By Ofri Ilani, Haaretz Correspondent
Tags: cancer, Tel Aviv University
Israeli scientists have identified a substance that can kill cancerous cells without harming healthy ones, paving the way for more effective cancer treatment.
The findings by researchers at Tel Aviv University and Sheba Medical Center, Tel Hashomer, were published in the current issue of the international peer-reviewed journal Breast Cancer Research.
"We actually found the Achilles heel of the cancer cell," said Prof. Malka Cohen-Armon from Tel Aviv University, who headed the research team. "As soon as you can target cancerous cells without killing healthy ones, you can produce medications that would cause a lot less suffering to the patient. We can even give a much more aggressive treatment without worrying about harming healthy tissues."
The substance identified by the researchers, which delays cell proliferation in healthy and cancerous cells, is a component of a drug developed a decade ago to preserve nerve cells and prevent them from dying after a stroke.
But while the drug causes the rapid death of cancer cells, healthy cells activate a mechanism that overcomes the delay in proliferation within hours, and those cells continue to proliferate exactly like cells not exposed to the substance.
Cohen-Armon said the drug's effectiveness in treating cancer cells was discovered accidentally.
"I'm not even a cancer researcher," she said. "But two years ago an article we published on various functions in the cell got me interested in cancer cells."
She said the scientists involved in the discovery - who include doctoral student Asher Castiel and Professor Shai Izraeli's research group at the Sheba Cancer Research Center - haven't figured out why the drug affects the cells the way it does.
"We don't even fully understand why this is happening, but we see cancerous cells die and healthy cells overcome this obstacle," said Cohen-Armon. "They somehow find a way to proliferate even in the presence of the substance."
She said the drug was tested on several types of cancer, but so far only the breast cancer tests results have been published.
The experiment has been carried out on female mice, which were injected with human cancerous cells. The substance was gradually released over two weeks. The mice that weren't treated with the substance developed malignant tumors - but in those that got the treatment, the substance either prevented or significantly stalled the development of the cancerous cells.
The experiments did not find any changes in the behavior of the mice treated with the substance.
One of the obstacles to applying the discovery to all forms of cancer is that the medicine is registered as a patent of an American pharmaceutical company. Tel Aviv University's technology transfer company, Ramot, has secured a usage patent enabling it to develop the drug to treat only breast cancer.
The future development of the drug depends on the goodwill of the American company, or on another company developing a similar substance.
"We really want to develop this drug, but there are some completely non-scientific obstacles," Cohen-Armon said. "I hope the research doesn't fade away because of that."