Showing papers in "The Prostate in 1991"
TL;DR: Growth experiments with indomethacin, esculetin, and piroxicam, pharmacological inhibitors of eicosanoid biosynthesis with differing sites of action, indicated that human prostate cancer cell growth requires intact metabolic pathways for both leukotriene and prostaglandin production.
Abstract: Dietary fatty acids (FAs) may be involved in the carcinogenic process within the prostate gland and progression to clinically manifest disease. We have shown that growth of the androgen-unresponsive PC-3 human prostate cancer cell line is stimulated in vitro by the presence of linoleic acid (LA), an omega-6 polyunsaturated FA. The response was positively related to the FA concentration over the entire range examined (5-750 ng/ml). Conversely, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), two omega-3 FAs present in fish oils, inhibited PC-3 cell growth in a dose-dependent manner; both were equally effective, with an approximately 65% reduction in growth occurring at a concentration of 2.0 micrograms/ml (P less than 0.001). The DU 145 human prostate cancer cell line, which is also androgen-unresponsive, showed no growth response to LA and was less susceptible to growth inhibition when cultured in the presence of omega-3 FAs. Growth experiments with indomethacin, esculetin, and piroxicam, pharmacological inhibitors of eicosanoid biosynthesis with differing sites of action, indicated that human prostate cancer cell growth requires intact metabolic pathways for both leukotriene and prostaglandin production.
207 citations
TL;DR: The relative distribution pattern of the pan‐endocrine marker Chromogranin A (Chr A) and the proliferation‐associated Ki‐67 antigen was investigated and showed evidence of endocrine differentiation in all 15 prostatic adenocarcinomas.
Abstract: The relative distribution pattern of the pan-endocrine marker Chromogranin A (Chr A) and the proliferation-associated Ki-67 antigen was investigated in 20 prospectively sampled prostatectomy specimens. In cryostat sections, the Chr A immunoreactivity showed evidence of endocrine differentiation in all 15 prostatic adenocarcinomas. Nine tumors displayed a weak, 5 a moderate, and 1 adenocarcinoma a strong endocrine differentiation. These findings highlight the importance of endocrine differentiation in prostate malignancy that histologically resembles ordinary adenocarcinomas. The simultaneous demonstration of Ki-67 and Chr A revealed that in normal, hyperplastic, and neoplastic prostate tissue Chr A-positive cells were preferentially situated in proximity to Ki-67-labeled cells. This relative distribution pattern of both markers may indicate that endocrine cells are involved in controlling cell proliferation through a paracrine hormonal mechanism. However, an obvious correlation was not found between the degree of endocrine differentiation and proliferative activity in prostatic adenocarcinomas. Furthermore, a coexpression of Ki-67 and Chr A in the same (tumor) cells was not observed suggesting that the endocrine phenotype is only expressed in the G0 phase of the cell cycle as well as in normal, hyperplastic, and neoplastic conditions.
195 citations
TL;DR: It is hoped that this review will bring attention to the importance and urgency of elucidating and understanding the metabolic relationships associated with citrate production by normal and neoplastic prostate epithelial cells.
Abstract: Accumulation and secretion of extraordinarily high levels of citrate are principal functions of the prostate gland of humans and other animals. To achieve this, prostate secretory cells must possess unique metabolic relationships which distinguish them from virtually all other cells. Furthermore, citrate metabolism is markedly altered in benign prostatic hyperplasia (BPH) and in prostatic carcinoma (CA). This review assimilates existing information and presents current concepts related to 1) the pathway of metabolism associated with net citrate production, 2) the involvement of transporting mechanisms associated with citrate secretion, 3) energy implications of citrate production, 4) altered metabolic relationships in BPH and CA, and 5) the importance of citrate relationships as biochemical markers for characterizing prostate secretory epithelial cells. It is hoped that this review will bring attention to the importance and urgency of elucidating and understanding the metabolic relationships associated with citrate production by normal and neoplastic prostate epithelial cells. Research in these areas has been severely neglected despite the fact that the combined incidence of BPH and CA constitutes the most prevalent neoplastic disease among men.
178 citations
TL;DR: Concepts of the pathogenesis of prostatic neoplasms are presented based on hormonal, metabolic, and homologous relationships associated with citrate production and the urgency and necessity for research relating to all aspects of prostatecitrate production in normal and pathological prostate are emphasized.
Abstract: A unique and major function of prostate secretory epithelial cells is to synthesize, accumulate, and secrete extraordinarily high levels of citrate. This function is regulated by testosterone and by prolactin. Concepts of the mechanisms of hormonal regulation are presented. The relationship of testosterone and prolactin to the origin and homologies of different prostate cell lines is described. The metabolic differentiation of citrate and non-citrate producing prostate secretory epithelial cells is discussed. Concepts of the pathogenesis of prostatic neoplasms are presented based on hormonal, metabolic, and homologous relationships associated with citrate production. Characterization of normal and neoplastic secretory epithelial cells by their citrate function is emphasized. The urgency and necessity for research relating to all aspects of prostate citrate production in normal and pathological prostate are emphasized.
95 citations
TL;DR: The results suggest that 111In‐CYT‐356 can be safely administered to patients with prostatic carcinoma and that further clinical investigation of this agent is warranted.
