Heparin-binding growth factor isolated from human prostatic extracts

Prostatic tissue extracts from patients with benign prostatic hyperplasia (BPH) and prostatic carcinoma were fractionated using heparin-Sepharose chromatography. The mitogenic activity of eluted fractions on quiescent subconfluent Swiss Albino 3T3 fibroblasts was tested employing a tritiated-thymidine-incorporation assay. Two peaks of activity were consistently noted--one in the void volume and a second fraction which eluted with 1.3-1.6 M NaCl and contained the majority of the mitogenic activity. Both non-heparin- and heparin-binding fractions increased tritiated incorporation into a mouse osteoblast cell line (MC3T3), while only the heparin-binding fractions stimulated a human umbilical vein endothelial cell line (HUV). No increased uptake of thymidine was seen using a human prostatic carcinoma cell line (PC-3). Sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS/PAGE) of lyophilized active fractions showed a persistent band at 17,500 daltons. The purified protein demonstrated angiogenic properties using the chick embryo chorioallantoic membrane (CAM) assay. Western blot analysis using antibodies specific to basic fibroblast growth factor (bFGF) or acidic FGF (aFGF) demonstrated that the former, but not the latter, bound to prostatic growth factor (PrGF), and inhibited its mitogenic activity as well. It appears that PrGF shares homology with basic fibroblast growth factors.

Dihydrotestosterone measured in core biopsies from prostatic tissues

Dihydrotestosterone (DHT) levels were measured and related to the content of DNA in 10- to 15-mg tissue samples obtained by punch biopsies from the prostatic gland. The aim of the study was to provide an opportunity to detect the variation of dihydrotestosterone (DHT) in prostatic tissue on endocrine manipulations in phase III studies of metastatic prostatic cancer. DHT was assayed in ranges of 27.9 to 102.9 pg/ml or when related to DNA from 0.57 to 4.00 pg/micrograms DNA by modifying a commercial testosterone/dihydrotestosterone kit. Preliminary clinical results from nine patients with prostatic cancer and eight with benign hyperplasia showed a significantly lower DHT/DNA ratio in prostatic cancer. The predictive value of the histological grading was improved by estimates of the weighted mean nuclear volume. The trend that mean nuclear volume of prostatic cancer exceeded the mean nuclear volume of hyperplasia was clear, and a significantly larger nuclear variation was demonstrated in the malignant specimens. Neither the DHT/DNA ratio nor the mean nuclear volume appears to be sufficient to guide the handling of individual patients, but the described methods enable us by repeated measurements to follow the course of disease and response to treatment.

Partial purification of a major type of rat prostatic growth factor: characterization as an epidermal growth factor-related mitogen

The 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).

Tissue type plasminogen activator as a marker for functional zones, within the human prostate gland

The cellular distribution of tissue plasminogen activator in the prostate central zone, prostate peripheral zone, and seminal vesicle was studied by using immunohistochemistry. Samples of these three regions were taken from 20 radical prostatectomy specimens. Sixteen of 18 central zone samples showed positive staining of 20-90% of the epithelial cells. All 15 peripheral zone samples were negative, and only three of 14 seminal vesicles showed positive staining, which was present in less than 5% of cells. The distribution of tissue plasminogen activator within the prostate was the same as that previously reported for pepsinogen II. This suggests that the central zone of the prostate may be the selective site of origin for proteolytic enzymes in seminal fluid.

Intraluminal crystalloids in whole-organ sections of prostate

Demonstration of intraluminal crystalloids and mucin can aid in the diagnosis of prostatic adenocarcinoma. Crystalloids have been reported in 10% to 23% of prostatic adenocarcinomas. This incidence may not be accurate, however, because previous studies were based on specimens obtained by transurethral resection or transrectal biopsy. This study was based on the examination of 54 prostates (9 obtained from radical prostatectomies for prostate cancer and 45 from cystoprostatectomies for bladder carcinoma) processed by a whole-organ section method. Crystalloids were found in all nine prostatic carcinomas from radical prostatectomy specimens. Thirty-one of 45 specimens from cystoprostatectomies had single or multiple foci of adenocarcinoma; of these, 20 cases (64.5%) had crystalloids. Numbers of crystalloids varied not only from case to case but also from area to area within the same case. Crystalloids were occasionally identified in benign and dysplastic glands that were adjacent to areas of carcinoma. Cases without prostatic carcinoma and benign or dysplastic glands distant from areas of carcinoma did not contain crystalloids. Twenty-four prostatic adenocarcinomas had intraluminal mucin; mucin was not found in benign glands. In conclusion we found the incidence of crystalloids to be higher than that reported in previous studies, a difference we believe is because of sampling. We confirm previous observations that intraluminal crystalloids and mucin are helpful in diagnosing prostate adenocarcinoma.

