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A stride to understand the cancer and move towards its prevention, this time experts from around the world involved in searching the genome of cancer have analyzed the mutational signatures, the processes of mutation in the DNA of cells (which are always in the origin of cancer) and they follow a fixed pattern.

Adverse life experiences, particularly those in childhood, contribute to disease morbidity and mortality [1, 2, 3, 4, 5, 6, 7]. There is considerable interest in understanding the mechanisms through which they do so, as it remains unclear how illness becomes apparent decades after the presumed initiating event. Long-standing hypotheses include chronic activation of the hypothalamic-pituitary-adrenal axis [8, 9, 10] and alterations of neuroimmune function [11]. Molecular signatures of stressful life experiences and their relation to disease are therefore of special interest to clarify the causal relationship between signature, disease, and stress.

A new study from the Monell Center, the U.S. Department of Agriculture (USDA), and collaborating institutions reports a uniquely identifiable odor signature from mouse models of Alzheimer's disease. The odor signature appears in urine before significant development of Alzheimer-related brain pathology, suggesting that it may be possible to develop a non-invasive tool for early diagnosis of Alzheimer's disease.

Within a year, Stein's team had designed a clinical trial protocol that turned standard research practices around 180 degrees, launching what it now calls the Signature Clinical Trial Program. Instead of a patient traveling to one of several research sites, Novartis would send the investigational drugs to his or her local oncologist's office. Instead of testing hundreds or thousands of genetically unscreened patients, the company would accept only patients who had the genetic markers the drugs were supposed to target. Instead of waiting months, patients could access the treatments in two or three weeks. Instead of running a large-scale trial to investigate one or two questions, clinicians could conduct smaller, rapid proof-of-concept studies to quickly rule out the tumor types that don't respond to a study agent and identify other tumor types that are potentially treatable with the drug and worthy of further study.

New immune system-boosting cancer drugs have in clinical trials saved the lives of many people with seemingly untreatable melanoma or lung cancer, but the drugs seem useless against colon cancer. One exception-a man with colon cancer whose metastatic tumors vanished for several years after he was treated in 2007-piqued researchers' interest. They suspected his recovery might have to do with the large number of mutations in his tumors. Now, a small clinical trial suggests that even cancer patients with types of tumors that were thought to be impervious to the new drugs could benefit if those malignancies have the right error-riddled DNA signature, a result that could help 3% to 4% of cancer patients.

By analyzing the chemical signatures of six coral reef cores taken from multiple sites in the Pacific Ocean around Panama, the scientists found an extreme weather event associated with what we would call La Niña today triggered the reef collapse. A series of events similar to El Niño continued to suppress the reef for the next two millenniums.

"Now we have evidence that urinary odor signatures can be altered by changes in the brain characteristic of Alzheimer's disease," said Dr. Bruce Kimball, a chemical ecologist at the USDA National Wildlife Research Center, in a news release. "This finding may also have implications for other neurologic diseases."

Men shed more bacteria into their surroundings than women do, studies have shown. Now scientists have found that men and women have different effects on the variety of bacteria inside a home, too. The variation comes down to skin biology and "perhaps to body size and hygiene practices," note researchers who sequenced the genes in dust that had settled on the tops of doors in 1,200 homes across the U.S. Dogs apparently alter indoor bacteria more extensively than humans or cats. The bacterial signatures of each of these living beings are unique enough that by simply testing dust in a home, investigators can accurately predict if more women or men live there and if dogs or cats do as well.