Abstract: A phase 1 study was conducted with the investigational immunoscintigraphic agent, 111In-CYT-356, a radiolabeled, site-specific immunoconjugate of monoclonal antibody 7E11-C5.3, in 40 patients with prostatic carcinoma and known distant metastases. Each patient received a single intravenous infusion of CYT-356 (dose range, 0.1-5 mg) radiolabeled with approximately 5 mCi of 111In. None of the patients experienced adverse reactions. One patient who received a 5-mg dose developed antibodies to the CYT-356 immunoconjugate. 111In-CYT-356 immunoscintigraphy detected bony metastases in 21 of 38 patients (55%), including 12 of 14 (86%) receiving concomitant hormonal therapy, and soft tissue lesions in four of six patients (67%). Antibody imaging detected occult lesions in the bony pelvis and lumbar spine, which were confirmed by follow-up imaging tests, in one patient. Higher CYT-356 doses may clear the blood pool more slowly. These results suggest that 111In-CYT-356 can be safely administered to patients with prostatic carcinoma and that further clinical investigation of this agent is warranted.
92 citations
TL;DR: In neonatally estrogenized (neoDES) mice, responses to 5α‐dihydrotestosterone in terms of nuclear 3H‐thymidine labelling were altered concomitantly with the inhibition of growth and were in accordance with changes in the relative volumes of epithelium, glandular lumina, and interacinar stroma.
Abstract: Neonatal estrogenization of the mouse with diethylstilbestrol resulted in time-of-exposure and dose-dependent inhibition of the growth of the prostatic lobes observed at the age of 2 mon. The critical time was the days 1-6 of postnatal life. In neonatally estrogenized (neoDES) mice, responses to 5 alpha-dihydrotestosterone in terms of nuclear 3H-thymidine labelling were altered concomitantly with the inhibition of growth and were in accordance with changes in the relative volumes of epithelium, glandular lumina, and interacinar stroma. Secondary estrogen treatment of neoDES mice with 17 beta-estradiol did not increase 3H-thymidine labelling in the prostate of control or neoDES mice. However, it induced squamous epithelial metaplasia in periurethral collecting ducts and proximal parts of coagulating glands of neoDES animals. In control mice only slight epithelial hyperplasia could be observed after similar treatment. Estrogen receptors, located immunocytochemically in nuclei of stromal cell, corresponded with the sites of increased estrogen sensitivity, observed as metaplastic transformation. When the neoDES animals aged, epithelial hyperplasia and dysplasia could be observed at distinct prostatic sites, ie, the periurethral collecting ducts and the coagulating glands and periurethral glands, and stromal inflammation become more extensive. Almost identical location of the epithelial changes and the altered estrogen response is suggestivemore » of causal relationship.« less
87 citations
TL;DR: Results indicate that antibodies to specific cytokeratin polypeptides can be used not only to differentiate between prostatic basal and luminal cells but also to study the biological processes of prostatic organogenesis and carcinogenesis.
Abstract: The purpose of the present study was to identify cytokeratin polypeptides that are specifically associated with the basal and luminal epithelia of the human prostate. This aim was accomplished by immunohistochemical and immunoblot analysis of human prostate using cytokeratin-specific monoclonal antibodies. In immunohistochemical studies, monoclonal anticytokeratin 8.12 exhibited immunoreactivity with the basal, but not luminal, epithelial cells of fetal, juvenile, normal adult, and hyperplastic prostate. The 8.12 antibody did not stain prostate cancer tissues. Epithelia of 30 and 36 week fetal prostate contained only basal cells whereas both luminal and basal cells were noted in 7 month and 1 year old juvenile prostate. This finding suggests a stem cell function for the prostatic basal cells. Immunoblot analysis of proteins separated by two-dimensional electrophoresis showed that cytokeratins 5 and 15 were basal-cell-specific cytokeratins that were absent from prostatic carcinoma while cytokeratins 8 and 18 appear to be luminal-cell-specific. These results indicate that antibodies to specific cytokeratin polypeptides can be used not only to differentiate between prostatic basal and luminal cells but also to study the biological processes of prostatic organogenesis and carcinogenesis.
85 citations
TL;DR: The presence of the IGF‐I receptor and the absence of IGF‐II and insulin receptors are discussed in relation to the capacity of PA‐III cells to produce bone lesions on the L‐W rat.
Abstract: Four transplantable cell lines (PA-I, II, III, and IV) derived from four Lobund-Wistar (L-W) rats that manifested spontaneous prostate cancer have demonstrated metastatic capacity in visceral organs. Interestingly, PA-III cells, when deposited over the scapula or calvarium of the Lobund-Wistar rat, could produce lytic and blastic reactions on rat skeleton. Since growth factors and growth factor receptors have been implicated in bone remodeling, cancer biology, and metastatic growth of cancer cells, we have examined 1) the effects of insulin and insulin-like growth factors (IGF-I and IGF-II) on the proliferation of PA-III cells; and 2) the presence of specific receptors for these peptides. IGF-I (0.5 to 100 ng/ml), IGF-II (0.5 to 100 ng/ml), and insulin (0.5 to 10 micrograms/ml) stimulated tritiated thymidine uptake and increased the number of PA-III cells in culture. Receptor studies demonstrated the presence of specific bindings sites for IGF-I and II but not for insulin. The number and affinity of the receptor sites were: IGF-I (nb = 675 fmol/100 g protein, Kd = 0.56 nmol) and IGF-II (nb = 225 fmol/100 g protein, Kd = 0.71 nmol). Molecular characterization of IGF binding sites by polyacrylamide gel electrophoresis under denaturing conditions indicated only the presence for the type I IGF receptor. The presence of the IGF-I receptor and the absence of IGF-II and insulin receptors are discussed in relation to the capacity of PA-III cells to produce bone lesions on the L-W rat.
