bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transplantable human prostatic carcinoma (PC‐82) in athymic nude mice. II. Tumor growth and androgen receptors
Authors: Van Steenbrugge G. J. , Bolt‐De Vries J. , Blankenstein M. A. , Brinkmann A. O. , Schröder F. H. 
Published: February 2007

AbstractAndrogen receptor (AR) levels were measured in PC‐82 tumor tissue grown in hormonally manipulated nude mice. In the nuclei of tumor tissue from intact male mice a relatively low concentration (mean 25 fmol/mg protein) of androgen receptors (ARn) was found, while no receptors for estrogens or progestins were detected. The total number of androgen receptors in the PC‐82 tumor tissue (measured in the nuclei 1 h after injection of a single high dose of testosterone (T)) was found to be 100 fmol/mg protein. The antiandrogen cyproterone acetate, administered in combination with the high dose of T, significantly lowered the amount of ARn in the tumor tissue. In the nuclei of tumor tissue from intact tumor‐bearing male mice with T‐containing Silastic implants, a 4‐times higher amount of tightly associated AR was found. In addition, an increased growth rate of the tumor was observed following T implantation. This finding suggests that the increased growth rate of the PC‐82 tumor is associated with a continuous occupancy of AR in the nuclei of the tumor tissue. Castration of tumor‐bearing male mice, which arrests the growth of this tumor, did not affect the concentration of ARn in the tissue compared to that of tissue in the intact control situation. In addition, the total amount of AR measured after T injection was not affected by castration. Therefore, the availability of a sufficient and steady level of T in the plasma and consequently the duration of the presence of AR in the nucleus of the PC‐82 tumor tissue, rather than the total concentration of AR, appear to be the limiting factors in the modulation of hormonal responses in this androgen target tissue.
Prolactin effect on the permeability of human benign hyperplastic prostate to testosterone
Authors: Farnsworth Wells E. 
Published: February 2007

AbstractWhile it has been known for over 30 years that prolactin (Prl) synergizes with androgen in the support and stimulation of prostatic growth and metabolism, the evidence that this is accomplished through increasing access of the steroid to the cellular machinery of the gland has arisen only since about 1970. There is widespread uncertainty as to how the Prl effect takes place: by 1) increasing the free steroid concentration in the blood; 2) facilitating the uptake of protein‐bound androgen; 3) increasing, by metabolism or receptor‐binding, the concentration gradient that can support passive diffusion of the steroid across the plasma membrane; or 4) modification of the fluidity of the membrane itself to increase the solubility of the steroid in the lipoprotein and, thus, the ease of penetration of the cell. The present study attempted to learn if Prl is an effective stimulus of androgen uptake when the first three options are not operative. Using an equilibrium exchange procedure to track the uptake of [17α‐3H]‐testosterone ([17α‐3H]‐T) into minced benign hyperplastic human prostate tissue and the irreversible metabolism of the entering steroid to [17α‐3H]‐dihydrotestosterone [17α‐3H]‐DHT, it was found that the rate of production of the 5α‐reduced metabolite, during a 1‐hr incubation in vitro, was directly proportional to the concentration of ovine Prl over the dose range of 0–160 ng/ml. The clinical significance of Prl mediation of steroid uptake is discussed, and suggestions are made as to how the Prl might alter the permeability of the plasma membrane.
Requirements for attachment and subsequent growth of canine prostatic epithelial cells in culture
Authors: Chevalie Simone , Chapdelaine Alcide 
Published: February 2007

