Defining the Steps in a Multistep Mouse Model for Mammary Carcinogenesis
- H.E. Varmus*,†,‡,§,
- L.A. Godley†,‡,
- S. Roy†,
- I.C.A. Taylor†,
- L. Yuschenkoff§,
- Y.-P. Shi**,
- D. Pinkel**,
- J. Gray**,
- R. Pyle§§,
- C.M. Aldaz‡‡,
- A. Bradley††,
- D. Medina***, and
- L.A. Donehower§§
- *Office of the Director, National Institutes of Health, Bethesda, Maryland 20892; †Varmus Laboratory, National Cancer Institute, Bethesda, Maryland 20892; ‡Department of Biochemistry and Biophysics, §Department of Microbiology and Immunology, and **Division of Molecular Cytometry, Department of Laboratory Medicine, University of California, San Francisco, California 94143; ††Institute for Molecular Genetics and Howard Hughes Medical Institute, Baylor College of Medicine, Houston, Texas 77030; ‡‡Department of Carcinogenesis, University of Texas M.D. Anderson Cancer Center-Science Park, Smithville, Texas 78957; §§Division of Molecular Virology, and ***Department of Cell Biology, Baylor College of Medicine, Houston, Texas 77030
This extract was created in the absence of an abstract.
Excerpt
Cancers arise through alterations in two general classes of genes, tumor suppressor genes and proto-oncogenes. Because cancers do not appear to develop from the derangement of a single gene, but instead require a series of changes in genes from both of these two groups, cancer development is referred to as “multistep tumorigenesis.” For a few systems, such as colon cancer, a reasonable consensus exists as to which mutations occur and in what sequence (Fearon and Vogelstein 1990). Presently, many laboratories are attempting to understand which genetic changes are responsible for breast cancer, one of the most common forms of human cancers.
Mutations of tumor suppressor genes occur frequently in human breast cancer. For example, the retinoblastoma gene (Rb) undergoes somatic mutation during the development of some human breast cancers (Weinberg 1992). p53, the gene most commonly mutated in all human cancers, is mutated or deleted in at least 22% of...
