DNA methylation in pulmonary fibrosis and lung cancer.

INTRODUCTION: Pulmonary fibrosis is an age-related, progressive, and fatal disease with a median survival of 3-5 years after diagnosis; idiopathic pulmonary fibrosis (IPF) is the most common type. It is characterized by fibroblast proliferation and accumulation of excessive extracellular matrix. Patients with IPF are at increased risk for lung cancer. Epigenetic mechanisms are involved in lung fibrosis and cancer, and DNA methylation is critical in disease pathogenesis and progression. Therefore, studies of DNA methylation contribute to better understanding of the underlying mechanisms of these two respiratory diseases, and can offer novel diagnostic and treatment options. AREAS COVERED: This review discusses the latest advances in our understanding of epigenetic factors related to DNA methylation that impact development of lung cancer and pulmonary fibrosis, discusses the role of DNA methylation in promoting or inhibiting these diseases, and proposes its potential clinical significance in disease diagnosis and treatment. EXPERT OPINION: DNA methylation plays a critical role in lung cancer and fibrosis pathogenesis. DNA methylation offers a new biomarker for disease diagnosis or monitoring, and provides a new therapeutic target for treatment.