miércoles, 7 de septiembre de 2011

Colorectal Cancer Genomes Sequenced ► NCI Cancer Bulletin for September 6, 2011 - National Cancer Institute

Colorectal Cancer Genomes Sequenced

Researchers have used whole-genome sequencing to survey the genetic alterations in colorectal tumors and matched normal cells from nine patients with the disease. Among other findings, the researchers identified a fused gene in a small percentage of tumors. As with all such genome projects, the results, published online September 4 in Nature Genetics, are preliminary, and further studies will be needed to capture the extent of genomic changes in this disease.
Dr. Matthew Meyerson of the Dana-Farber Cancer Institute and his colleagues found a range of genomic rearrangements, including exchanges of DNA between and within chromosomes (known as translocations). The researchers identified 11 translocations that could give rise to fusion genes, which are created when DNA from different parts of the genome merges. Specific fusion genes, and the fusion proteins they encode, have been reported in common cancers such as lung and prostate, but little is known about their possible role in colorectal cancer.
One of the 11 gene fusions was of particular interest. The fusion involves the genes VTI1A and TCF7L2, which encodes a transcription factor that regulates the activity of genes that are essential for the proliferation and development of intestinal epithelial cells. In addition, previous research has linked the expression of TCF7L2 to survival in colorectal cancer. Among a set of 97 colorectal tumors the researchers tested, three had this fusion.
To test the functional importance of the VTI1A-TCF7L2 fusion gene, the researchers identified a colorectal cancer cell line that included the fusion. Experiments with these cells suggested that the fusion gene plays a “critical role” in their growth, the researchers found. But they noted that further research is needed to understand what role, if any, the gene may play in the disease.
The discovery of the VTI1A-TCF7L2 fusion gene shows that “functionally important fusion events occur in this disease and suggest that further structural characteri­zation will likely identify additional new recurrent rearrangements,” Dr. Meyerson and his colleagues concluded.
They noted that large sequencing projects will be needed to catalog the genomic changes in the disease; one such project is The Cancer Genome Atlas.
Further reading: "More DNA Rearrangements Found in Prostate Cancers"
NCI Cancer Bulletin for September 6, 2011 - National Cancer Institute: - Enviado mediante la barra Google

No hay comentarios:

Publicar un comentario