Knocking out cancer
New delivery method may enhance treatment
BY LIZ KATYNSKI
Winnipeg Health Region
Wave, November / December 2012
Dr. Thomas Klonisch is working on a
research project that could one day lead
to a cure for brain cancer, one of the most
difficult of all tumours to treat.
In fact, the project, led by Klonisch and
Drs. Jörg Stetefeld and Jerry Krcek, has
already generated positive results in early in-vitro
and animal testing and could be ready
for clinical trials within the next few years.
The research centres on the development
of an efficient mechanism to deliver
chemotherapy to destroy brain cancer cells.
Krcek, a neurosurgeon at Health Sciences
Centre, identifies three ways currently used
to treat brain cancer - surgery, radiotherapy
and chemotherapy. But the success of these
treatments is limited, and for certain types of
brain cancer there is no cure.
Klonisch says he, Krcek and Stetefeld hope
to change that, with the help of a family of
proteins that can form tubes. One of these
proteins is found in a bacterium that grows
deep down on the sea floor.
An associate professor of biochemistry
at the University of Manitoba, Stetefeld
has discovered that these proteins, called
"right-handed coiled-coil proteins," lend
themselves to forming "tubes" that can be
used to convey chemotherapy using noble
metals like platinum. "These coiled protein
aggregates create little nano-tubes," says
Klonisch, Head of the Department of Human
Anatomy and Cell Science at the University
of Manitoba's Faculty of Medicine. "And
we use those nano-tubes as carriers for
chemotherapeutics," he says.
The proteins are a story all on their own.
"What is really fascinating about this is
the tubes come from a bacterium, and the
bacterium grows near volcano-like openings
at the bottom of the ocean, more than 3,000
metres below the surface. This is a harsh
environment these tubes are exposed to. They
are very resilient," he says, explaining why
they can handle chemotherapeutic drugs.
Klonisch and his colleagues have found
different ways to make platinum used in
chemotherapy treatments interact with the
nano-tubes and be released over time. So far,
the team has had success in treating brain
cancer cells in the lab. "Under the right
conditions, these coiled protein nano-tubes
with platinum are highly effective in killing
tumour cells," Klonisch says.
The next phase of the project involves
more testing using human brain cancer cells
in the lab to confirm the findings. Now that
Klonisch knows that the platinum-laden
proteins can kill cancer cells under certain
conditions, the challenge going forward
will be to determine whether the delivery
system can effectively penetrate the blood-brain
barrier. "The work is all ongoing,
and the good thing is it is all ongoing here
with local experts," says Klonisch. For
example, the team is collaborating with
experts in neurosurgery, neuropathology,
pharmacology, chemistry and anatomy to
develop ideas about how to get the platinum-loaded
protein nano-tubes into the brain.
Other experts will be consulted once the
team firms up its evidence, Klonisch says.
Back to "Research for better health"
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Read the November / December 2012 issue of Wave