http://online.wsj.com/article/SB10001424052748703961104576148422547757048.html?mod=ITP_pageone_1
The fourth and fifth paragraph from the bottom...

A small population of Ecuadoreans afflicted with a dwarfism disorder almost never get cancer or diabetes, a finding that may point the way to new treatments for both diseases, according to a new study.

The research focused on a group of about 100 Ecuadoreans with Laron syndrome, a rare genetic mutation that prevents their bodies from properly using growth hormone. But this genetic defect also appears to protect against diabetes and cancer.


A seven-year old Ecuadorean boy, born with Laron syndrome, was one of about 100 patients studied by Dr. Guevara-Aguirre. 
.Based on data collected over about 22 years, scientists found not a single case of diabetes and only one nonlethal case of cancer among the Laron individuals. A similar analysis of 1,600 relatives—who lived in the same area and have normal stature—showed that 5% got diabetes and 17% got cancer, the same rate as the general Ecuadorean population.

The study was published Wednesday in the journal Science Translational Medicine.

Previous experiments with yeast and mice suggested that blocking growth hormone could provide health benefits. For example, scientists extended the life span in growth-factor-deficient mice by as much as 40%. But there has been little scientific evidence that the same mechanism could potentially work in people, until now.

The results in yeast, worms, mice and now the Ecuadorean group suggests that "Nature has given to us an evolutionarily conserved pathway" which, if exploited correctly, may help to prevent diabetes and cancer, said Jaime Guevara-Aguirre, an Ecuadorean physician and co-author of the study.

Valter Longo, a cell biologist at the University of Southern California and co-author of the study, said it might be possible to use drugs or controlled diets— or a combination of the two—to achieve similar protection in full-grown adults. Any such treatments, though, are likely years away.

Back in 1987, Dr. Guevara-Aguirre began studying the Laron individuals to better understand the reasons for their stunted growth. Genetic analysis suggests they are descended from Spanish conversos—Jews who converted to Christianity to avoid the Inquisition. There are only about 300 people with the Laron mutation in the world, of which a third live in a remote area of the Ecuadorean Andes.

In California, meanwhile, Dr. Longo was seeking a way to properly test whether people who were deficient in growth hormone lived longer. Though 3,500 miles apart, the two scientists soon realized there was a tantalizing overlap in their research interests.

 
Ecuadorean physician Jaime Guevara-Aguirre with patients affected by Laron syndrome. He has been studying such subjects since 1987.
.In 2006, Dr. Longo invited Dr. Guevara-Aguirre to California. During his visit, the Ecuadorean physician said "he didn't remember seeing a case of cancer or diabetes in the Laron population," Dr. Longo recalled. "That's exactly what I was hoping for."

To seek out why the Laron patients were so remarkably free of cancer and diabetes, the pair teamed up. They took saliva and blood samples of the patients and analyzed their genes. Dr. Guevara-Aguirre already had detailed health records on the 100 individuals; the pair then surveyed those patients' relatives to assess their long-term health.

The finding on diabetes was especially striking. Being overweight is a major risk factor for the disease. Yet, while the Laron patients had a higher level of obesity than their relatives, not one in the group suffered from diabetes. "If you say that to a diabetes doctor, they'd find it hard to believe," Dr. Longo said.

In the Translational Science paper, the authors used cell studies to show that family members with the dwarfism mutation had lower amounts of IGF-1, or insulin-like growth factor 1, a substance crucial to childhood growth. The patients also had lower insulin concentrations and higher insulin sensitivity.

According to the paper, the low IGF-1 and insulin concentrations helped prevent oxidative DNA damage, and also hastened cell death—another way the body limits DNA damage. 

The authors stopped short of saying that lower IGF-1 and insulin concentration levels were responsible for the lack of cancer and diabetes in the Laron patients. But they pointed out that the results coincide with similar findings in experiments with lower organisms. For example, lower IGF-1 and insulin concentration levels have been shown to increase the longevity of yeast, worms and mice.

That may provide a clue about how age-related diseases could be tackled with diet or drugs. Studies have shown that IGF-1 levels in people decline if a person stops eating for a few days, or reduces protein intake. And a recent study by Dr. Longo showed that fasting leads to rapid changes in growth factors similar to those caused by the Laron mutation.

But fasting or reducing protein in the diet carries its own risks, including lower blood pressure and a weakened immune system. An alternative approach would be to find a drug that reduces growth-hormone activity, once an adult stops growing.

Dr. Longo suggests that a preventive treatment could target adults with high growth-hormone activity in order to bring it down to an average level.

Pfizer Inc. sells a drug, Somavert, that blocks growth-hormone activity in people and is used to treat acromegaly, a condition related to gigantism. Dr. Longo said he hopes to persuade Pfizer to participate in a trial to test the potential beneficial effects of Somavert in patients undergoing chemotherapy. 

The hope is that the drug will reduce some of the nasty side effects of chemotherapy, a treatment that also has a toxic effect on normal cells. "We've shown that if you reduce IGF-1 it causes some protection for human cells," says Dr. Longo. "Can we use the same to protect against the toxic effects" of chemotherapy?

One unusual coda to the Ecuadorean story is that even though the Laron patients don't develop diabetes or cancer, they don't live any longer than their relatives. They tend to die more often from substance abuse and accidents, the researchers said.