Research
July 22, 2011
Progesterone foils cancer cell growth
Donald Stein
Emory researchers have found a promising weapon in the fight against neuroblastoma, the most common form of cancer affecting small children.
High doses of the hormone progesterone can kill neuroblastoma cells while leaving healthy cells unscathed, School of Medicine scientists found in laboratory research.
More research is needed to determine the optimal dose, how long progesterone treatment should last and if it should be used alone or in combination with radiation or chemotherapy.
Emory scientists are also exploring whether it can stop the growth of other brain cancer types such as glioblastoma and astrocytoma.
The discovery grew out of studies of progesterone's protective effects in brain injury. Donald Stein, Asa G. Candler professor of emergency medicine and director of Emory's Department of Emergency Medicine Brain Research Laboratory; Fahim Atif, instructor in emergency medicine at Emory; and Daniel Brat, professor of pathology and laboratory medicine in the School of Medicine collaborated on the study, which was supported by grant from Allen and Company.
Based on the pioneering work of Stein, medical centers across the country are now testing progesterone in a phase III clinical trial for acute traumatic brain injury. While investigating how to enhance progesterone's effectiveness, Atif and his colleagues observed that it could protect healthy neurons from stress but caused cells from a tumor cell line to die.
In a mouse model, progesterone treatment cut tumor growth in half over eight days. No drug toxicity was observed.
The researchers showed that progesterone can foil the way tumor cells invade other tissues.
"This fits with what we know about one of progesterone's roles during pregnancy, which is to regulate the growth of placenta," Atif says. "Placental cells behave in a way that resembles tumor cells, invading the uterine wall and tapping into the mother's blood vessels."
In studies performed elsewhere, doses of progesterone that were lower than the most effective dose in the Emory study actually accelerated cancer growth. Based on their results, the Emory researchers propose that for fighting certain types of cancer, high doses of progesterone may be better than low doses.
The work is part of Campaign Emory, the University's $1.6 billion comprehensive fundraising campaign.