84 citations
TL;DR: The results indicate that the differentiated properties of prostatic epithelial cells are promoted by cultivation on reconstituted basement membrane in the presence of DHT and stromal cell conditioned medium.
Abstract: Prostatic epithelial cells undergo rapid proliferation and lose their ability to synthesize and secrete prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) under standard tissue culture conditions. Herein, we compared the morphology, growth, secretory activity, and intermediate filament expression of human prostatic epithelial cells cultured on either standard tissue culture plastic or reconstituted basement membrane. Epithelial cells grown on plastic exhibited a 10-fold increase in proliferation and a higher percentage of cells in the S-phase of the cell cycle compared to cells cultured on basement membrane. However, cells grown on basement membrane secreted markedly higher levels of PSA and PAP. The basement membrane-induced enhancement of secretory activity was potentiated by dihydrotestosterone (DHT) and prostate stromal cell conditioned medium. Morphological studies showed that cells plated on basement membrane formed organoid-like clusters and maintained several aspects of differentiated epithelium including abundant secretory vesicles, microvilli, and desmosomes with associated cytoskeletal elements. Cultivation of epithelial cells on basement membrane components also suppressed the expression of vimentin, a mesenchymal intermediate filament polypeptide. However, cytokeratin expression was abnormal in cells grown on either surface. These results indicate that the differentiated properties of prostatic epithelial cells are promoted by cultivation on reconstituted basement membrane in the presence of DHT and stromal cell conditioned medium.
73 citations
TL;DR: It is concluded that DU145 cell growth is regulated by an EGF‐mediated autocrine loop.
Abstract: The DU145 human prostate cancer cell line possesses epidermal growth factor (EGF) receptors and synthesizes both EGF and the related polypeptide transforming growth factor-alpha (TGF-alpha). A monoclonal antibody to the EGF receptor was used to determine whether these characteristics were indicative of a functional autocrine regulatory system. This antibody competed effectively with [125I]EGF for binding to DU145 cell binding sites over a 1 x 10(-11) to 1 x 10(-7) M concentration range, and did so with a capability similar to that of the two natural ligands. It inhibited growth of these cells in both 3% fetal bovine serum-supplemented and serum-free medium; in experiments with incubation times of 3-5 days there was a 45-50% reduction in cell number. Growth suppression by the EGF receptor blockade of cells plated at a density of 1.5 x 10(4) cells/ml/well was reversed competitively by the addition of EGF to the medium; 0.3 nM completely eliminated the inhibitory effect of a 1 x 10(-9) M antibody concentration. It is concluded that DU145 cell growth is regulated by an EGF-mediated autocrine loop.
69 citations
TL;DR: Results indicate 1) α 1 receptor agonists can cause contraction of smooth muscle to expel fluid from the rat prostate, 2) carbachol induces prostatic secretion through a mechanism other than contraction of gland, and 3) testosterone has a primary role in controlling prostatic size.
Abstract: To study the neuronal and hormonal control of prostatic secretion, the prostatic urethra was cannulated in urethane anesthetized rats. The volume of prostatic secretion was measured following infusion of cholinergic and adrenergic agonists in intact animals. Prostatic secretion was elicited by norepinephrine, phenylephrine, and carbachol; but not by clonidine, isoproterenol, pilocarpine, or acetylcholine. Phenylephrine and norepinephrine infusions caused a high initial rate of secretion, which then declined rapidly. Carbachol infusion, in contrast, produced a low but constant rate of secretion that was maintained for up to 1 hour. Histological examination of the prostate revealed contraction of smooth muscle surrounding prostatic ducts after infusion of phenylephrine and norepinephrine, but not carbachol. Prostatic secretion was also measured in castrated rats supplemented with various doses of testosterone. Testosterone exerted a dose dependent control of prostatic weight and secretory volume. These results indicate 1) α 1 receptor agonists can cause contraction of smooth muscle to expel fluid from the rat prostate, 2) carbachol induces prostatic secretion through a mechanism other than contraction of gland, and 3) testosterone has a primary role in controlling prostatic size.
TL;DR: The pedigrees of three families with four pathologically confirmed cases of cancer of the prostate in each family suggest that a familial predisposition to prostatic cancer may become apparent in later decades of life.
Abstract: Cancer of the prostate is one of the most common cancers among males in North America. Although some causative factors have been suggested by several surveys, the etiology of this common cancer is poorly understood. In a case-control study of prostatic cancer in Greater Montreal, 21 of 140 patients with prostatic cancer (15.0%) gave a positive family history of the same cancer, as compared with two cases among 101 (2.0%) population-based controls. This indicates about an eightfold difference in occurrence of cancer of the prostate among first-degree family members of the case group with an odds ratio (OR) of 8.7 and 95% CI, 2.00-38.17. In this report we present the pedigrees of three families (two cases and one control) with four pathologically confirmed cases of cancer of the prostate in each family. This data suggest that a familial predisposition to prostatic cancer may become apparent in later decades of life. In these family aggregations, in addition to the genetic factors, environmental factors may also play an important role in the etiology of the same cancer among family members.
