Tuberculosis and lung cancer

To describe the epidemiological studies about the relationship between lung cancer (LC) and pulmonary tuberculosis (Tb) and its possible molecular mechanisms. We reviewed research databases in search of publications that included keywords LC and Tb. It has been proposed that chronic inflammation in the lungs due to Tb could cause clastogenic activity in the DNA of bronchial epithelium. Another possibility is lateral gene transfer; since Mycobacterium tuberculosis (MTb) is an intracellular organism, bacterial DNA could integrate to bronchial epithelial cells inducing neoplastic transformation. There are epidemiological reports, particularly from Asian countries, which confirm a relationship between LC and Tb. MTb could play an active role in cellular transformation and it is important to elucidate the mecha- nism involved.