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1.
The precursors tyrosine and tryptophan as well as the synthesizing and deaminating enzymes of catecholamines have been identified in methylcholanthrene-induced prostatic carcinoma of rats. Tyrosine hydroxylase, monoamine oxidase, catechol O-methyltransferase, dopamine, 5-hydroxytryptamine, and 5-hydroxyindoleacetic acid seemed to be neoplastic in origin, since electron microscopic studies failed to reveal the presence of any neuronal elements in this squamous epithelial cell carcinoma. Castration of rats significantly reduced the activity of tyrosine hydroxylase and the levels of tyrosine, dopamine, tryptophan, 5-hydroxytryptamine, and 5-hydroxyindoleacetic acid in prostate tumors. The changes appeared to be androgen specific since reintroduction of testosterone restored several of these biochemical parameters virtually to control limits. Chemical sympathectomy induced by 6-hydroxydopamine failed to alter monoamine metabolism; however, the prostatic tumor grown in 6-hydroxydopamine-treated rats showed significantly (32%) less necrosis than those grown in normal animals.  相似文献   

2.
Human papillomavirus deoxyribonucleic acid was detected in prostate tissue from patients with benign prostatic hyperplasia or prostatic carcinoma. Radiolabelled genomic probes, specific for the sexually transmitted human papillomavirus types 16 and 18, were used to detect viral genomic sequences in prostate DNA samples analyzed by the Southern blot technique. Viral sequences were identified in DNA from 7 of 16 prostate samples including both hyperplastic and carcinoma tissues and including tissues obtained by transurethral resection or suprapubic prostatectomy. These data indicate that the prostate gland can be infected with human papillomavirus and imply that the prostate may act as a reservoir for the sexual transmission of papillomavirus via seminal fluid. The detection of both episomal and integrated viral DNA sequences in prostate tissue may have important implications for the etiology of prostate disease.  相似文献   

3.
Polyamines and prostatic cancer   总被引:7,自引:0,他引:7  
The importance of polyamines in prostatic growth and differentiation has prompted studies to evaluate the clinical relevance of the ornithine decarboxylase/polyamine system in prostatic cancer. These studies show that differences in biological behaviour of prostatic (cancer) cells are associated with changes in polyamine levels and/or the activity of their metabolic enzymes. Faulty antizyme regulation of polyamine homoeostasis may play an important role in the growth and progression of prostatic carcinoma. Treatment of human prostate carcinoma cells with inhibitors of polyamine metabolic enzymes or polyamine analogues induces cell growth arrest or (apoptotic) cell death. Our recent in vitro studies using conformationally restricted polyamine analogues show that these compounds inhibit cell growth, probably by inducing antizyme-mediated degradation of ornithine decarboxylase. Sensitivity of human prostate cancer cells for these compounds was increased in the absence of androgens. These results suggest that these analogues might have chemotherapeutic potential in case prostatic cancer has become androgen-independent. Pilot data in an in vivo model show that these analogues have effects on tumour cell proliferation, vascularity, blood perfusion and tissue hypoxia. Overall, these studies show that polyamines may serve as important biomarkers of prostatic malignancy and provide a promising target for chemotherapy of prostatic cancer.  相似文献   

4.
Four methods available for the diagnosis of carcinoma of the prostate-digital rectal evaluation, prostatic smear, needle biopsy and open perineal or transurethral biopsy-were studied and correlated.One hundred ten patients with clinical indications of cancer of the prostate were subjected to needle biopsy and open perineal or transurethral biopsy. Seventy of the same patients had prostatic smear examination. Using the open perineal biopsy or the positive transurethral biopsy as the standard, the accuracy of prostatic palpation, prostatic smear and needle biopsy were obtained.A high degree of correlation (74 per cent) was demonstrated between digital rectal evaluation and positive surgical biopsies in both early and late cases. There were 17 false positive clinical diagnoses. The prostatic smear showed an overall correlation of 45 per cent when compared with the results of positive surgical biopsy. The overall accuracy of needle biopsy was 73 per cent. However, in the last 39 cases, including eight in which the carcinomas were of groups A and B (curable), the needle accuracy was 100 per cent. When there is clinical indication of malignant disease of the prostate, needle biopsy of the lesion is warranted and should be done before definitive or palliative treatment is undertaken.  相似文献   

