Scientists develop crystal ball for personalized cancer treatment

Feb 02, 2009
Top, a PET scan reveals a mouse with two tumors; the left tumor is gemcitabine-sensitive and the right tumor is gemcitabine-resistant. Below, the UCLA probe is absorbed only by the cells of the (left) tumor that responds to gemcitabine.

For many cancer patients, chemotherapy can be worse than cancer itself. A patient may respond to one drug but not another -- or the tumor may mutate and stop responding to the drug -- resulting in months of wasted time, ineffective treatment and toxic side effects.

Now UCLA scientists have tested a non-invasive approach that may one day allow doctors to evaluate a tumor's response to a drug before prescribing therapy, enabling physicians to quickly pinpoint the most effective treatment and personalize it to the patient's unique biochemistry. The Proceedings of the National Academy of Sciences publishes the UCLA findings in its Feb. 2 advance online edition.

"For the first time, we can watch a chemotherapy drug working inside the living body in real time," explained Dr. Caius Radu, a researcher at the Crump Institute for Molecular Imaging and assistant professor of molecular and medical pharmacology at the David Geffen School of Medicine at UCLA. "We plan to test this method in healthy volunteers within the year to determine whether we can replicate our current results in humans."

In an earlier study, Radu and his colleagues created a small probe by slightly altering the molecular structure of gemcitabine, one of the most commonly used chemotherapy drugs. They labeled the probe with a special tag that enabled them to watch its movement throughout the body during imaging.

In this study, the UCLA team injected the probe into mice that had developed leukemia and lymphoma tumors. After an hour, the researchers imaged the animals' bodies with positron emission tomography (PET), a non-invasive scan often used on cancer patients to identify whether a tumor has spread from its original site or returned after remission.

"The PET scanner operates like a molecular camera, enabling us to watch biological processes in living animals and people," said Radu, who is also a member of the Jonsson Comprehensive Cancer Center at UCLA. "Because we tag the probe with positron-emitting particles, the cells that absorb it glow brighter under the PET scan."

"The PET scan offers a preview for how the tumor will react to a specific therapy," added first author Rachel Laing, a UCLA graduate researcher in molecular and medical pharmacology. "We believe that the tumor cells that absorb the probe will also take up the drug. If the cells do not absorb the probe, it suggests that the tumor might respond better to another medication."

The UCLA researchers plan to expand the scope of their research by examining whether the probe can predict cellular response to several other widely used chemotherapy drugs. Their goal is to determine whether the probe can provide a diagnostic test of clinical value.

"The beauty of this approach is that it is completely non-invasive and without side effects," said Radu. "If we are successful in transporting this test to a clinical setting, patients will be able to go home immediately and resume their daily activities."

If testing in healthy subjects proves safe and effective, UCLA researchers will begin recruiting volunteers for a larger clinical study of the probe in cancer patients.

Source: University of California - Los Angeles

Explore further: DNA alternative to Pap smear sparks medical debate (Update)

add to favorites email to friend print save as pdf

Related Stories

New high-tech glasses detect cancer cells during surgery

Mar 10, 2014

A team of scientists at Washington University School of Medicine in St. Louis (WUSTL) and the University of Arizona (UA) in Tucson led by Samuel Achilefu have created a pair of high-tech glasses that help ...

A nano-sized sponge made of electrons

Nov 12, 2013

A new chapter has been opened in our understanding of the chemical activity of nanoparticles says a team of international scientists. Using the X-ray beams of the European Synchrotron ESRF they showed that ...

Nanodiamonds: A cancer patient's best friend?

Oct 23, 2013

Diamonds are sometimes considered as a girl's best friend. Now, this expression is about to have a new meaning. Indeed, nanometric scale diamond particles could offer a new way to detect cancer far earlier ...

Recommended for you

DNA alternative to Pap smear sparks medical debate (Update)

16 hours ago

A high-tech screening tool for cervical cancer is facing pushback from more than a dozen American patient groups, who warn that the genetic test could displace a simpler, cheaper and more established mainstay of women's health: ...

User comments : 0

More news stories

ESO image: A study in scarlet

This new image from ESO's La Silla Observatory in Chile reveals a cloud of hydrogen called Gum 41. In the middle of this little-known nebula, brilliant hot young stars are giving off energetic radiation that ...

First direct observations of excitons in motion achieved

A quasiparticle called an exciton—responsible for the transfer of energy within devices such as solar cells, LEDs, and semiconductor circuits—has been understood theoretically for decades. But exciton movement within ...

Patent talk: Google sharpens contact lens vision

(Phys.org) —A report from Patent Bolt brings us one step closer to what Google may have in mind in developing smart contact lenses. According to the discussion Google is interested in the concept of contact ...

Warm US West, cold East: A 4,000-year pattern

Last winter's curvy jet stream pattern brought mild temperatures to western North America and harsh cold to the East. A University of Utah-led study shows that pattern became more pronounced 4,000 years ago, ...