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)

Evidence of significant suppression of tumour-associated immunity in patients with prostatic cancer by human seminal plasma (HuSPl) has been observed. Collation of the immunosuppressive property of HuSPl in this and previous studies, together with recent studies demonstrating experimental induction of prostatic cancer by spermatozoa and the relationship of prostatic cancer to sexual activity are suggestive of an etiologic role for SPl in prostatic cancer.
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PMID:Effect of human seminal plasma on tumour-associated immunity in prostatic cancer. A preliminary report. 51 May 6

Major developments in birth control vaccines are on the horizon. The human chorionic gonadotropin (hCG) vaccine has entered phase II clinical trials after successful completion of phase I studies at 5 centers in India and 4 centers abroad. It is the most advanced vaccine of its type in the world. The trials are being conducted on women of proven fertility who are sexually active. The available results indicate the efficiency of the vaccine to prevent pregnancy in women at or above titres of 50 ng/ml. A vaccine inducing antibodies against gonadotropin releasing hormone (GnRH) has been approved in India for trials in postpartum women, to determine whether immunization can help prolong lactational amenorrhea. The GnRH vaccine is also in clinical trial in prostate cancer patients at 2 centers in India and in Austria and the Dominican Republic. The follicle stimulating hormone (FSH) vaccine is about to enter phase I clinical trial after completing experimental and toxicological studies. A vaccine against FSH has been developed for human males employing ovine FSH (oFSH) as an immunogen. oFSH adsorbed on alum induces antibodies reactive with human FSH in bonnet monkeys. Immunization leads to oligospermia with resultant impairment of fertilization potential. No reduction in testosterone levels has been reported. Research is in progress to identify antigens on spermatozoa, which could serve as vaccine candidates. PH-20, a protein located on the inner acrosomal membrane of capacitated sperms, has been reported to have 100% contraceptive efficacy in both sexes of guinea pigs in active immunization studies. cDNA probes of PH-20 cross-react with genomic DNAs of mouse, rat, hamster, and human. The sperm antigen, lactate dehydrogenase C4 (LDH-C4), is a glycolytic enzyme. Active immunization with LDH-C4 suppressed fertility in mice, rabbits, and baboons. SP-10, which is a testis-specific human sperm protein, is also a promising candidate.
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PMID:Vaccines for control of fertility. 129 38

Recent approaches to inhibiting testicular function for the purposes of male contraception, treatment of precocious puberty, and palliation of prostatic disease (prostatic carcinoma and benign prostatic hypertrophy) are addressed. By refined approaches inhibition of testicular function can be achieved at points of the reproductive axis, including the hypothalamus, pituitary testis, and peripheral sites of androgen action. Azoospermia and severe oligozoo/azoospermia can be achieved with combined gonadotropin releasing hormone (GnRH) antagonists and replacement doses of testosterone. In recent developments with reversible hormonal agents, the use of gonadotropin inhibitors for male contraception was based on observations that hypophysectomized and hypogonadotropic men (deficient in luteinizing hormones [LH] and follicle stimulating hormone [FSH] are aznoospermic. Long term suppression of LH and FSH with steroids and GnRH analogues has proven to be reversible with discontinuation of medication suggesting that inhibitors of LH and FSH secretion would prove to be effective and reversible male contraceptive agents. Steroid hormones suppress gonadotropin output and secondarily suppress testicular function including the production of spermatozoa. The androgen testosterone enanthate in doses of 200 mg every week suppressed LH and FSH concentrations to 50% of pretreatment baseline. True precocious puberty can be managed more effectively by suppression of gonadotropin secretion with GnRH analogues. Metastatic prostate cancer, previously treatable with either castration or estrogens, now responds to suppression of androgen secretion. Benign prostate hyperplasia previously manageable only by surgery can respond favorably to 5 alpha-reductase inhibitors and/or selective alpha-adrenergic blockers in some patients according to recent data.
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PMID:Developments in the control of testicular function. 137 67

