Causes, Inheritance: Many steps to cancer, Vogelstein clip 1
Professor Vogelstein explains that colon cancers provide a good example of a type of tumor in which the genetic steps leading from the normal colon epethelial cell to a cancer, are reasonably well known.
Bert Vogelstein, M.D. is a Howard Hughes Medical Institute Investigator and the Clayton Professor of Oncology and Pathology at Johns Hopkins University. His research focuses on the identification and characterization of genes that cause colon cancer. This has led to the discovery of the APC gene â€“ the "gatekeeper" in colon cancer development. â€œColon cancers provide a good example of a type of tumor in which the genetic steps leading from the normal colon epethelial cell to a cancer, are reasonably well known. And it's important to point out that this is not a speedy process, it generally takes 20 to 40 years to get from a normal cell to a malignant tumor; a malignant tumor is the same as a cancer, it's just another name. And the reason it takes that long is because it requires all these mutations and in cells that have intact repair systems, it takes decades to develop all these mutations sequentially. In a patient who has an defective mismatch repair system it takes a much shorter period of time, which is why patients with Non-polyposis form of colon cancer develop it at an earlier age.â€œ
defective mismatch repair, bert vogelstein, howard hughes medical institute, cause colon cancer, johns hopkins university, colon cancers, genetic steps, malignant tumor, colon cancer, cancer development, mutations, inheritance, oncology, cancer
- ID: 976
- Source: DNALC.IC
Professor Vogelstein explains that APC is expressed in all cells, and that we don't know why it only causes cancers when mutated in the colon and in a few other places.
In Familial Adenomatous Polyposis, a complex cascade of events leads from an initial mutation in a “gatekeeper” gene, eventually to a malignant tumor.
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Professor Vogelstein explains that the only difference between a benign tumor and a malignant tumor is not the size, it's the ability of the malignant tumor to invade, and get through the tissues.
Professor Vogelstein, explains that cancer is in essence a genetic disease. But it's really quite different than all the other genetic diseases that people usually think of when they think about a genetic disease.
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Professor Bert Vogelstein, explains that cancer is in essence a genetic disease. It is caused by mutations of genes and there are three types of genes, that contribute to cancer.
Mary-Claire King speaks about how much was yet to be understood about the genetic mechanisms of cancer when she began her hunt for genes associated with breast cancer.
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