Scientists Develop 'Crystal Ball' For Personalized Cancer Treatment

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.

The study was funded by The Dana Foundation, National Cancer Institute, Department of Energy and Howard Hughes Medical Institute. Radu and Laing's coauthors included Martin Walter, Dean Campbell, Harvey Herschman, Nagichettiar Satyamurthy, Michael Phelps, Johannes Czernin and Owen Witte, all of UCLA.

Plums Poised To Give Blueberries Run For The Money

There’s an emerging star in the super-food world. Plums are rolling down the food fashion runway sporting newly discovered high levels of healthy nutrients, say scientists at Texas AgriLife Research.Plainly, “blueberries have some stiff competition,” said Dr. Luis Cisneros, AgriLife Research food scientist."Stone fruits are super fruits with plums as emerging stars."

Far from fruit snobbery, the plum is being ushered in after Cisneros and Dr. David Byrne, AgriLife Research plant breeder, judged more than 100 varieties of plums, peaches and nectarines and found them to match or exceed the much-touted blueberries in antioxidants and phytonutrients associated with disease prevention.

The duo acknowledge that blueberries remain a good nutritional choice. But Byrne said their findings are plum good news, especially in tight economic times, because one relatively inexpensive plum contains about the same amount of antioxidants as a handful of more expensive blueberries.

“People tend to eat just a few blueberries at a time – a few on the cereal or as an ingredient mixed with lots of sugar,” Cisneros said. “But people will eat a whole plum at once and get the full benefit.”

Discovery of the plum’s benefits – along with that of fellow stone fruits, the peach and the nectarine – came after the researchers measured at least five brands of blueberries on the market. Against those numbers, the team measured the content of more than 100 different types of plums, nectarines and peaches.

The first comparison was for antioxidants, molecules that sweep through a body looking for free radicals to knock out. Free radicals are atoms or molecules that lurk where diseases like cancer and heart disease are found.

"If the radicals aren’t taken care of,” Cisneros said, “they will cause the problems that lead to disease.”

But the scientists didn’t stop at knowing that plums and peaches were flexing their antioxidant muscles.

“Knowing that we had all these varieties with high levels of antioxidants, then the possibility of preventing these diseases would also be high with their consumption, so we went to the next step – how these compounds could actually inhibit chronic diseases,” Cisneros said.

The team examined the full content of plums and peaches, then tested the effect of the compounds they found on breast cancer cells and cholesterol in the lab.

“We screened the varieties again with the biological assays,” Cisneros said. “And that had never been done before, because it is expensive and a lot of work. But that investment is small in terms of the information we got, and how it can be used now for breeding efforts to produce even better fruit.”

Byrne noted, for example, that one benefit the team found was that the phytonutrients in plums inhibited in vitro breast cancer growth without adversely affecting normal cell growth.

He said this type of research needs further study but is an indication that breeders ultimately will be able to produce new crop varieties with the best ratio of various phytochemicals to have an impact on disease prevention and inhibition. And these fruits will be available as fresh produce as well as in extracts for dietary supplements.

"Future work with stone fruits will focus on cardiovascular and cancer using animal models and identification of specific compounds that exert the properties," Cisneros added.

Bottom line from the researchers: “We suggest that consumers take seriously the recommendation to eat at least five servings of fruits and vegetables – or even more – every day and to make sure that plums are part of that,” Byrne said.

Funding comes from the Vegetable and Fruit Improvement Center at Texas A&M University and the California Tree Fruit Agreement.

Surgeons Use Microwave Technology To Destroy Tumors

A new minimally-invasive option for treating liver tumors, called microwave ablation, is now available at UC San Diego Medical Center and Moores UCSD Cancer Center, the only hospitals in the region to offer this technology to patients.“A liver tumor can be removed in many ways,” said Marquis Hart, MD, transplant surgeon at UC San Diego Medical Center. “Now, patients at UC San Diego have a new option called ‘microwave ablation.’ Simply put, we zap and destroy liver tumors with heat derived from microwave energy. This is an important alternative, especially since the majority of liver cancers cannot be partially removed and not all patients are transplant candidates.”

Liver cancer is on the rise in the United States, linked closely with the epidemic of hepatitis and other conditions causing cirrhosis, a degenerative disease of the liver. Current treatment options for liver cancer include transplantation, partial surgical removal of the liver, chemotherapy, radiation, or ablation—the destruction of abnormal tissue with heat from radiofrequency waves, high frequency ultrasound, freezing, or alcohol injection. Now, microwave technology, offered by Covidien, removes the tumor with intense heat.

To perform the procedure, Hart accesses the tumor through the skin, or through a small laparoscopic port or open incision. With ultrasound guidance or a computed tomography (CT) scan, the tumor is located and then pierced with a thin antenna which emits microwaves. This energy spins the water molecules in the tumor producing friction which causes heat. Temperatures above 60 degrees Celsius (140 degrees Fahrenheit) cause cellular death, usually within 10 minutes.

“Microwave ablation causes the tumor to be quickly and precisely removed. If necessary, multiple tumors can be treated at the same time,” said Hart. “This method appears to be more efficient than other ablation techniques which translates to better tumor destruction and less time for the patient under general anesthesia.”

In addition to liver disease, microwave ablation has promising potential in the treatment of lung, kidney, and bone cancer.

“The incidence of liver cancer in the United States has more than doubled in the last 20 years,” said Hart. “Conditions that cause chronic liver damage increase the risk of liver cancer. Fortunately the treatment options at UC San Diego Medical Center and Moores UCSD Cancer Center are numerous. No where else in the region will you find a multidisciplinary team of surgeons, hepatologists, radiologists, and oncologists offering the latest in cancer care. With a team dedicated specifically to the liver, our patients receive cutting–edge care from a diverse team of experts.”

According to the National Cancer Institute, primary liver and bile duct cancers are the fifth most common cause of cancer death in men and the ninth most common cause of cancer death in women. More than 90 percent of all cases occur in men and women age 45 or older. Liver cancer is closely associated with hepatitis virus infections. The incidence and mortality rates for these cancers have increased in all races and both sexes in the past two decades.