Skip to main content
         

Vol. 07 Issue 3, Early Fall 2002

Modeling Breast Cancer in the Mouse: Introduction
The Ribbon 

Introduction by Barbour Warren, BCERF Research Associate

Cancer formation in the breast is a complex process. Taken most simply, it involves: a) complicated interactions of different parts of the breast, b) exposure of these parts and the developing tumor to a continually changing range of hormones, and; c) the effects of a number of cancer associated genes. Because of this complexity, studies in animals, using what are called animal models, have played an important part in the current understanding of this disease and in the development of various treatments. In this issue of The Ribbon we are fortunate to have a discussion of how mice are currently being used to help understand the role of various cancer genes in breast cancer. The authors are well qualified to present this discussion. Their laboratory helped develop and is actively working with a mouse model which holds great promise for the study of genes which are lost during breast cancer formation.

Cancer formation requires a number of steps. Many of these steps involve changes in genes associated with cancer. These genes are of several types. First are genes that lead to cancer formation and whose function is increased or changed as a tumor forms. Second are the genes that keep cancer growth from happening. These are called tumor suppressor genes and they are lost or inactivated during cancer formation.

As this article succinctly details, study of cancer genes has involved either the addition or the elimination of these genes from various types of laboratory mice. The resulting animals are then studied to understand the biological function of the genes and their part in the formation of cancer. The cancer gene changes made in these mice are present throughout the developmental and adult lives of the animals. This is not optimal for two reasons. First the gene changes can result in developmental abnormalities in the animals. Second, this is different from what occurs in the formation of most human cancers where the changes are thought to happen after birth, and possibly during specific life periods. Drs. Nikitin and Shmidt describe a system their laboratory helped develop which overcomes these two problems. Using this system they are able to produce mice in which they can induce the loss of a tumor suppressor gene at any point during its life and in specific areas of its body. For example, by inducing the loss of tumor suppressor gene in animals of different ages, studies can examine effects of gene inactivation during the various phases of the development of the breast. Further, the change could be made in only some of a given animal's mammary glands, allowing comparison to breasts without the change but exposed to the same environment of hormones and other factors within the animal. This process will undoubtedly lead to advances in the understanding and treatment of breast cancer.

Continue to the Article

Back to the top

Last Update 09.12.02