In the first large-scale screen of genetic changes in cancer cells, researchers have found that a typical breast or colorectal tumor results from mutations in about 90 genes, with different sets of mutations producing the same type of cancer. But the many different genetic routes to malignancy share common features that point toward new means of cancer prevention, diagnosis, and treatment.
Previous genetic studies of cancer have concentrated on specific genes or on chromosomal regions. In the September 8, 2006, issue of Science, Howard Hughes Medical Institute (HHMI) investigators Bert Vogelstein at Johns Hopkins University and Sanford D. Markowitz at Case Western Reserve University School of Medicine, together with a team of researchers from The Kimmel Cancer Center at Johns Hopkins and other institutions, report on a radically new way of identifying genes involved in cancer.
They analyzed 13,000 genes in 11 breast cancer tumors and 11 colorectal tumors to come up with the 90 genes of interest in cancer. One obvious next step would be to repeat this process for more types of cancer and more instances of each type.
While many mutations and genes are involved they fit into a smaller number of pathways that are crucial for the development of cancers. While not mentioned here I'm guessing genes which are involved in producing signals for angiogenesis (growth of new blood vessels) are in their set of 90 genes.
Despite the complexity of the results, a closer examination of the data has started to reveal an underlying order. Many of the genes that are mutated are involved in pathways thought to be important in cancer, such as cell adhesion, movement, and signaling. Each of these pathways relies on multiple genes, and flaws in any of the genes in a pathway may have similar consequences.
“By taking a systems biology approach to connect these genes, we suspect that the complexity will be less than it appears at first sight,” said Vogelstein. “The same 10 or 20 pathways may be altered in every cancer, though the particular mutated genes in these pathways will be different. The picture will become much clearer as the function of these genes and the ways they interact are better worked out.”
They've identified 90 genes involved in cancer. But they do not know what the proteins do which are made by some of these genes. But they now have identified many genes whose proteins can be studied by cancer research labs.
Technological advances only recently made possible the collection of the data which produced these results.
This kind of study could not have been done a few years ago, said Tobias Sjöblom, an HHMI research associate in Vogelstein's lab, who is the lead author of the Science article. But the availability of the human genome sequence and improvements in sequencing and bioinformatics technologies have made it possible to examine the genome of cancer cells in a comprehensive and unbiased manner, he said.
The rate of biotechnological advance is not slowing. Successively better generations of test equipment and software are both accelerating the rate at which genetic and other biological information can be collected and analysed. The rate of advance in understanding of how cancer works was a snail's pace 30 or 40 years ago. The pace now is much faster. 10 years from now with all the instrumentation and software advances that'll happen in the meantime the rate of advance will be blazing. 20 years from now death from cancer should become rare.
|Share |||Randall Parker, 2006 September 10 10:24 PM Biotech Cancer|