A German biotech company has announced positive results from a genetically engineered herpes virus that is designed to kill cancer cells. It not only kills the cancer cells but leaves healthy tissue unharmed. Results from clinical trials has showed promise.

Being injected with a virus might seem strange but researchers believe that viruses could one day become a valuable addition to conventional cancer treatments.

The results have shown in animal testing and limited human testing the ability to kill colorectal and liver cancer cells.

Researchers have found that when cells become cancerous, they become 100 times more likely to genetically mutate than non-cancerous cells. This explains why tumor cells have so many mutations. Good news on the research front. But bad news on the treatment front -- because therapies that target a certain gene may be largely ineffective in controlling cancer.

"This is very bad news, because it means that cancer cells in a tumor will have mutations that protect them from therapeutics," says lead researcher Dr. Lawrence Loeb, professor of pathology and biochemistry at the University of Washington School of Medicine in Seattle, who presented his findings February 18 at the meeting of the American Association for the Advancement of Science in San Francisco.

Loeb says chemotherapy drugs target specific oncogenes -- genes that affect the malignancy of a cell -- but if cancer cells are mutator cells, then a single tumor may have cells with all sorts of oncogenes. And while chemotherapy may kill some cancerous cells, millions of others will live on.

It's not all bad news, though, says Loeb who believes this research may help doctors determine the stage and malignancy of tumors by testing the number of mutations. It may also help researchers understand what makes a cancer cell a mutator and how to slow the rate of mutation.

"The idea is that if you might normally get exposed to something in the environment at 20 years old that would give you cancer by age 55, then if we cut the mutation rate in half, you might not get cancer until age 90, and you may even die of something else before that," Loeb explained.

The future cost of producing cancer drugs may have dropped in price with the laying of eggs from genetically-modified chickens.

Roslin Institute scientists have announced the successful creation of five generations of chickens that can lay eggs containing a specific protein needed to manufacture drugs used in the treatment of cancer. The Roslin Institute is the same research facility that cloned the Finn Dorset lamb named Dolly.

According to the BBC News report that states, "the work at Roslin shows it is now possible to use chickens as biofactories," more than one genetically-modified animal is being used as just such a factory for complex proteins needed to produce drugs.

It will be five-to-ten years before the drugs made from the protein of eggs from these genetically-modified chickens can be safely used, if clinical trials show favorable outcomes.

Once upon a time there were two groups of mice, all genetically engineered to develop prostate cancer. Each group was fed the same amount of calories. One group of mice lived in cages warmed to 80.6 degrees. The other group lived in cages kept at 71.6 degrees. The mice in the cooler quarters burned more calories to keep warm. And after three weeks, they weighed less than the toasty warm mice. They were also less likely to develop prostate cancer.

Then there were two other groups of mice, also genetically engineered to develop prostate cancer. Both groups were kept in cages with temperatures 80.6 degrees and 71.6 degrees -- like above. But these mice got to eat whatever their little hearts desired. The mice in cooler cages ate 30 percent more than the mice in warmer cages. They got just as fat as the warm mice. And they all got prostate cancer at the same rate, despite the extra calories.

The moral of the story is this -- being lean rather than obese has a greater protective effect against cancer. Excess calorie retention, rather than consumption, raises cancer risk. This moral stands in contrast to what most researchers believe -- that a restricted diet cuts the risk of and slows the growth of cancer and this is directly related to calorie intake.

Tim Nagy, Ph.D. and professor of nutrition sciences at the University of Alabama, Birmingham and lead researcher on the mice story says when you eat more calories than you burn, you store the extra calories as fat. It's the fat cells -- not the extra calories themselves -- that affect cancer risk.

It's not a good idea for humans to chill themselves to avoid cancer, Nagy says. But perhaps people could get the same effect by exercising more since that, too, burns calories.

Nagy's study appears in the January 1 issue of the journal Cancer Research.

Neuroblastoma is the most common tumor in infants younger than one year of age and a common solid tumor found in children. Neuroblastoma accounts for 7-10 percent of childhood cancers. It is a solid tumor that arises in a part of the nervous system outside of the brain.

St. Jude Children's Research Hospital says that Neuroblastoma tumors have been successfully treated in the lab with genetically modified cells that sought out and activated a chemotherapy drug placed directly at the cancer cells.

The chemotherapy drug, called CPT-11, is already used to treat cancers, doctors and scientists already know how the drugs behaves in humans. This should make it easier to translate the lab findings to the clinic. The researchers showed that the modified cells migrated to tumors regardless of how small the tumors were or where they were located in the body.

The homing ability of these cells, called neural stem-progenitor cells (NSPCs), can be used to target solid tumors that have metastasized. The researchers based their new treatment on work previously reported that showed certain NSPCs have a natural tendency to seek out damaged or cancerous areas in the brain.

Charlie Emrich, in Glowing chickens bring hope in fight against cancer, calls fluorescent chickens, "cool in a creepy, mad-scientist sort of way." When you consider that scientists have combined jellyfish DNA with chickens to create illuminated birds, you can kind of see it from Emrich's descriptive perspective.

The purpose of chickens that glow, is that scientists can track antibody-based therapies that might prove valuable in treating human cancers.

UC Davis Cancer Center Dr. Joseph Tuscano explains that, "One of the problems with modern drugs is that they're not very specific. Even aspirin is not very specific. Antibodies, on the other hand are highly, highly specific meaning that, like an archer's arrow, they can effectively target a disease. Antibody-based therapies are one of the biggest advances in cancer treatment in the last 40 years."

Emrich quotes researchers of the project and takes you through the purpose and process of genetically-modified glow-in-the-dark chickens in the potential development of antibody-based therapies to one day treat cancer here.