Cancer Research Findings Explained

By Athan Bezaitis on February 2, 2009 2:50 PM

Valter Longo, associate professor of gerontology and biology, discussed his latest findings on cancer research at a special community lecture hosted by the USC Davis School of Gerontology on Jan. 27.

Students, faculty and distinguished guests from the extended USC Davis School family listened to Longo discuss his findings, which have made international headlines in the past year.

In November, ABC News’ Nightline and ABC News’ World News With Charles Gibson featured Longo’s research in a report on dwarves in Ecuador with a rare condition known as Laron’s syndrome. People with this condition have shown immunity to cancer in all its forms.

Laron dwarfism affects fewer than 300 people worldwide, a third of whom live in remote villages in Ecuador’s southern Loja province. Sufferers of Laron’s syndrome lack a hormone called Insulin-like Growth Factor 1, or IGF1, which in excess amounts can lead to breast, prostate or bowel cancer at an early age.

“The dwarves grow to an average height of four feet, have perfectly proportioned bodies, live a normal lifespan and appear immune to all forms of cancer and also to diabetes,” Longo said. “Having less IGF1 could potentially mean less DNA damage, which promotes cancer in certain cases.”

Funded by a $4 million dollar grant from the National Institutes of Health, Longo and his team of researchers at the USC Davis School replicated the same mutation in mice. The mutant mice had far less cancer and lived twice as long as normal mice.

The discovery of a human population with this mutation, he said, may have advanced his research by 20 years. “We are trying to develop drugs that mimic the same mutations with the intention of using them to prevent cancer,” he said.

Longo also discussed a promising new approach to protecting healthy cells from the harmful side effects of chemotherapy through fasting.

Starved healthy cells go into survival mode, Longo explained, characterized by extreme resistance to stresses. In essence, these cells are waiting out the lean period, much like hibernating animals. But cancerous tumors respond differently to starvation; they do not stop growing, nor do they hibernate because their genetic pathways are stuck in an “on” mode.

Longo realized that the starvation response might differentiate healthy cells from cancer cells by their increased stress resistance and that healthy cells might withstand much more chemotherapy than cancer cells.

A three-year, $600,000 grant from the V Foundation for Cancer Research is funding clinical trials currently under way at the USC Norris Hospital.

Longo told of a handful of cancer patients, including a physician, who have sought him out for counseling on the experimental treatment. He officially does not endorse fasting before chemotherapy because clinical trials are not yet conclusive. However, people who believe in the promising results of his early findings have attempted the new method on their own and have offered anecdotal evidence of minimal side effects from fasting for a fixed period of time before and after chemotherapy.

“The hope is for oncologists to potentially control cancers, making chemotherapy less toxic to the rest of the body,” he said. “The resulting data will also serve as an impetus for the development of drugs that mimic the effects of fasting.”

Longo’s research, said USC Davis School Dean Gerald C. Davison after the lecture, exemplifies the best of what is referred to as “out of the box thinking.”

“If Valter is right, physicians will be able to provide stronger regimens of chemotherapy without causing the excruciating illnesses that now limit what patients are able and willing to withstand.”

TAGS: medicine, research

Search search

Search prior to August 2008