Prostate-specific antigen in prostatic cancer

In an attempt to establish the value of prostate-specific antigen (PSA) in prostatic cancer, serum PSA measurements were performed in 600 patients, including 75 previously untreated prostatic cancer patients. The mean PSA levels in the benign prostatic hypertrophy (BPH) and cancer groups were highly significantly different, but less difference was found between BPH and localized prostatic cancer. A PSA level above 50 ng/ml was never recorded for BPH, but lower levels can be due to either prostatic cancer or to BPH. Our data suggest that PSA is not a specific marker of prostatic cancer but increased serum PSA levels must draw the physician's attention to the possible presence of prostatic cancer.

Immunohistochemical estrogen receptor demonstration in the prostate and prostate cancer

Immunohistochemical investigations of human prostate and human prostate cancer were performed using two different monoclonal antibodies for the demonstration of estrogen receptors (ER). One marked the nuclear estrogen receptor protein (ERICAR, Abbott Laboratories), whereas the other one marked an estrogen receptor-associated cytoplasmic protein (ER-D5 kit, Amersham Buchler). 12 transurethral resection specimens with benign prostatic hyperplasia and 10 prostatic carcinomas were investigated by ERICA. Only in 1 specimen was a focally ERICA-positive basal cell hyperplasia found. The ER-D5 kit yielded a constantly positive reaction of stromal cells, especially smooth muscle cells. Basal cell hyperplasia and squamous metaplasia, alterations which can occur during estrogen application, were always strongly ER-D5-positive. Eleven (13.4%) out of 82 prostate carcinomas were focally positive. The staining results with ER-D5 are in good accordance with biochemical estrogen receptor investigations which demonstrated the estrogen receptors especially in the fibromuscular stroma. Furthermore, the results show that therapeutically applied estrogens do not directly inhibit the growth of prostatic carcinoma, however, the effect is an indirect one by suppressing androgen synthesis of the testis. The different staining results with ER-D5 and ERICA can be explained by the low ER concentration of prostate, the concentration is evidently below the limits of detectability with ERICA.

Immunocytochemical localization of polyamines in normal and neoplastic cells. Comparisons to the formaldehyde-fluorescamine and o-phthalaldehyde methods

Polyamines are low molecular weight organic cations, necessary for cell proliferation and implicated in numerous biochemical events. Their light microscopical distribution has previously been studied by the use of two fluorescence cytochemical methods. With the aid of an antibody recognizing the two main polyamines, spermidine and spermine, we now report on their immunocytochemical localization in animal tissues. Polyamine immunocytochemistry was found to require very well controlled conditions of fixation in order to prevent diffusion, loss and redistribution of endogenous polyamines. Moreover, in certain cellular compartments, polyamine immunoreactivity was masked by proteins, necessitating proteolytic pretreatment of sections prior to staining. The fluorescence cytochemical methods, employing low molecular weight reagents, did not require such unmasking. The results of the optimized immunocytochemical procedure were in complete agreement with the results obtained by the fluorescence cytochemical methods. Although fluorescence cytochemistry, is simpler and quicker to perform than immunocytochemistry, the latter technique may be extended to studies of polyamines at the ultrastructural level.

Actions and interactions of estradiol and retinoic acid in mouse anterior prostate gland

Experiments were designed to define the ability of retinoic acid to block the estrogen-induced metaplasia in the mouse anterior prostate gland (coagulating gland), and to elucidate some of the biochemical correlates of the actions and interactions of these two compounds. In castrated mice, the estrogen-induced metaplasia of epithelial cells consisted of multi-layered, nonpolarized cells, which accumulated to fill the lumen of the acini. Retinoic acid had no discernable effect on epithelial morphology of castrates, but significantly reduced the estrogen-induced metaplasia. Likewise, the estrogen-induced increases in the prostatic wet weight, ratio of ribonucleic to deoxy ribonucleic acids (RNA/DNA) and glycosyltransferases, as well as the decreases in 21,000 and 28,000 Mr soluble proteins were prevented by retinoic acid; the retinoid had no effect on these various parameters when administered alone to castrates. In contrast, the cyclic 3',5'-adenosine monophosphate (cAMP)-dependent phosphorylations at 16,000, 18,000, and 25,000 Mr and the activities of the type II cAMP-dependent kinase were uniformly reduced by both estradiol and retinoic acid. Tests of the action of the anti-estrogen LY-156758 on estrogen and retinoid effects showed that for those parameters on which retinoic acid was anti-estrogenic, LY-156758 was also anti-estrogenic. However, the qualitatively similar effects of retinoic acid and estradiol, which were confined to selected aspects of protein phosphorylation, were not antagonized by LY-156758. It is concluded that in the mouse anterior prostate, retinoic acid has both anti-estrogenic and estrogenic actions, and the latter may occur independently of the estrogen receptor.