AbstractThe attachment and spreading of canine prostatic epithelial cells in primary monolayers and their subsequent proliferation were studied in Primaria and in polystyrene dishes either uncoated or coated with collagen type I, fibronectin, laminin, poly‐D‐lysine, or natural extracellular matrices (nECM) produced by canine prostatic epithelial or fibroblastic cells. Cells were inoculated in serum‐free medium or in medium supplemented with either dialyzed fetal bovine serum (dFBS) or charcoal‐treated dog serum at 10%. Dihydrotestos‐terone (DHT) and 5α‐androstane 3α, 17β‐diol (3α, 17β‐diol) at 10−6 M or a mixture of steroids (androstenedione, testosterone, DHT, 3α, 17β‐diol, 5α‐androstane 3β, 17β‐diol, estrone, and estradiol) were also added. Of all components and dishes tested, only dFBS and the nECM produced by prostatic epithelial cells increased cell attachment (850% and 450%, respectively). When the latter preparations were used in combination, an additive effect (1,500%) was observed, and the subsequent addition of dog serum after the attachment period yielded the highest number of growing prostatic epithelial cells. When prostatic epithelial cells were inoculated either in dishes coated with a nECM derived from prostatic fibroblasts or in presence of dog serum, a 50% inhibition in their plating efficiency was observed. The presence of collagen type I, fibronectin, laminin, or an nECM in the cultures, together with various steroids, had no effect on the cell unresponsiveness to steroids nor did it alter the mitogenic effect of dog serum. Thus, the attachment and spreading of canine prostatic epithelial cells in monolayers are mediated by nonsteroidal factors present in dFBS and in their nECM. Their presence, together with steroids, does not elicit a proliferative response to steroids nor did it increase the effect of growth‐promoting factors in dog serum.
5α‐reductase activity in epithelium and stroma of prostates from intact and castrated dogs treated with androstenedione, the aromatase inhibitor 1‐methyl‐1,4‐androstadiene‐3, 17‐dione, and cyproterone acetate
Authors: Tunn Sabine , Hochstrate Holger , Habenicht Ursula‐F. , Krieg Michael 
Published: February 2007

AbstractIn addition to the histology of epithelial and stromal elements of prostates from intact dogs (group 0) and castrated dogs (group I), the latter of which were treated with androstenedione (group II), androstenedione plus the aromatase inhibitor 1‐methyl‐1,4‐androstadiene‐3,17‐dione (group III), or androstenedione plus aromatase inhibitor and cyproterone acetate (group IV) (Habenicht and El Etreby: The Prostate 11:133–143, 1987) it was of interest to study the influence of such in vivo treatment on the prostatic 5α‐reductase, which is responsible for the cellular conversion of testosterone to 5α‐dihydrotestosterone. Michaelis constants (KM) and maximal activities (Vmax) of 5α‐reductase were determined under optimized incubation conditions in mechanically separated epithelium and stroma. The metabolites were separated by high‐performance liquid chromatography and determined radiometrically. The main results were: 1) The mean KM (nM ± SEM) was significantly (P < .001) higher in epithelium (892 ± 132) than stroma (70 ± 11). The same was true concerning the Vmax (pmol · mg protein−1 · h−1 · SEM) in epithelium (54.6 ± 5.8) as compared to stroma (13.0 ± 2.0). 2) No specific in vivo or in vitro effect of the aromatase inhibitor on the KM and Vmax data was found. 3) In prostates of intact dogs and dogs of group II the proportion of epithelial 5α‐reductase exceeded distinctly that of stromal 5α‐reductase. 4) In groups I, III, and IV the proportion of epithelial 5α‐reductase was rather low. These data were discussed in the light of the histological findings.
Sex‐hormone‐induced inflammation and fibromuscular proliferation in the rat lateral prostate
Authors: Lee Robinette C. 
Published: February 2007

AbstractThe subacute administration of estradiol‐17β was shown to be a potent inducer of an inflammatory response specific to the lateral prostate of the castrated Wistar rat. The subsequent administration of dihydrotestosterone restored the wet weight of the gland while maintaining the inflammation established with estrogen treatment. These changes are histologically similar to a spontaneously arising nonbacterial prostatitis previously reported by others in the aging rat lateral prostate.When the same hormones were administered on a chronic basis, the intensity of the inflammation increased with time and was accompanied by a fibromuscular proliferation that consisted of fibroblasts, smooth muscle cells, and collagen. These chronic changes correlated well with studies by other investigators on human benign prostatic hyperplasia (BPH) where certain forms of BPH were associated with a significant degree of inflammation and fibromuscular growth.The present studies therefore establish a model system for the hormonal induction of an inflammatory reaction in the rat lateral prostate that precedes and could be causally related to proliferative responses in the fibromuscular stroma. The potentially important similarities that exist between these experimental findings and the human problems of nonbacterial prostatitis and benign prostatic hyperplasia warrant additional study.
Prolactin and luteinizing hormone‐releasing hormone receptors in human benign prostatic hyperplasia and prostate cancer
Authors: Kadar Tibor , Ben‐David Menashe , Edson Pontes J. , Fekete Matyas , Schally Andrew V. 
Published: February 2007

