In collaboration with colleagues at Cornell University, a team of cancer researchers at Cold Spring Harbor Laboratory (CSHL) has discovered cells with stem-cell properties in the ovary that can mutate to form tumors.
The team demonstrated that when two important tumor suppressor genes are inactivated, a previously unknown subset of ovarian stem-like epithelial cells undergoes cancerous transformation. The findings, published today in the journal Nature, have important implications for our knowledge about ovarian cancer.
"Sources of cells that make ovarian tumors are not really known," says Grigori Enikolopov, Ph.D., one of the co-authors and team leader at CSHL. Dr. Alexander Nikitin is the corresponding author and team leader at Cornel University. "We demonstrated that a stem cell population sits in a portion of the ovary called the hilum, and can repair the ruptures of the ovarian tissue during ovulation, and that these cells are easily transformed into tumor cells," Enikolopov explains.
The idea that cells with stem cell properties can spontaneously mutate to become seeds of cancer has been gaining momentum. Some epithelial cancers such as cancers of the ovary and the intestine are known to originate in the transition regions between different types of epithelial cells, but the exact source of such cells in the ovary has not been defined. Previous findings have suggested that cells in these transition regions may be more "plastic" and exist in a less mature (i.e., less "differentiated") state, making them potential candidates as a cancer source. Until now, however, the lack of direct experimental evidence has made this hypothesis difficult to confirm.