TL;DR: The failure of MK‐906 to influence tumor growth in the TP‐treated castrates strongly suggests that the R‐3327 tumor can respond to testosterone directly, and is unlikely to be affected by a pure 5α‐reductase inhibitor such as MK‐ 906.
Abstract: Male rats bearing implants of the Dunning rat prostatic carcinoma, R-3327, were used in a 42-day study to determine the effect of castration or orally administered flutamide (FL), DES (diethylstilbestrol) or the 5 alpha-reductase inhibitor, MK-906, on the growth of this androgen-responsive cancer. The rate of growth and final weights of the tumor and the ventral prostate (VP) were all reduced (P less than 0.05) by castration. Flutamide (25 mg/kg/day) significantly decreased tumor and VP weights in intact rats and castrates given 100 micrograms/day (SC) of testosterone propionate (TP) or dihydrotestosterone propionate (DHTP). It also significantly retarded tumor growth rate in TP- or DHTP-treated castrates and was marginally effective in intact animals. DES (100 micrograms/kg/day) reduced (P less than 0.05) tumor and VP weights of intact rats but did not significantly affect tumor growth rate or weight in castrates given TP or DHTP. These results indicated that the effect of DES on tumor growth is caused by its inhibition of the secretion or release of the gonadotropins necessary for testicular androgen production. MK-906 (25 mg/kg/day) affected neither the gross nor the histomorphology of the tumor in intact rats or castrates given TP or DHTP. Further, it caused no histological changes in the testes of intact rats. It did, however, significantly reduce VP weight in intact animals and TP-treated castrates but not in those given DHTP. This illustrates that the anti-androgenicity of MK-906 stems from its inhibition of DHT formation. The failure of MK-906 to influence tumor growth in the TP-treated castrates strongly suggests that the R-3327 tumor can respond to testosterone directly. If that is true, then its growth is unlikely to be affected by a pure 5 alpha-reductase inhibitor such as MK-906. In ancillary experiments, tumors from MK-906-treated animals were found to have reduced levels of DHT and, when assayed in vitro, to have a reduced capacity to convert [3H]-T to [3H]-DHT.
TL;DR: Heterogeneity in u‐PA expression was shown by the fibrin lysis assay, immunohistochemistry, and dual parameter flow cytometry indicating the presence of phenotypically divergent cell populations.
Abstract: Plasminogen activators (PA), particularly the lower Mr urokinase (u-PA) type, have been associated with tumor cell invasion and metastasis. We have examined the expression of PA by two human prostate cancer cell lines (PC-3 and DU-145) using functional and immunologic techniques. The culture media and cell extracts of the more aggressive PC-3 cell line contained more than two-fold greater PA activity than the relatively indolent DU-145 cell line. Zymographic studies identified the PA expressed as u-PA. PC-3 cells expressed an additional lower molecular weight form of u-PA not noted in DU-145 cells. Heterogeneity in u-PA expression was shown by the fibrin lysis assay, immunohistochemistry, and dual parameter flow cytometry indicating the presence of phenotypically divergent cell populations. Increased u-PA expression may identify those tumor cells that possess aggressive biological potential.
TL;DR: It appears that the assessment of the NSE serotest, despite its minimal value in the overall tumor staging and monitoring, might furnish the decision‐making step related to the treatment of aggressive prostate cancer with an additional and powerful tool.
Abstract: A quadruple tumor marker serotest assay (neurone-specific enolase, NSE, prostate-specific antigen, PSA, prostatic acid phosphatase, PAP, and carcino-embryonic antigen, CEA) was performed on sera from both 63 patients with untreated prostate cancer and 135 patients treated with orchiectomy, flutamide, diethylstilbestrol (DES), cyproterone acetate (CPA), and Estracyt. In untreated patients with local tumor elevated blood NSE concentrations were found more frequently (10/35, 28.6%) than in untreated subjects with disseminated disease (3/28, 10.7%). Elevated NSE values were measured more frequently in nonresponders to therapy 10/46 (21.7%), than in responders during prostate cancer partial remission (2/89, 2.2%). In none of NSE-positive neoplasms a small cell prostate cancer has been histologically detected. Many of NSE-positive tumors are also closely associated with elevated blood CEA values. The applied anticancer drugs were inefficient in the normalization of neither one from the pair of elevated NSE and CEA concentrations (regardless of the numerical values of the other two markers, PSA and PAP), but their values were found to decline occasionally only after surgical treatment. In patients with raised PSA, PAP, and CEA levels but with a normal NSE value, the application of the same treatment strategies was in the most of subjects sufficient to provoke either temporary or even lasting tumor response to therapy. Hence, it appears that the assessment of the NSE serotest, despite its minimal value in the overall tumor staging and monitoring, might furnish the decision-making step related to the treatment of aggressive prostate cancer with an additional and powerful tool.
TL;DR: An increased number of HLA class II‐positive interstitial cells in low‐grade carcinomas, corresponding mostly to macrophages are Documented.