Identification and characterization of alpha 1 adrenergic receptors in the canine prostate using [125I]-Heat

We have recently utilized radioligand receptor binding methods to characterize muscarinic cholinergic and alpha adrenergic receptors in human prostate adenomas. The primary advantages of radioligand receptor binding methods are that neurotransmitter receptor density is quantitated, the affinity of unlabelled drugs for receptor sites is determined, and receptors can be localized using autoradiography on slide-mounted tissue sections. Recently, [125I]-Heat, a selective and high affinity ligand with high specific activity (2200 Ci/mmole) has been used to characterize alpha 1 adrenergic receptors in the brain. In this study alpha 1 adrenergic receptors in the dog prostate were characterized using [125I]-Heat. The Scatchard plots were linear indicating homogeneity of [125I]-Heat binding sites. The mean alpha 1 adrenergic receptor density determined from these Scatchard plots was 0.61 +/- 0.07 fmol/mg. wet wt. +/- S.E.M. The binding of [125I]-Heat to canine prostate alpha 1 adrenergic binding sites was of high affinity (Kd = 86 +/- 19 pM). Steady state conditions were reached following an incubation interval of 30 minutes and specific binding and tissue concentration were linear within the range of tissue concentrations assayed. The specificity of [125I]-Heat for alpha 1 adrenergic binding sites was confirmed by competitive displacement assays using unlabelled clonidine and prazosin. Retrospective analysis of the saturation experiments demonstrated that Bmax can be accurately calculated by determining specific [125I]-Heat binding at a single ligand concentration. [125I]-Heat is an ideal ligand for studying alpha 1 adrenergic receptors in the prostate and its favorable properties should facilitate the autoradiographic localization of alpha 1 adrenergic receptors in the prostate.

Characteristics of prostate-derived growth factors for cells of the osteoblast phenotype

We examined the characteristics of mitogens extracted from human benign prostatic hyperplasia and prostatic adenocarcinoma tissue. Although mitogens for fetal rat skin fibroblasts as well as for rat calvarial osteoblasts and osterosarcoma cells were found, distinct entities that acted selectively in cells of the osteoblast phenotype could be obtained by sequential reverse-phase high performance liquid chromatography. Two peptides with apparent molecular weights of 10,000 and 13,000 D were derived from hyperplastic tissue, whereas a single moiety of 10,000 D was obtained from malignant tissue. These entities increased cell numbers and alkaline phosphatase activity in osteoblastlike cells consistent with effects on both growth and differentiation. Prostatic peptides did not stimulate adenylate cyclase in osteosarcoma cells. Mitogenic activity selective for osteoblastlike cells was identified in postpubertal but not prepubertal normal prostate. The results demonstrate the existence of osteoblastic growth factors in prostatic tissue whose presence may accompany postpubertal development.

Immunohistochemical localization of a prostatic secretory protein of 94 amino acids in normal prostatic tissue, in primary prostatic tumors and in their metastases

Using the immunoperoxidase technique, we have studied in normal, hyperplastic and adenocarcinomatous prostates the tissue localization of an abundant 94 amino acid protein secreted by prostatic epithelial cells. In normal and hyperplastic prostates, strong immunoreactivity was found exclusively in glandular epithelial cells. No reaction was observed over the stroma. In well differentiated adenocarcinoma, the acinar cells were generally stained less intensely than in benign prostatic hyperplasia while in poorly differentiated tissue, strongly positive immunoperoxidase staining was found in some cancer cells scattered in the stroma. All prostatic cancer tissues examined (N = 21), with the exception of one, exhibited at least a few positive immunoreactive areas for the 94 amino acid secretory protein. In addition, immunoperoxidase staining was observed in lung and bone marrow metastases respectively in two patients with prostatic carcinoma. All other normal tissues and non-prostatic cancers studied to date were negative. These results suggest that this new marker could be a useful addition to prostatic acid phosphatase and prostate specific antigen.

