Industry spotlight health care
Finding cancer
A blood test developed
at Baylor Research
Institute can identify
cancer-related components before tumors start
to grow. Dr. Ajay Goel,
director of Epigenetics
and Cancer Prevention,
helped develop the test.
38
Ajay Goel, Ph.D., director of Epigenetics and Cancer Prevention at Baylor Research Institute, is not – as
he says – your typical scientist. “Most Ph.D. scientists
are expected to do very basic research. However, I have
been very fortunate to work with some of the very best
physicians, and we develop these things together. Over
the years, I have become a translational scientist, using
my work to change clinical science. This is exciting for
a basic scientist like me.”
The test that has put Goel on the map – and North
Texas front and center in the world of cancer research
– is a new blood test developed in the Gastrointestinal
Cancer Research Lab at Baylor Research Institute that
shows very promising results for finding cancer-related components in the blood before a tumor develops
in the colon. This small, simple blood-based test examines the levels of a single microRNA (MiRNA) – a
small RNA molecule that can be readily identified in
a wide variety of bodily fluids, including blood – and
determines a patient’s risks for developing polyps that
may lead to colon cancer.
Goel credits Dr. C. Richard Boland, an investigator with Baylor Research Institute and chief of gastroenterology at Baylor University Medical Center, for
helping to develop the test. “I was fortunate enough to
work with Dr. Boland. We developed this together.”
“We have been working for several years on the
epigenetics of colorectal cancer, which is the study of
changes in gene expression not caused by a change in
the DNA sequence. Dr. Goel has been at the forefront
of work on microRNAs,” Boland explained. “A test like
this could make it clear how important it would be to
go ahead with the colonoscopic exam, or may permit
the person to wait another year.”
The current screening method, a colonoscopy, is
currently the best standard for early detection of colon
cancer. However, low compliance and people’s anatomy often make it hard for even the best physicians to
catch all polyps in a person’s colon. Using colonoscopy
alone as a screening tool is risky, Goel notes. “It is invasive, and therefore, it has poor compliance, even in the
U.S. The cost is high, and it involves human bias. With
a blood test, there is no bias.”
By contrast, the test Goel is developing is highly
accurate and very sensitive. In this seminal study, the
investigators studied several hundred patients with
colorectal polyps and cancers and reported that measuring levels of miR-21 in the blood can accurately
identify up to 92 percent of patients with colorectal
cancer. Even more importantly, the test can accurately
identify up to 82 percent of patients with advanced colonic polyps, which present the highest risk for developing into colorectal cancers several years later in life.
A little bit like predicting the future, isn’t it? While
Goel shrugs off any crystal ball references, he does
point out that the test not only has accuracy, it’s also
inexpensive and easy for others to replicate. Previous
tests developed by others were gene- or DNA-based
tests, which include long sequences and large samples
to review. Although some of these tests came close,
Goel says they were ultimately not the answer.
“You cannot collect that kind of sample, because
the signatures are not very stable,” Goel said. “You cannot effectively use DNA or RNA. MiRNA, on the other
hand, is very small, which makes it very stable. You can
draw blood and analyze it years later – in fresh tissue
or in archival tissues. It can be stable on trips across the
oceans. From a biomarker or practical standpoint, that
is always a huge concern.”
Goel’s test is the first early diagnostic test to focus on miRNA in the blood, which is extolled for its
virtues including its non-invasiveness, low cost and
ability for many people to replicate even without expensive equipment.
“You don’t have to open up anyone, you don’t have
to do surgery. And, if you can find them at the polyp
stage, you can remove polyps,” he explains. Goel also
stresses that this test does not replace a colonoscopy
for those with potential for colon cancer – it’s meant as
a screening tool to keep those who do not have polyps
from needing the test as a routine screen.
Goel’s test is one of more than 800 active research
protocols being conducted today at the Baylor Research Institute, the research component of the Baylor
Health Care System, which works to bring innovative
treatments from the laboratory workbench to the patient’s bedside, making a real difference for patients
in North Texas and around the world. The institute’s
250 research investigators are doing important work in
areas ranging from human immunology and orphan
metabolic diseases to diabetes, cardio-vascular disease
and many other unmet medical needs.
“No two cancers are alike,” he noted. “Even with people with the same disease – no two cancers are similar.
Heterogeneity is why you need more than one marker.”