A New Insulin-Like Growth Factor Binding Protein (mac 25) and Its Role in Breast Cancer and Cell Growth Control
Abstract
Mac25 is the seventh member of the IGFBP family (IGFBP-7). IGFBP-7 is expressed in normal human mammary epithelial cells (HMECs) and upregulated in senescent HMECs. IGFBP-7 is not expressed in twelve of sixteen breast cancer cell lines, in studies by two laboratories. Its expression is absent in estrogen receptor positive (ER+) breast cancer cell lines. IGFBP-7 may regulate HMEC growth. We will test the hypothesis that it suppresses growth in ER+ breast cancer cells. We will also test the ability of IGFBP-7 to negatively affect growth rates in ER+ breast cancer cells by transducing the cDNA into normal and human breast tumor cultures using a retroviral vector system. We will determine if IGFBP-7 is regulated at the transcriptional level by characterization of the promoter region of the gene. We will determine binding properties of IGFBP-7 protein by gel shift analysis of protein extracts and anti-IGFBP7 antibody. We will determine if IGFBP7 is hormonally regulated by studying tissue specificity of RNA expression and protein localization through in situ hybridization and immunohistochemistry (additional aim).
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1997
- Accession Number
- ADB233747
Entities
People
- Heather-marie P. Wilson
- Karen Swisshelm
Organizations
- University of Washington