Lung Cancer Protein Expression Profiles of Smokers and Non-Smokers

Epidemiological studies have established a causal relationship between cigarette smoking and respiratory tract cancer. The knowledge about the interaction of tobacco constituents with cellular systems is, however, still incomplete. Therefore, we analyzed 36 factors with known or assumed relevance and found that 8 proteins in lung cancer were associated with the smoking habits of 94 patients. These 8 factors belong to different functional classes including products of drug resistance-related proteins (P-glycoprotein, glutathione S-transferase-π, lung resistance protein, catalase), proto-oncogenes and transcription factors (FOS, JUN, HIF-1β), and proliferative factors (cyclin D). By means of hierarchical cluster analysis, we were able to show that the 94 patients analyzed could be separated into three different clusters, of which one contained significantly more patients who smoked than the others (p=0.0026). This cluster also contained significantly more drug-resistant tumors than the others (p=0.0069), pointing to a close interrelationship between the smoking habits of patients and drug resistance of tumors.