The vasa deferentia of men and monkeys were studied and compared with special attention to spermiophagy by epithelial cells in the ampullary region. Specimens were obtained from adult men who were subjected to total vasectomy for early prostatic cancer and from healthy adult Japanese monkeys (Macacus fuscatus). The vasa do not differ greatly in gross and microscopic morphology between man and monkey. The mucosal lining of the vas, except for its ampullary region, is generally smooth with occasional infoldings and consists of a pseudostratified columnar epithelium. The free epithelial surface is covered by dense mat of long microvilli (stereocilia) on which a few spermatozoa reside. In contrast to other regions of the vas, the ampullary lumen has a spindle-shaped dilation and complicated infoldings of the mucosa, the mucosa is wider and much more infolded in man than in monkey. The columnar epithelial cells characteristically contain abundant secretory granules in the cytoplasm and bear short, stubby microvilli in the place of stereocilia. Worthy of special mention in the ampullary region of the vas in both species is that various stages of spermiophagy by the epithelial cells are extensively visualized by SEM. The ampullary region may play a role in the removal of excess spermatozoa in addition to the storage of them.
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PMID:Scanning electron microscopic observations of the vas deferens in man and monkey with special reference to spermiophagy in its ampullary region. 717 Jun 8

The immunosuppressive properties of the hormonal and/or secretory milieu or tumor-elaborated factors (in the case of carcinoma) of the prostate have been hypothesized as contributory to the natural history of prostatic cancer. The effect of normal human seminal plasma (HuSP1) on immunity to tumor-associated antigens in patients with prostatic cancer has been evaluated by leukocyte adherence inhibition, a suggested in vitro correlate of cellular immunity. Significant (p less than 0.01) suppression of immunity to malignant prostate ranging from 16 to 80% of the level of reactivity obtained with unincubated patients' leukocytes was observed in 22 (88%) of 25 patients following preincubation of their leukocytes with HuSP1. Suppression of tumor-associated immunity by HuSP1 provides further evidence to studies by other demonstrating SP1 suppression of a range of immune responses in normal murine and human hosts. In addition to the possible biological implications of the immunosuppressive properties of SP1, e.g., as directed toward preservation of the species, whereby under normal conditions tolerance to spermatozoa in the male tract and in the female tract, following coitus, is maintained, it is hypothesized on the basis of collation of studies demonstrating experimental prostatic cancer from sensitization by spermatozoa and the relationship of prostatic cancer to repression of sexual activity, that SP1 may play a significant role in the natural history of prostatic cancer.
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PMID:Suppression of tumor-associated immunity by human seminal plasma and its possible role in the natural history of prostatic cancer. 738 76

Tumour-associated antigen-induced leukocyte adherence inhibition has been used as an in vitro criterion for evaluating the effect of normal human seminal plasma (HuSePl) on cell-mediated anti-tumour-associated immunity in patients with adenocarcinoma of the prostate. Significant (P < 0.01) suppression from the reactivity obtained with unincubated patients' leukocytes to allogenic extracts of malignant prostatic tissue ranging from 16 to 80% was observed in 22 of 25 patients (88%) following preincubation of their leukocytes with HuSePl. The observed suppression of tumour-associated immunity in the presence of HuSePl provides further evidence for the suppressive activity of SePl on a range of in vitro immune response in normal murine and human hosts. It is suggested that these results, together with those demonstrating experimental prostatic cancer from sensitization by spermatozoa and the relationship of prostatic cancer to repression of sexual activity, provide preliminary evidence of the possible participation of SePl as contributory to the natural history of prostatic cancer.
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PMID:Effect of human seminal plasma on tumour-associated immunity in patients with adenocarcinoma of the prostate. 741 23

The human prostate has a dual function in that it produces a number of secretory compounds conditioning the urethral surface for sperm passage and acting on spermatozoa as well as on vesicular coagulation proteins (semen liquefaction). In addition to differentially distributed and regulated steroid hormone receptors in epithelium and stroma, the prostate contains a large number of growth factors and their receptors. An incompletely understood paracrine regulation of growth and differentiation exists between epithelial cells, such as secretory, basal and neuroendocrine cells, as well as the underlying stroma (smooth muscle cells, fibrocytes). The presently available (malignant and non-malignant) prostatic cell lines have a number of disadvantages that render them of limited value in prostate cancer research.
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PMID:[Current aspects on morphology and functions of the prostate]. 751 Dec 62

