for the maintenance of tumour oestradiol levels than aromatase in breast fatty tissue.


The Journal of Steroid Biochemistry and Molecular Biology | 1991

Endogenous steroid hormones and local aromatase activity in the breast

J.H.H. Thijssen; Marinus A. Blankenstein; G.H. Donker; Jacek Daroszewski

To test the hypothesis of an increased activity of the enzyme aromatase in adipose tissue from affected when compared with non-affected quadrants of patients with breast cancer, the aromatase activity has been measured in tumour and fatty tissues dissected at specific sites from the breasts of 16 patients. Activity was measured after extensive purification of the product formed. Results, expressed in fmol/g of tissue, did not show a higher activity in the affected vs the non-affected quadrants. In the tumours, higher activities were found when expressed per g of tissue. Per mg of DNA, an indicator of the number of cells, tumour enzymatic activity was lower than in fatty tissues. The relations between the products of aromatase, oestrone and oestradiol in the various tissues point to the importance of additional enzymatic processes, especially of the reductive 17 beta-oestradiol dehydrogenase, in the accumulation of high quantities of oestradiol in the malignant tissue.


Journal of Bone and Mineral Metabolism | 2005

Bone mineral density and turnover in patients with acromegaly in relation to sex, disease activity, and gonadal function

Marek Bolanowski; Jacek Daroszewski; Marek Mędraś; Beata Zadrożna-Śliwka

Acromegaly is a rare disease caused by growth hormone (GH) hypersecretion. GH and insulin-like growth factor-I (IGF-I) exert anabolic activity in bones. Nevertheless, bone mineral density (BMD) loss is not uncommon in patients with acromegaly. It is assumed to be due to hypogonadism associated with the acromegaly. The aim of the study was to examine BMD at various skeletal sites and bone turnover and to assess the influence of impaired gonadal function and disease activity on BMD and turnover changes in acromegaly. A total of 62 patients were studied (40 women, 22 men). Among the women, 22 had active disease and 18 were cured; 16 women had normal gonadal function, and 24 were hypogonadal. Altogether, 12 men presented with active acromegaly, and 10 were cured; normal gonadal function was found in 10 men, and hypogonadism was diagnosed in 12 men. Controls were 30 healthy subjects. Densitometry using dual-energy X-ray absorptiometry of the lumbar spine, proximal femur, forearm, and total body was carried out. Bone turnover was studied based on serum osteocalcin, C-terminal collagen type 1 crosslinks, and bone alkaline phosphatase concentration. A disadvantageous effect of acromegaly on bone density was associated with hypogonadism in the distal radius (in women), the proximal femur (in men), and the total body (both sexes). An anabolic effect of GH during active acromegaly was present in the proximal femur only in men. We confirmed increased bone turnover in the presence of acromegaly, and these changes were similar regarding the activity of the disease and the gonadal status.


Gynecological Endocrinology | 1992

Estrogens in plasma and fatty tissue from breast cancer patients and women undergoing surgery for non-oncological reasons

Marinus A. Blankenstein; Jadwiga Szymczak; Jacek Daroszewski; A. Milenncz; J.H.H. Thijssen

Breast cancer tissue is able to maintain the tissue estradiol level in spite of the massive decrease in plasma estradiol associated with menopause, whereas fatty tissue from breasts with malignancies more closely reflects the changes in plasma. In the present study estrone and estradiol levels in fatty tissues from different origins were compared to evaluate the capacity of distant fatty tissues to act as estrogen reservoirs. Abdominal fat was obtained from 25 premenopausal and 20 postmenopausal women who underwent surgery for non-oncological reasons. Estrone and estradiol levels in these tissues were compared to those in breast fatty tissue from breast cancer patients. Plasma estrogen levels were not different in the two groups. In both groups, median plasma estradiol levels dropped sharply with menopause (from 363 to 40 pmol/l in breast cancer patients; from 280 to 45 pmol/l in the non-oncological patients; p less than 0.002), whereas a significant decrease in plasma estrone was observed only in the breast cancer patients (from 238 to 140 pmol/l; p less than 0.02). In premenopausal women, median estrone and estradiol levels in breast fatty tissue (1135 and 375 fmol/g, respectively) and abdominal tissue (1390 and 470 fmol/g, respectively) were not different. In postmenopausal women, however, significantly higher estrone levels (663 vs. 508 fmol/g; p less than 0.01) and estradiol levels (245 vs. 187 fmol/g; p less than 0.02) were found in abdominal fatty tissue. In view of the absolute estrogen levels in breast and abdominal fatty tissue and in plasma, we conclude, however, that it is unlikely that remote fat contributes substantially to the maintenance of estrogen levels in breast cancer tissue.


