Anti-inflammatory prevents pancreatic cancer in mice.

An inflammation-fighting drug limits premalignant lesions in mice prone to getting pancreatie cancer. The new finding suggests that this drug or related ones might prevent pancreatic cancer in people who face an elevated risk of developing it. Risk factors include smoking or having a relative with the disease.

Pancreatic-cancer cells often harbor a mutation in a gene called Kras. In mice genetically engineered to carry this mutation in their pancreas tissues, the pancreatic ducts develop precancerous lesions and, by age 12 to 15 months, cancer.

Past research had implicated the inflammation-causing enzyme cyclooxygenase-2 (COX-2) in a chain of biological events leading to abnormal cell growth and cancer in other organs (SN: 4/10/04, p. 230; 8/18/01, p. 109).

To test whether thwarting COX-2 would have an effect on mice predisposed to pancreatic cancer, the researchers fed chow containing a COX-2 inhibitor called nimesulide to mice harboring the Kras mutation. A group of similar mice received chow without the COX-2 inhibitor.

At 10 months, none of the ducts in mice treated with nimesulide had developed dangerous precancerous lesions, whereas 10 percent of the pancreatic ducts in mice not getting the drug had such lesions, the scientists report in the Aug. 1 Cancer Research.

"This shows that COX-2 is a very important molecule in the progression of pancreatic cancer, and inhibiting it can delay or prevent cancer, says Guido Eibl, a surgeon at the University of California, Los Angeles.

However, COX-2 inhibitors have been linked to a heightened risk of heart problems (SN: 10/30/04, p. 286). If they prove too chancy to give to people as a cancer preventive, Eibl says, scientists can test other drugs that affect the events that lead to abnormal growth and cancer.