Steroid receptor proteins and regulation of growth in mammary tumors.
The failure of the estrogen receptor test to predict unequivocally whether a breast cancer will respond to endocrine therapy has prompted us to re-examine the spectrum of responses that might be expected in a hormone-sensitive tissue. Three basic responses are recognized; initiation of DNA synthesis and cell proliferation; negative feedback; and autophagia. The expression of these responses may be partly or totally deficient in tumors. In some tumors, resistance to hormone may result from the lack of entry of hormone into the nucleus; in others the interaction of hormone with chromatin is probably abnormal Evidence is presented in support of the idea that the presence of steroid in the nucleus is strongly correlated to the presence of cytoplasmic receptor. The results also suggest that there is a strong link between the presence of steroid in the nucleus and the initiation of DNA synthesis. Finally the disappearance of nuclear receptor and the onset of autophagia seem to be related catabolic events.
D000728:Androgens / Q000378:metabolism; D000818:Animals; D001943:Breast Neoplasms / Q000378:metabolism* / Q000503:physiopathology / Q000628:therapy; D002455:Cell Division; D002467:Cell Nucleus / Q000378:metabolism; D002843:Chromatin / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004273:DNA, Neoplasm / Q000096:biosynthesis; D004195:Disease Models, Animal; D005246:Feedback; D005260:Female; D005796:Genes; D006728:Hormones / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008325:Mammary Neoplasms, Experimental / Q000378:metabolism; D051379:Mice; D011467:Prostate / Q000502:physiology; D051381:Rats; D011944:Receptors, Androgen; D011960:Receptors, Estrogen; D012038:Regeneration; D013737:Testis / Q000502:physiology
D000728:Androgens; D002843:Chromatin; D004273:DNA, Neoplasm; D006728:Hormones; D011944:Receptors, Androgen; D011960:Receptors, Estrogen