New anti-cancer control mechanism found

MONTREAL, -- Canadian medical researchers say they have dis-
covered a new anti-cancer, anti-infection response control
mechanism. Dr. Andre Veillette of the Institute of Research
Clinics in Montreal, and his team led by postdoctoral fellow
Dr. Mario-Ernesto Cruz-Munoz, said their discovery could have
a significant impact on the treatment of cancers and infec-
tious diseases. The team identified one of the basic mechan-
isms controlling "natural killer" cell activity. Produced by
the immune system, NK cells are responsible for recognizing
and killing cancer cells and cells infected by viruses, they
said, and NK cell deficiency is associated with a higher
incidence of cancers and serious infections. "Our break-
through demonstrates that a molecule known as CRACC, which is
present at the surface of NK cells, increases their killer
function," said Veillette. Using mice, the researchers showed
those lacking the CRACC gene were found to be more suscept-
ible to cancer persistence. Conversely, stimulation of CRACC
function was found to improve cancer cell elimination. Thus,
they said, stimulating CRACC could boost NK cell activity,
helping to fight cancers. In addition, it could improve the
ability to fight infections, which are also handled by NK
cells. The findings are detailed in the journal Nature
Immunology.