Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0376358 (prostate cancer)
 59,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The relationship between platelet surface negative charge and hyperfunction was examined by determining electrophoretic mobility (EPM), aggregability, and sialic acid of platelets in prostatic cancer, prostatic cancer with estrogen, prostatic cancer with estrogen and aspirin, prostatic hypertrophy, and healthy aged males. Estrogen treated prostatic cancer patients had significantly higher platelet EPM. A good linear correlation was found between sialic acid and EPM (r = 0.97, p less than 0.001). EPM was negatively correlated with primary aggregations by adrenaline and ADP but not with secondary or maximum aggregations, suggesting increased surface negative charge may inhibit primary aggregation. Estrogen and platelet population changes influenced surface negative charge. Neuraminidase removal of platelet surface sialic acid resulted in dose-dependent decreases of EPM which paralleled decreases in sialic acid. Aspirin treated patients and platelets incubated with aspirin in vitro both showed increased platelet EPM. These results suggest that platelet surface negative charge may directly affect platelet function.
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PMID:Role of surface negative charge in platelet function related to the hyperreactive state in estrogen-treated prostatic carcinoma. 618 Apr 96

In this preliminary study, we have determined the receptors in normal human prostatic tissue or from patients with benign prostatic hypertrophy and patients with prostatic cancer. A single point assay using a dextran-coated-charcoal treatment of cytosol is utilized. This method permits the elimination of endogenous steroids and is also useful when specimens are too small to provide the larger number of aliquots necessary for multiple steroid receptor analyses. The results are discussed in the light of several problems inherent to this assay. We conclude that adenoma-tissue contains more receptors than neoplasic tissues for the progesterones receptors but that there is no significant difference for the estrogen-receptor and the androgen-receptors. For all the adenoma tissues and some neoplasic tissues the level of the estrogen-receptors is always lower than the one for androgen-receptor which itself is lower than the one for progesterone-receptors. We think that the expression of the results as a ratio of two levels of steroid-receptors gives a better evaluation of the receptors. The ratios Progesterone-receptor Estrogen-receptor and Androgen-receptor/Estrogen-receptor are always greater than 1.5, except for some neoplasic tissues and we think that, as in breast tumors, there are perhaps two kinds of neoplastic tissues, one hormone-dependent, the other not.
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PMID:[Comparative study on the concentrations of steroid receptors in adenomatous and cancerous prostatic tissue]. 618 95

The goals of hormonal therapy for prostatic cancer are to decrease circulating plasma testosterone to castration levels; prevent a rise in or reduce circulating prolactin; and block residual androgen at the cell level. Orchiectomy is very effective but does not prevent residual adrenal androgens from being converted to dihydrotestosterone (DHT); also, it has no effect on plasma prolactin. Estrogen has no known effect on androgen-receptor concentration or DHT binding to receptor and raises plasma prolactin. It also has significant side effects. Megestrol acetate, the only antiandrogen currently available for use in the United States, has been shown to block androgen from all sources. It produces a transient reduction in plasma testosterone to levels somewhat higher than those in castrated men, and it has no effect on plasma prolactin. When used in a dose of 120 mg/day in combination with 0.5 to 1.5 mg of estradiol per day, it acts synergistically to suppress pituitary gonadotropins and maintain plasma testosterone at castration levels for periods of up to 1 year. Newer therapies being studied include flutamide, a nonsteroidal antiandrogen, and luteinizing hormone-releasing hormone (LHRH). Data on these agents are limited and comparisons with standard therapies are needed.
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PMID:Comparison of various hormonal therapies for prostatic carcinoma. 619 46