Identification of glutathione S-transferase Yb1 mRNA as the androgen-repressed mRNA by cDNA cloning and sequence analysis

Androgens, while stimulating the growth of the rat ventral prostate, can also repress the levels of a limited number of mRNAs. The cDNA for one of the androgen-repressed mRNAs has been identified by nucleotide sequence analysis as coding for the glutathione S-transferase Yb1 subunit. The prostate cDNA is 1071 nucleotides long, and only 2 or 4 bases of this sequence do not match the two published sequences of the cDNA for the Yb1 subunit of rat liver glutathione S-transferase. The amino acids in the protein encoded by the prostate cDNA matched completely with that for one of the liver cDNAs and differ with the other cDNA only in two of 218 amino acids. The identification of the androgen-repressed mRNA as a glutathione S-transferase subunit may indicate that some of the cellular actions of the enzyme may be important in the control of androgen-dependent growth of the prostate. Since Yb forms of the transferases have been colocalized with uridylic acid-rich small nuclear RNAs at interchromatinic regions of the cell nucleus, autoregulation of prostate growth by androgens may be carried out through the modulation of RNA production or processing in this target organ.

Application of high-performance liquid chromatofocusing to the study of prostatic androgen receptors. Effect of stabilizing agents on the heterogeneity of receptor structure

Cytosolic androgen receptors from normal rat prostate were analyzed by high-performance liquid chromatofocusing. Two ion-exchange columns, AX-300 and AX-500, and two equilibration systems, Tris-HCl and imidazole-HCl, were used. pH gradients ranged between 8.3 and 3.5 for Tris-HCl and from 7.7 to 3.5 for imidazole-HCl. In the absence of sodium molybdate and inhibitors of proteolytic enzyme, six specific radioactive fractions (pH: 7.9, 7.7, 7.0, 5.1, 4.7 and 4.4) were eluted from AX-300 equilibrated with Tris-HCl in a ratio of 28:20:52 for acidic, intermediary and basic forms, respectively; similar results were obtained with AX-500 although this column was less effective in resolving basic forms of the receptor. The buffering capacity of imidazole-HCl was lower than that of Tris-HCl, resulting in a steeper elution pH profile. The resolution between acidic and basic forms was thus diminished and only four specific radioactive fractions at pH 7.2, 7.1, 6.5 and 3.6, were observed on AX-500 in a ratio of 23:10:67 for acidic, intermediary and basic forms. In the presence of sodium molybdate, two acidic fractions were found with Tris-HCl at pH 4.3 and 4.7 (47%) on AX-300, whereas the radioactivity of fractions at pH 7.0 and 5.1 (32%) was considerably lowered and intermediary forms remained unchanged (21%). With imidazole-HCl on AX-500, the peak at pH 7.2 disappeared and the acidic form shifted from pH 3.6 to 4.3. In the presence of inhibitors of proteolytic enzyme and sodium molybdate, specifically bound radioactivity was found mostly in a broad acidic fraction (75%) at pH 4.5 on columns equilibrated with Tris-HCl; radioactivity at pH 7.6 disappeared completely but a small amount (15%) remained at pH 7.9. In imidazole-HCl, a main radioactive fraction was eluted at pH 7.1 and two other fractions were collected at pH 6.8 and 4.3 respectively. In conclusion, multiple forms of the rat prostate androgen receptor were evinced by high-performance liquid chromatofocusing. Tris-HCl proved to be a more efficient equilibration system than imidazole-HCl for the resolution of rat prostate cytosolic binding proteins. Under the experimental conditions used, sodium molybdate and inhibitors of proteolytic enzyme greatly favored the acidic form to the detriment of the intermediary and basic entities.

Prostatic growth factor: purification and structural relationship to basic fibroblast growth factor

Prostatic growth factor (PrGF) was purified from alkaline homogenates of human benign prostatic hyperplastic tissue by a combination of ammonium sulfate precipitation, heparin affinity chromatography, and cation-exchange chromatography. The 17,600-dalton, basic (pI 10.2) PrGF is related to basic fibroblast growth factor (bFGF) since antisera raised against synthetic peptides with sequence homologies corresponding to an internal peptide and amino- and carboxyl-terminal peptides of bFGF react with the growth factor. The growth factor appears larger than bFGF, suggesting that additional amino-terminal sequences may be present as a result of alkaline extraction in the presence of protease inhibitors.

