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Research Corner

Tumor 'stem-like cells' found in benign tumors

Research scientists at Cedars-Sinai's Maxine Dunitz Neurosurgical Institute have isolated stem-like cells in benign pituitary tumors and used these "mother" cells to generate new tumors in laboratory mice. Targeting the cells of origin is seen as a possible strategy in the fight against malignant and benign tumors.

When tumor stem-like cells were implanted into laboratory mice, they generated new tumors that had the same genetic composition and characteristics as the original tumors, according to an article in the July 2009 issue of the British Journal of Cancer. Cells from the new tumors, later transplanted into other mice, maintained the same tumor-specific properties.

"Although previous studies have offered evidence of the existence of stem-like cells in pituitary adenomas (benign tumors), in this study we scrutinized these cells for composition and function, demonstrating that stem-like cells exist in benign tumors," said John S. Yu, M.D., director of Surgical Neuro-oncology at Cedars-Sinai and senior author of the journal article.

Although pituitary adenomas are typically noncancerous, the tumors can cause significant injury or illness by compressing important structures or creating hormone imbalances. Identifying the mechanisms that enable these and other tumors to form may provide unique targets for new, more effective therapies.

"It appears that stem cells from different cancers - or possibly even within the same tumor - may use different signaling pathways and have different implications for disease progression and prognosis," said Keith L. Black, M.D., chair of the Department of Neurosurgery. "Findings from the pituitary tumor study generally support the cancer stem cell hypothesis, suggesting that similar mechanisms may be involved in the generation of both malignant and benign tumors."