PPARα activation can help prevent and treat non-small cell lung cancer

Non-small cell lung cancer (NSCLC) not amenable to surgical resection has a high mortality rate, due to the ineffectiveness and toxicity of chemotherapy. Thus, there remains an urgent need of efficacious drugs that can combat this disease. In this study, we show that targeting the formation of proangiogenic epoxyeicosatrienoic acids (EET) by the cytochrome P450 arachidonic acid epoxygenases (Cyp2c) represents a new and safe mechanism to treat NSCLC growth and progression. In the transgenic murine K-Ras model and human orthotopic models of NSCLC, we found that Cyp2c44 could be downregulated by activating the transcription factor PPARa with the ligands bezafibrate and Wyeth-14,643. Notably, both treatments reduced primary and metastatic NSCLC growth, tumor angiogenesis, endothelial Cyp2c44 expression, and circulating EET levels. These beneficial effects were independent of the time of administration, whether before or after the onset of primary NSCLC, and they persisted after drug withdrawal, suggesting the benefits were durable. Our findings suggest that strategies to downregulate Cyp2c expression and/or its enzymatic activity may provide a safer and effective strategy to treat NSCLC. Moreover, as bezafibrate is a well-tolerated clinically approved drug used for managing lipidemia, our findings provide an immediate cue for clinical studies to evaluate the utility of PPARa ligands as safe agents for the treatment of lung cancer in humans.