Breast Cancer Lead: Overactive gene is linked to disease

Science News Online ^ | June 16, 2007 | Patrick Barry

[neverdem]

Researchers have discovered a new breast cancer gene that's overly active in 30 to 40 percent of women with the disease. The high percentage makes the malfunctioning of this gene, called I-kappa-B kinase epsilon (IKBKE), one of the most widespread genetic traits among breast cancer patients, says William C. Hahn, coleader of the research team at the Broad Institute in Cambridge, Mass. Their study appears in the June 15 Cell.

Most cancer-related mutations are present in less than 10 percent of women with breast cancer, and only a few important ones characterize as much as 30 percent of that population.

The discovery gives drug companies a significant new target for breast cancer drugs. In addition, the study proved the value of a novel way for scientists to screen any kind of tumor for key cancer-causing mutations.

IKBKE is normally active only in immune system cells, where it helps trigger a response to invading viruses. It has no known function in healthy breast cells, but if a DNA mutation causes the gene to become active, it may signal a cell to proliferate out of control.

The team used a three-step screening process to find the gene. First, the scientists injected each of 354 candidate enzymes into normal, cultured breast cells to see which enzymes would induce cancer. Five of them did so. Then the group checked whether the genes that make those five enzymes were overly active in cells taken from tumors in 30 breast cancer patients. Of the genes, only IKBKE showed elevated activity, and this occurred in 30 percent of the patients' cancers. The researchers then studied tumors from 200 other breast cancer patients and found the enzyme produced by IKBKE in 40 percent of the samples.

In the third step, Hahn's team blocked the gene with a snippet...

[RedMonqey]

Must be one of those “junk genes” some scientists claim .