A Fishy Tale, More Lab Stories from the Good Old Days

A Fishy Tale

The popularity of taking shark cartilage extract to prevent or treat cancer is a triumph of marketing and pseudoscience over reason, with a tragic fallout for both sharks and humans. That's the conclusion made by biologist Gary K. Ostrander of Johns Hopkins University in a press release about a paper he coauthored in the Dec. 1 issue of Cancer Research [64, 8485 (2004)].

"People read on the Internet or hear on television that taking crude shark cartilage extract can cure them of cancer, and they believe it without demanding to see the science behind the claims," Ostrander opines. The consequences have been a decline in shark populations and cancer patients veering away from proven treatments, he says.

Ostrander attributes the folk remedy to a myth started by I. William Lane in his 1992 book titled "Sharks Don't Get Cancer." But the truth is sharks do get cancer, as Ostrander and his colleagues have pointed out for several years and set out to prove once and for all in their paper. Lane acknowledges in the book that sharks do get cancer, albeit at low rates, and he has admitted that the title was a marketing ploy for his shark extract supplement called BeneFin.

The press release brought to mind the early work of Massachusetts Institute of Technology chemical engineer Robert S. Langer, of controlled drug release and tissue engineering fame, who, as a postdoc in M. Judah Folkman's lab at Harvard Medical School in 1974, was given a task of extracting a potential anticancer drug from cartilage. Folkman's lab had found that proteins from rabbit cartilage worked as an antiangiogenesis agent--that is, the extract prevented growth of new blood vessels around tumors and choked them off.

Langer needed large quantities of cartilage extract for further study, so he began using cow shoulders from local slaughterhouses. But he still couldn't get enough cartilage, so he started using sharks as well. Suffice it to say that Langer and Folkman finally got enough purified cartilage extract to report the first angiogensis inhibitor in a Science paper in 1976. It turns out that the Langer-Folkman paper inspired the entrepreneurial Lane, a biochemist and one-time vice president at W.R. Grace, to start peddling crude shark extract as a cancer-fighting supplement.

Purified compounds from cartilage are being studied for their anticancer activity, Ostrander says, but crude shark extract taken by mouth has been shown in clinical studies to have no discernible anticancer benefits. The details of Langer's cow and shark expeditions are outlined in the book "Dr. Folkman's War: Angiogenesis and the Struggle to Defeat Cancer," by Robert Cooke.

More lab stories from the good old days

Recent discussions here about the liberal handling of mercury in the lab and classroom inspired Frank R. Stermitz of Fort Collins, Colo., to share some remembrances of working conditions years ago. "In the 1940s, I had a summer job at the state highway department testing lab where we studied tar binders for use in highway surfacing," Stermitz notes. "Graduated cylinders filled with mercury were used by a coworker to measure the volume and density of compacted pellets, and excess mercury overflowed from the cylinders onto the floor around his bench." Stermitz says his job was to clean tarry flasks, which was most easily done by soaking them in a vat of warm benzene on the open lab bench.

During a different summer, Stermitz worked at a "bag house" at a lead smelter, where he handled bags that collected cadmium dust as a by-product of lead ore processing. He also shoveled out powder at the bottom of a Cottrell precipitator, where arsenic was a prominent component.

Stermitz apparently turned out okay, as he became a chemistry professor at Colorado State University. One of his accomplishments was codiscovery of 5´-methoxyhydnocarpin, a natural product isolated from the leaves of barberry plants. Coupled with antibiotics, the compound inactivates strains of Staphylococcus aureus that are largely responsible for staph infections contracted in hospitals.

This week's column was written by Steve Ritter . Please send comments and suggestions to newscripts@acs.org.