5.
6.
Prostate-specific antigen (PSA) is a tissue-specific glycoprotein identified by Wang in 1979. It is synthesized in the prostate independently of prostatic acid phosphatase (PAP). A total of 199 subjects were divided into four groups: controls aged less than 50 years, controls aged more than 50 years, patients with benign prostatic hyperplasia (BPH) and patients with prostatic carcinoma. PSA cut-off value was set at 10 ng/ml (mean for the BPH group plus 2 SD). With this cut-off value PSA could not be used as an early predictor of prostatic carcinoma. The association of PSA and PAP in prostatic cancer increases the number of patients with positive biological markers.  相似文献   

7.
About 28 per cent of men between the ages of 71 and 75 have cancer of the prostate. Many of them do not die of the disease, but with the life span ever increasing, this problem is becoming more important.In the early stages the condition is asymptomatic; when the symptoms of urinary obstruction arise, the cancer is usually too advanced for cure. Cure depends on early diagnosis and, therefore, on routine rectal examination. The solitary hard nodule of early prostatic cancer becomes a stony hard fixed prostate as the condition progresses. X-ray and acid phosphatase studies are of help only after the cancer has metastasized. As many as 50 per cent of patients with rectally palpable early carcinoma of the prostate can be cured by radical perineal prostatectomy. Often, simple enucleation or transurethral resection is sufficient to effect cure in the case of occult carcinoma. However, some observers believe that when cancer is detected by microscopic examination of a prostate that has been removed, a radical operation should be done as soon after the initial operation as feasible. Early orchidectomy and estrogen therapy are of considerable help in slowing the process of advanced prostatic cancer and may postpone the need of transurethral resection to relieve obstruction. When these measures fail, bilateral adrenalectomy, cortisone therapy, pituitary irradiation, and pituitary extirpation have been employed, with moderate success, in an effort to diminish the androgen level.  相似文献   

8.
About 28 per cent of men between the ages of 71 and 75 have cancer of the prostate. Many of them do not die of the disease, but with the life span ever increasing, this problem is becoming more important. In the early stages the condition is asymptomatic; when the symptoms of urinary obstruction arise, the cancer is usually too advanced for cure. Cure depends on early diagnosis and, therefore, on routine rectal examination. The solitary hard nodule of early prostatic cancer becomes a stony hard fixed prostate as the condition progresses. X-ray and acid phosphatase studies are of help only after the cancer has metastasized. As many as 50 per cent of patients with rectally palpable early carcinoma of the prostate can be cured by radical perineal prostatectomy. Often, simple enucleation or transurethral resection is sufficient to effect cure in the case of occult carcinoma. However, some observers believe that when cancer is detected by microscopic examination of a prostate that has been removed, a radical operation should be done as soon after the initial operation as feasible. Early orchidectomy and estrogen therapy are of considerable help in slowing the process of advanced prostatic cancer and may postpone the need of transurethral resection to relieve obstruction. When these measures fail, bilateral adrenalectomy, cortisone therapy, pituitary irradiation, and pituitary extirpation have been employed, with moderate success, in an effort to diminish the androgen level.  相似文献   

9.
Biochemical and cytochemical inhibition experiments of rat prostatic acid phosphatase were performed using enzymes separated on isoelectric focusing (IEF) gels, and thin sections of the rat ventral prostate. Various inhibitors, including L (+) tartrate, mercuric ions and sodium fluoride were applied to electrofocused enzymes which were subsequently stained for acid phosphatase activity. Enzymes focused on IEF gels at pH 7.9 and 8.1, respectively, were inhibited with 1.8 x 10-3 M tartrate, while the enzyme activities with isoelectric points (pl) of 5.6 and 7.15, respectively, were only slightly inhibited by this compound. Using 10-3M mercuric ions, enzymes with pl of 5.6 and 7.15 were inhibited while the enzymes with pl of 7.9 and 8.1 were still active. The biochemical procedures were adapted to chopper sections of perfused-fixed ventral prostate of the rat. Preincubation of the sections with 2.4 x 10-3M mercuric chloride blocked the secretory enzyme and most of the lysosomal enzyme and resulted in an artificial staining of the Golgi apparatus and other cytoplasmic organelles. Nuclear precipitates however were prevented. L (+) tartrate could not be used at the ultrastructural level since it developed false positive results by the formation of lead tartrate. The results indicate that no selective inhibition of either secretory or lysosomal acid phosphatase can be achieved at the ultrastructural level using metal salts or tartrate, respectively.  相似文献   