High-performance liquid chromatographic determination of norfloxacin in human tissues and plasma with fluorescence detection

A high-performance liquid chromatographic method with fluorimetric detection is described for the quantitative determination of norfloxacin in renal and prostatic tissues and in plasma. It consists of tissue pretreatment, purification by solid-state extraction and separation and quantification by high-performance liquid chromatography on a C8 reversed-phase column. Analytical recoveries ranged from 95.2 to 97.6%. Within-day and between-day precision were assessed by analysing serum containing 50 and 500 ng/ml norfloxacin. At each concentration, the within-day precision was less than or equal to 3.6% (coefficient of variation; n = 10) and the day-to-day precision was less than or equal to 5.3% (n = 10). The limit of detection was 1 ng/ml.

Cysteine proteinase inhibitors in human and rat male sex glands

The testis and prostate of men had two types of cysteine proteinase inhibitors of different isoelectric point (pI = 4.5 and 6.3) and molecular masses (90,000 and 12,000). The seminal vesicle contained not only these two inhibitors but also a basic inhibitor with a pI = 9.5 and Mr 11,000. In rats, the inhibitors in the testis and prostate consisted of two types with pI values of 4.3 and 4.8 and Mr 90,000 for both. In addition to these two inhibitors, the seminal vesicle contained large amounts of two basic inhibitors with pI values of 7.5 and 8.3 and Mr of 11,000 for both. We suggest that the basic cysteine proteinase inhibitor found in semen might be excreted from or be modified in the seminal vesicle.

Isolation from human seminal plasma of an abundant 16-kDa protein originating from the prostate, its identification with a 94-residue peptide originally described as beta-inhibin

In addition to other known markers of the human prostate, it was shown that the prostatic fraction of the split ejaculate was rich in a 16-kDa protein with properties not described previously. This protein was purified from human seminal plasma using ammonium sulfate precipitation, DEAE-Sepharose CL-6B ion exchange chromatography, and gel filtration on Sephadex G-100. The purified protein showed a single prominent spot on two-dimensional gel electrophoresis. The sequence of the first 40 amino acids that could be positively identified was identical to that of a prostatic secretory protein of 94 amino acids (PSP94) previously designated as beta-inhibin. Antibodies produced in rabbits against the purified protein were used to develop a radioimmunoassay. These antibodies appeared to recognize only the NH2-terminal portion of the native molecule since they did not react with a synthetic peptide composed of the 28 C-terminal residues. The radioimmunoassay showed that the concentration of the protein was 1320 +/- 183 micrograms/ml in the seminal plasma of adult fertile men and 1134 +/- 136 micrograms/ml in vasectomized patients. In hypertrophic and adenocarcinomatous prostates, the concentrations were 326 +/- 156 and 104 +/- 23 micrograms/ml, respectively, while values were lower than 0.060 micrograms/ml in the testis, epididymis, vas deferens and liver. The blood plasma concentration was 0.019 +/- microgram/ml in 23 asymptomatic men 45 to 65 years old and 0.115 +/- 0.036 microgram/ml in eight patients with prostate cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

Localization of epidermal growth factor receptors in the human prostate by biochemical and immunocytochemical methods

The receptor for epidermal growth factor (EGF) was characterized in the particulate fraction from human benign prostatic hyperplasia (BPH) and was present in 85% of tissues analysed. The uptake of 125I-labelled EGF by BPH was dependent on both time and temperature, with maximum specific uptake achieved after incubation for 90 min at 37 degrees C. Binding characteristics revealed two classes of binding sites of higher (mean dissociation constant (Kd) +/- S.D. = 0.8 +/- 0.2 nmol/l) and lower (Kd = 7.6 +/- 2.8 nmol/l) affinities. Competition studies demonstrated the specificity of the receptor assay since the binding of labelled EGF was abolished with excess unlabelled EGF but not with excess unlabelled human GH, human insulin, venom nerve growth factor, human FSH, human LH and human prolactin. There was a complex biphasic relationship between specific binding and protein concentration in the range 0.1-8 mg/ml. Subcellular fractionation of BPH homogenates demonstrated that the bulk of the specific binding was confined to the 800 g (crude heavy pellet) and 15,000 g (mitochondrial pellet) fractions. The 105,000 g (microsomal pellet) and the 105,000 g (cytosol fraction) exhibited low and variable binding capacities for the growth factor. The presence of EGF receptor was also confirmed by immunocytochemical staining of frozen sections from BPH using monoclonal antibody specific for EGF receptors. A positive correlation between 125I-labelled EGF binding and the intensity of staining was found. The presence of a specific EGF-binding receptor protein in human BPH tissues suggests that EGF may play a role in the pathogenesis of human BPH.

