M.W. Roomi, N.W. Roomi, T. Kalinovsky, M. Rath and A. Niedzwiecki

Tumori 2009; 95(4): 508-513

Abstract:
Lung cancer, a leading cause of cancer death, is associated with exposure to inhalation carcinogens, most commonly those found in tobacco smoke. We investigated the in vivo effect of dietary supplementation with a nutrient mixture containing lysine, proline, ascorbic acid and green tea extract (NM) on the development of urethane-induced lung tumors in male A/J mice.

After one week of isolation, seven-week old male A/J mice (n=25) weighing 17-19 g, were randomly divided into three groups: Group A (n=5), Group B (n=10), and Group C (n=10). Mice in groups B and C were each given a single intraperitoneal injection of urethane (1 mg/g body weight) in saline, while Group A mice received an injection of saline alone. Groups A and B were fed a regular diet, while Group C was fed the same diet supplemented with 0.5% NM. After 20 weeks, mice were sacrificed, lungs were excised and weighed, and tumors were counted and processed for histology. Mice in urethane-challenged mice developed tumors; however, the mean number of tumors and the mean lung weights in the supplemented mice were significantly reduced, by 49% (p<0.0001) and 18% (p=0.0025) respectively, to mice on the control diet. Pulmonary lesions were morphologically similar for both the groups (adenomas) but lesions were smaller in the test group. These results suggest that NM has inhibitory potential on the development of mouse lung tumors induced by urethane.

Key words: 
A/J mice, nutrient mixture, primary lung tumors, urethane

The full study is available online at:
http://www.tumorionline.it/articoli.php?archivio=yes&vol_id=445&id=5260