Australian scientists kill cancer cells with "trojan horse"

"We are playing the rogue cells at their own game. They switch-on the gene to produce the protein to resist drugs, and we are switching-off the gene which, in turn, enables the drugs to enter."

DISARMING TUMOUR CELLS

RNA interference, or RNAi, is designed to silence genes responsible for producing disease-causing proteins and is one of the hottest areas of biotechnology research. RNA was the basis of the 2006 Nobel Prize in medicine.

Dozens of biotechnology companies are looking for ways to manipulate RNA to block genes that produce disease-causing proteins involved in cancer, blindness or AIDS.

Brahmbhatt said that after treatment with conventional drug therapy, a large number of cancer cells die but a small percentage of the cells can produce proteins that make cancer cells resistant to chemotherapeutic drugs.

"Consequently, follow-up drug treatments can fail. The tumors thus become untreatable and continue to flourish, ultimately killing the patient," said Brahmbhatt.

"We want to be part of moving toward a time when cancers can be managed as a chronic disease rather than being regarded as a death sentence," he said.

The Nature report said the mini-cells were "well tolerated with no adverse side effects or deaths in any of the actively treated animals, despite repeated dosing."

"Significantly, our methodology does not damage the normal cells and is applicable to a wide spectrum of solid cancer types," said MacDiarmid.