Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A crystal ball for brain cancer?

03.08.2009
New UCLA method predicts which brain tumors will respond to drug

UCLA researchers have uncovered a new way to scan brain tumors and predict which ones will be shrunk by the drug Avastin -- before the patient ever starts treatment. By linking high water movement in tumors to positive drug response, the UCLA team predicted with 70 percent accuracy which patients' tumors were the least likely to grow six months after therapy.

Bronnie McNabb, 57, considers himself lucky. When his aggressive brain cancer returned after chemotherapy and radiation, his UCLA doctor prescribed the off-label use of Avastin, a drug shown to quell cancers in the breast, colon and lung.

One month later, McNabb's tumors had shrunk by 95 percent. Subsequent brain scans show no trace of his cancer at all. The former marathon runner, ordained minister and father of two says he hasn't felt this good since his diagnosis last winter.

In welcome news for patients like McNabb, the U.S. Food and Drug Administration approved the use of Avastin last month for the treatment of brain cancer. The powerful drug shrinks tumors by choking off their blood supply. Half of patients don't respond to the therapy, though, exposing them to unnecessary side effects and medication costing up to $10,000 per month.

Now UCLA scientists have uncovered a new way to image tumors and forecast which patients, like McNabb, are most likely to benefit from Avastin before starting a single dose of treatment. The findings are published in this month's issue of the journal Radiology.

"Avastin is an expensive drug, yet only 50 percent of patients with recurring brain cancers respond to it," said lead author Dr. Whitney Pope, assistant professor of radiological sciences at the David Geffen School of Medicine at UCLA. "Until now, there has been no good way to identify these patients in advance. Our work is the first to suggest that we can predict which tumors will respond before the patient ever starts therapy."

Pope and his colleagues focused on glioblastoma, the most common and deadly form of adult brain tumor, striking 12,000 Americans a year. Despite therapy with surgery, radiation and chemotherapy, the average glioblastoma patient lives only 12 to 15 months after diagnosis.

Survival rates drop even lower if the tumor returns. Conventional therapies produce little benefit; only 8 to 15 percent of patients survive without tumor growth six months after treatment.

The UCLA team studied 82 patients who had undergone surgery and radiation therapy to remove glioblastoma. Half of the patients received infusions of Avastin every two weeks. All underwent monthly brain scans by magnetic resonance imaging (MRI) to monitor change.

The researchers analyzed the MRI scans of the patients whose tumors returned. Explaining what the team saw requires an understanding of how the tumor creates an independent blood supply.

Cancer cells secrete a growth factor called VEGF that spurs the growth of new blood vessels to supply the tumor with oxygen and nutrients. Avastin blocks VEGF, essentially starving the tumor to death.

This process launches a chain of events that is detectable by MRI. Oxygen-starved cells produce more VEGF, which causes blood vessels to leak fluids into the tumor and surrounding tissue. This results in swelling, which boosts water's ability to move freely in the tumor and brain tissue. As cells disintegrate, they no longer pose a physical barrier to water movement.

"We theorized that tumors with more water motion would also have higher VEGF levels," explained Pope. "Because Avastin targets VEGF, it made sense that the drug would work better in tumors with high levels of the growth factor."

By measuring the amount of water motion within the tumor, the researchers were able to predict with 70 percent accuracy which patients' tumors would progress within six months and which would not. They detected greater water movement in the tumors of those persons who later responded best to Avastin.

"When we realized that high levels of VEGF are linked to greater cell death and increased water movement, we were able to predict the patients' response to Avastin before they began treatment," explained Pope. "We were correct 70 percent of the time. Previously, identifying which patients would respond was like flipping a coin. This is a huge improvement."

The research finding presents clear clinical benefits to the patient, says Pope. "Knowing this information ahead of time will help doctors personalize therapy for each patient and decrease exposure to side effects," he noted.

Pope and his colleagues plan to confirm their findings in a larger study. The team will also test the new method's ability to identify responsive patients prior to surgical removal of their tumor.

Pope's coauthors included Dr. Timothy Cloughesy, Hyun Kim, Jing Huo, Jeffry Alger, Matthew Brown, David Gjerson, Dr. Victor Sai, Jonathan Young, Leena Tekchandani, Dr. Paul Mischel, Dr. Albert Lai, Dr. Phioanh Nghiemphu, Dr. Syed Rahmanuddin and Dr. Jonathan Goldin. All authors are affiliated with UCLA, which funded the research.

Pope and Cloughesy are consultants for Genentech, which manufactures Avastin, and are collaborating with the company on several research studies.

Elaine Schmidt | EurekAlert!
Further information:
http://www.ucla.edu

Further reports about: Avastin MRI MRI scan UCLA VEGF blood supply blood vessel brain cancer brain scans brain tumor

More articles from Medical Engineering:

nachricht Rutgers researchers develop automated robotic device for faster blood testing
14.06.2018 | Rutgers University

nachricht Speech comprehension with a cochlear implant
04.06.2018 | Universität zu Lübeck

All articles from Medical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Carbon nanotube optics provide optical-based quantum cryptography and quantum computing

19.06.2018 | Physics and Astronomy

How to track and trace a protein: Nanosensors monitor intracellular deliveries

19.06.2018 | Life Sciences

New material for splitting water

19.06.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>