AbstractUsing a sensitive micromethod for the determination of prolactin (PRL) binding sites based on 125I‐human PRL ligand, PRL receptor levels in specimens of benign prostatic hyperplasia (BPH) and human prostate cancer were estimated by the one‐point assay system. Ten of 19 BPH specimens (53%), showed significant PRL binding, four being in the 9–12 fmol/mg range. All ten of these cases had an histological diagnosis of nodular glandular hyperplasia. Of ten adenocarcinomas examined, four samples (40%) exhibited positive PRL binding, the highest receptor levels being 10.2 fmol/mg protein. To characterize the receptors from BPH membranes, samples were then separately pooled according to the results obtained in one‐point assays. In the PRL‐negative pool no displacement could be detected. In the PRL‐positive pool, the Scatchard analysis revealed one class of receptors with an average affinity Kd = 1.1 × 10−9 M and capacity Bmax = 287 fmol/mg protein. In the prostate cancer specimens, luteinizing hormone‐releasing hormone receptors with a high affinity and a low capacity were also found. The results indicate the presence of prolactin receptors in prostate cancer and in BPH. The clinical implications of such findings are not clear, but it is possible that a certain proportion of BPH and prostate cancers might be in part PRL dependent. Further studies are necessary to ascertain this hypothesis in an attempt to improve the treatment of BPH and prostate cancer.
Ornithine decarboxylase and S‐adenosylmethionine decarboxylase activity in the accessory sex organs of intact, castrated, and androgen‐stimulated castrated rats
Authors: Fjösne Hans E. , Strand Harald , Östensen Mari‐Ann , Sunde Arne 
Published: February 2007

AbstractWe have studied the activities of ornithine decarboxylase and adenosylmethionine decar‐boxylase in the 106‐m/s2 supernatants of the different lobes of the prostate and the seminal vesicles of castrates, androgen‐stimulated castrates, and intact controls.After castration L‐ornithine decarboxylase (ODC) and S‐adenosyl‐L‐methionine decarboxylase (AMDC) activities fell in all tissues examined. The induction of kinetics was followed for 72 h after administration of testosterone propionate to castrated rats. AMDC activities increased more rapidly than ODC activities in every tissue studied. Peak activities were reached more rapidly in the dorsal lobe than in the other tissues. ODC activity of the ventral lobe increased linearly for 48 h after stimulation. In the other tissues studied, ODC activity reached a maximum after 24 h and thereafter leveled off or decreased.In conclusion we have found distinct differences in ODC and AMDC activity in various tissues and major differences between treatment groups, with near extinction of activity at castration. In castrates stimulated with testosterone, the between‐group differences prevailed but with different patterns of ODC versus AMDC activity. AMDC is seemingly rate‐limiting in polyamine synthesis in stimulated tissues, while ODC controls synthesis in tissues from castrated rats.
Visualization and quantification of transplanted dunning prostate tumors in rats using magnetic resonance imaging
Authors: Rudin M. , Qureshi S. , Tolcsvai L. , Siegel R. A. 
Published: February 2007

AbstractQuantitative magnetic resonance imaging (MRI) has been used for the in vivo size determination of subcutaneously implanted Dunning R3327–H tumors in male Copenhagen‐Fisher rats (N = 18). Images have been recorded using a multislice spin‐echo sequence SE(1000/36) with a resolution of 0.2 times; 0.2 mm2 in the imaging plane and a slice thickness of 2 mm. The reliability in the MRI size determination was of the order of 10%. The MRI results were compared with caliper measurements. Five months after tumor implantation nine rats were castrated. Orchiectomy led to a marked and statistically significant reduction in tumor growth rate as determined by both methods of quantification. Qualitative MRI information regarding the tumor morphology was compared with that for histological specimens.
Predictive sites of inflammatory manifestation in the prostatic gland: An experimental study on nonbacterial prostatitis in the rat
Authors: Aronsson Anita , Dahlgren Sven , Gatenbeck Lars , Strömberg Lennart 
Published: February 2007

AbstractIn rats that had been subjected to standardized experimental stress stimuli for 3 and 10 days, respectively, prostatic inflammatory changes of type nonbacterial prostatitis were found in a lobe‐differentiated histological examination. The inflammatory manifestations were marked in the ventral lobes, whereas they were sparse in the dorsolateral lobes. The lobe difference in this respect corresponds to a concomitant difference in morphology and tissue chemical content.
Comparative analysis of growth factors in normal and pathologic human prostates
Authors: Nishi Nozomu , Matuo Yuhsi , Kunitomi Kimito , Takenaka Ikumasa , Usami Michiyuki , Kotake Toshihiko , Wada Fumio 
Published: February 2007

