Cancer Research UK Annual Review 2011/12

16 | Our scientists are finding the answers
Switching on the immune system
The immune system could be our
body’s most powerful weapon
against cancer – but often it needs
a helping hand. Our researchers
are developing ways to harness
it using ‘cancer vaccines’. Instead
of preventing the disease like
conventional vaccines, these
promising treatments are helping
trigger patients’ own immune systems
to target and destroy tumours.
Professor Alan Melcher has high
hopes for this approach. Based at
the Cancer Research UK Centre
at the University of Leeds, he talks
about his work and the complex
challenges he faces.
‘How do you develop a treatment
that stimulates a patient’s immune
system to target cancer without
causing harm elsewhere in the body
This is one of the main problems
my research aims to solve.
Usually, our immune systems aren’t
good at recognising cancer. But they
are extremely good at recognising
and responding to viruses. So we
have genetically engineered viruses
to carry molecules called antigens
that act as a detectable “fingerprint”
of the cancer cells.
The virus smuggles the antigens into
the body. Once injected, the immune
system wakes up, spots the virus and
attacks it. And as it does so, it helps
the immune system to recognise and
attack the tumour.
I’m optimistic about the
results so far, which could
see the cancer vaccine
we’re developing being used
alongside chemotherapy
and radiotherapy in five
to 10 years’ time.
Professor Alan Melcher
In the past, scientists have used only
a few antigens to stimulate the immune
response. What we’ve done is test
a whole library of antigens at once
to find out which ones work best.
We’ve found three that together
stimulate the immune system and
which could be used as the basis
of a vaccine to treat patients.
It’s a really targeted way of treating
cancers, which could help to reduce
side effects and benefit patients.’
Our researchers are pioneering new ways to tackle cancer and save more lives.