College of Science Magazine
Issue No.1 Fall 2005
Chemical and biological researcher s team up to
develop ne w light-activated cancer therapies
C
all it coincidence. Call it destiny.
Call it good fortune. Whatever it
was, when two young scientists
met at new faculty orientation at Virginia
Tech in 1992, it was the start of something
great.
In the 13 years since then, Karen Brewer, professor of
chemistry, and Brenda Winkel, professor of biology, have
led research teams that have developed new and potentially
revolutionary ways of treating cancer in humans.
A plant biologist and inorganic chemist working side-byside? It seemed an unlikely union, but when a graduate
student in chemistry that same year expressed an interest
in taking a biological focus in his research, the deal was
sealed.
Light absorbing unit
Active sites
their work focused on the other drawback with Cisplatin
– that tumors can become resistant to the drug. And that’s
where the beauty of having a biologist and chemist working
closely together really started to show.
While Winkel’s team worked on DNA interactions, Brewer’s
team was busy modifying the chemical structures of the
drug.
Employing basic techniques that are routinely used in
Winkel’s lab, doctoral student Matt Milkevitch was able
to develop an assay for DNA binding activity that has now
become standardized in other chemical biology labs. The
team was eventually able to change the shape and basic
properties of the drug molecule, thus making it unrecognizable to the tumor.
Metal-based systems for delivering pharmaceuticals are
a popular area of research. One reason is that metals are
constantly interacting with their environments, thus their
properties and reactivity can easily be changed. Metals are
also advantageous because they can be made into highly
colored dyes and by doing so are more easily detected.
Using colored systems also helps with the team’s research
into light-activated therapy.
Bridge units
Light across
Disciplines
Shedding
Ne w Mo l e c u l a r St r u c t u re s
The research team started by looking at ways to overcome
some of the inherent drawbacks in the widely used cancer
drug Cisplatin. One such drawback is that the drug does
not dissolve well in water. This means it must be crushed
and administered in suspension form, which can cause
significant kidney damage.
So the first thing the research team did was develop a
system that would dissolve in water. Once they did that,
College of Science Magazine
Issue No.1 Fall 2005
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