The Preliminary Research Of The Mutation And Expression Of Gene β-catenin In Human Hepatocellular Carcinoma Under Bi-Exposure Of Hepatitis B Virus And Aflatoxin B1, Guangxi, China

Objective:To explore the expression and mutation of β-catenin in HCC from the Guangxi province with hepatitis B virus (HBV) and high exposure level of aflatoxin B1(AFB1).Methods:108cases, from different areas of Guangxi province, were categorized into HBV(+)/AFB1(+)(experimental group A),48cases; HBV(+)/AFB1(-)(control group B),27cases; HBV(-)/AFB1(+)(control group C),15cases; and HBV(-)/AFB1(-)(control group D),14cases, according to the exposure condition of HBV and AFB1. And for normal controls,20cases of hepatic hemangioma liver resection and liver transplant donor hepatic tissue were selected, including HBV(-)/AFB1(+),10cases,and HBV (-)/AFB1(-),10cases. By means of PCR direct sequenced, reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC), the mutation of exon3of β-catenin and the expression condition of the protein were tested respectively.Results:(1) The total mutation rate of gene β-catenin in108HCC cases was11.1%,(12/108); the hot point of β-catenin mutation was codon37and codon41, occupied91.7%(11/12)of the total mutation rate; The positive rate of experimental group A, control group B, C and D was14.5%(7/48),3.7%(1/27),21.1%(4/19) and0%(0/14) respectively. The differences among all groups were not significant (P>0.05).(2) The mRNA level of β-catenin in group A, control group B, C, D and normal controls group was1.13±0.14,1.06±0.12,1.16±0.18,1.01±0.13,0.085±0.13respectively. Compared with group D, the mRNA level of group A and group C was higher (P<0.05).(3) The positive expression of β-catenin, the positive rate in108cases was70.0%(75/108), and the positive rate in experiment group A, control group B, C and D was70.8%(34/48)、66.6%(18/27)、78.9%(15/19) and57.1%(8/14) respectively. The differences among all groups were not significant (P>0.05).Conclusions:The mutation of β-catenin gene was11.1%in HCC patients from Guangxi province. And the hot point of β-catenin mutation was codon37and codon41. The reasons of over-expression of β-catenin were the mutation of β-catenin exon3and the high level of β-catenin mRNA. AFB1may play a important role in the mutation of β-catenin exon3and the high level of β-catenin mRNA.