AbstractGrowth factors, as detected by DNA synthesis stimulating activity for BALB/c 3T3 cells, in normal, benign hypertrophic and cancerous human prostates were analyzed. The total content (units per gram of tissue) in benign hypertrophic prostate was two to four times higher than those in normal and cancerous prostates. In all the three groups, heparin‐binding growth factor, growth factor adsorbed to heparin‐Sepharose in the presence of 0.5 M NaCI, accounted for about 80‐95% of the total growth factor content. Qualitative analysis using a heparin‐Sepharose column revealed two types of heparin‐binding growth factor in the prostates, one eluted from the column at 1.2‐1.3 M NaCl and the other at 1.5‐1.8 M NaCI. The latter was the predominant type in all groups. In addition to the growth factors detected with BALB/c 3T3, a growth factor with specific action upon MC3T3‐E1 mouse osteoblasts was found in prostatic cancer, but not in normal and benign hypertrophic prostates.
Estramustine inhibits monocyte phagocytosis
Authors: Bjermer Leif , Schoultz Eva Von , Norberg Bo , Henriksson Roger 
Published: February 2007

AbstractEstramustine‐phosphate (EMP) influence on human monocyte phagocytosis of fluorescein isothiocyanate (FITC)‐labeled yeast cells was measured in vitro. The method used, a modification of Hed's technique (FEMS Microbiol Lett 1:357, 1977), can differentiate between yeast cell engulfment and adherence to the phagocytotic cell surface. EMP is now accepted in the treatment of advanced prostatic carcinoma. In concentrations corresponding to the clinical situation (20‐40 μg/ml), it dramatically inhibited the process of phagocytosis. The engulfment phase was inhibited, whereas cell adherence was less affected. This might be due to direct interaction with the microtubulus system. The effects were totally reversible. In contrast, the metabolites estradiol and normustine did not affect engulfment of yeast cells, either as single agents or combined. The results demonstrate that the EMP complex caused an impaired phagocytosis, which could be of pathophysiological significance in the compromised cancer patients.
Efficacy and advantages in the use of low doses of anandron and estrogen combination in the treatment of prostate cancer
Authors: Rao B. Ramanath , Geldof A. A. , van Der Wilt C. L. , de Voogt H. J. 
Published: February 2007

AbstractTreatment effects of RU 23908 antiandrogen (Anandron®) and estrogen in low doses on hormone‐dependent rat prostatic adenocarcinoma (R3327‐H) were investigated. Tumorbearing Copenhagen rats were treated for 6 weeks with 8 μg Anandron and 1 μg estradiol‐17β every two days. Reduction and counteraction of androgen synthesis and action was established by an observed decline in serum testosterone level and by changes in both histology and weight of androgen target organs. Prostate tumor growth rate was significantly retarded in rats treated with Anandron/Estradiol combination compared to untreated intact control and was equal to the slow growth rate in castrate tumor‐bearing animals. Tumor histology changes during treatment correlated with the observed growth rate retardation. Areas of necrosis, metaplasia. and acellularity were more frequently observed in tumors of Anandron/Estradiol‐treated compared to castrated rats. These results suggest that low doses of Anandron and estrogen can effectively be combined as a complete androgen counteracting therapy for hormone‐dependent prostatic carcinoma with minimal undesired side effects.
Significance of duct‐acinar dysplasia in prostatic carcinogenesis
Authors: McNeal John E. 
Published: February 2007

AbstractDuct‐acinar dysplasia of the prostate is defined as a premalignant lesion characterized by cytologic, and especially nuclear, abnormalities that resemble those of carcinoma and affect the lining epithelial cells of preexisting ducts and acini. A progressive continuum of cytologic abnormality is divided into three grades, with grade III identified by the presence of numerous large nucleoli. Foci of carcinoma have been identified at their point of origin from dysplastic ducts, which confirms the malignant potential of this lesion. Foci of dysplasia are found in roughly 80% of prostates with invasive carcinoma and 40% of glands without cancer. It is concluded that the majority of prostate cancers probably arise within dysplasia foci. Foci of grade III dysplasia occasionally evolve by proliferation of cells to fill duct lumens. The intraluminal cell masses display a cribriform pattern, which has previously been interpreted as a variant of invasive Gleason grade 3 carcinoma. Dysplasia is further linked biologically to malignant transformation by the immunohistochemical demonstration of progressive loss of cytoplasmic differentiation markers and inappropriate overexpression of some markers during the evolution of dysplasia.
Application of octadecylsilyl‐silica in purification studies related to the nontransformed rat ventral prostate androgen receptor
Authors: Koutsilieris Michael , Bouthillier François , Grondin Francine , Radwan Farouk , Carmel Michel , Elhilali Mostafa , Lehoux Jean‐Guy 
Published: February 2007

