With every step science takes toward reliable cancer treatment,
science also takes a step back: For every possible solution, there is
always a catch. For every group of patients that sees results from an
experimental treatment, many more see nothing.
However, a new concept—called personalized medicine—has
patients finding hope and researchers getting excited. Some of the most
important work on the subject is happening right here in Tucson, at the
University of Arizona.
Dr. Mark Pagel and his CAMEL (Contrast Agent Molecular Engineering
Lab) crew, armed with 10 colors of tape, are out to make the world a
better place, one MRI at a time. They are currently working on an
imaging method through which chemical agents indicate certain aspects
of a patient’s cancer that are then detected by MRI; that information
is then used to select and direct the course of treatment for that
patient.
Pagel says he first became interested in cancer research after his
father died of lung cancer in 1994.
“I’m really a chemist by training,” he says.
He began his career doing, among other things, MRI studies of the
effects of Celebrex (an anti-inflammatory drug) on breast cancer.
“But I wanted something more application-driven,” he says. In 2001,
he attended the “Imaging in 2020” conference and thought, “There’s just
got to be more we can do with (MRIs and other imaging techniques).” He
was inspired to combine his background in chemistry with the advances
being made in medical imaging to develop a way to detect the properties
of an individual’s unique tumor tissues.
That led Pagel to his current work and his interest in the concept
of personalized medicine. He explains that MRI machines are great for
looking at anatomy, but are also expensive (usually in the $1.5 million
to $3.5 million range). “Our goal is to use this big, expensive toy for
the most benefit,” says Pagel.
He hopes the techniques he is developing will help cancer patients
in several ways. The first is to predict which types of treatments will
work best on which patients.
“For example, we’re measuring the acidity (of the targeted area on
the patient),” he says—because some drugs don’t work as well when
the area is more acidic. “So right away, we know to say, ‘Don’t take
this drug; instead take this one.'”
The next goal is to monitor the delivery of that drug, possibly with
the help of nanotechnology. Finally, Pagel hopes that this imaging
technique will lead to earlier responses to treatment, ideally within
24 to 48 hours of initiating therapy.
Pagel’s work is in “pre-clinical” drug trials, meaning it is with
animals (usually mice) rather than actual patients. He says the biggest
hurdle his team is currently facing is Food and Drug Administration
approval. One issue: Even though the imaging agent used to detect and
expose the biological markers for each case is administered only once
or twice, the FDA treats it as if used chronically, making it more
difficult to get approval.
The labs he works in at the Arizona Cancer Center (near the
University Medical Center) are aging but temporary, says Pagel. He says
that there are plans in the works for a new biomedical imaging facility
nearby (and plans for a parking lot where the labs are now).
Inside is the constant, nondescript hum of machines working behind
the scenes. Foam padding has been attached to the walls to dampen the
whirring sounds, while metal doors corner off sections of the
warehouse-like room, hiding the mechanics at work. With its exposed
wires, cluttered corners and scarce seating, the lab does not look as
sterile as one might expect.
“You know, if you like everything professional-grade with logos on
it, and everything looks clean, clinical imaging is the place to be,”
he says. “But using duct tape and wires—that’s what we do
here.”
For instance, the tool he uses on mice during their MRI sessions is
basically just molded plastic attached to a yardstick, but the
researchers here perfected the technique. Pagel deals with the concepts
of his research in the same way he creates the parts and tools
necessary for his lab: He’s built what he needs out of pieces that
already existed and aims to bring them to their full potential.
Pagel came to the UA last year, and as an associate professor of
biomedical engineering and chemistry, he’s been especially excited
about the promise of interdisciplinary work.
“Part of the reason I came to the UA is because of the outstanding
collaborative research environment,” he says. His own work is a
collaboration between several organizations, including the Arizona
Cancer Center, the Institute for Collaborative BioResearch (BIO5) and
the biomedical engineering and chemistry departments at the UA.
Pagel’s hopes for the project are admirably high, but possible.
“We have a lot of patients from Phoenix who drive down to Tucson,”
he explains in an e-mail. He says he’d like to have a system in which
patients who drive from Phoenix can get the imaging tests in the
morning to predict which therapy will work for their specific case,
then have a chemotherapy test and another imaging test that night to
monitor the delivery of their chosen drug.
“Knowing that the therapy is working within 24 hours, instead of
three weeks, can relieve a lot of anxiety,” he continues. “Hopefully,
anyone who has driven from Phoenix to Tucson can appreciate this
advantage, or those who have waited weeks for test results will see the
advantage, too.”
This article appears in Aug 6-12, 2009.
