Browsing by Subject "Steroids"

Now showing 1 - 2 of 2
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    Hyperactive androgen receptor in prostate cancer, what does it mean for new therapy concepts?
    (Murcia : F. Hernández, 1997) Culig, Z.; Hobisch, A.; Hittmair, A.; Radmayr, C.; Peterziel, H.; Bartsch, G.; Cato, A.C.B.; Klocker, H.
    Investigations on androgen signaling alterations in the late stages of prostate cancer revealed new molecular mechanisms that may be in part responsible for failure of endocrine therapy. Both primary and metastatic lesions from prostate cancer express androgen receptor protein. Amplification of androgen receptor gene occurs in a subset of prostate cancer patients. Several point mutations of androgen receptor gene have been described; they generate receptors which are functionally activated by androgens, other steroids, and even by antihormones. The frequency of androgen receptor mutations may be high in tumor metastases. Functional activity of androgen receptor is influenced by nonsteroidal factors, such as peptide growth factors and second messengers. Thus, prostate cancer cells adapt to low androgen environment by various mechanisms utilizing androgen receptor. Therefore, new strategies for switching off the androgen receptor are needed.
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    Steroid receptors in human ejaculated sperm as molecular markers of the detrimental effects related to the pathophysiology of testicular varicocele
    (Universidad de Murcia. Departamento de Biología Celular e Histología, 2016) Perrotta, Ida; Aquila, Saveria
    The exact physiopathologic effect of testicular varicocele on male fertility is not defined yet. The detrimental role of the varicocele in fertility is supported by the presence of a higher frequency of affected men among the infertile population. However, the mechanism/s by which a varicocele impairs sperm production, structure and function, is not known. In spite of active interest, our understanding of the human male gamete ultrastructural molecular organisation is still incomplete and therefore our knowledge of the sperm molecular anatomy is very limited. The presence of steroid binding sites on human spermatozoa has been evidenced since the 1970s, and afterwards, spermatozoa physiology was linked to the action of different steroids. The presence of steroid/steroid receptor systems was demonstrated in mature spermatozoa as membrane but also as nuclear conventional receptors, suggesting that both systemic and local steroids, through sperm receptors, may influence male fertility. From new data, it emerges that varicocele may induce damage in the male gamete at molecular level, opening a new chapter in the already multifactorial pathophysiology of the varicocele, complicating this issue. In sperm from varicocele, a decreased expression of steroid receptors and a consequent reduced responsiveness to steroids may represent a mechanism involved in the physiopathology of varicocele. Therefore, the modulation of these nuclear receptors pave the way for novel therapeutic opportunities in the treatment of the male pathologies related to human reproduction. The purpose of this review is to gain new insight into the physiopathology of varicocele and to study its impact on human sperm molecular anatomy