The Journal of Steroid Biochemistry and Molecular Biology | 1992

Tissue androgens and the endocrine autonomy of breast cancer

Marinus A. Blankenstein; I. Maitimu-Smeele; G.H. Donker; Jacek Daroszewski; Andrzej Milewicz; J.H.H. Thijssen

To evaluate whether a tumour-directed gradient in androgen levels in fatty tissue can account for the maintenance of intra-tissue oestradiol levels, androstenedione (Adione), dehydroepiandrosterone (DHEA), testosterone (Testo) and androstenediol (Adiol) were assayed in breast tumour tissues and in fatty tissue taken at different distances from the tumour. The concentration of Adione was significantly lower in tumour tissue (5.6 +/- 1.5 pmol/g tissue; mean +/- SEM; n = 14) than in the adjacent fatty tissue (20.4 +/- 2.2; P less than 0.005). Testo, by contrast, occurred in equal concentrations in tumour (0.80 +/- 0.11) and in adjacent fatty tissue (0.70 +/- 0.07). Adione levels tended to be lower after the menopause only in fatty tissue, not in the tumour tissue; for Testo no differences were observed between samples from pre- and postmenopausal patients. Tumour DHEA levels (57 +/- 12 pmol/g tissue) were lower than those in fatty tissue (117 +/- 17; P less than 0.02). As with Adione, fatty tissue DHEA concentrations tended to be higher in pre- than in postmenopausal patients. Adiol showed a similar pattern as Testo. For none of the aromatase substrates nor their precursors a tumour-directed gradient was observed. The concentration of Adione in breast cancer tissue is much lower than the reported Km of the aromatase system for Adione. We have concluded, therefore, that the maintenance of oestradiol concentrations in tumour tissues is not substrate-driven.


The Journal of Steroid Biochemistry and Molecular Biology | 1993

Local aromatase activity in human breast tissues

J.H.H. Thijssen; Jacek Daroszewski; Andrzej Milewicz; Marinus A. Blankenstein

The presence of oestradiol in malignant breast cells is considered to be an important factor in the promotion of growth of the tumor. Therefore the regulation of the local high intra-tissue oestradiol concentrations, regardless of plasma concentrations, has been investigated. Experimental evidence suggests that in situ biosynthesis of oestrogens is at least partly responsible for the local accumulation of these steroids. In this paper we report further data on measurements in fatty and tumor tissues of local aromatase activities and of concentrations of substrates and products of this enzyme. Data are given on localization of aromatase and on steroid concentrations in tumors and in adipose tissues dissected from different quadrants of breasts with malignant tumors. In adipose tissues small variations in steroid concentrations in fatty tissues were found. No tumor-directed gradients in the adipose tissue-concentrations of the androgens dehydro-epiandrosterone, 5-androstene-3 beta, 17 beta-diol, 4-androstene-3,17-dione and testosterone and of the oestrogens oestradiol, oestrone and their sulfates could be detected. Furthermore no consistent pattern could be recognized in the aromatase activities in the fatty tissues dissected from tumor-bearing and non-affected quadrants of the same breast. No correlations between aromatase activity measured in vitro and product concentrations in vivo were found. Therefore the mechanisms for regulation of the local oestradiol levels in breast tissues remain unknown.


