Study shows how dioxin disrupts cells

PHILADELPHIA, Dec. 18 (UPI) -- U.S. scientists have determined the process by which the chemical dioxin attacks the body's cells and promotes tumor growth.

University of Pennsylvania School of Veterinary Medicine researchers determined that mitochondria -- the cellular sub-units that convert oxygen and nutrients into cellular fuel -- are targeted by tetrachlorodibenzodioxin, or TCDD, the most toxic compound in the dioxin family.

The study showed TCDD induces mitochondria-to-nucleus stress signaling, which in turn induces the expression of cell nucleus genes associated with tumor promotion and metastasis.

The scientists said their findings are directly relevant to understanding cancers in human populations exposed to such chemicals.

"Now that we have identified this signaling mechanism, we can look at ways to disrupt this complex chain of events," said Narayah Avadhani, the study's lead investigator. "Our ultimate goal is to block the propagation of this mitochondrial stress signaling and inhibit the expression of the proteins that combine to assist cancer growth."

The study that included researchers Gopa Biswas, Satish Srinivasan and Hindupur Anandatheerthavarada appears online and in the print issue of the Proceedings of the National Academy of Sciences.