This week BMC seminar will be given by Dr. Deborah Roess, Professor at the Department of Biomedical Sciences, Animal Reproduction and Biotechnology Laboratory, Colorado State University. Thursday 13th february at 12:25 in room 343 at Læknagarður.

Title:  Fluorescence Correlation Quantitation of Insulin-like Growth Factor and Insulin Receptor Dimers in Breast Cancer

Abstract: The insulin receptor (IR) and insulin-like growth factor receptor (IGF1R) family is a therapeutic target in oncology. Development of pharmaceuticals that target the IR/IGF1R receptor family has been based on observations suggesting that circulating levels or insulin and/or insulin-like growth factor 1 (IGF-1) are related to cancer risk. In addition, increases in either receptor, present both as IR-IR and IGF1R-IGF1R homodimers and as IGF1R-IR heterodimers may reduce relapse-free survival in breast cancer patients. However, simple increases in the total expression of IGF1R and IR monomers do not adequately explain the growth-promoting effects of IGF-1 on tumor cells.

Rather, it seems that distribution of these receptors among homodimers and heterodimers regulates tumor cell responses to insulin and IGF-1 including cell proliferation and migratory potential. There is currently no direct method to evaluate the concentrations of these individual receptor species in breast cancer cells or, for that matter, in any other normal or cancerous tissue. Fluorescence correlation spectroscopy (FCS) and photon counting histogram (PCH) methods provide a path to such direct measurements.  These methods will provide improved data for quantitative understanding of how IR and IGF1R expression jointly regulate signaling by insulin and IGF-1 in particular cells, understanding of how hormone responses can vary among cell types and may lead ultimately to improved patient care through the use of targeted pharmaceutical agents that appropriately modulate hormone-mediated tumor cell proliferation.