UV light improving chances of fighting cancer

Scientists at Newcastle University have developed a cancer fighting technology which uses UV light to activate antibodies which very specifically attack tumours.

Therapeutic antibodies have long been recognised as having excellent potential but getting them to efficiently target tumour cells has proved to be very difficult.

Now, Professor Colin Self and Dr Stephen Thompson from Newcastle University have developed a procedure to cloak antibodies which can then be activated by UV-A light and so can be targeted to a specific area of the body just by shining a probe at the relevant part.

This procedure maximizes the destruction of the tumour while minimising damage to healthy tissue.

Professor Self says, “I would describe this development as the equivalent of ultra-specific magic bullets. This could mean that a patient coming in for treatment of bladder cancer would receive an injection of the cloaked antibodies. She would sit in the waiting room for an hour and then come back in for treatment by light. Just a few minutes of the light therapy directed at the region of the tumour would activate the T-cells causing her body’s own immune system to attack the tumour.“

The details are contained in two papers* published online today in the journal ChemMedChem.

The Newcastle University researchers demonstrate in the first paper the procedure of coating the surface of a protein, such as an antibody, with an organic oil which is photocleavable, a process called “cloaking”. This prevents the antibody reacting within the body unless it is illuminated.

When UV-A light is shone onto the cloaked antibody it is activated. The activated antibody binds to T-cells, the body’s own defence system, triggering the T-cells to target the surrounding tissue.

In the second paper, they demonstrate that when the cloaked antibodies are activated by light near a tumour, the tumour is killed. This work means that antibodies can be targeted to kill cancer tumours with much greater specificity giving fewer side effects.

These cloaked antibodies can be used alone, or in conjunction with the many antibodies already produced against a wide variety of cancers as bispecific complexes. These complexes are formed from two antibodies, one antibody binds to a tumour marker, the other with a T-cell. The T-cell binding end remains inactive until re-activated by light. This means when the bispecific antibody binds to healthy tissues away from light, it cannot activate T-cells, resulting in far fewer side effects.

Professor Self says, “This opens up so many possible applications for example, for patients who are undergoing surgery for prostate cancer. After the surgeon has removed the bulk of a tumour, the patient could then be injected with bispecific antibodies and a light shone at the affected area which would target the patient’s own immune system to the tumour site.”

“This is therefore a very specific treatment and while our work indicates that sunlight doesn’t activate these antibodies, patients may have to be advised to avoid direct sunlight for a short period after treatment.”

Source: Newcastle University

Related stories:

New targeted approach to light-activated cancer drugs
Combining light-activated cancer drugs with tumour-seeking antibodies could provide a more effective way of treating many cancers, according to new research published in advance online in the International Journal of Cancer.
Study sees need for standardized evaluation of antibody response to HIV-1
U.S. Military HIV Research Program (USMHRP) researcher Victoria R. Polonis, Ph.D., and colleagues released findings on a study of cross-clade neutralization patterns among HIV-1 strains from six major clades in the 5 Jun 2008 issue of Virology.
Ricin's deadly action revealed by glowing probes
A new chemical probe can rapidly detect ricin, a deadly poison with no known antidote that is feared to be a potential weapon for terrorists and cannot quickly be identified with currently available tests.
HIV conquers immune system faster than previously realized
New research into the earliest events occurring immediately upon infection with HIV-I shows that the virus deals a stunning blow to the immune system earlier than was previously understood. According to scientists at Duke University Medical Center, this suggests the window of opportunity for successful intervention may be only a matter of days – not weeks – after transmission, as researchers had previously believed.
New Device Shines Light on Disease-Causing Molecules
If a doctor could identify a single molecule indicating the presence of a disease before the disease has a chance to harm the patient, the practice of medicine and the health of patients would be greatly improved. That’s the potential of a new device being developed by a University of Missouri engineer that is designed to aid in the diagnosis of disease. This technique, which is based on light detection, is sensitive enough to potentially identify a single disease molecule.
Finding suggests novel ways to boost vaccination or natural defenses
Our bodies rely on the production of potent, or 'high affinity', antibodies to fight infection. The process is very complex, yet Sydney scientists have discovered that it hinges on a single molecule, a growth factor, without which it cannot function.
Finding that could shed light on 'golden staph,' candida and allergies
Recent scientific findings explain why patients with a rare immunodeficiency disorder are unusually susceptible to certain common infections. By revealing the exact molecular mechanisms involved, they also give us clues as to why some 'healthy' people are more prone to these infections than others, and suggest potential treatments.
Worm-like marine animal providing
The marine invertebrate amphioxus offers baseline information for genetic roots of vertebrate innovation such as the adaptive immune system
Research on the genome of a marine creature led by scientists at Scripps Institution of Oceanography at UC San Diego is shedding new light on a key area of the tree of life.

News discussion:

Medicine & Health news