Two weeks ago, I told you about a radical new idea, "Fighting Cancer With Common Cold?" (you can check the comments on Slashdot). Now, researchers at the Weizmann Institute, in Israel, came with a similar idea: selectively kill cancer-infested cells while leaving the healthy ones untouched. The chemical they used, the allicin, gives garlic its aroma and flavor. It gives an all-new meaning to garlic as protecting you from the vampires.
Allicin was known for a long time, but until now, it was unstable, and toxic to every kinds of cells.
The researchers have solved both these problems by designing an ingenious delivery method that works with the pinpoint accuracy of a smart bomb. Their findings were reported in the December issue of Molecular Cancer Therapeutics.
Here is a diagram showing how a cancer-infested cell is killed when the allicin molecules enter the sick cell (Credit: Weizmann Institute).
To zero in on the targeted tumor, scientists took advantage of the fact that most types of cancer cells exhibit distinctive receptors on their surfaces. An antibody that is "programmed" to recognize the tumor's characteristic receptor is chemically bound to the enzyme, alliinase. Injected into the bloodstream, the antibody seeks out these cells, and lodges itself and its passenger enzyme on the tumor cells. The scientists then inject the second component, alliin, at intervals. When it encounters the alliinase, the resulting reaction turns the normally inert alliin molecules into lethal allicin molecules, which penetrate and kill the tumor cells. Due to the precise delivery system, neighboring, healthy cells remain intact.
The method is not ready for human experimentation yet.
Using this method, the team succeeded in blocking the growth of gastric tumors in mice. The tumor-inhibiting effects were seen up to the end of the experimental period, long after the internally produced allicin was spent. The scientists note that the method could work for most types of cancer, as long as a specific antibody can be customized to recognize receptors unique to the cancer cells. The technique could prove invaluable for preventing metastasis following surgery.
Another day, another astounding discovery to fight cancer!
Source: Weizmann Institute, via EurekAlert!, December 29, 2003