Generally it is believed that mammalian sperm mature during their transit through the whole epididymis. However spermatozoa aspirated from the epididymal duct or vasa defferentia have been recently reported to move actively in azoospermic patients with seminal tract obstruction. We examined whether the testicular sperm move which would provide useful information in the diagnosis of male infertility. Testicular biopsy materials were obtained from 38 testes of 37 patients as follows; 19 cases with azoospermia, 11 with oligozoospermia, and 8 orchiectomized for prostatic cancer (3), testicular cancer (2), epididymal abscess (1), and cryptorchid (2). All materials were obtained from either open biopsy or from the normal portion of the orchiectomized testis. The material was minced with a sharp knife or scissors in an Eppendorf tube containing Ham's F12 solution. Then a couple of drops of sperm suspension were placed on a warmed (37 degrees C) slide glass which was then covered with a coverglass. The prepared slide was immediately examined by phase-contrast microscopy. Another part was used for preparing a touch smear for confirming the presence of testicular sperm and then was fixed in Bouin's solution and stained with H-E. Spermatogenesis was evaluated by Johnsen's mean score (JMS). Eleven of the 19 azoospermic cases revealed the presence of testicular sperm, and ten of them demonstrated the presence of motile sperm. The mean JMS in these cases was 8.8 (normal spermatogenesis). After surgical exploration or vasography, these patients were diagnosed with obstructive azoospermia (post-vasectomy (4 cases), congenital absence of vas deferens (2 cases), secondary epididymal duct obstruction (4 cases)).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Significance of the motile sperm presented in the testis]. 759 83

Human epididymal spermatozoa taken from caput, corpus, and cauda were investigated to determine their fertilizing capacity (22 epididymides from 11 patients who had undergone orchidectomy because of prostatic cancer). The following functions, which have been reported to correlate positively with the fertilization rate, were determined: motility and progressive motility, chromatin condensation (assessed by aniline blue staining), acrosin activity, and induction of acrosome reaction by low temperature. In addition, stimulation of motility by pentoxifylline and phosphatidylcholine was examined. The results showed that motility, progressive motility, normal chromatin condensation, and inducible acrosome reaction increased from the caput to the cauda epididymidis, whereas acrosin activity was normal in all sections. Stimulation of progressive motility, especially that of caput spermatozoa, could be achieved by both pentoxifylline and phosphatidylcholine, the latter being definitely superior. In conclusion, our study confirmed that human spermatozoa in physiological status undergo several steps of maturation during the epididymal transit. Stimulation of sperm motility by phosphatidylcholine may be helpful for patients in whom epididymal spermatozoa are used for assisted reproduction.
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PMID:Function of human epididymal spermatozoa. 772 72

Methods of male contraception that have been developed so far have mainly focused on the inhibition of spermatogenesis through suppression of the hypothalamo-pituitary secretion of gonadotrophins, and simultaneous supplementation with androgens. These methods include the use of combinations of progestogens or luteinizing hormone-releasing hormone antagonists and testosterone derivatives, or high dose testosterone. Though effective contraception can be obtained, side-effects and/or the high cost of treatment limit the widespread use of these approaches. Inhibition of sperm maturation in the epididymis, or direct interference with spermatogenic cells or the cells of Sertoli by e.g. gossypol have been abandoned because of toxic side-effects. Voluntary sterilization by vasectomy is the most commonly used method of male contraception, but its surgical nature, problematic reversibility and suspected link with subsequent prostate cancer render the method far from ideal. Non-surgical vas occlusion may overcome some of these problems, but data on long-term side-effects and reversibility are lacking. New contraceptive developments should focus on interfering with highly specific aspects of spermatogenesis such as unique enzymatic processes and intercellular communication through cytokines, or application of antibodies against antigens of the epididymis or the spermatozoa. Only through better understanding of normal and pathological spermatogenesis will it be possible to develop an acceptable male contraceptive.
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PMID:Male contraception: hormonal, mechanical and other. 804 7


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