Scientists suggest light approach to cancer therapy

In collaboration with the Press Association

Scientists have said that treating cancer cells with a substance that causes them to emit light could be used to trigger light-sensitive drugs and prevent damage to healthy tissue.

The method combines two existing technologies, with initial testing in the laborartory being used to target leukaemia cells.

"Essentially what we're working on is targeted drug delivery, a system that allows the targeting of drugs to a particular cell," said lead researcher Dr Michael Firer.

Previous light-sensitive delivery systems for cancer have been activated by shining laser light from outside the body.

This still leaves some treatment "overspill", with some healthy cells still unavoidably targeted and meaning that use has until now been limited to skin cancers close to the surface of the body.

"It's an invasive process, and not entirely successful in reaching the required area," Dr Firer told website Israel21c.

"What is presently done is to attach a laser fibre to a catheter which enters the body through the mouth or another way, and try to reach where the cancer is and eradiate it that way."

The current research has sought to get around this problem by making the cancer cells the source of light, drawing on a long-known light-producing chemical reaction.

Initial testing in laboratory cancer cells and in animal models has shown that treating cancer cells with a light sensitive compound known as luminal creates light.

When these cells were treated with light-sensitive drugs the researchers found that they were able to kill of 95 per cent of cancer cells.

"This means that we might be able to use photodynamic therapy to treat tumours deep inside the body that external light sources cannot reach," Dr Firer added.

The study was carried out by the College of Judea and Samaria in Israel and published in Cancer Research UK's medical publication, the British Journal of Cancer.