Enormous strides have been made over the past 20 years in identifying carcinogens -- substances, such as tobacco, that cause cancer -- and developing surgical, chemotherapeutic and radiation treatments for cancer. The field is also littered with the corpses of some celebrated also-rans -- such as krebiozen and laetrile -- that captured the public curiosity for a time. During the same period interferon, a family of proteins, has struggled for identity and respectability as a cancer treatment. Furtively at first, and now with increasing command, interferon presents itself as a real competitor for the minds and dollars of the cancer research community.

"Interferon: The New Hope for Cancer" is the story of that substance. Its authors, science writer Mike Edelhart and Jean Lindenmann, who helped first isolate interferon in 1956, write with knowledge about their subject. A strong point and a major weakness in their work is that they are unabashed admirers of interferon. Their enthusiasm makes for good reading, but at times they present a rosy picture that is as yet unsubstantiated by the facts.

For more than a century, biomedical observers have noted that a second viral disease never attacks an organism when one is already present. Researchers in the 1930s used the term "virus interference" to describe this phenomenon. In 1956, Lindenmann, a young Swiss researcher, spent a year, at England's National Institute for Medical Research working with Britain's Alick Isaacs using virus-coated red blood cells. They isolated a highly impure biological soup that curtailed the activity of a second virus. In 1957, the pair published their discovery, and the concept of interferon has been with us since.

The substance has had a checkered career. As Edelhart and Lindenmann observe, "In science, as in show business, there really is no such thing as an over-night sensation." In addition to the obvious anti-viral use of interferon, it was early appreciated that the substance had potential for fighting tumors. Indeed interferons are known to be among the most potent biologically active compounds. But research has been agonizingly slow because interferon has been extraordinarily difficult to produce and almost impossible to purify. Most of the interferon used in recent years has come from one laboratory in Finland that harvests it from fresh human blood cells. While this process has yielded sufficient quantities to undertake some testing, the amounts have been small and the expense has been considerable.

All of that is changing rapidly because of the emergence of genetically engineered -- cloned -- interferon. Biologists have been able to splice the gene for human interferon production into the nuclear material of a bacterial cell. The bacterium becomes a tiny factory for the production of the substance. The technology is new and far from being debugged, but its very existence makes interferon more like penicillin and less like a moon landing. Genetically produced interferon is currently undergoing its first human clinical trials, and it seems likely that within a few years it will be readily available in a pure and potent form.

The story of the entrepreneurial tide that has swept up interferon is as topical and fascinating as that of the protein itself. Edelhart and Lindenmann cover these events as well as anything in the book. As a symbol and as an example of the nascent bio-industrial complex, they describe a press conference held in January 1980 by a new corporation, Biogen, SA, to announce the successful production of interferon. "The press conference represented a break with the past in two completely different arenas," the authors observe. "In science, it marked the moment in which genetic engineering moved from the shadowy world of lab studies to the front pages, and interferon from long-range scarcity to short-term abundance. In business, it denoted the first public appearance of the potentially enormous bioresearch industry, which could become as intertwined with our future medical care and pocketbooks as today's computer and electronics industries." The possibilities of interferon, they go on to point out, have stimulated a host of new commercial relationships involving venture capital and universities, multinational corporations and medical centers, megabucks and biology. The permutations of this story, ranging from medical ethics to lab drama, are as exciting and important as interferon itself.

As for interferon and cancer, the story is far from over. Despite the book's sanguine editorializing, human studies thus far show only modest anti-tumor effects. Larger quantities of purified interferon may well prove to be important agents against certain cancers. As of now that possibility remains in the realm of speculation. Interferon certainly is not krebiozen, but it has not yet proven itself to be penicillin either.