Abstract: We have investigated Langerhans cell (LC) distribution in 38 prostatic carcinomas, of various degrees of differentiation, by immunohistochemistry with a polyclonal anti-S-100 serum, furthermore evaluating the expression of HLA class II-DR by neoplastic cells using a monoclonal antibody (MoAb) that reacts with a monomorphic determinant in formalin-fixed paraffin-embedded tissue. Antiserum to S-100 protein identified LCs mostly in carcinomas ranging from grade 1 to grade 2, while LCs were inconspicuous in grade 4 and virtually absent in grade 5 cancers. Moreover, sections stained with the anti -HLA-DR MoAb displayed an immunoreactivity, both cytoplasmic and apical, especially confined to neoplastic glands of low grade (1–2) carcinomas. Although we did not find a direct correlation between the two parameters under investigation and lymphoid infiltrate, we were able to document an increased number of HLA class II-positive interstitial cells in low-grade carcinomas, corresponding mostly to macrophages.
Our results indicate that LC number is inversely correlated to the histopathological grade and directly to the expression of HLA class II-DR molecules by tumor cells; we believe that this might be important in understanding the more favorable biological behavior of low-grade prostate carcinomas as opposed to the higher grades, since LCs and HLA class II molecules may provide a means of eliciting the immune response, both LCs and epithelial cells expressing HLA class II molecules being capable of direct antigen presentation to immune cells. In this context macrophages might play a primary role in controlling tumor progression. To the best of our knowledge this is the first time that an attempt is made to correlate LCs and HLA class II expression to histopathological grading of prostatic carcinomas. We would also suggest that the presence of LCs and HLA class II molecules, either singly or in combination, in carcinoma of the prostate represents a good prognostic indicator, being constantly associated with the clinically less aggressive low-grade tumors. The evaluation of these two parameters might prove useful in the assessment of intermediate grades where no valid histologic criteria have been found to predict the clinical course of the disease.
TL;DR: The present review provides further evidence that selective alpha1 blockers are effective and safe for the treatment of symptomatic BPH and the improvements in the outcome parameters (symptom scores and urinary flow rates) are clinically and statistically significant.
Abstract: At least 16 clinical investigations have documented the effectiveness of alpha blockade for BPH. In the present review, four clinical studies evaluating the efficacy and safety of terazosin, a selective long-acting alpha 1 blocker, for symptomatic BPH are reviewed. The unique features of these clinical investigations are: the study designs established detailed inclusion and exclusion criteria, the outcome assessments were based upon quantitative outcome parameters, large cohorts of homogeneous patients were enrolled, and appropriate statistical methods were utilized. The dose of terazosin was titrated to maximal doses ranging between 5-20 mg. Only four of the 163 patients developed orthostatic hypotension. Overall, the peak and mean uroflow rates increased 50% and 46%, respectively (P less than 0.001). The cumulative improvement in the mean obstructive, irritative, and total symptom scores was 67%, 35%, and 54%, respectively (P less than 0.001). The present review of terazosin in males with symptomatic BPH supports the following conclusions: (1) the dose of terazosin can be safely titrated to 10 mg in normotensive and hypertensive patients with symptomatic BPH; (2) the adverse events associated with doses of terazosin up to 10 mg are relatively mild and reversible; and (3) the improvements in the outcome parameters (symptom scores and urinary flow rates) are clinically and statistically significant. Although the ultimate role of terazosin for symptomatic BPH will be determined by multi-center randomized placebo-controlled studies, the present review provides further evidence that selective alpha 1 blockers are effective and safe for the treatment of symptomatic BPH.
TL;DR: Immunohistochemical study demonstrated that MT was localized in the cytoplasm, nuclei of glandular epithelia, and secretory products, and a positive immunoreaction was strong in PZ and weak in CZ.
Abstract: Metallothionein (MT) in the human prostate gland was examined. Prostatic tissues were obtained from patients of urinary bladder cancer who had received radical cystoprostatectomy. MT content was 99.3 micrograms/g wet tissue (w.t.) in the peripheral zone (PZ), 12.0 micrograms/g w.t. in the preprostatic region (PR), 7.3 micrograms/g w.t. in the central zone (CZ), 6.8 micrograms/g w.t. in the anterior fibromuscular stroma, and 29.5 micrograms/g w.t. in benign nodular hyperplasia (adenoma) by radioimmunoassay. Immunohistochemical study demonstrated that MT was localized in the cytoplasm, nuclei of glandular epithelia, and secretory products. In general, a positive immunoreaction was strong in PZ and weak in CZ. It is considered that glandular epithelial cells in PZ, PR, CZ, and adenoma may react differently to heavy metals, e.g., zinc and cadmium.
TL;DR: A comparative study on immunocytochemical localization, de novo biosynthesis, and hormonal modulation of FSH was carried out in the prostates of man, monkey, dog, guinea pig, hamster, rat, and mouse as mentioned in this paper.
Abstract: A comparative study on the immunocytochemical localization, de novo biosynthesis, and hormonal modulation of follicle-stimulating hormone (FSH) was carried out in the prostates of man, monkey, dog, guinea pig, hamster, rat, and mouse. FSH was localized in the cytoplasm of the prostatic epithelial cells. In some specimens, staining was also observed in the nucleus. Both pituitary as well as prostatic FSH were coeluted on a Sephadex G-100 column and high-performance liquid chromatography (HPLC) indicating physicochemical similarities of FSH in both the tissues. Surprisingly, the modulation of pituitary and prostatic FSH by inhibin and its related peptides were comparable. The intensity and grandularity of FSH staining was stronger in the case of benign prostatic hyperplasia as compared with normal prostatic specimens. In view of the well-known effects of FSH on the cellular growth, differentiation, and function of gonadal tissues, a similar role for FSH in pathophysiology of prostate is postulated.
