The findings, conducted in cell culture and in mice and reported
by the researchers in the January issue of Molecular
Endocrinology, could help explain why women who have mutations
in their BRCA1 gene are susceptible to a number of different
"hormone-dependent" cancers, including those of the breast,
endometriun and cervix. It also has implications for ordinary
cancers that arise because a normal BRCA1 gene is under-
expressed, said the study's principal investigator, Eliot Rosen,
MD, PhD, professor of oncology, cell biology, and radiation
medicine at the Lombardi Comprehensive Cancer Center. For
example, he says that up to 40 percent of breast tumors are
deficient in BRCA1, "and it may be that some patients could
benefit not only from an anti-estrogen therapy, like tamoxifen,
but also from an anti-progesterone agent. "We don't know if that
is true yet, of course, but it is certainly worth investigating,
given our findings," Rosen said. The BRCA1 gene and a second
gene, BRCA2, were discovered to be breast canc