Stimulation of DNA synthesis by prolactin in human breast tumor explants. Relation to prolactin receptors.
Breast-cancer tissue from 38 patients was tested for prolactin sensitivity by measuring both 16-hour (3H)dT incorporation in tissue fragments during 24-hour organ cultures, and prolactin receptors in tumor specimens. We observed a stimulation of DNA synthesis by prolactin in 6/38 (16%) cases; the stimulation was maximum with physiological concentrations of prolactin (0.05 to 0.2 microgram/ml medium). The stimulation of DNA synthesis never occurred in the absence of prolactin receptors. There is no relation between the response to prolactin and estradiol or progesterone receptor levels, but in four cases the stimulation was observed when the three receptors were present. Finally, the response to the stimulation was independent of the clinical stage of the patient.
D001943:Breast Neoplasms / Q000032:analysis / Q000378:metabolism* / Q000473:pathology; D004273:DNA, Neoplasm / Q000096:biosynthesis*; D005260:Female; D006801:Humans; D011388:Prolactin / Q000494:pharmacology*; D011956:Receptors, Cell Surface / Q000032:analysis*; D011959:Receptors, Estradiol / Q000032:analysis; D011980:Receptors, Progesterone / Q000032:analysis; D011981:Receptors, Prolactin; D013936:Thymidine / Q000378:metabolism
D004273:DNA, Neoplasm; D011956:Receptors, Cell Surface; D011959:Receptors, Estradiol; D011980:Receptors, Progesterone; D011981:Receptors, Prolactin; D011388:Prolactin; D013936:Thymidine