TL;DR: It is concluded that cytokine combination treatment may provide a new approach in the treatment of hormone‐escaped prostatic tumors with significant antiproliferative effects against the PC3 tumor, but not against the DU145 tumor.
Abstract: We have investigated the antiproliferative effects of recombinant human alpha- and gamma-Interferon (IFN) and recombinant human Tumor Necrosis Factor alpha (TNF) against the hormone-independently growing PC3 and DU145 prostatic tumor lines. Subcutaneous, peritumoral administration of the drugs was started 24 hours after subcutaneous implantation of 1-2 mm3 tumor pieces. IFN was given three times per week and TNF five times per week. IFN-alpha (dose-range 0.5-5 ng/gram bodyweight) had significant growth-inhibiting effects against the PC3 tumor, but showed no significant antitumor effects against the DU145 tumor. IFN-gamma monotherapy (dose-range 8-80 ng/gram bodyweight) was less effective than IFN-alpha. 500 ng/gram TNF produced growth inhibition of both tumors, whereas the lower dose (50 ng/g) was only effective against the PC3 tumor. IFN-alpha and -gamma combination treatment had significant antiproliferative effects against the PC3 tumor, but not against the DU145 tumor. Combinations of IFN-alpha and TNF were very effective against both xenografts; some combinations resulted in complete growth inhibition. IFN-gamma and TNF combinations also showed significant antitumor effects against both tumor lines. We therefore conclude that cytokine combination treatment may provide a new approach in the treatment of hormone-escaped prostatic tumors.
TL;DR: It is concluded that ZOLADEX® is an alternative to DES in patients with stage D2 prostate cancer and was better tolerated than DES.
Abstract: This open, prospective study was conducted to compare ZOLADEX® (goserelin acetate implant) and diethylstilbestrol (DES) in the treatment of stage D2 prostate cancer. Sixtyseven patients were allocated to receive 3.6 mg of ZOLADEX® every 28 days by subcutaneous injection (n=48) or 3 mg of DES daily by oral administration (n=19). Median serum levels of testosterone were reduced to castrate levels (<50 ng/dl) within one month of therapy in each group and remained so for up to 120 weeks. According to modified criteria of the National Prostatic Cancer Project, 88% of patients in the ZOLADEX® group and 84% in the DES group were objective responders. Time to treatment failure and survival were not significantly different between groups, yet the confidence limits for the hazard ratios were wide. ZOLADEX® was better tolerated than DES. We conclude that ZOLADEX® is an alternative to DES in patients with stage D2 prostate cancer.
TL;DR: The results suggest that voltagegated calcium channels exist in both DU 145 cancer cells and fibroblasts, however, verapamil, in contrast to 1 BR, failed to block these channels in DU 145 cells.
Abstract: Calcium and calmodulin play significant roles in DNA synthesis and cell proliferation. In this work the effects of verapamil, trifluoperazine, and tamoxifen on 45Ca uptake and cell growth in human prostatic tumor cells (DU 145) and human fibroblast cells (1 BR) were studied. Although the maximum proliferation was achieved at a concentration of around 2 mM CaCl2 in both DU 145 and 1 BR, growth of DU 145 cells was considerably greater than 1 BR at all calcium concentrations (0.1-4 mM). Calcium uptake experiments, using 45Ca, revealed that the unstimulated 45Ca uptake in 1 BR fibroblasts was 4-5 times higher than in DU 145 cancer cells. Depolarization with high extracellular K caused a 2-3-fold increase in 45Ca influx in 1 BR but only 25-55% increase in DU 145 cells. Verapamil caused a significant inhibition of cell growth with an IC50 value of 55 microM. Verapamil paradoxically increased 45Ca uptake in both unstimulated and K-stimulated DU 145 cells. Whereas unstimulated 45Ca uptake could be blocked by very low concentrations of lathanum (10 microM), much higher concentrations (1-10 mM) were required to completely block uptake in K-depolarized cells. Both trifluoperazine and tamoxifen also inhibited cell proliferation with an IC50 concentration of approximately 5 microM. These drugs, had, however, no effect on 45Ca uptake either in unstimulated or depolarized cells. The results suggest that voltage-gated calcium channels exist in both DU 145 cancer cells and fibroblasts. However, verapamil, in contrast to 1 BR, failed to block these channels in DU 145 cells. The mechanism of antiproliferative action of verapamil may be related to the observed, although paradoxical, increase in cellular calcium. The effect of trifluoperazine and tamoxifen does not involve changes in transmembrane calcium movements but could be mediated by their inhibition of calmodulin-mediated reactions within the cell.
TL;DR: To determine whether prostatic acid phosphatase (PAP) immunoreactivity in prostatic adenocarcinoma is a reliable prognostic factor, the PAP immunohistochemical distribution has been examined in 78 prostatic carcinoma cases.
