Analysis ofp53 Mutations in Liver Cancer Patients

Analysis ofp53 Mutations in Liver Cancer Patients 

Hepatocellular cancer (HCC) is a common cause of cancer death worldwide with a striking geographical variation in incidence. In the People s Republic of China, HCC has an incidence rate of 150 cases per 100,000 per year in some regions and accounts for over 250,000 deaths annually. Major etiological factors associated with development of HCC include iufection with hepatitis B or C viruses and exposure to dietaryaflatoxin Bi (AFBi) [26 27]. 

A specific mutation in the p53 tumour suppressor gene has been detected in 10-70% of HCCs from areas of high AFBi exposure and is absent from HCCs from areas with negligible AFBi exposure [28-30]. Support for the implication that the mutation, a G- T transversion at the third base of codon 249, is caused by exposure to aflatoxin has come from in vitro studies. Aflatoxin exposure in bacteria almost exclusively causes G—transversions [31] and the aflatoxin-epoxide has been shown to bind to codon 249 of p53 in vitro [32]. Moreover, human 

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