Carboxyl-terminal sequence variation of latent membrane protein 1 gene in Epstein-Barr virus-associated gastric carcinomas from Eastern China and Japan.
OBJECTIVE
To elucidate variations of latent membrane protein 1 (LMP1) in Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) and explore the LMP1 variations of neighboring countries, China and Japan.


METHODS
In 12 and 8 EBVaGCs from eastern China and Japan, respectively, the C-termini of LMP1 were analyzed using PCR and sequencing. The sequences were compared with previously published strains and were characterized on a phylogenetic tree. The difference between Chinese and Japanese isolates was characterized.


RESULTS
Ten of 12 Chinese GC isolates (83.3%) and all of the 8 (100%) Japanese GC isolates belonged to the China 1 strain. Also, B95-8 type isolates were found in 2 of 12 Chinese GC. In the 18 China 1 type isolates, additional mutations outside the signature sequence changes were found. All Japanese isolates (100%) had two or more additional mutations, whereas only 5 of 10 (50%) Chinese isolates had two or more additional mutations. The difference was statistically significant (p = 0.0359).


CONCLUSIONS
China 1 is the dominant strain in GC from eastern China and Japan. The similarity to that of nasopharyngeal carcinoma (NPC) from China supports the view that China 1 strain represents a geographic-associated polymorphism rather than an NPC-associated polymorphism. Japanese isolates show more mutations than Chinese isolates, suggesting a geographic difference between Chinese and Japanese isolates in GC.
Wang
Yun
Y
Division of Biosignaling, Department of Biomedical Sciences, School of Life Science, Faculty of Medicine, Tottori University, Yonago, Japan.
Kanai
Kyosuke
K
Satoh
Yukio
Y
Luo
Bing
B
Sairenji
Takeshi
T
D002681:China; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D005838:Genotype; D004854:Herpesvirus 4, Human / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D007564:Japan; D017720:Molecular Epidemiology; D009154:Mutation; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D017434:Protein Structure, Tertiary / Q000235:genetics; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D013274:Stomach Neoplasms / Q000821:virology*; D014763:Viral Matrix Proteins / Q000235:genetics*
D004279:DNA, Viral; C037662:EBV-associated membrane antigen, Epstein-Barr virus; D014763:Viral Matrix Proteins