Abstract: To determine whether prostatic acid phosphatase (PAP) immunoreactivity in prostatic adenocarcinoma is a reliable prognostic factor, the PAP immunohistochemical distribution has been examined in 78 prostatic carcinoma cases. The intensity of PAP immunostaining was graded from 0 to 2, and the scores of the primary and the secondary staining patterns were added to assess the extent of the PAP expression in needle biopsy specimens. As a result, a higher cancer-specific survival rate was observed in patients showing a greater PAP immunostaining (P less than 0.01). Further, a multivariate analysis was made of possible prognostic factors (age, stage, Gleason score, serum PAP, PAP-immunostaining score, and the initial treatment) to estimate the extent of their impact on cancer-specific survival. Results have confirmed that the difference in PAP immunoreactivity is an excellent, independent prognostic factor for prostatic carcinoma.
TL;DR: Development of the metastatic ability in AT2.1 cells is not a single‐step reaction regulated by the level of H‐ras expression alone, but rather a complex process requiring additional events, one of which appears to be an increase in genetic instability and cytogenetic changes following v‐H‐ras transfection.
Abstract: To study the relationship between metastatic ability, mutated H-ras expression, and genetic instability, a cloned, nonmetastatic rat prostatic cancer cell line (AT2.1) was transfected with the v-H-ras oncogene. The parental AT2.1 clone, 4 control transfectants (Neo/Only), and 9 v-H-ras transfectants (Neo/Ras) were characterized with regard to their H-ras content by using Southern, Northern, and Western blot analysis and their biological behavior in vivo. Following s.c. inoculation in syngeneic rats, all transfectants produced tumors. All 4 (Neo/Only) transfectants like the parental untransfected cell were non-metastatic. Six of 9 Neo/Ras transfectants were metastatic to the lungs and lymph nodes, while the other 3 Neo/Ras transfectants were not metastatic. There was no simple dose-response relationship between the level of v-H-ras integration, mRNA or p21 protein expression, and the development of metastatic ability by the Neo/Ras transfectants. Cytogenetic analysis demonstrated that the frequency of additional structural and/or additional numerical chromosomal changes among the Neo/Ras transfectants was significantly higher than that in the Neo/Only transfectants (P less than 0.05). Loss of chromosome 10 was observed in all of the Neo/Ras transfectants, whereas that was observed in only one of the 4 Neo/Only transfectants (P less than 0.05). There were no specific chromosomal changes, however, which were statistically correlated with the development of metastases in the Neo/Ras transfectants. These results demonstrate that development of the metastatic ability in AT2.1 cells is not a single-step reaction regulated by the level of H-ras expression alone, but rather a complex process requiring additional events. One of the additional events appears to be an increase in genetic instability and cytogenetic changes following v-H-ras transfection.
TL;DR: The steroid receptor profile inSeven prostate cancer metastases was compared with the profile in seven primary prostate cancers, and the total androgen receptor content was similar in metastatic and primary disease, with a shift towards a cytosolic predominance in metastases.
Abstract: The steroid receptor profile in seven prostate cancer metastases was compared with the profile in seven primary prostate cancers. The secondaries were all lymph node metastases, obtained during pelvic lymphadenectomy, preceding radical prostatectomy or irradiation. Cytosol androgen receptor content was higher in metastases, whereas the nuclear androgen receptor content was only one-fourth that in primary cancer. Cytosol progesterone as well as estrogen receptor contents were markedly lower in metastases compared with primary cancer. The steroid receptor profile differed very little between primary cancer and normal tissue. Primary prostatic carcinoma is usually obtained at early stages of the disease, whereas metastases represent a dedifferentiated, more aggressive cell population. This may explain the low amounts of progesterone, estrogen, and nuclear androgen receptor levels. The total androgen receptor content was similar in metastatic and primary disease, however, with a shift towards a cytosolic predominance in metastases. Possibly androgen receptors in metastatic disease are "deactivated."
TL;DR: It is concluded that intramuscular PEP monotherapy is associated with low cardiovascular mortality and with an all‐cause and prostatic cancer mortality equal to orchiectomy.
Abstract: Four hundred and seventy-seven prospectively randomized patients with prostatic carcinoma were treated with a combination of intramuscular polyestradiol phosphate (PEP) and oral ethinyl estradiol, with intramuscular PEP alone, or with orchiectomy. The cardiovascular and all-cause mortality of the two estrogen therapy modalities and orchiectomy were compared with those of the Finnish male population in general. The age-standardized rate ratios (approximately relative risk) for cardiovascular mortality and for all-cause mortality were 1.51 and 2.31 in the combination estrogen therapy group, 0.17 and 1.50 in the PEP monotherapy group, and 0.78 and 1.78 in the orchiectomy group, respectively. Further mortality rates by cause for all three treatment groups were standardized for age using the age-specific person-years at risk as standard. Age-standardized mortality from cardiovascular diseases was very low in the PEP group, as compared to other treatment modalities, and the mortality rates for prostatic cancer were about equal in all three treatment groups. It is concluded that intramuscular PEP monotherapy is associated with low cardiovascular mortality and with an all-cause and prostatic cancer mortality equal to orchiectomy.
TL;DR: There was a well‐balanced distribution of patients regarding the important pretreatment characteristics in different morphological types of prostatic hypertrophy regarding prostate volume, postvoiding residual volume, mean peak flow rate, and mean symptom score on the FDA scale.
