Fig. 1.

Effect of naproxen on spontaneous lung tumor development in a Kras^G12V mouse model.

(A) Gross morphology of the lungs from wild-type mice and lungs with tumors in Kras^G12V mice. Representative photomicrograph of hematoxylin and eosin-stained lung sections from mice belonging to control and naproxen treatment groups (magnification 10X; inset shows 60X magnification). Note the reduction in tumor size upon treatment. (B) Experimental design for evaluating the chemopreventive effect of dietary naproxen 400 ppm in a Kras^G12V lung cancer mouse model. Three to 4 wk-old Kras^G12V mice were weaned, genotyped, and randomized. At 6 wk of age, mice were shifted onto experimental diets containing naproxen (0 ppm or 400 ppm) for 30 wk until the end of the study. At 36 wk of age, mice were euthanized and lungs were harvested for evaluation of tumors. (C) Effect of naproxen (400 ppm) on number of (i) Lung tumors, (ii) Lung adenomas, and (iii) Lung adenocarcinomas (bottom). Data represent Mean ± SEM. Differences between groups were analyzed by unpaired student's t test with Welch's Correction.