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

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

Antioxidant defenses play a critical role in the regulation of programmed cell death, even when death is induced by nonoxidative stimuli. During spermatogenesis, most of the testicular germ cells degenerate by an apoptotic process that is under hormonal control. However, the exact mechanisms by which hormonal signals are transduced within the cells to direct their life, and whether other effectors of the apoptotic pathway, for example antioxidants, take part in the control of human germ cell survival, are not known. In the present study, testosterone and N-acetyl-L-cysteine (NAC), which is an antioxidant, an inhibitor of apoptosis in several systems, and a survival factor in human semen, were found to suppress programmed cell death in human testicular germ cells in vitro. The samples came from adult men undergoing orchidectomy for prostate cancer. Germ cell death was induced by incubating segments of seminiferous tubules under serum-free culture conditions. This apoptosis, detected by Southern blot analysis of DNA fragmentation, by DNA labeling in situ, and by morphological analysis under the electron microscope, was significantly inhibited by testosterone at concentrations of 10(-6) and 10(-7) mol/L. NAC concentrations of 125, 100, 50, and 25 mmol/L suppressed germ cell death in a dose-dependent manner. This inhibition was effective during 4, 24, and 48 h of incubation. Apoptotic cells were identified mainly as spermatocytes and early spermatids. Programmed cell death was also demonstrated in late spermatids. We conclude that NAC, which is an antioxidant, plays an important role in germ cell survival in the human seminiferous tubules in vitro. We also suggest NAC as a possible new therapeutic factor for some men with idiopathic oligospermia.
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PMID:N-acetyl-L-cysteine inhibits apoptosis in human male germ cells in vitro. 966 38

Andropause, a syndrome in aging men, consists of physical, sexual, and psychologic symptoms that include weakness, fatigue, reduced muscle and bone mass, impaired hematopoiesis, oligospermia, sexual dysfunction, depression, anxiety, irritability, insomnia, memory impairment, and reduced cognitive function. Free testosterone levels begin to decline at a rate of 1% per year after age 40 years. It is estimated that 20% of men aged 60-80 years have levels below the lower limit of normal. Although the causal relationship between declining testosterone levels and development of andropause symptoms is not firmly established, administration of testosterone to this population resulted in improvements in many areas. Most studies to date focused on physical benefits of testosterone replacement and failed to assess psychologic symptoms rigorously. Preliminary data suggest that therapy may benefit elderly men with new-onset depression. Testosterone administration is not without problems, the most worrisome being the potential for increased prostate cancer risk. Despite this concern, a limited number of studies administered the hormone weekly for up to 2 years, with only mild increases in prostate-specific antigen over control values. Currently, insufficient evidence, primarily regarding psychologic safety and efficacy, exists to warrant general administration of testosterone to elderly hypogonadal men. Further clinical investigations of this therapy in men with low testosterone levels and andropause symptoms are justified and necessary.
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PMID:Testosterone and andropause: the feasibility of testosterone replacement therapy in elderly men. 1045 66

In France, 12 to 15% of couples experience procreation difficulties. A disorder of spermatogenesis (oligospermia, azoospermia) is responsible in 1/3 of cases. These forms of infertility, labelled idiopathic, probably have a genetic component, like microdeletions of the Y chromosome. The normal rate of circulating androgens suggests the implication, in some cases, of an abnormality from the receptor to the androgens (RA) of these male infertilities, whose number remains to be defined. Point mutations on exons of the gene encoding the AR cannot account for all cases of infertility due to idiopathic disorders of spermatogenesis. Expansion of the number of CAG triplets of exon 1 of the AR gene, already demonstrated in a fatal degenerative neuropathy (Kennedy's disease, in which more than 50% of patients are infertile), has been detected in these cases of idiopathic infertility and would be responsible for AR dysfunction. The number of these triplets is also decreased in patients with androgen-dependent prostate cancer. The polymorphism of repetition of CAG triplets would therefore be responsible for fine adjustment of the AR between excessive and insufficient function. ICSI. (Intra-Cytoplasmic Sperm Injection) is currently proposed in these cases of infertility, but the consequences of transmission of these abnormalities to the offspring are unknown.
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PMID:[Idiopathic male infertility and androgen receptors]. 1176 79

The androgen receptor (AR) mediates the effects of male sexual hormones on development and physiology. Alterations in AR function are central to reproductive disorders, prostate cancer, and Kennedy disease. AR activity is influenced by post-translational modifications, but their role in AR-based diseases is poorly understood. Conjugation by small ubiquitin-like modifier (SUMO) proteins at two synergy control (SC) motifs in AR exerts a promoter context-dependent inhibitory role. SC motifs are composed of a four-amino acid core that is often preceded and/or followed by nearby proline or glycine residues. The function of these flanking residues, however, has not been examined directly. Remarkably, several AR mutations associated with oligospermia and androgen insensitivity syndrome map to Pro-390, the conserved proline downstream of the first SC motif in AR. Similarly, mutations at Gly-524, downstream of the second SC motif, were recovered in recurrent prostate cancer samples. We now provide evidence that these clinically isolated substitutions lead to a partial loss of SC motif function and AR SUMOylation that affects multiple endogenous genes. Consistent with a structural role as terminators of secondary structure elements, substitution of Pro-390 by Gly fully supports both SC motif function and SUMOylation. As predicted from the functional properties of SC motifs, the clinically isolated mutations preferentially enhance transcription driven by genomic regions harboring multiple AR binding sites. The data support the view that alterations in AR SUMOylation play significant roles in AR-based diseases and offer novel SUMO-based therapeutic opportunities.
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PMID:The in vivo role of androgen receptor SUMOylation as revealed by androgen insensitivity syndrome and prostate cancer mutations targeting the proline/glycine residues of synergy control motifs. 2282 93