[Effect of trans-4-hydroxy-3-methoxycinnamic acid (ferulic acid) on polyamine level in the rat ventral prostate]

Ferulic acid (FA) specifically inhibits the growth of the ventral prostate in rats not through antiandrogenic mechanisms (Saito et al. Experientia 35: 696, 1979). Levels of polyamines in the rat ventral prostate were determined before and after FA administration (10, 25 and 50 mg/kg BW, s.c., for 5 days). SD strain male rats, 5 approximately 7 weeks of age, were used. The ventral prostates were homogenized with 10% TCA and centrifuged. The supernatant was washed twice with diethylether, freeze-dried, and redissolved in distilled water. Then, the contents of putrescine, spermidine and spermine were measured by an isotachograph (LKB), using a leading buffer composed of 5 mM Ba(OH)2/15 mM valine, pH 9.94, and a terminating buffer composed of 20 mM triethylenediamine, pH 10.20. Total polyamines were reduced dose-dependently (12.12, 9.95, 9.10 and 7.74 nmol/mg wet tissue at 0, 10, 25 and 50 mg/kg FA, respectively). Spermidine was more sensitive to FA than spermine. According to the attitude of the Spermidine/Spermine ratio, the inhibition of ornithine decarboxylase by FA has been suggested.

Correlation of biochemical (receptors, endogenous tissue hormones) and quantitative morphologic (stereologic) findings in normal and hyperplastic human prostates

In previous light and electron-microscopic analyses human benign prostatic hyperplasia was shown to be predominantly a stromal disease; the aim of the present study was to correlate the stereological data with the levels of the endogenous tissue hormones (androgens, estrogens, progesterone) in normal (N) and hyperplastic human prostatic tissues (BPH). BPH tissue specimens were obtained by open prostatectomy (n = 25); normal prostatic tissue was obtained from kidney donors (n = 5). No statistically significant difference was found between normal and hyperplastic tissue. Testosterone BPH 0.69 +/- 0.44, N 0.25 +/- 0.12; 5 alpha-dihydrotestosterone BPH 7.0 +/- 2.9, N 4.2 +/- 0.7; progesterone BPH 0.059 +/- 0.022, N 0.058 +/- 0.005; estrone BPH 0.10 +/- 0.03, N 0.14 +/- 0.03; estradiol BPH 0.07 +/- 0.02, N 0.05 +/- 0.02; estriol BPH 0.02 +/- 0.01, N 0.04 +/- 0.02. Using a Spearman rank correlation coefficient a statistical analysis was performed for age, weight of the prostate, absolute stereological data and the endogenous prostatic hormones. As can be seen from the statistical analysis there is a poor correlation for 5 alpha-dihydrotestosterone and the amount of the glandular epithelium; otherwise no correlation of the endogenous tissue hormones with the stereological data investigated was found. These data show that the stromal overgrowth of benign hyperplasia is not reflected in the tissue hormone levels.

Prostatic spermine-binding protein. Cloning and nucleotide sequence of cDNA, amino acid sequence, and androgenic control of mRNA level

cDNA for mRNA of an androgen-dependent spermine-binding protein (SBP) of rat ventral prostate was cloned by inserting cDNA into a dG-tailed expression vector, pUC8, and screening the expression library with anti-SBP antibodies. Hybrid-selected translation using plasmid DNA from positive clones yielded a 34-kDa protein which was immunoprecipitated by affinity-purified anti-SBP antibodies. SBP mRNA is about 1260 bases long as measured by Northern blot hybridization. An amino acid sequence deduced from the nucleotide sequence of the cDNA was identical to an amino acid sequence found in SBP. SBP is extremely rich in acidic residues. Aspartic and glutamic acids, which make up about 33% of the total sequence, comprise 89 of a stretch of 126 amino acids at the carboxyl-terminal end. By dot hybridization analysis, SBP mRNA was not detected in rat liver, kidney, brain, submaxillary gland, or uterus. The prostate levels of SBP mRNA were measured by mRNA translation and dot hybridization. SBP mRNA level decreased to less than 20% of normal 2 days after castration of rats, and this decrease was reversed by 5 alpha-dihydrotestosterone injection into castrated rats.