Lack of initial response or relapse to hormones in advanced prostatic cancer may be due to an adverse effect of estrogen on host immune function. This study investigated the effect of diethylstilbestrol diphosphate (DES-P) on the normal mixed lymphocyte reaction (MLR) and on the MLR in prostatic cancer patients before and during treatment with DES-P. These data showed that the normal MLR was suppressed by high concentrations of estrogen in vitro, but physiologic levels of DES-P were not suppressive. Therapeutic doses of DES-P did not suppress the spontaneous MLR of prostatic cancer patients compared with previous treatment. Estrogens did not significantly impair the immunologic responsiveness of normal individuals or prostatic cancer patients.
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PMID:Effect of estrogen on the mixed lymphocyte reaction in normal individuals and prostatic cancer patients. 621 Sep 1

Juvenile nasopharyngeal angiofibromas (JNA) are rare. They have been frequently treated with estrogens, either solely or as an adjuvant therapy prior to surgery or irradiation. Clinical trials have proveded no evidence to explain the objective respose to estrogens observed in some tumors. Since the mechanism of steroid hormone action is mediated via specific receptors, we analyzed 8 JNA for tumor cytosol estrogen receptors. None were positive for estrogen receptors. Additionally, all were also negative for progesterone receptors. Nasopharyngeal angiofibromas occur predominantly in adolescent boys at a time when there is a gradual change in androgen availability. Therefore, three latter angiofibromas were also analyzed for the presence of cytosol androgen receptor. Specific testosterone and dihydrotestosterone binding components in the tumor cytosol were detected. This observation raises for the first time the possibility that JNA may be an androgen-dependent tumor. Estrogen may act as an antiandrogen on these tumors, an action similar to that on prostate cancer.
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PMID:Hormonal receptor determination in juvenile nasopharyngeal angiofibromas. 624 85

To study the participation of cAMP in the action of gonadotropin on testicular steroidogenesis in the human testis in vivo, we have measured the concentrations of cAMP, testosterone, 5 alpha-dihydrotestosterone, estrone, 17 beta-estradiol, and hCG in the spermatic venous blood of the patients with prostatic cancer after hCG injections into the testis. Five minutes after hCG administration, spermatic cAMP increased to 5 times the pretreated level, and after 30 min, it increased to 20 times the pretreated level. Testosterone increased gradually after hCG injection, and the 2-fold increase was demonstrated at 50 min. Although the pattern of the changes in spermatic 5 alpha-dihydrotestosterone was similar to that of testosterone, a statistically significant increase was not observed after hCG administration. Estrogen production was also stimulated by hCG. These results are consistent with the view that cAMP may participate in the action of hCG upon steroidogenesis in the testis of human beings in vivo, as has previously been observed with rat and human testes in vitro.
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PMID:Stimulation of adenosine 3',5'-monophosphate and sex steroids in the spermatic venous blood after human chorionic gonadotropin injection into human testes. 625 90

We compared the efficacy and safety of the gonadotropin-releasing hormone analogue, leuprolide (1 mg subcutaneously daily), with diethylstilbestrol (DES, 3 mg by mouth daily) in patients with prostate cancer and distant metastases (Stage D2) who had not previously received systemic treatment. Initial therapy (leuprolide or DES) was continued for as long as an objective response was noted; cross-over to the alternative arm occurred at the time of disease progression or intolerable adverse reactions. Ninety-eight patients were randomly assigned to leuprolide, and 101 to DES. Suppression of testosterone and dihydrotestosterone and decreases in acid phosphatase were comparable in the two groups. Patients receiving DES experienced more frequent painful gynecomastia (P less than 0.00001), nausea and vomiting (P = 0.02), edema (P = 0.008), and thromboembolism (P = 0.065) than those receiving leuprolide. The leuprolide group reported more "hot flashes" (P = 0.00001). Overall, 86 per cent of the leuprolide group had an objective response (complete response, 1 per cent; partial response, 37 per cent; stable disease, 48 per cent), as compared with 85 per cent of the DES group (complete, 2 per cent; partial, 44 per cent; stable, 39 per cent). Actual survival rates at one year were 87 per cent for the leuprolide group and 78 per cent for the DES group (P = 0.17). We conclude that leuprolide offers an important alternative treatment that is therapeutically equivalent to and causes fewer side effects than DES for the initial systemic management of metastatic prostate cancer.
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PMID:Leuprolide versus diethylstilbestrol for metastatic prostate cancer. 643

