The function of prolactin in human breast cancer was studied using four different approaches. First, purification and characterization of the prolactin receptor from breast cancer cells indicated that the receptor has a molecular mass of 88 000 Da, 67 000 Da being protein, and the other 21 000 Da presumably carbohydrate. Secondly, prolactin was tested for mitogenic activity in breast cancer in vitro. No consistent mitogenic response to prolactin could be demonstrated in these experiments. Thirdly studies upon the regulation of the prolactin receptor in breast cancer cells indicated that the prolactin receptor is stimulated by lactogen, estrogen and progesterone at the protein level. Estrogen, progesterone, thyroid hormone, and forskolin (but not lactogen) increase prolactin receptor steady state RNA levels, and the phorbol ester PMA and retinoic acid inhibited receptor RNA levels. However, effects at the RNA level were of a much lesser magnitude than effects at the protein level. Mechanisms other than transcriptional regulation alone are likely involved in prolactin receptor regulation. Fourthly, prolactin receptor and prolactin inducible protein/gross cystic disease fluid protein (PIP/GCDFP-15) RNA levels were examined in breast cancer tumors. Highly significant correlations were observed between the prolactin receptor and the progesterone receptor; the prolactin receptor and PIP/GCDFP-15; and PIP/GCDFP-15 and progesterone receptor.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.41006 |
| Date | January 1992 |
| Creators | Gould, David R. (David Ross) |
| Contributors | Kelly, P. A. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Division of Experimental Medicine.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001319727, proquestno: NN87839, Theses scanned by UMI/ProQuest. |
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