cancer may depend on nearby cells

Forty Years' War: Old Ideas Spur New Approaches in Cancer Fight
By GINA KOLATA in the nyTimes
Published: December 28, 2009

The basic idea still in the experimental stages is that cancer cells cannot turn into a lethal tumor without the cooperation of other cells nearby. That may be why autopsies repeatedly find that most people who die of causes other than cancer have at least some tiny tumors in their bodies that had gone unnoticed. According to current thinking, the tumors were kept in check, causing no harm.

It also may mean that cancers grow in part because normal cells surrounding them allowed them to escape. It also means that there might be a new way to think about treatment: cancer might be kept under control by preventing healthy cells around it from crumbling.

Think of it as this kid in a bad neighborhood, said Dr. Susan Love, a breast cancer surgeon and president of the Dr. Susan Love Research Foundation. You can take the kid out of the neighborhood and put him in a different environment and he will behave totally differently.

Its exciting, Dr. Love added. What it means, if all this environmental stuff is right, is that we should be able to reverse cancer without having to kill cells. This could open up a whole new way of thinking about cancer that would be much less assaultive.

Some companies are taking note. Genentech, for example, is investigating the way some skin, ovarian, colon and brain cancers signal surrounding cells to promote cancer growth. The company has an experimental drug that it hopes might block this signaling.

Others are studying drugs like statins or anti-inflammatory drugs that may act by affecting signals between surrounding cells and cancers. But, says Dr. Robert Weinberg, a cancer researcher at M.I.T., this is not a clearly articulated scientific agenda, in large part because we still know too little about these signals and how their release is controlled.

The researchers are cautious. They, more than anyone else, know the blind alleys of cancer research over the past few decades. And no one is suggesting that controlling a tumors environment will, by itself, cure cancer.

And they are not discounting cancer-causing genes. But even some who have made their careers studying cancer genes say a tumors environment can no longer be ignored