Blood Pressure Compound May Benefit Brain Tumor Patients


ScienceDaily (Feb. 19, 2009) — A widely used blood pressure medication may be
the key to preventing brain function loss common after radiation treatment,
according to a newly published study by researchers at Wake Forest University
Baptist Medical Center. The findings offer the hope of an improved quality of
life for cancer patients.

Using a rat model, the study drew on a hypothesis from previous studies that a
compound similar to the anti-hypertensive drug losartan can prevent the
cognition loss that has been closely-associated with radiation therapy for brain
tumor treatment.

The findings, recently published in the International Journal of Radiation
Oncology, Biology, Physics, appear to validate the hypothesis in rats and
researchers are optimistic that the same theory could easily be applied in a
human clinical trial setting because the drug used has a long-established safety
profile in patients who have taken it to treat high blood pressure.

"We need to kill cancer cells but also prevent or reduce treatment-related side
effects," said Mike E. Robbins, Ph.D., a professor in the department of
radiation oncology at the Brain Tumor Center of Excellence, part of Wake Forest
University School of Medicine. "One very interesting feature of this compound is
that it has never shown any pro-tumor effects. If anything, it appears to have
anti-tumor properties. We're very close to having a compound that will protect
the normal brain from cognitive injury as a result20of radiation and, at the
same time, we may very well increase the likelihood of one day curing brain
cancer patients of their tumors."

Researchers have theorized from previous studies that radiation may lead to the
overproduction of angiotensin II (Ang II), a peptide that has been associated
with decline of brain function. By blocking the binding of Ang II to the Ang
type I receptor in patients receiving radiation, researchers hypothesized that
they could prevent or hinder cognitive decline. Anti-hypertensive drugs, such as
losartan, have been effective in preventing or minimizing radiation-induced
injury in the lungs and kidneys, Robbins said, so testing them in the brain was
an obvious next step.

The study involved three groups of 80 rats. Each group was divided in half to
either receive radiation or no treatment. Then, each of those halves was divided
into two more groups: one that received L-158,809, the compound similar to
losartan, in its drinking water, and one group that received plain drinking
water. The rats that received the drug received it before, during and for
different time intervals – 14, 28 or 54 weeks – post-radiation.

In addition, a small group of rats continued to receive the drug for only five
weeks after radiation.

Researchers found that administering L-158,809 before, during and for as little
as five weeks after radiation either prevents or lessens the severity of
radiation-induced cognitive impairment.

"The extent of cognitive impairment experienced by patients who undergo radiati
on therapy varies in terms of how it is recognized," Robbins said. "Sometimes
the patient realizes that their short-term memory is fading or that they've lost
the ability to multi-task. Instead of waking up in the morning and having a
clear idea of what needs to get done that day, patients finds themselves having
to write things down. They just can't keep thoughts in their brain. Sometimes
it's a friend or partner that realizes the impairment, but once it is noticed,
it is not going to improve. Cognitive decline resulting from radiation is not
stable. It is a chronic, progressive condition."

An estimated 170,000 patients undergo radiation therapy annually to treat
primary or metastatic brain tumors. At least 50 percent of adult patients who
undergo the treatment and live six months or more post-radiation experience some
level of cognitive decline. In children, the effect is even greater, Robbins
said. "All will have some form of cognitive impairment if they are long-term
survivors and, thankfully, with today's technology, most children will survive
long-term.

"This study provides hope that we may be able to take a drug that has been
prescribed to millions of individuals with essentially very little morbidity and
give it to cancer patients and stop them from experiencing cognitive impairment
as a result of brain radiation. These drugs are routinely prescribed for the
treatment of hypertension, are well-tolerated and exhibit anti-tumor effects,"
Robbins said. "They appear to be ideal for future clinical trials because they
of
fer the promise of improving the quality of life for brain tumor patients."

Co-researchers on the study, funded by the National Cancer Institute, were
Valerie Payne, B.S., Ellen Tommasi, B.S., Debra I. Diz, Ph.D, Fang-Chi Hsu,
Ph.D., William R. Brown, Ph.D., Kenneth T. Wheeler, Ph.D., John Olson, M.S. and
Weiling Zhao, Ph.D., all of Wake Forest University School of Medicine.

Adapted from materials provided by Wake Forest University Baptist Medical
Center.




GBYAY Anne McGinnis Breen
See my ponytail bouncing and my smiley face winking at you? &;>)

My new personal bt blog with my list of 28 questions to ask your doctor about
brain tumor treatments is http://gbyay.blogspot.com
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"Hope has two daughters--anger and courage: anger at the way things are and the
courage to work to make things other than they are." -- Saint Augustine
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Keep you faith, cherish your reason, treasure your mind and hold to your own
good purpose...be not afraid!


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