Will Interferon Kill Cancer? Finnish Dr. Kari Cantell Is Helping the World Find Out
The war against cancer is being waged worldwide, and one of the most important battles is being fought—and won—in Finland. There virologist Kari Cantell, 46, has perfected a method of producing interferon, a promising drug being studied in at least a dozen nations.
Interferon, which has already demonstrated its potency against virus infections, is the name given to a family of proteins naturally secreted by animal cells. When a cell is under attack, these proteins apparently signal the cell to defend itself or slow down the growth rate (possibly helpful in resisting cancer). Interferon was first identified by two scientists in England in 1957. But because it is “species specific”—in order to be effective in humans it must come from human cells, which normally produce only minuscule amounts—researchers were hampered by a lack of the raw material.
Cantell, now chief virus specialist at Finland’s Central Public Health Lab in Helsinki, began working on the problem in 1958. He became intrigued by the white cells’ role in infection fighting. By the late ’60s he was concentrating on human white blood cells, which the Finnish Red Cross made available since, luckily for Cantell, there was little medical demand for them elsewhere. “I wouldn’t have even started working with white cells,” he admits, “if there hadn’t been the possibility of obtaining them in large quantities.”
He spent more than five years trying to coax more interferon out of the white blood cells. Then finally he tried infecting them with the Sendai virus and discovered that the cells increased interferon output three-to tenfold. At last Cantell had the clue to what he needed: a dependable source. “There were,” Cantell admits, “hundreds and hundreds of experiments, and we learned mainly through trial and error.”
Dr. Jussi Huttunen, director of the Central Public Health Lab, recalls Cantell’s single-mindedness. “He continued to have faith in it, even in the bad days,” Huttunen says. “He is able to stimulate others and draw things together. Good people have good luck.”
As a boy Cantell persevered primarily at sports—soccer, gymnastics and pesäpallo, a Finnish variation of baseball. His father taught history and Latin in their hometown, Mikkeli. When a broken arm ended Cantell’s plans for a sports career, he went to the University of Helsinki with the vague aim of becoming a doctor. Randomly assigned in his fourth year to prepare a lecture on bacterial viruses, he found them so fascinating that he went on to do his doctoral thesis on mumps virus. He then spent two years at Philadelphia’s Children’s Hospital specializing in virology before returning to Helsinki as head of the public health virus laboratory.
In the Soviet Union a primitive form of interferon is sold over the counter as an anti-flu drug, though there has been no conclusive evidence that it works. But Cantell and the Finnish Red Cross, now producing 250 billion units (5,285 quarts) a year, have provided the great bulk of pure interferon used for clinical studies on humans, including a $2 million batch bought last year by the American Cancer Society. “Production is the bottleneck,” says Cantell, who finds it “stupid and irritating” that until recently nobody else has tried to produce the substance in large-scale volume.
Other animals, fish and even plants make their own interferon, but its capabilities are still not completely understood. To date it has shown potential as a treatment for colds and chicken pox as well as hepatitis, herpes infections and rabies. Preliminary tests—some carried out by Cantell’s close collaborator, Swedish tumor specialist Hans Strander—indicate it may be effective against many forms of cancer, while causing far less disruptive side effects.
Researchers caution that it is not a cure-all. “It will take a lot more time,” Cantell says, “to refine its use—in what doses, when and where.” But he is determined to keep riding the No. 63 bus from his home on the outskirts of Helsinki to his lab until the answers are found. “Many eminent people once considered interferon good theoretically but of no clinical value, on the ground that enough of it couldn’t be produced,” Cantell explains. “I belonged to the minority who believed in its eventual practicability, and maybe I have the stubbornness of a marathon runner. I don’t have many ideas but I persist with the ones I have.”