AbstractWe investigated the application of octadecylsilyl (ODs)‐silica in studies related to characterization and purification of the nontransformed rat ventral prostate androgen receptor. The results indicated that ODS‐silica successfully separates the free [3H]R1881 from the labeled [3H]R1881 transformed (4‐5s) and nontransformed (8‐9s) rat ventral prostate androgen receptors. Partial purification of the 8‐9s receptor form was performed by the fractionation of rat cytosol using cartridges of the ODS‐silica and fast‐flow‐rate phosphocellulose chromatography. Further purification was accomplished by differential chromatography (DEAE‐ cellulose and slow‐flow‐rate phosphocellulose chromatography). This partially purified 8‐9s receptor, when analyzed on a gel permeation high‐performance liquid chromatography column, resulted in a three‐peak pattern of UV absorbance. One of these peaks corresponded to a 59‐kD non[3H]R1881‐binding protein and the remaining two corresponded to 270‐kD and 190‐kD[3H]R1881‐binding proteins. These results demonstrate the usefulness of ODS‐silica in androgen receptor studies. The association of a 59‐kD nonsteroid binding protein with the nontransformed rat ventral prostate androgen receptor is discussed.
Partial purification of a major type of rat prostatic growth factor: Characterization as an epidermal growth factor‐related mitogen
Authors: Nishi Nozomu , Matuo Yuhsi , Wada Fumio 
Published: February 2007

AbstractThe dorsolateral prostate of rats contains a mitogen that shares several properties with epidermal growth factor (EGF), which was designated as prostatic EGF‐related mitogen (PEM). PEM was purified about 2,100‐fold using molecular‐sieve and ion‐exchange chromatography. Final preparation stimulated DNA synthesis in BALB/c 3T3 cells at a concentration as low as 1.5 ng/ml and competed with 125I‐EGF for binding to cell surface receptors. PEM had a molecular weight of about 14,000 and an isoelectric point of about 4.5, being heat‐and acid‐stable but inactivated by dithiothreitol. The primary cultured rat dorsolateral prostate epithelial cells required EGF for maximum growth. Partially purified PEM fully substituted for EGF in the primary culture system at a concentration as low as 90 ng/ml. However, the activity of PEM was hardly suppressed by antimouse EGF antiserum. These findings suggest that PEM is a member of the EGF family but has a higher molecular weight (high molecular weight EGF).
Expression of basic fibroblast growth factor mRNA in benign prostatic hyperplasia and prostatic carcinoma
Authors: Mydlo Jack H. , Michaeli Joseph , Heston W. D. W. , Fair W. R. 
Published: February 2007

AbstractIn our previous work we demonstrated that prostate‐derived growth factor (PrGF) is homologous to basic fibroblast growth factor (bFGF), not acidic fibroblast growth factor (aFGF). Using Northern blot analysis we now show that the messenger RNA for bFGF but not aFGF is expressed in benign prostatic hyperplastic (BPH) tissue as well as in carcinoma of the prostate (CAP). This not only corroborates our previous results, but suggests that prGF is produced locally and not merely stored in the prostate. The demonstration of local production of bFGF by prostate tissue may indicate that this growth factor plays a role, either alone or in conjunction with other factors, in the etiology of benign hyperplasia or prostatic cancer.
Cardiovascular follow‐up of patients with prostatic cancer treated with single‐drug polyestradiol phosphate
Authors: Henriksson Peter , Eriksson Ambjörn , Stege Reinhard , Collste Lars , Pousette Åke , Von Schoultz Bo , Carlström Kjell 
Published: February 2007

AbstractThirty‐eight patients with cancer of the prostate were treated with strict parenteral estrogen in the form of monthly polyestradiol phosphate injections–160 mg, 240 mg, and 320 mg—in this nonrandomized study. In contrast to studies with oral estrogens, there have been no cardiovascular complications at a mean follow‐up of 12.9 ± 0.7 months (SEM). Twenty‐nine of the 38 patients (76%) have responded to therapy.