Quest for genes that stop cancer spread.

Quest for genes that stop cancer spread

Once again, scientists expect to add to the list of genes that play a part in the development of cancer. First they found oncogenes, which stimulate tumor development, then tumor suppressor genes, so named because they normally keep uncontrolled cell growth in check. Next came a metastasis suppressor gene, called nm23, which could keep cancer from spreading. Now it seems that an unidentified gene on chromosome 6 regulates nm23, says Danny R. Welch at Pennsylvania State University College of Medicine in Hershey.

Welch and his colleagues first noticed missing pieces of that chromosome in many of the cells from people whose melanoma, a skin cancer, had spread to other parts of their bodies. He then used a technique called microcell-mediated cell transfer to add chromosome 6 to melanoma cells growing in a laboratory dish. He injected those altered cells into specially bred mice. Those mice developed tumors as expected, but the tumors never spread from the original site, Welch reports.

"This is the first evidence in which metastasis is completely suppressed by the addition of genetic material," he says. But now he needs to pinpoint the gene exerting this effect. He hopes that replacing that gene in people who lack it could prevent a tumor's spread.