Effect of functional nuclear factor kappaB genetic polymorphisms on hepatitis B virus persistence and their interactions with viral mutations on the risk of hepatocellular carcinoma
Menée en Chine auprès de 3 976 cas et 1 342 témoins, cette étude évalue l'association entre des polymorphismes du gène NF-κB, la persistence d'une infection par le virus de l'hépatite B et le risque de carcinome hépatocellulaire
Résumé en anglais
Background: Non-resolving inflammation and viral mutations are important in hepatitis B virus (HBV)-induced hepatocarcinogenesis. However, the effects of genetic polymorphisms affecting nuclear factor kappaB (NF-κB) on HBV persistence and generation of hepatocellular carcinoma (HCC)-related HBV mutations remain unknown.
Patients and methods : rs28362491 (NFKB1 -94Ins>Del), rs2233406 (NFKBIA -826C>T), rs3138053 (NFKBIA -881A>G), and rs696 (NFKBIA +2758G>A) were genotyped in 1,342 healthy controls, 327 HBV-clearance subjects, and 3,976 HBV-positive subjects including 1,495 HCC patients, using quantitative PCR. HBV mutations were determined by sequencing. The NFKBIA promoter activity was assessed by transient transfection. Multiplicative interactions of the polymorphisms and viral mutations were assessed by multivariate logistic regression.
Results : Compared to HBV-clearance subjects, rs2233406 (CT versus CC) and rs3138053 (AG or AG+GG versus AA) significantly decreased HBV persistence, especially in the genotype B HBV-infected subjects. In the genotype C HBV-infected subjects, rs2233406 variant genotypes were significantly associated with an increased risk of HCC (CT versus CC: age-, gender-adjusted odds ratio [AOR], 1.33; 95% confidence interval [CI], 1.01-1.75 in training set and AOR, 1.59; 95% CI, 1.01-2.52 in validation set) compared to HCC-free HBV-infected subjects and significantly increased the frequencies of HCC-related HBV mutations (A1762T/G1764A, T1753 V, preS1 start codon mutation, and preS deletion); rs28362491 (Del/Del or Ins/Del+Del/Del versus Ins/Ins) significantly increased the frequency of A1762T/G1764A and reduced the frequency of preS2 start codon mutation. The variant genotypes impaired NFKBIA promoter activity in hepatic cells. The interaction of rs2233406 variant genotypes (CT+TT versue CC) with A1762T/G1764A significantly increased HCC risk in genotype C HBV-infected subjects, with AOR of 2.61 (95% CI, 1.09-6.26).
Conclusion : Genetic polymorphisms improving NF-κB activity contribute to genotype B HBV clearance. The rs2233406 variant genotypes significantly increase HCC risk, possibly via facilitating immune selection of the HBV mutations. The host-virus interactions are important in identifying HBV-infected subjects who are more likely to develop HCC.
