Expression of prolactin receptors in human osteosarcoma cells

The expression of prolactin receptor (PRL-R) mRNA was demonstrated by reverse transcription-polymerase chain reaction (RT-PCR) combined with Southern analysis in total RNA extracts from two human osteosarcoma cell lines (MG-63 and Saos-2). The level of PRL-R transcript was significantly enhanced in cells cultured in the presence of 1,25-(OH)(2) vitaminD(3) (10(-7)M) and to a lesser extent in the presence of dexamethasone (10(-6)M). This first demonstration of PRL-R gene expression in osteoblastlike cells supports the hypothesis of a direct action of prolactin in bone cells, which is further strongly suggested by the stimulatory effect of 1,25-(OH)(2) vitaminD(3) and dexamethasone on PRL-R mRNA level in these cells. (C) 1996 Academic Press, Inc.