10.
Recently, the scanning force microscope (SFM) has been widely used for direct monitoring of specific interactions between biologically active molecules. Such studies have employed the SFM liquid-cell setup, which allows measurements to be made in the native environment with force resolution down to a tenth of a picoNewton. In this study, the ligand–receptor strength of monoclonal anti-human prostatic acid phosphatase and prostatic acid phosphatase, representing an antigen–antibody system with a single type of interaction, was determined. Then, the interaction force occurring between concanavalin A and the carbohydrate component of the glycoproteins arylsulfatase A and carboxypeptidase Y was measured. High mannose-type glycans were sought on the human prostate carcinoma cell surface. Application of an analysis based on the Poisson distribution of the number of bonds formed in all these measured systems allowed the strength of the molecular interaction to be calculated. The values of the force acting between two single molecules were 530±25, 790±32, and 940±39 pN between prostatic acid phosphatase and monoclonal anti-human prostatic acid phosphatase, between concanavalin A and arylsulfatase A, and between concanavalin A and carboxypeptidase Y, respectively. The value calculated from data collected for the force between concanavalin A and mannose-containing ligands present on the surface of human prostate carcinoma cells was smaller, 116±17 pN. The different values of the binding force between concanavalin A and mannose-containing ligands were attributed to the structural changes of the carbohydrate components.  相似文献   

11.
We have isolated four cDNAs encoding the entire preproprotein of prostate specific antigen from human prostatic cDNA libraries. Comparison of the coding regions of prostate specific antigen with human pancreatic kallikrein (1-3) and human glandular kallikrein (4) showed 73%-84% nucleotide and 61-77% amino acid homologies, respectively, between these enzymes. Also the 3' noncoding regions of these genes were conserved. The close resemblance of prostate specific antigen, a marker for prostatic cancer, to glandular kallikrein suggests related immunogenic properties for them.  相似文献   

12.
The levels of polyamines and their synthesizing enzymes in squamous cell carcinoma of prostate implanted in intact as well as castrated male rats were determined after certain hormonal manipulations. The tumour was found to grow with an identical rate in non-castrated and castrated rats. Polyamine content and activities of polyamine synthesizing enzymes in the tumour were found to be much lower compared to their values in ventral prostate. Moreover, the levels of these parameters were comparable in tumours whether implanted in non-castrated or gonadectomized animals. The sequential analyses of putrescine and spermidine and activities of L-ornithine decarboxylase and S-adenosyl-L-methionine decarboxylase of tumours at different time intervals showed a significant reduction in their levels at 30 days compared to 10 days post implantation in non-castrated as well as castrated rats. Daily intramuscular administration of tumour-bearing intact or castrated animals with testosterone (50 micrograms/g), beta-estradiol (2 micrograms/g) or cyproterone (12.5 micrograms/g) for 10 days did not influence polyamine metabolism in tumour tissue. However, either beta-estradiol and cyproterone treatments or castration were found to decrease polyamine synthesis in ventral prostate. At the same time, the testosterone replacement therapy did not allow polyamine levels or activities of polyamine synthesizing enzymes to decline in the ventral prostate of castrated rats. Our results demonstrated that contrary to ventral prostate, the polyamine metabolism in squamous cell carcinoma of prostate is independent of hormonal control. The loss of hormonal sensitivity of polyamine metabolism in the prostatic tumour could be the result of qualitative changes that occurred during transformation.  相似文献   

13.
The objective of the present study was to study whether adipose tissue and prostatic tissue fatty acid composition differentiates between prostate cancer and benign hyperplasia patients. In addition, the present investigation aimed at exploring the extent to which prostatic tissue fatty acid composition differentiates between prostate-confined cancer and extraprostatic disease including possible metastasis. The subjects were 71 male patients from the island of Crete. Half the patients (n=35) had been diagnosed with benign hyperplasia of the prostate, half with prostatic malignancy (n=36). Patients were examined at the outpatient clinic of the urology unit, University Hospital, Medical School, University of Crete. Relative to benign hyperplasia patients, cancer patients had elevated adipose tissue saturated and reduced monounsaturated fatty acid levels. Cancer patients had reduced prostate tissue stearic to oleic acid ratios and stearic acid levels as opposed to hyperplasia patients. The most pronounced difference between cancer patients and hyperplasia patients was a 3-fold elevated prostatic palmitoleic acid in the former group. Relative to benign hyperplasia patients, cancer patients had reduced prostate tissue arachidonic and docosahexaenoic acid levels. Finally, there was a significantly reduced omega-3/omega-6 polyunsaturated fatty acid ratio in the prostate cancer patient as opposed to the benign hyperplasia group. The pronounced elevations in prostatic tissue palmitoleic acid in cancer patients highlight a possible role of this fatty acid in neoplastic processes. The decreased arachidonic acid levels in cancer patients possibly stem from enhanced metabolism of arachidonic acid via lipoxygenase and cyclooxygenase pathways, and the formation of derivatives such as 5-HETE, 15-HETE, 12(S)-HETE and PGE(2).  相似文献   

