New way created to study cancer stem cells

PITTSBURGH, June 7 (UPI) -- U.S. scientists say they've found a way of preventing isolated cancer stem cells from differentiating into other types of tumor-forming cells.

Researchers at the Children's Hospital of Pittsburgh and the University of Pittsburgh School of Medicine said their discovery will allow researchers to further study and characterize cancer stem cells, as well as screen drugs that could specifically target them.

Dr. Edward Prochownik, a professor at the medical school who led the study, said he and his team focused on four different lines of breast cancer stem cells.

Although they make up a relatively small portion of a tumor, cancer stem cells are believed to initiate and sustain tumors as they grow and metastasize. They also differentiate into other cells within three to five weeks of being isolated, making them difficult to study, Prochownik said.

He and his colleagues said they were able to tag the breast cancer stem cells they isolated with green fluorescent protein and a stem cell-specific promoter know as Oct3/4.

"Using this approach, we can essentially freeze the stem cells in their current state, grow them in unlimited quantities and then … use existing technology to screen them for chemotherapy agents and other therapies to determine which therapies are most effective at destroying the cancer stem cells," Prochownik said.

The research appears in the June issue of the journal Stem Cells.