Cell Cycle Controller Chemical Combats Cancer

There are many types of cancer preying upon the human population, and nearly as many different therapeutic approaches to mitigating malignancies. But what if one drug could cure them all? Cancers do share similar features: relatively rapid cell division, and undifferentiated histologic features. Researchers at Tel Aviv University have found a drug that "arrests" the cell cycle in malignant cells -- preventing them from multiplying. The effect was proven with human breast cancer tissue that had been implanted into mice.

Prof. Malka Cohen-Armon of TAU's Sackler School of Medicine found that the stroke drug –– a member of a family of phenanthridine derivatives developed by an American drug company –– worked to kill cancer in mice which had been implanted with human breast cancer cells.

"Not only did the drug kill the cancer, but when we investigated normal cells, we discovered that they'd reacted as though they hadn't come in contact with the drug," says Prof. Cohen-Armon. "This is the result we were hoping for. If human trials go well, we could have an entirely new class of drugs in our hands for the fight against cancer."

Stopping the deadly cycle of cancer cell growth

The immediate results of the study were only one of the promising findings in her research, she notes. The team also discovered a molecular mechanism in the cell cycle that can be arrested only in human cancer cells. This cell cycle arrest, they report, causes the cancer cells to die without affecting normal human cells.

"We've found a molecular triggering mechanism in cancer cells that, when set off, causes the cancer cells to die ― they just stop multiplying and die within 48 to 72 hours. Normal, healthy body cells are only temporarily arrested by the same mechanism ― they overcome this cell cycle arrest within 12 hours and continue to proliferate in the presence of the drug as normal un-treated cells," says Prof. Cohen-Armon. "All the human cancer cells we tested seemed to succumb to this compound."

She adds that, even if this particular drug doesn't reach the market to fight against cancer, an entirely new class of drugs might be built around mechanism the team has revealed.

Different strokes

The stroke drug was initially developed to prevent nerve cell death during inflammation and tissue damage in the brain after stroke. However, in pre-clinical studies, American researchers found that these compounds didn't work as well as they'd hoped. Today they are used only for research purposes in laboratory settings.

"The compound we used," says Prof. Cohen-Armon, "presented no traces of toxicity in mice. With this compound, we were able to show how one of the many molecular mechanisms regulating the cell cycle can be targeted, and the proliferation of cancer cells halted." The team is currently working to identify all the regulatory mechanisms involved in this specific process and hope that, in better understanding the science, they might point the way to a new class of anti-cancer drugs. _MachinesLikeUs

Selective killing of cancer cells, while leaving normal cells unharmed, is the holy grail of all cancer therapists and researchers. If the TAU researchers have truly discovered a mechanism of arresting the growth of cancer cells selectively, and killing them without causing harm to the host organism, they may be quite close to finding a "cure-all" for cancer. Most types, anyway.

This is how the future slips up, almost unannounced. Such revolutions are hardly ever trumpeted on approach, but rather acknowledged belatedly in hindsight. Meanwhile, the world's leaders prance around Copenhagen as if what they were doing actually meant anything. Life in an idiocracy.