Gene May Help Defeat Malignancies

BOSTON —  Scientists said Thursday that they have isolated a gene that instructs the body to build tiny new blood vessels, a crucial step in cancer growth, and they say this could open new strategies to defeat malignancies.

The researchers who purified and analyzed the protein, named angiogenin, which this gene controls, say it is the first time that an organ-forming protein has been understood in detail.

The discovery is the culmination of 10 years of work by Dr. Bert L. Vallee and colleagues at Harvard Medical School. Three scientific papers describing their research are being published in the latest issue of the journal Biochemistry.

Experts say the work represents a major step in the study of angiogenesis, or blood vessel formation, which was pioneered two decades ago by Dr. Judah Folkman, another Harvard researcher.

“It’s a stunning achievement,” Folkman said. “I think it’s very important for the whole field, because it will enlarge everyone’s thinking about how tumors send the signal to keep blood vessels growing in toward them.”

Tumors need a blood supply to grow. Without a network of tiny blood vessels, known as capillaries, cancers would never become large. Cancers send out a chemical signal that encourages surrounding tissue to send capillaries toward them.

Experts theorize that if such chemical signals could be neutralized, cancers would stop growing.

“I would fondly hope that this will prove possible,” Vallee said, adding that much work remains.