Just 48 hours of fasting was enough to protect mice from the side effects of an intensive chemotherapy treatment that wiped out much of the cancer in their bodies, according to a study published yesterday.
Should the same results be found in humans, it could protect cancer patients from the ravages of chemotherapy drugs and also potentially allow for significantly more aggressive treatment.
"We were able to treat with a very high dose of chemo and the animals were running around like we didn't give them anything," said lead author Valter Longo, an Italian researcher at the University of Southern California.
PHOTO :AP
"Everyone was really focusing on how to kill cancer cells. Instead, we said let's leave that alone and kill the cancer cells the same way but protect everything else much better."
Longo's team has already applied for approval to run a small clinical trial on cancer patients in California.
They are also looking at ways to get the same protective effects without actually fasting by administering either a drug or a highly specific diet.
"We're exploiting the ability of every organism that's ever been tested to go into this starvation response mode which is usually associated, counterintuitively, with the high resistance to almost anything you throw at them," he said in a telephone interview.
The starvation response has already been shown to protect against stresses like heat shock, block the development of spontaneous tumors and protect liver cell death caused by acetaminophen.
Longo and his team tested the starvation response to chemotherapy drugs in yeast, human and rat cells and then mice injected with a highly aggressive form of cancer that affects children.
The results were remarkable.
The starved yeast were able to withstand up to 1,000 times more stress and toxicity.
The starved human and rat cells had a tenfold increase in resistance to chemotherapy while cancer cells received no protection and, in some cases, were weakened by the starvation.
The starved mice showed "no visible sign of stress or pain" after chemo treatments which were either three times or five times the comparatively maximum dose allowed in humans, according to the study in the Proceedings of the National Academy of Sciences.
While they lost 20 percent of their body weight in two days of fasting, the mice regained most of the weight in the four days following chemotherapy. Those starved for 60 hours lost 40 percent of their weight but regained it within a week.
More than half of the mice that were not starved before treatment died of toxicity and those that survived lost 20 percent of their body weight following treatment. Only one of the 28 starved mice died.
The single chemotherapy treatment was not sufficient to wipe out all of the cancer that had been injected into the mice.
However, it did double the life expectancy of the starved mice that lived up to 60 days after being injected with an aggressive cancer that usually kills mice in less than 30 days.
Longo's team is currently working on another study to see if multiple chemotherapy treatments can totally cure the starved mice of their cancer.
"Ideally, you want to kill all the cancer cells, but if you think about it, it might not even be necessary to get to that level," he said.
"You can't necessarily expect to kill all the cancer cells based on the cancer, but this could allow you to keep it under control - if it works - by doing many, many different cycles of chemo."
The simplicity of the treatment will help it reach patients quickly should it prove to be safe and effective.
"We should have pretty solid results just a few weeks after we start the study," Longo said, explaining that standard blood tests can show whether or not patients were protected by fasting.
"Within a year, you could have this into many different hospitals, if it works, and that's a big if," he said.
The initial trial will not risk increasing chemotherapy doses but simply test for the protective value of a brief period of starvation. It will take more testing to see if starvation can be used to safely increase the doses and frequency of chemo treatments.
"Eventually this is going to work," he said.
"We just have to find the equivalent ... is it 48 hours, or is it 48 hours plus maybe targeting certain receptors in certain genes? We know the system pretty well ... we just have to find the equivalent. I'm confident that within a year or two we'll have that."
That US assistance was a model for Taiwan’s spectacular development success was early recognized by policymakers and analysts. In a report to the US Congress for the fiscal year 1962, former President John F. Kennedy noted Taiwan’s “rapid economic growth,” was “producing a substantial net gain in living.” Kennedy had a stake in Taiwan’s achievements and the US’ official development assistance (ODA) in general: In September 1961, his entreaty to make the 1960s a “decade of development,” and an accompanying proposal for dedicated legislation to this end, had been formalized by congressional passage of the Foreign Assistance Act. Two
March 31 to April 6 On May 13, 1950, National Taiwan University Hospital otolaryngologist Su You-peng (蘇友鵬) was summoned to the director’s office. He thought someone had complained about him practicing the violin at night, but when he entered the room, he knew something was terribly wrong. He saw several burly men who appeared to be government secret agents, and three other resident doctors: internist Hsu Chiang (許強), dermatologist Hu Pao-chen (胡寶珍) and ophthalmologist Hu Hsin-lin (胡鑫麟). They were handcuffed, herded onto two jeeps and taken to the Secrecy Bureau (保密局) for questioning. Su was still in his doctor’s robes at
Last week the Democratic Progressive Party (DPP) said that the budget cuts voted for by the China-aligned parties in the legislature, are intended to force the DPP to hike electricity rates. The public would then blame it for the rate hike. It’s fairly clear that the first part of that is correct. Slashing the budget of state-run Taiwan Power Co (Taipower, 台電) is a move intended to cause discontent with the DPP when electricity rates go up. Taipower’s debt, NT$422.9 billion (US$12.78 billion), is one of the numerous permanent crises created by the nation’s construction-industrial state and the developmentalist mentality it
Experts say that the devastating earthquake in Myanmar on Friday was likely the strongest to hit the country in decades, with disaster modeling suggesting thousands could be dead. Automatic assessments from the US Geological Survey (USGS) said the shallow 7.7-magnitude quake northwest of the central Myanmar city of Sagaing triggered a red alert for shaking-related fatalities and economic losses. “High casualties and extensive damage are probable and the disaster is likely widespread,” it said, locating the epicentre near the central Myanmar city of Mandalay, home to more than a million people. Myanmar’s ruling junta said on Saturday morning that the number killed had