Endocrine Research | 2012

CD8+CD28− Lymphocytes in Peripheral Blood and Serum Concentrations of Soluble Interleukin 6 Receptor are Increased in Patients with Graves’ Orbitopathy and Correlate with Disease Activity

Miroslaw Slowik; Donata Urbaniak-Kujda; Anna Bohdanowicz-Pawlak; Katarzyna Kapelko-Słowik; Jaroslaw Dybko; Dariusz Wolowiec; Bozena Jazwiec; Jacek Daroszewski

Background. The extrathyroid, orbital manifestation of Graves’ disease (GD)—Graves’ orbitopathy (GO)—presents a difficult clinical problem. The immunological status of GO patients is still under investigation. The aim of this study was to assess the serum concentration of interleukin 6 (IL-6), soluble interleukin 6 receptor (sIL-6R), and CD8+CD28− lymphocytes in GO patients and to evaluate if these parameters were associated with disease activity. Patients. Thirty-nine patients (29 women and 10 men, aged 24–71, mean 50.18) with newly diagnosed GD were enrolled in the study. Active GO was diagnosed in 20 patients. The control group included 12 healthy individuals. Methods. Serum concentrations of IL-6 and sIL-6R were estimated by ELISA. Percentages of CD8+CD28− lymphocytes in peripheral blood were assessed by flow cytometry. Results. Mean serum IL-6 and sIL-6R concentrations were significantly higher in all GD patients and in GO and non-GO patients than in normal controls. In all GD patients and the non-GO group, serum IL-6 and sIL-6R concentrations were significantly reduced after efficient treatment. In GO patients, only serum sIL-6R concentration was significantly lower after efficient treatment. In all GD patients, the mean percentage of CD8+CD28− lymphocytes was significantly lower after efficient treatment. In GO patients, the mean percentage of CD8+CD28− lymphocytes was significantly higher than in the non-GO group or in normals. Moreover, in the GO group, the mean percentage of CD8+CD28− lymphocytes was significantly lower after treatment. Conclusion. Our results have shown that CD8+CD28− lymphocyte percentage in peripheral blood and serum concentration of sIL-6R are increased in GO patients and correlate with disease activity.


Endokrynologia Polska | 2014

Acromegaly--a novel view of the patient. Polish proposals for diagnostic and therapeutic procedures in the light of recent reports.

Marek Bolanowski; Marek Ruchała; Wojciech Zgliczyński; Beata Kos-Kudła; Agata Bałdys-Waligórska; Grzegorz Zieliński; Tomasz Bednarczuk; Alicja Hubalewska-Dydejczyk; Grzegorz Kamiński; Bogdan Marek; Jacek Daroszewski; Ryszard Waśko; Andrzej Lewiński

is usually delayed and is often associated with the development of various complications causing premature mortality. In patients with hypertension, heart failure, diabetes, and arthropathy that is non-specific for age, attention should be paid to the occurrence of somatic signs of acromegaly. As a screening test, insulin-like growth factor-1 (IGF-1) concentration should be assessed. Further diagnostic and treatment procedures are possible in specialised centres. The first-line therapy is selective transsphenoidal adenomectomy. Patients with a good prognosis related to a surgical removal of the pituitary tumour should be referred only to centres experienced in performing this type of procedure, after pharmacological preparation. Other patients, and those who have not recovered after surgical treatment, should be subjected to long-term pharmacotherapy with long-acting somatostatin analogues. In each case, the complications of acromegaly should be followed-up long-term and actively treated. This proposed new recommendation should be helpful for the management of patients with acromegaly.

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Marek Bolanowski

Wrocław Medical University

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Katarzyna Pukajlo

Wrocław Medical University

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Irena Frydecka

Polish Academy of Sciences

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Tomasz Bednarczuk

Medical University of Warsaw

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Anna Noczyńska

Wrocław Medical University

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Andrzej Gamian

Polish Academy of Sciences

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