FRIDAY, July 8 (HealthDay News) -- Celecoxib significantly reduces bronchial Ki-67 labeling index (Ki-67 LI), and may be a potential chemopreventive agent for lung cancer in former smokers, according to a study published in the July issue of Cancer Prevention Research.
Jenny T. Mao, M.D., from the University of New Mexico in Albuquerque, and colleagues investigated the impact of celecoxib on cellular and molecular events associated with lung cancer pathogenesis in 137 ex-smokers (45 years or older) who had smoked 30 or more pack-years, who had achieved continued abstinence for one or more years. The participants were randomly assigned to receive either 400 mg celecoxib twice daily for six months or placebo, and then the treatment groups were crossed over at six months. Chest computed tomography (CT) scans were conducted at baseline and 12 months. Ki-67 LI after six months of treatment was the main outcome measured in bronchoscopies of 101 participants.
The investigators found that the celecoxib group experienced a significant decrease of 34 percent in Ki-67 LI compared to the placebo group, which experienced a Ki-67 LI increase of 3.8 percent. A significant reduction in plasma C-reactive protein, interleukin-6 mRNA and protein, and an increase in 15(S)-hydroxy-eicosatetraenoic acid levels were seen in bronchoalveolar lavage (BAL) samples in the celecoxib group. At 12 months, CT showed that the decrease in Ki-67 LI at six months was associated with a reduction or resolution of lung nodules. The BAL-cell baseline ratio of COX-2 to 15-hydroxyprostaglandin dehydrogenase mRNA was a significant predictive marker of the Ki-67 LI response to celecoxib.
"Six months of celecoxib significantly reduced Ki-67 LI and favorably modulated a variety of secondary end points," the authors write.
One author disclosed a financial relationship with Tragara Pharmaceuticals. The study drugs and plasma celecoxib measurements were provided by Pfizer Inc.