Sometimes, research in one field can lead to discoveries in an entirely different one. An example is work carried out at The Hebrew University's Faculty of Agricultural, Food and Environmental Quality new drug treatment for halting the growth and spread of cancer cells.

The approach has been shown to inhibit malignant cells without affecting normal ones, and without the severe side effects of traditional treatments. researchers isolated the malignant tumor from its nutritional and oxygen supplies, thereby halting its growth and stopping metastases from spreading to other parts of the body.

The team - headed by Prof. Oded Shoseyov and including Dr. Levava Roiz, Dr. Patricia Smirnoff and Dr. Betty Schwartz - published their discoveries in the American Cancer Society's journal Cancer.

The HU researchers' approach is based on the actions of actibind, a protein produced by the black mold Aspergillus niger, a well-known microorganism used in biotech and food technology. In plants, actibind binds actin, a major component of the intracellular structure in plants, interfering with the plants' pollen tubes and halting cell growth.

While the researchers were initially interested in the activity of actibind in connection with a horticultural project aimed at improving the quality of peaches and nectarines, an actibind-like protein, RNaseT2, was also found to bind actin in human and animal migrating cells, such as the cells responsible for new blood vessel formation (angiogenesis) in tumors. By blocking the blood supply to the tumors, actibind halted the ability of malignant cells to move through the blood stream to form new metastases. A further benefit is that actibind is not toxic to normal cells.

In lab experiments using cell cultures that originated from human colon cancer, breast cancer and melanoma, increasing the level of actibind was found to reduce the ability of these cells to form tumorogenic colonies. Further experimentation with a variety of animal models showed that increased actibind inhibited the growth of colon cancer-derived tumors, metastases and blood-vessel formation.

The results shown in working with actibind led to a further development in the researchers' project: During the completion of the Human Genome project, the gene encoding for RNaseT2 - the human actibind-like protein - was found on chromosome #6. The researches used genetic engineering procedures to produce a recombinant RNaseT2 protein that showed an impressive anti-cancer potential. These results have raised broad interest in international scientific meetings and in business circles, as actibind and the human RNaseT2 represent the basis for a new class of drugs that could be used as a front-line therapy in the fight against cancer.