Jekyll-Hyde Protein May Contribute to Leukemia

FRIDAY, Oct. 21 (HealthDay News) -- Scientists say they''ve uncovered the Jekyll-and-Hyde nature of a protein that can both fight off and contribute to the development of cancer.

The findings, while preliminary, could eventually help in the battle against one of the deadliest forms of leukemia.

The goal will be to prevent the protein from taking on its "evil role" and helping to create tumors, said Stanford University pathology and pediatrics professor Dr. Michael Cleary, co-author of a study in the Oct. 21 issue of Cell.

Leukemia, a form of blood and bone marrow cancer, is not as deadly as it once was. But it continues to kill about 22,500 Americans each year, and remains the deadliest form of cancer in people under the age of 20, according to the Leukemia & Lymphoma Society.

Cleary and his colleagues examined a protein known as menin that has a reputation as a tumor-suppressor. Scientists think it keeps endocrine cancers -- those of the hormone system -- from developing.

But the researchers, using mice cells, found that in certain situations, menin also interacts with another protein, known as MLL, to create leukemia tumors.

In essence, menin loses its tumor-suppressing powers. When the protein was removed, however, cancer cells stopped being cancerous.

Understanding the dual role of menin is important because it would help scientists figure out how leukemia disrupts a "yin-yang" balance and allows cancer to grow, said Deborah Banker, vice president of research communication for the Leukemia & Lymphoma Society.

The findings are also important because they help explain what''s happening in the estimated 5 percent to 10 percent of leukemia cases that are caused by disruptions involving the MLL protein. These cases, involving acute leukemia, are especially difficult to treat, Banker said.

Will the study, funded by federal and private grants, actually lead to a better treatment for leukemia? That''s far from clear.

But it does add to current knowledge about how leukemia isn''t just one kind of cancer, but several dozen that each work in different ways, Banker said. The key, she said, is finding a treatment that will combat them all.

More information

Learn more about leukemia from the Leukemia & Lymphoma Society.

SOURCES: Michael Cleary, M.D., professor, pathology and pediatrics, Stanford University, Palo Alto, Calif.; Deborah Banker, Ph.D., vice president, research communication, Leukemia & Lymphoma Society, White Plains, N.Y.; Oct. 21, 2005, Cell

Last Updated: Oct. 21, 2005