OBJECTIVES: To characterize the mutation pattern of a hepatitis B virus (HBV) core protein (HBcAg) derived from hepatocellular carcinoma (HCC) and adjacent nontumor tissues. METHODS: HBV core gene fragments (nt. 1901-2365) were amplified from 98 HBV-related HCC tissues and 33 adjacent nontumor tissues. The deduced amino acids (AAs) of the core gene were aligned with the prototype sequences of HBV genotypes B and C. RESULTS: In total, there were 54 positions that showed polymorphism at the deduced AA level. The mutations were predominantly located in three major (codons 83-87, 95-104 and 130-135) and three minor (codons 21-38, 59-63 and 151-155) mutation-clustering regions (MCRs). The substitution rate in MCRs was significantly higher than in mutation-devoid regions (p < 0.001). The most frequently occurring mutations in rank were codon P130T (38.8%), I97L (37.8%) and S87G (23.5%). In addition, there were 7 patients that showed internal deletions in the middle of HBcAg with sizes ranging from 34 to 59 AAs. Unexpectedly, the core genes isolated from tumor tissues had fewer mutations compared with those isolated from adjacent nontumor tissues from the same patients (p < 0.05). CONCLUSIONS: Accumulation of naturally occurring mutations in certain restricted segments of HBcAg may be related to the development of HCC.
OBJECTIVES: To characterize the mutation pattern of a hepatitis B virus (HBV) core protein (HBcAg) derived from hepatocellular carcinoma (HCC) and adjacent nontumor tissues. METHODS:HBV core gene fragments (nt. 1901-2365) were amplified from 98 HBV-related HCC tissues and 33 adjacent nontumor tissues. The deduced amino acids (AAs) of the core gene were aligned with the prototype sequences of HBV genotypes B and C. RESULTS: In total, there were 54 positions that showed polymorphism at the deduced AA level. The mutations were predominantly located in three major (codons 83-87, 95-104 and 130-135) and three minor (codons 21-38, 59-63 and 151-155) mutation-clustering regions (MCRs). The substitution rate in MCRs was significantly higher than in mutation-devoid regions (p < 0.001). The most frequently occurring mutations in rank were codon P130T (38.8%), I97L (37.8%) and S87G (23.5%). In addition, there were 7 patients that showed internal deletions in the middle of HBcAg with sizes ranging from 34 to 59 AAs. Unexpectedly, the core genes isolated from tumor tissues had fewer mutations compared with those isolated from adjacent nontumor tissues from the same patients (p < 0.05). CONCLUSIONS: Accumulation of naturally occurring mutations in certain restricted segments of HBcAg may be related to the development of HCC.
Authors: Ahmed A Al-Qahtani; Mashael R Al-Anazi; Nyla Nazir; Ayman A Abdo; Faisal M Sanai; Waleed K Al-Hamoudi; Khalid A Alswat; Hamad I Al-Ashgar; Mohammed Q Khan; Ali Albenmousa; Ahmed El-Shamy; Salah K Alanazi; Damian Dela Cruz; Marie Fe F Bohol; Mohammed N Al-Ahdal Journal: Front Cell Infect Microbiol Date: 2018-10-22 Impact factor: 5.293
Authors: Taoyang Chen; Gengsun Qian; Chunsun Fan; Yan Sun; Jinbing Wang; Peixin Lu; Xuefeng Xue; Yan Wu; Qinan Zhang; Yan Jin; Yiqian Wu; Yu Gan; Jianquan Lu; Thomas W Kensler; John D Groopman; Hong Tu Journal: Hepatoma Res Date: 2018-01-26