Breast-feeding protects babies from cancer, but no one knows quite how. So when biologists in Catharina Svanborg’s lab saw mothers’ milk kill cancer cells, they knew they were onto something big.

When Catharina Svanborg and her research associates began mixing mothers' milk and cancer cells together seven years ago, she wasn't looking for a cure for cancer; she was after a way to fight germs. Nevertheless, the physician and immunologist at Lund University in Sweden has discovered that a previously taken-for-granted component of ordinary human breast milk compels cancer cells--every type of cancercell tested--to die. Now Svanborg must prove her discovery, demonstrating to wary scientists that her surprising find is for real. So far, it hasn't been easy.

“It’s an extremely important observation, interesting and provocative,” says breast cancer researcher David Salomon of the National Cancer Institute. “But it’s novel, and novelty always runs the risk of challenging the current dogma. A lot of times you run up against a brick wall of people who have tunnel vision.”

It doesn’t help that Svanborg’s lab is not a large, high-profile cancer research facility. In fact, it’s not a cancer lab at all; her specialty is an entirely different field, infectious disease. Says Salomon: “If this work had come from a well-known lab at the NCI, you’d have reporters calling six days to Sunday. You’d have scientists eager to collaborate. But it’s coming from a small lab in a foreign country. It’s like General Motors versus a garage operation.”


If so, this is the kind of garage you’d take your Porsche to. Tall, poised, and professional to the core, Svanborg leads a team of dedicated young researchers who have worked overtime to make their discovery matter. With the first phase of research finally finished, the group has decided to launch a fusillade of papers to scientific journals. Soon skeptics may have a tough time denying that they are onto something big.

Lund is dark and bleak in winter. A medieval town of 95,000 people (almost half are students), it nestles into Sweden’s southern tip. At its heart stands a twelfth-century cathedral with Romanesque towers that disappear into the gloomy low mist. As an occasional vehicle slowly skirts the town’s commons, bundled bicyclists glide by silently. People hunch forward against the cold. Across the way, university halls from the seventeenth century proclaim in stone Lund’s role as Scandinavia’s historical center of learning.

Bottles of breast milk stand ready for testing in Svanborg’s laboratory.

So it is a surprise, away from the town center, to come suddenly upon modern brick and concrete buildings: the university hospital, the library, science classrooms, laboratories. It was here nearly seven years ago that her student Anders Håkansson rushed into Svanborg’s office with perplexing news. He had been experimenting with human cancer cells, microbes, and mothers’ milk. (Like lab mice, cancer cells make popular experimental models because they come in standardized lab strains. In many important respects they behave just like other human cells, and they live indefinitely in lab dishes.) The idea was to pinpoint how the milk, a terrific germ-fighter, blocks bacteria from infecting other cells. But the cancer cells in this experiment were acting up. “Their volume was decreasing,” Håkansson recalls. “Their nuclei were shrinking. Something was wrong.”

When Svanborg sat down at the microscope, she diagnosed the problem immediately. “The cancer cells,” she announced in her calm, deliberate manner, “are committing suicide.”

Cells commit suicide all the time, a phenomenon called apoptosis, in which the body rids itself of old or unnecessary cells (see “Apoptosis,” on page 73). They simply fall apart and are recycled. For cancer cells, however, suicide is rare indeed. Their defining characteristic is uncontrolled reproduction. Yet somehow, the breast milk induced these cancer cells to take their own lives.

The circumstance opened up an enormous vista of mysteries—which pleased Svanborg to no end. “Discovery is at the heart of science. If you ask me for specific goals, I wouldn’t be able to name them. The process is fascinating enough.” Svanborg was eager to dive into finding out what in mothers’ milk was killing the cancer cells.

“And I always hope that new information will be practical and useful for people who need it,” she adds, the physician rising to the fore. Discerning the basic mechanism wasn’t enough—Svanborg wanted to find out if the cells might be induced to commit suicide on demand: Could the discovery be developed into a cancer cure?

Catharina Svanborg with Anders Håkansson, who first noticed the dying cells.

Attempting to do so would require manpower, and fewer than 20 people worked in Svanborg’s lab. Most were already involved in their own projects targeting infectious diseases. “If this were a pharmaceutical company, you could say, ‘Take a bunch of people and move them to this,’” Svanborg says. “But this is a university. These are students. If they already have thesis projects going, you can’t change their focus just like that.”

“You have freedom here,” says a graduate student. “Although we’re still in training, we are working as scientists. Catharina is very good at giving feedback, but we get to decide what experiments to do and how to do them.”

Which is also the way their professor likes it: “I want to facilitate creative environments. I like encouraging people to contribute based on who they are and what they think. After all, this cancer find is pure serendipity. And serendipity arises when people are in a situation that fosters creativity. Nobody can define how it happens, but there’s a lot of happiness involved.” So when Svanborg decided to go after the cancer, she couldn’t just pull her colleagues from their projects to help her. The undertaking would largely fall to her and Håkansson alone.

 



Milk Proteins
American Cancer Society
National Cancer Institute
Computer-generated image of alpha-lactalbumin protein