Role of Mammary Prolactin in Carcinogenesis
Abstract
Prolactin (Prl) is a mitogenic hormone that shares characteristics with growth factors. Recent reports that rat mammary tissue expresses PRL mRNA led us to hypothesize that PRL acts as an autocrine/paracrine growth factor in the mammary gland, and may be a determinant in mammary carcinogenesis. To examine this, mammary tumors were induced in rats by injecting the carcinogen nitrosomethylurea (NMU). In vitro studies utilized an NMU-derived mammary tumor cell line. The mammary tumors and the cell line express niRNA for both PRL and PRL receptor, as assessed by reverse transcriptase (RT)-PCR. Immunoreactive PRL was detected in the NMU-induced tumors. NMU cells were cultured with PRL antiserum. The PRL antiserum inhibited cell proliferation 40-50% as compared to normal rabbit serum (NRS) or GM antiserum. In summary, we have shown that NMU-induced mammary tumors express rnRNA for PRL and PRL receptor. The addition of PRL antiserum to cultured NMU cells inhibited their growth. We propose that PRL may be acting as a local growth factor that stimulates proliferation of mammary tumors.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1995
- Accession Number
- ADA301702
Entities
People
- Nira Ben-jonathan
Organizations
- University of Cincinnati