Study links stem cells to bone cancer

The cancer stem cell theory holds that a small subpopulation of rogue stem cells exists within a tumor and has the ability to sustain itself. As these abnormal cells divide, they may generate the bulk of a malignant tumor, then help to spur on its growth. A problem exists in treating these cells as most chemotherapeutic regimens work against the bulk tumor and may be ineffectual against the small number of malignant stem cells.

The researchers studied two types of tumors, osteosarcomas common in childhood and adolescence, and chondrosarcomas, a form of adult bone cancer that requires aggressive surgery to treat because it does not respond to chemotherapy or radiation.

Using specialized cell culture techniques, they were able to isolate stem-like cells from bone tumors. About one in 1,000 cells in the samples they studied had features of embryonic stem cells. The researchers also found abundant levels in their samples of the two key factors that help maintain embryonic stem cells in a very primitive state.

“We’re saying the cell of origin of these tumors may be very, very primitive,” said Dr Parker Gibbs, an associate professor of orthopaedic oncology and a member of the University of Florida Shands Cancer Center.

“The existence of stem-like cells in bone sarcomas suggests that the study of stem cell biology may provide opportunities for targeted therapies that are markedly less toxic than current aggressive chemotherapy and surgical protocols,” Dr Gibbs added.