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It's a fierce battle; the lives of thousands are at stake, and the star-ship captain engages the cloaking device, enabling him to, unseen, get up close and personal with the adversary, only to de-cloak at the final moment, lock on phasers and destroy the enemy ship in a flash of light.

This familiar sci-fi scene is one that (albeit on a molecular rather than intergalactic scale) promises to play out in an entirely different battle: that against cancer.

In Star Trek, it was an alien race that developed the famous cloaking device. In the molecular battle, however, it is scientists at Newcastle University who have developed a new technology to 'cloak' cancer-fighting proteins until they are activated by UV light, enabling them to target tumour cells in a more specific and effective way than previously possible.

The proteins in question are specific antibodies. Antibodies are part of the body's immune system. They attach themselves (in keeping with the Star Trek analogy) to 'alien' tissues/cells, and allow the destruction of that tissue. Usually antibodies are involved in the fight against 'alien invaders' such as allergens or infectious disease. However, some have been developed to activate the attack of cancer cells.

The possibilities of these 'therapeutic antibodies' have long been acknowledged, but it has proven difficult to make them specific enough, meaning they trigger the immune system to attack and destroy the patient's own body.

In the early 1990s Prof Colin Self and Dr Steve Thompson realised the potential of UV-activated molecules to create, as Professor Self puts it, "The simplest and safest way of delivering medicine to the site needed". Light is "safe, cheap, reliable and malleable" and provides a hope of treatments that are 'as gentle as possible' for patients.

Over the last 15 years Self, Thompson, and their small team at Newcastle have devised a procedure for coating/cloaking antibodies with an organic, photo-sensitive oil. This breaks down in the presence of UV-A light, meaning that the antibodies are only activated when they are exposed to this light.

Their recent pre-clinical trials, published in November, showed "very exciting" results: the cloaked antibody, combined with UV light delivered through a dental light probe, completely eradicated tumours in 5/6 cases and dramatically reduced the size of the tumours in the remaining subjects.

They are "very, very excited", and with good reason: this is potentially groundbreaking (and life-saving) work.

It would mean that future cancer patients would be able to receive injections of cloaked antibodies. These would pass through the rest of the body un-noticed, without causing harm, only to be triggered at the target area by UV light that could be specifically directed at the tumour using a probe. The antibodies would then attach to the tumour cells, and cause the patient's own immune system to fight the cancer.

This UV therapy could also be used following tumour-removal surgery. Surgeons could destroy any remaining cancer cells and increase the success of the operation simply by bathing the area in light before closing up.

Some limited antibody therapies are already in use, such as the much-publicised breast cancer drug, Herceptin. But these are expensive, and are not without side effects. This new cloaking technology has the potential to be combined with such existing treatments, increasing their effectiveness and specificity, and thus reducing side effects. The possibilities of 'cloaking' are numerous and exciting and this work with antibodies seems to be only the tip of a very large iceberg.

Subject to funding, clinical trials of the cloaked antibodies are due to start in 2008, treating patients with secondary skin cancers. If these trials are successful, it will be 2011 by the time the new technology can be used clinically. Even then, the therapy is limited to areas that are accessible by light probe, and any potential side effects are still to be discovered.

Despite the further scientific process ahead, and the time and money required Professor Self is confident that there will be a day when the "Department of Light Therapeutics" will be commonplace in hospitals around the world. "It's like driving from here to Scotland," he says during our interview in his Newcastle lab: "You know that Scotland is definitely there, and even if one road gets blocked, you will get there in the end".