Molecular Basis Of Genetic Susceptibility To Esophageal Cancer

Esophageal Cancer(EC) is a very common disease in many areas of China. The reported mortality rates in North China are the highest in the world. A nationwide survey of mortality identified EC as the second most common cause of cancer death in China.Over the past two decades, many studies have been conducted on the etiologic factors associated with EC. Our previous work had demonstrated that EC patients and their blood-relatives showed genetic instability and DNA repair defects caused by N-nitroso-compounds and other genotoxic agents. Surveys in high EC areas suggested that many of EC patients had family history and some autosomal recessive (and even dominant) genes might play an important role in the EC pathogenesis.Epidemiologic studies in China have implicated environmental factors in the etiology of EC. One of the main factors is the exposure of the inhabitants living in these areas to high level nitroso-compounds. N-nitroso-compounds are alkylating agents that can produce various alkyladducts in DNA and induce tumors directly in experimental animals. Among those. O~6-alklguanine appears to be primarily...