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High-tech glasses developed at Washington University School of Medicine in St. Louis may help surgeons visualize cancer cells, whichglow blue when viewed through the eyewear.

The wearable technology, so new it’s yet unnamed, was used during surgery for the first time today at Alvin J. Siteman Cancer Centerat Barnes-Jewish Hospital and Washington University School of Medicine.
Cancer cells are notoriously difficult to see, even under high-powered magnification. The glasses are designed to make it easier for surgeons to distinguish cancer cells from healthy cells, helping to ensure that no stray tumor cells are left behind during surgery.
ImageHigh-tech glasses developed at the School of Medicine help breast surgeon Julie Margenthaler, MD, visualize cancer cells in a patient Feb. 10.

Nuclear bomb tests carried out during the cold war have had an unexpected benefit. A radioactive carbon isotope expelled by the blasts has been used to date the age of adult human brain cells, providing the first definitive evidence that we generate new brain cells throughout our lives. The study also provides the first model of the dynamics of the process, showing that the regeneration of neurons does not drop off with age as sharply as expected.

In mammals, most types of brain cell are created at or soon after birth and are never renewed. But studies in rodents and monkeys have shown that in two regions new neurons continue to be created even in adulthood – the hippocampus, which is involved in learning and the formation of new memories, and the olfactory bulb, which processes smell.

However, there has been some controversy over whether the same is true for humans. Fifteen years ago a study found evidence for such neurogenesis in adults up to the age of 72 (Nature Medicine, doi.org/b7hjfz), but the research relied on a chemical called bromodeoxyuridine (BrdU) to label neurons. BrdU was used at the time to track the spread of tumours in people with cancer, but it was banned shortly after and so the study was never repeated, leading some researchers to question the results.

The new study settles the debate. "The existence of adult hippocampal neurogenesis in humans is not arguable this time," says Sandrine Thuret at King's College London, who was not involved in the work.

Instead of chemical labelling, Jonas Frisén at the Karolinska Institute in Stockholm, Sweden, and colleagues used a by-product of the above-ground nuclear bomb tests carried out by the US, UK and Soviet Union between 1945 and 1963. As a result of these detonations, atmospheric levels of the radioactive isotope carbon-14 increased dramatically during this period. It has decreased steadily since.

Carbon-14 enters the food chain and eventually finds its way into our cells, which integrate carbon-14 atoms into their DNA when a parent cell splits into two new daughter cells. The amount of carbon-14 in the atmosphere is therefore mirrored in the cells at the time they are born.

By analysing brain tissue using mass spectrometry equipment, the team was able to measure the number of carbon-14 atoms trapped in different populations of cells in different brain regions.

They could then compare this figure to known data for atmospheric levels of carbon-14 to date the birth of a cell in different people to within about a year. The level of carbon-14 is higher in older cells grown closer to the peak of nuclear bomb testing than in cells born more recently.

Frisén's team previously used this method to show that humans are the only known mammal in which neurogenesis does not occur in the adult olfactory bulb, since the cells in this brain region were the same age.

The goal is to put the vast collection of data on genetic variations and health into databases open to researchers and doctors all over the world.

More than 70 medical, research and advocacy organizations active in 41 countries and including the National Institutes of Health announced Wednesday that they had agreed to create an organized way to share genetic and clinical information. Their aim is to put the vast and growing trove of data on genetic variations and health into databases — with the consent of the study subjects — that would be open to researchers and doctors all over the world, not just to those who created them.

Millions more people are expected to get their genes decoded in coming years, and the fear is that this avalanche of genetic and clinical data about people and how they respond to treatments will be hopelessly fragmented and impede the advance of medical science. This ambitious effort hopes to standardize the data and make them widely available.

“We are strong supporters of this global alliance,” said Dr. Francis Collins, director of the National Institutes of Health. “There is lots of momentum now, and we really do want to move quickly.”

In just the past few years, the price of determining the sequence of genetic letters that make up human DNA has dropped a millionfold, said Dr. David Altshuler, deputy director and chief academic officer at the Broad Institute of Harvard and M.I.T. As a result, instead of having access to just a few human genomes — the complete genetic material of a person, including genes and regions that control genes — researchers can now study tens of thousands of them, along with clinical data on peoples’ health and how they fared on various treatments.

In the next few years, Dr. Altshuler said, researchers expect that millions of people will have their genomes sequenced.

“The question is whether and how we make it possible to learn from these data as they grow, in a manner that respects the autonomy and privacy choices of each participant,” he said. No one wants to put DNA sequences and clinical data on the Internet without the permission of patients, he said, so it also is important to allow people to decide if they want their data — with no names or obvious identifiers attached — to be available to researchers.

Medical researchers say the best way forward is to have shared databases. Do patients with a particular genetic aberration tend to do well with a particular therapy? Do patients with another mutation have greater odds of developing cancer?

Dr. Collins said that cancers are so genetically complex that, most of the time, a mutation seen in a cancer patient will be uncommon. To figure out its significance, data from hundreds of thousands of patients — the world’s collected data — on that mutation are needed.

Here’s a chart that’s a little disturbing: The interactive graphic above, created by biotechnologist David Taylor and appearing first on his data-visualization blog, illustrates how common and deadly various types of cancer are. Each pie chart represents an organ (matched for color) and is sized according to the incidence of...

U.S. researchers have developed a novel lung cancer treatment that uses nanoparticles to deliver an inhaled form of chemotherapy.

The scientists from Oregon State University, Rutgers University in New Jersey and the Cancer Institute of New Jersey developed "nanostructured lipid nanocarriers" that find cancer cells in the lung, attach to them and deliver drugs locally. With the inhaled substance, the patient receives an unadulterated form of the cancer drug compared with conventional intravenous administration, which can accumulate in other organs such as the liver or kidneys with toxic effects.

What's more, the nanoparticle comes with a bundle of small interfering RNA, siRNA, which helps silence certain genes to make the cancer cells more vulnerable to the drugs. Overall, the study showed 83% of the drug reaching its target in the lungs as opposed to 23% with the traditional approach, according to the article published in the Journal of Controlled Release.

"A drug delivery system that can be inhaled is a much more efficient approach, targeting just the cancer cells as much as possible," said co-author Oleh Taratula. "Other chemotherapeutic approaches only tend to suppress tumors, but this system appears to eliminate it."

The team has applied for a patent for the delivery platform, but human clinical trials will have to await further testing.