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March 8, 2001
Vol. 30, No. 16

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Human innovations may contribute to cancer rates

By Bob Hecker

A noted scientist says the prevalence of human prostate and breast cancer in the modern world may stem from a relatively recent "wrong turn" on the evolutionary trail.

Propelling us down that errant path, said Donald S. Coffey, have been some of our own innovations, such as fire, agriculture, hunting and raising livestock, all of which have affected our diet and lifestyle over the past several thousand years.

Coffey, one of the world's most distinguished researchers in the field of urology, contends that humans did not evolve and develop to live sedentary lives while subsisting on diets that are high in animal fat, processed food and fast food but low in fresh fruits and vegetables -- all characteristics of the Western lifestyle.

Coffey, who holds a triple professorship at the Johns Hopkins University School of Medicine in Baltimore, and is deputy director of its Oncology Center, was at Ohio State Feb. 21-22 to receive the Herbert and Maxine Block Lectureship Award for Distinguished Achievement in Cancer from the James Cancer Hospital and Solove Research Institute.

The annual Block Lectureship Award is funded by proceeds from the annual Herbert J. Block Memorial Golf Tournament, which was established in 1982 by the Block family of Columbus in honor of their father, who died of cancer.

"As resilient and adaptive as the human body is, there are some forces -- cheesesteak, for instance -- that nature never equipped us to handle," said Coffey, former president of the American Association for Cancer Research. "How ironic that we who have learned to defy gravity can be brought down, incrementally, by years of supersized bacon burgers and meat lover's pizzas. And today, we're far more likely to spend hours hunting for Web sites or TV channels than foraging for food."

In his quest to explain prostate cancer, which he said "seems to go hand-in-hand" with breast cancer in terms of incidence and mortality, Coffey has examined these diseases from a broad historical perspective.

"If there's one thing I want you to remember, it's that nothing means anything in biology unless being analyzed in light of its evolution," he said. "Every time I look at a problem in cancer, I back up and say,'How could this possibly have evolved this way?'"

He points out that mammals appeared about 65 million years ago and notes that only mammals have prostates and breasts, which apparently have evolved on parallel tracks. "Today, breast and prostate cancer seem to be two sides of the same coin: Countries with high rates of breast cancer tend to have a lot of prostate cancer, and countries with low rates of prostate cancer have relatively few cases of breast cancer," he explained.

Poring over zoo records from around the world, Coffey has found that no aging mammal in the zoo dies of prostate or breast cancer. One in 10 American men gets prostate cancer, and the only other mammal to develop clinical prostate cancer with any significant incidence is the dog -- "the pet that eats most from our table."

He blames this phenomenon mainly on diet. He maintains that humans have the makeup of an animal that should be a vegetarian, and their meat-eating tendencies seem to be a mistake that nature never accounted for.

"Most apes eat only fruits and vegetables. When we climbed down out of the trees, we became hunter-gatherers, but only recently have we started eating and processing meat in a big way," Coffey said.

In essence, he said, human technology has outrun human evolution.

Coffey noted that the American Cancer Society and National Cancer Institute have for decades been urging Americans to lower their cancer risk by changing their diet and lifestyle: cutting down on animal fats and dairy products while eating more fruits and vegetables and getting more exercise. "All of our experience in cancer prevention is telling us to return to the way we evolved," he said.

Coffey and his laboratory colleagues at Johns Hopkins have discovered a subtle change in prostate tissue -- a small inflammation that may stem from oxidative damage. "For some reason," he said, "there's a little autoimmune reaction, and this prostate inflammation makes highly reactive oxygen species-free radicals, which attack the DNA like crazy."

Realizing that soy protects against these free radicals, the researchers conducted an experiment in which rats given a soy-free diet developed lots of prostate inflammation, while those on a high-soy diet developed none. "So diet can control inflammation of the prostate. It can also turn protective enzymes on and off in the prostate," he said.

Coffey issued a plea for continued efforts in the study of cancer, which he describes as not only a genetic but an epigenetic disease, or one that also arises from factors other than inheritance.

"We have to open our eyes to see the whole picture of genetics, epigenetics, chromosomes, mutations, diet, DNA damage, the whole shtick," he said. "It is time to understand and implement prevention as well as therapy."

Bob Hecker is a technical editor for the OSU Medical Center.

 

Boundaries of disease hard to define, Rosenberg says

By Jeff Grabmeier

Although many people would like to believe that the mapping of the human genome will answer many of our questions about the nature of human disease, Harvard professor Charles Rosenberg has his doubts.

Science and medicine will not be able to settle questions about whether conditions such as substance abuse, chronic fatigue syndrome -- even road rage -- are diseases to be treated or something else entirely, Rosenberg said in a lecture at Ohio State March 1.

"We're going to continue to fight about these issues, no matter what the human genome project might turn up or no matter what scientific progress takes place in the next generation," he said.

Rosenberg, professor of history of science at Harvard, gave the first John C. Burnham Lecture in Medical History at the Medical Heritage Center in the Prior Health Sciences Library. The lecture series is sponsored by Ohio State's Department of History and the Medical Heritage Center.

Rosenberg discussed what he called "contested boundaries": those conditions that generate controversy and discussion regarding their status as diseases. An example is substance abuse, which is sometimes considered a chronic disease to be treated and sometimes as a crime to be punished.

Many, but not all, of these contested boundaries occur in psychiatry and behavioral medicine. "Psychiatry is conspicuously in the forefront of this guerrilla warfare about what is disease and what is not," Rosenberg said. Psychiatry is often called upon to negotiate what behavior is "normal" -- for example, in criminal cases involving defendants who may be mentally ill.

But, Rosenberg said, "we're never going to agree on issues of what behavior is normal."

The boundaries of disease are contested partly because of the demands of managed care, Rosenberg said. In a managed care system, a condition is either classified as a disease or it isn't, leaving no room for a gray area. The question becomes, "Can you code it as a disease and can you be reimbursed for treating it," he said.

One result is that groups and individuals lobby to make sure their particular condition is seen as a disease -- a process that makes the public uncomfortable.

"Many Americans find it unseemly that diagnoses should be shaped by advocacy groups and Web sites, and that disease-targeted research funding should be determined in part by lobbyists, lay advocates and journalists, and not the inexorable logic of laboratory findings."

The messiness of these contested boundaries explains the appeal behind the mapping of the human genome and other advances in human genetics, Rosenberg said. Many people have the hope that genetics will someday explain everything about human behavior and will end the debates about what is disease.

"There is almost a kind of utopianism in the world of genetics and gene therapy," he said. But because questions of contested boundaries involve culture as well as medicine, medical advances alone will not provide an answer.

"We're likely to keep fighting about the edges, the boundaries of these kinds of ailments."

 

 

 

 

 

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