Analysis of the different rate of prostatic cancer in Israel among Jews from various countries of origin reveals some very interesting and marked varieties in incidence, which are studied more closely now. Aggressive, combined treatment for the invasive cases of prostatic cancer has been used since 1975. This was based on orchiectomy, DES, and chemotherapy for the stage D2 disease, and on radiotherapy and hormonal therapy for the stage C, and possibly also the stage D1 disease. Results so far have been very encouraging indeed, and with considerably better results than obtained with the individual, more conventional forms of therapy. Five-year survival in the stage D2 disease has been 63.5%, and 87.6% in the stage C (+D1?) disease. It appears that this approach is more justified, certainly in the advanced stages of this disease.
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PMID:Carcinoma of the prostate in Israel: some epidemiological and therapeutic considerations. 673 72

Patients with bulky prostate cancer have usually been treated by palliative measures because the likelihood of tumor control with definitive irradiation has been low and the development of distant metastases high. The addition of estrogen to irradiation has not been shown to be of value. However, we believe the method of estrogen administration may have been the cause for the apparent lack of benefit. Estrogen had been started either concurrent with irradiation or had been used for palliation and was given for long and unscheduled time periods prior to irradiation. We have used estrogen for two months prior to and concurrent with irradiation. We postulated that in those patients with estrogen responsive cancer, the reduced tumor burden prior to irradiation could enhance tumor control and survival. Between 1975 and 1980, 25 patients with bulky prostate cancer received sequential estrogen and irradiation, 12 patients irradiation alone and six patients irradiation after having become refractory to long-term estrogen use. One patient was lost to follow-up. Eighteen of 25 (72%) treated by sequential estrogen and irradiation, 14/17 (82%) with estrogen responsive cancer and 4/8 (50%) with estrogen resistant cancer had a complete tumor response. Six of 11 (55%) patients treated by irradiation alone and 2/6 (33%) treated by irradiation for estrogen refractory cancer had a complete tumor response. Disease-free survival was observed in 13/25 (52%) treated by sequential estrogen and irradiation, and 8/17 patients (47%) with irradiation. It is also possible the improved survival in the estrogen responsive group was a direct result of improved local control. Persistent local disease can act as a source for distant metastases. Distant metastases was observed in 15% of patients when the primary tumor was controlled and 30% when there was persistent or recurrent local disease. Also, progressive local disease can be an important cause of death. This was most evident in our patients with estrogen refractory cancer. Almost all patients in this group had progressive local disease that caused serious urinary bleeding and urinary infection that were considered the major cause of death. Our results suggest bulky prostate cancer should be aggressively treated when first diagnosed. The value of adjunct estrogen is unproven. Our results with the use of estrogen prior to and concurrent with irradiation is encouraging. Estrogen may shrink the cancer and allow for a more favorable geometry for external irradiation. Tumor control and survival may be thereby improved.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Improved control of bulky prostate carcinoma with sequential estrogen and radiation therapy. 674 58

Two parallel prospective randomized studies have been undertaken by the EORTC Urological Group in previously untreated patients with prostatic cancer in order to compare low dose Stilboestrol versus Cyproterone acetate versus Medroxyprogesterone acetate in the first trial, and Stilboestrol versus Estracyt in the second trial. Although the follow up is still short, no superiority of the other drugs over Stilboestrol had appeared so far with regard to either objective response or significant side effects apart from gynaecomastia. In the third trial, patients with advanced disease no longer responsive to hormonal treatment were randomized to either Adriamycin or Procarbazine. Toxicity and early death were particularly frequent in Procarbazine treated patients, whereas most patients progressed in both treatment groups.
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PMID:EORTC protocols in prostatic cancer. An interim report. 693 20


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