Transgenic Rat Models for Breast Cancer Research

The laboratory rat is an important model for studying breast cancer due to the many similarities - in this disease between rats and humans. However, limited knowledge in manipulating the rat genome - through transgenesis has prevented researchers from answering important questions in breast cancer - research as well as in research on other human cancers. We proposed to carry out a series of detailed - studies to optimize the many variables in transgenic manipulation, to extend transgenic rat technology to - inbred rat strains, and to develop rat embryo cryopreservation. We have determined that removing - glucose from the microinjection medium and adding cytochalasin for microinjection facilitate transgenic - rat production. We have further developed a procedure for rapid and efficient cryopreservation of rat embryos that results in our ability to recover about half of frozen embryos as viable pups after transfer into pseudopregnant recipient rats. The particular DNAs we selected for our studies on optimizing - transgenic rat production were ones that would likely generate new important rat models for breast - cancer research. As a consequence of our many optimization studies, new transgenic rats models have - been generated for addressing the roles of the neu and ras oncogenes and the growth factor TGF alpha in - breast cancer.