Light, chemistry, action – a new technique to target skin
Last updated on 5/13/2015 Print this page
11 April 2011
Targeted photodynamic therapy can completely eradicate some
models of cancer, according to the latest research by UK and Swiss
scientists, published in the current issue of the British
Journal of Cancer.
Cancer cell ©iStockphoto.com/Eraxion
The team – including researchers from the University of Hull and
ETH Zurich – linked light-sensitive molecules with antibodies that
target tumour blood vessels. When irradiated with light, the
molecules create particles known as reactive oxygen species, which
in high numbers cause irreparable damage to cells.
By ensuring the light-sensitive molecules were targeted at the
tumour blood vessels, the researchers could starve the tumour of
oxygen and nutrients and cause it to disappear completely, with no
re-growth during the following 100 days.
“There are already drugs in clinical use which target tumour
blood vessels, but these only inhibit growth rather than completely
kill the tumour,” explains Dr Ross Boyle, from Hull’s Department of
Chemistry, who designs and creates the light-sensitive molecules
used in the research.
“By using this form of targeted photodynamic therapy, we were
able to completely kill the tumour in our models. Though this is
still a long way from being used on patients, it does hold exciting
potential for the treatments of some of the most common skin
However, the tumour was only completely eradicated when ‘natural
killer cells’ – a key part of the immune system – were present.
When the production of these was blocked, the tumour reduced in
size, but did not disappear. The team believe further research is
needed to determine the exact role of the immune system in the
Targeting light-sensitive molecules to a tumour site ensures
that the treatment should be more effective even at smaller doses,
improving outcomes and reducing potential side effects to patients.
The technique could potentially replace more invasive forms of
treatment such as surgery and radiotherapy.
Dr Boyle and his colleagues are now applying for further funding
to move the research closer to clinical trials.