Scientists Crack Genetic Code of Two Common Cancers

Discovery could revolutionize cancer care, saving millions of lives

Carol Pearson | Washington 19 December 2009

It is being called a scientific breakthrough. British researchers say they have mapped the entire genetic code for two types of cancers -- small cell lung cancer and melanoma, the most deadly type of skin cancer.

All cancers are caused by changes in the DNA of cells. DNA carries the cells' genetic information. That information changes when cells gradually mutate from normal to abnormal and then to malignant over time.

Scientists say if they could only crack the genetic codes of different types of cancers, they could save millions of lives.

Blood tests could spot tumors early on. And treatment would be far more successful. Dr. Jeanny Aragon-Ching is an oncologist at the George Washington University Medical Center. She says this discovery is a step toward an era of personalized medicine. "That is the thrust now because, for instance, for different types of cancers, we have different types of drugs that target different domains or mutations," she said.

The more information doctors have about how cancer cells develop, the more precisely they can prescribe a treatment to target those particular cells.

British scientists found 30,000 mutations in melanoma, a type of skin cancer that accounts for 75 percent of skin cancer deaths. They also found 23,000 mutations in small cell lung cancer. But not all of these mutations cause cancer. "It is the role of physicians and scientists to find out which of those mutations are the driving force, or the driving mutation that actually led to the cancer," she said.

Eventually, scientists might be able to target pre-cancerous cells and prevent deadly tumors from forming. But that day is still far away. "As an oncologist, my goal would be to one day see that we can transform cancer into a chronic disease. Cure is probably too generous of a word the way I see it, but to convert it to something more like chronic disease that is treatable," she said.

Just like high blood pressure that can be controlled with medicine, cancer could be a disease without the suffering we associate with it. Medical scientists the world over are now working to catalogue all the genes that mutate in many types of cancer as part of an International Cancer Genome Consortium. In the United States they are studying cancers of the brain, ovaries and pancreas.

In addition to lung cancer and melanoma, scientists are examining the DNA of breast cancer, as well as cancers of the liver, the mouth and the stomach. "I think each step forward is a step toward our goal, our ultimate goal, which is to relieve the suffering from cancer," she said.

Scientists Discover New Species of Dinosaur

Paleontologists say the dinosaur they call Tawa, was about the size of a large dog, but with a longer tail.

Jessica Berman | Washington , from VOA

Scientists have discovered the fossilized remains of a new meat-eating dinosaur in a quarry in New Mexico. They say the finding sheds light on the evolution of these extinct creatures.

Paleontologists say the dinosaur they call Tawa, named for the Hopi Native American sun god, was about the size of a large dog, but with a longer tail, stood about 70 centimeters tall at the hips and was two meters long. The two-legged creature also had razor-sharp teeth for eating meat.

Scientists conducting an analysis of the newly-discovered, 215 million year old fossils and other early dinosaur remains say Tawa also had the characteristics of two other dinosaurs - the giant, plant-eating sauropod and the horned Triceratops.

They believe Tawa is the common ancestor of both dinosaur groups that migrated from Argentina to other parts of the world during the Pangea period, between 200 and 300 million years ago, when geologists say the Earth's continents were compressed into a single landmass.

The fossil discovery suggests that Tawa also used a land bridge from South America to make its way to North America, when Tyrannosaurus Rex began evolving into modern day birds, according to Sterling Nesbitt, a researcher at the University of Texas who led a team of excavators.

"Tawa is a little bit of a surprise because it's preserving these very early traits that we see in dinosaurs while living with animals that are much more closely related to bird," said Nesbitt.

According to Nesbitt, Tawa might answer important questions about a dinosaur called Herrerasaurus, which was discovered in Argentina in the 1960s.

Herrerasaurus has traits like T. Rex - including sharp claws and teeth - but lacks other characteristics of the carnivore. Scientists hope to determine whether Herrerasaurus is a direct descendant of Tawa or part of a different species of dinosaurs.

Nesbitt say the Hayden Quarry in northern New Mexico, where the ancient fossils were unearthed, is a rich bed containing other prehistoric bones and artifacts. He says he plans to continue digging at the site to learn more about Tawa.

"We want to know how it grew, how the features changed as the animal got older," he said. "We also want to look at the anatomical details."

A description of the new dinosaur species is reported this week in the journal Science.

Gene action may lead to diabetes prevention, cure

LOS ANGELES, Dec. 12 (Xinhua) -- A gene commonly studied by cancer researchers may provide answers to ways of fighting diabetes, a new study shows. The gene, known in the science world as PFKFB3, is a regulator for metabolism, which plays a vital role in the development of diabetes, according to the study appearing in the Dec. Journal of Biological Chemistry. The gene has been linked to the metabolic inflammation that leads to diabetes. Understanding how the gene works means scientists may be closer to finding ways to prevent or cure diabetes, said the study conducted by researchers at Texas AgriLife Research. "Because we understand the mechanism, or how the gene works, we believe a focus on nutrition will find the way to both prevent and reverse diabetes," said Dr. Chaodong Wu, AgriLife Research nutrition and food scientist who authored the paper with the University of Minnesota's Dr. Yuqing Hou. Wu said the research team will collaborate with nutritionists to identify what changes or supplements in a diet will activate the gene to prevent or stop the progression of diabetes. He believes nutritionists working with the biological chemists can help develop food consumption plans that either prevent people from developing metabolic inflammation or cause existing conditions to retreat. "First we will need to identify what effective compounds will trigger the gene to regulate metabolism," Wu said. "Then we need to determine what combinations within foods are more effective." Wu noted that while it is a major health concern in the U.S., obesity does not necessarily cause diabetes to develop; i.e., just because a person is overweight does not mean they have diabetes. Rather, "metabolic inflammation" causes or exacerbates the disease. Metabolic inflammation is different from classic inflammation because there is no infection, virus or bacteria present, though the symptoms appear similar.