14.
Androgens regulate the expression of both human prostatic acid phosphatase (PAcP) and prostate-specific antigen (PSA), two major prostate epithelium-specific differentiation antigens. Due to the important role of these two enzymes as prostate epithelium differentiation markers, we investigated their regulation of expression at the mRNA level in LNCaP human prostate carcinoma cells. Interestingly, phenol red, a pH indicator in the culture medium, promoted cell growth. To eliminate this non-specific effect, a phenol red-free, steroid-reduced medium was utilized. When high-density cells were grown in that medium, 5alpha-dihydrotestosterone (DHT) suppressed PAcP but stimulated PSA. However, tumor promoter phorbol ester 12-o-tetradecanoyl phorbol-13-acetate (TPA) functioned as a potent inhibitor of both PAcP and PSA expression. Prolonged treatment with DHT as well as TPA resulted in a similar down-regulation of protein kinase C and cellular PAcP activities. Thus, the levels of PAcP and PSA mRNA are differentially regulated by androgens in LNCaP cells.  相似文献   

15.
We assayed prostatic specific antigen (PSA) and prostatic acid phosphatase (PAP) serum levels in 1305 subjects without malignant prostatic pathology by double antibody RIA I125 to evaluate their specificity. When we set a second upper normal limit of 10 ng/ml for PSA and 2.5 ng/ml for PAP there was a significant increase of specificity. There were 2 and 3.7% false positive results in non-prostatic benign pathologies, 1.8 and 7.9% in non-prostatic malignant, 3.5 and 4.7% in non-complicated benign prostatic hypertrophy (BPH) and 3.3% for both in chronic prostatitis. In patients with complicated BPH and acute prostatitis the results were 64.8 and 24% for PSA and 20 and 16% for PAP. In conclusion, PSA is more specific than PAP in patients without acute inflammatory pathology of the prostate; the high rate of false positive values in the latter excludes its usefulness in these patients as diagnostic tumoral markers.  相似文献   

16.
Although an increased level of the prostate-specific antigen can be an indication for prostate cancer, other reasons often lead to a high rate of false positive results. Therefore, an additional serological screening of autoantibodies in patients’ sera could improve the detection of prostate cancer. We performed protein macroarray screening with sera from 49 prostate cancer patients, 70 patients with benign prostatic hyperplasia and 28 healthy controls and compared the autoimmune response in those groups. We were able to distinguish prostate cancer patients from normal controls with an accuracy of 83.2%, patients with benign prostatic hyperplasia from normal controls with an accuracy of 86.0% and prostate cancer patients from patients with benign prostatic hyperplasia with an accuracy of 70.3%. Combining seroreactivity pattern with a PSA level of higher than 4.0 ng/ml this classification could be improved to an accuracy of 84.1%. For selected proteins we were able to confirm the differential expression by using luminex on 84 samples. We provide a minimally invasive serological method to reduce false positive results in detection of prostate cancer and according to PSA screening to distinguish men with prostate cancer from men with benign prostatic hyperplasia.  相似文献   

17.
The factors that affect the progression of prostatic carcinoma are poorly understood, but it is known that carbohydrate antigens on the tumour cell surface play a role in the transforming and metastatic processes. The present report aimed to perform a comparative, lectin-histochemical study of benign and carcinomatous prostates, using a battery of lectins, in combination with monoclonal antibodies against Lewis antigens, and a semi quantitative study, to investigate the changes in glycosylation patterns that occur in prostatic carcinoma. Blocks from 27 necropsy cases of prostatic carcinoma were sectioned and stained with H+E, fifteen biotinylated lectins chosen to probe for a wide range of oligosaccharide sequences within several categories of glycoprotein glycans, using a lectin-biotin avidin-peroxidase method, and monoclonal antibodies against Lewisa, sialyl Lewisa and sialyl Lewisx antigens. The glycophenotype of prostatic carcinoma differed from that of the noncancerous prostate in revealing more intense staining with the following lectins (AAA, UEA-1, DBA, WFA, VVA, HPA, BSA-1B4, MPA, ECA, AHA, and CTA), while the binding patterns of (GNA and NPA) were almost similar in both prostatic carcinoma and the noncancerous prostate. Lewis antigens are found to be expressed in prostatic carcinomas but not in the noncancerous prostate. The observations of this study suggest that the gylcophenotype of transformed prostatic cells was modified. It showed a moderate increase in, and changing patterns of, fucosylation and galactosylation, increased branching of side chains and sharp rise in 2 deoxy, 2 acetamido galactosylation and masking process by sialylation, especially by α2-3 and α2-6 linkages. All these changes in the glycosylation pattern of the transformed prostatic cells were observed on O-glycans, no changes were observed on N-glycans.  相似文献   