Abstract: During a 7-month period, 79 patients with benign prostatic hyperplasia (BPH) were treated with 915 MHz transurethral hyperthermia (TUHT). All patients had obstructive and irritative signs and symptoms which warranted surgical treatment considerations. Of the 79 patients treated, 31 had follow-ups of 12 months or longer and seven additional patients experienced treatment failure requiring surgical management. These 38 patients were studied to evaluate the relationship of treatment response to the pretreatment prostatic morphology assessed during cystoscopy. There was a well-balanced distribution of patients regarding the important pretreatment characteristics in different morphological types of prostatic hypertrophy. These important characteristics included: prostate volume, postvoiding residual volume, mean peak flow rate, and mean symptom score on the FDA scale. The study patients were scheduled to receive five 60-min TUHT sessions with temperature controlled on the urethral surface at 45.5 degrees C. The treatment were well tolerated and administered on an outpatient basis without sedation or anesthesia. There was a significant difference in the incidence of major improvement in patients with lateral lobe hyperplasia and those with median lobe enlargement, 73 vs. 30%, P = 0.018. From this study, it appears that BPH patients who are found at cystoscopy to have a predominance of median lobe hypertrophy should, perhaps, be selected for treatment other than TUHT. A Phase I study utilizing a modified transurethral applicator to accommodate the specific problem of patients with median lobe hyperplasia is currently being planned.
TL;DR: The total inhibition of spermatogenesis, as well as atrophic signs in the prostate and seminal vesicles, demonstrated a marked suppression of the pituitary‐gonadal system by these analogs.
Abstract: Rats bearing Dunning R-3327 hormone-dependent prostate tumors were treated with LH-RH antagonist SB-75 in the form of microcapsules for sustained delivery administered every 3 weeks and which released 24, 48, 72 micrograms/day respectively. The effects were compared with those of microcapsules of the agonist D-Trp-6-LH-RH releasing 25 micrograms/day. Both types of LH-RH analogs significantly inhibited tumor growth over a period of treatment lasting 8 weeks. The effect of SB-75 was dose-dependent. The total inhibition of spermatogenesis, as well as atrophic signs in the prostate and seminal vesicles, demonstrated a marked suppression of the pituitary-gonadal system by these analogs. The histological signs of tumor regression were analyzed. The vascular content of tumors did not change after the treatments, but an increased amount of connective tissue was found in the treated tumors, especially after administration of SB-75. Both the agonist and the antagonist caused a moderate decrease of the number of mitotic cells and a marked increase of apoptosis in the tumors. The apoptotic index, i.e. the percentage of tumorous glands showing signs of apoptosis, reached 40-50% in treated groups, compared to only 15% in controls. An apoptotic index of 60% was noted in a separate group of rats treated with 200 micrograms SB-75/animal/day for 3 days. The signs of enhanced apoptosis disappeared 1 week after the short-term treatment. The induction of apoptosis by LH-RH analogs seemed to be of greater importance in tumor growth inhibition than their antimitotic effect. These results extend our previous observations on the efficacy of LH-RH antagonists in inhibition of various cancers. This histopathologic evaluation clearly supports our contention that modern antagonists of LH-RH, free of edematogenic effects, inhibit the growth of Dunning prostate tumors. Because of the immediate inhibitory effects, the use of LH-RH antagonists might lead to an improvement in the clinical response in patients with prostate cancer.
TL;DR: It is shown here that DU 145 prostate cancer cells have a decreased amount of EGFR in confluent cultures when compared to levels seen in subconfluent cultures, reminiscent of the situation existing in some tumors whereby EGFR expression is higher in cells at the invading margins of the tumor.
Abstract: Androgen-independent prostate cancer cells may rely on an autocrine loop for growth stimulation, and have been shown to express both the epidermal growth factor receptor (EGFR) and its stimulatory ligands. We have shown here that DU 145 prostate cancer cells have a decreased amount of EGFR in confluent cultures when compared to levels seen in subconfluent cultures. This down-regulation of EGFR numbers is not due to cell proliferation or nutrient depletion, but can be correlated only with whether cell-cell contact exists throughout the culture. This is reminiscent of the situation existing in some tumors whereby EGFR expression is higher in cells at the invading margins of the tumor.
TL;DR: Participation of growth factors and intracellular cAMP in direct antiproliferative action of interferon α (IFN‐α) was investigated in PC‐3 human prostate carcinoma cell line, and it was found that neither growth factors nor a growth inhibitor participated in the action of IFN‐ α.
Abstract: Participation of growth factors and intracellular cAMP in direct antiproliferative action of interferon alpha (IFN-alpha) was investigated in PC-3 human prostate carcinoma cell line. IFN-alpha inhibited proliferation of PC-3 cells in a dose-dependent manner in vitro, and the effect was reversible. Fibroblast growth factor, epidermal growth factor and platelet-derived growth factor, when added to the culture medium, showed no effect on growth of PC-3 cells in presence or absence of IFN-alpha. Transforming growth factor beta (TGF-beta) significantly inhibited PC-3 cell growth, and the effect was additived to that of IFN-alpha. TGF-beta content in conditioned medium of PC-3 cells was not affected by treatment with IFN-alpha. On the other hand, IFN-alpha increased intracellular cAMP concentration about 20-fold. Dibutyryl cAMP and reagents which elevated intracellular cAMP level also inhibited PC-3 cell growth. These indicated that direct antiproliferative effect of IFN-alpha on PC-3 cells was at least partly mediated by cAMP, and that neither growth factors nor a growth inhibitor participated in the action of IFN-alpha.