18.
李文辉  袁建林  张伟  张楠  金雷 《生物磁学》2009,(9):1703-1706
目的:研究Cox-2、P504s、CK34βE12和P63在前列腺腺癌组织中的表达及其临床病理学意义。方法:用免疫组织化学法检测134例正常前列腺、良性前列腺增生和前列腺腺癌石蜡包埋组织中Cox-2、P504s、CK34βE12和P63的表达。结果:正常前列腺组织或良性前列腺增生组织未见或偶见P504s弱表达,但CK34βE12和P63均表达良好;前列腺腺癌组织中P504s表达良好,但CK34βE12和P63均表达消失,P504s表达阳性率为91.07%;与正常前列腺组和良性前列腺增生组相比,前列腺癌组的P504s阳性表达率存在显著性差异(p=0.001)。COX-2在正常的前列腺组织几乎不表达,而良性前列腺增生组织及前列腺腺癌组织均可见阳性表达,阳性率分别为4.76%和80.36%;COX.2阳性表达率在正常前列腺组或良性前列腺增生组和前列腺腺癌组间有显著性差异(p=0.0027)。COX-2与P504s表达存在相关性(r=0.377,P=0.039);COX-2的表达与年龄、临床分期、分化程度、有无远处转移等临床病理特征间无明显相关关系。结论:联合P504s、P63、CK3413E12和COX-2免疫组化检测可提高前列腺腺癌病理诊断的准确率。  相似文献   

19.
Human acid phosphatases from various sources were purified by a new rapid procedure including chromatofocusing and gel permeation chromatography on an FPLC system. Isoenzymes 2a and 4 (Mr 105,000 and 76,000, respectively) are the prevalent acid phosphatases in prostate, leukocytes and bone marrow. Additional forms are proteolytic products formed during isolation procedure. The source of elevated acid phosphatase in blood serum in metastasizing prostatic carcinoma can be either prostate itself, the tumour or, more likely, bone marrow cells destroyed during the invasion by the tumour cells. Distribution of isoenzymes is not organ specific. It was found using an antiserum against isoenzyme 4 that immunoreactivity is confined to the specific secretory granules both of prostatic epithelium and leukocytes.  相似文献   

20.
目的探讨血管内皮细胞生长因子-C(VEGF-C)与血管内皮细胞生长因子受体VEGFR-3(Flt4),在前列腺癌中的表达以及结核菌L型感染率及临床意义。方法应用免疫组化和原位杂交和抗酸染色等方法检测65例前列腺癌(carcinoma of prostate,PCa)和30例良性前列腺增生(benign prostatic hyperplasia,BPH)中的VEGF-C、Fit4蛋白及mRNA的表达,以及结核菌L型的检出率。并对前列腺肿瘤主要临床资料和病理分级参数进行比较,用χ2检验进行统计学处理。结果VEGF-C、Flt4蛋白及mRNA阳性表达率和结核菌L型检出率,前列腺癌明显高于前列腺增生(P0.001~0.05)。VEGF-C、Flt4蛋白及mRNA阳性表达率和结核菌L型检出率与前列腺癌的临床分期、病理分级有明显差异(P0.05)。淋巴结转移组中VEGF-C、Flt4蛋白及mRNA的阳性表达率明显高于非转移组(P0.01)。结核菌L型检出率淋巴结转移组明显高于非转移组(P0.05)。结论VEGF-C、Flt4的蛋白及mRNA在前列腺肿瘤中不同程度异常表达以及结核菌L型检出率与肿瘤的临床分期、病理分级和转移呈正相关,提示这2种基因均可作为判断前列腺癌生物学行为及患者预后参考指标;结核菌L型感染可能有协同致瘤作用,与前列腺癌的发生发展可能有一定关系。因此研究VEGF-C、Flt4的阳性表达和结核菌L型感染与前列腺癌的关系,具有重要的临床应用价值。  相似文献   

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