Relationship between Epstein-Barr virus-encoded RNA expression, apoptosis and lymphocytic infiltration in gastric carcinoma with lymphoid-rich stroma.
OBJECTIVE
To investigate the association of apoptosis with apoptotic proteins and Epstein-Barr virus (EBV) expression in gastric carcinoma with lymphoid-rich stroma (GCLRS) in order to clarify the relationship between lymphocytic infiltration, EBV expression and apoptosis in gastric carcinoma.


METHODS
We performed immunohistochemical stains for bcl-2, bax and in situ hybridization for EBV-encoded RNA and the terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick end labeling technique using the 24 cases of GCLRS and 23 cases of gastric carcinoma with lymphoid-poor stroma (GCLPS) out of 1,635 cases of gastric carcinoma.


RESULTS
The prevalence of GCLRS was 1.47% (24/1,635). The prevalence of EBV involvement in GCLRS (79%, 19/24) was significantly higher than in GCLPS (8.7%, 2/23). Apoptosis was revealed in all cases and there was no statistical difference between GCLRS and GCLPS. Immunohistochemical expression for bcl-2 was revealed only in the cytoplasm of lymphocytes in all cases, but bax showed distinct expression in the cytoplasm of neoplastic cells in all cases. There was a significant correlation between bax expression and the apoptotic index (p <0.05). Lymphocytic infiltration was significantly correlated with the expression of EBV (p <0.05) but not with survival rate and apoptosis. Most of the GCLRS cases were rated as low clinical stage (stage IA or B) and seemed to have a good prognosis.


CONCLUSIONS
These results support the hypothesis that EBV infection plays an important role in the tumorigenesis of GCLRS, which has a better prognosis than usual gastric adenocarcinoma although there was no significant difference in the apoptotic index between GCLRS and GCLPS.
Cho
Mee-Yon
MY
Department of Pathology, Wonju College of Medicine, Yonsei University, Wonju, Korea.
Kim
Tae Heon
TH
Yi
Sang Yeop
SY
Jung
Woo Hee
WH
Park
Kwang Hwa
KH
D000230:Adenocarcinoma / Q000473:pathology / Q000821:virology*; D017209:Apoptosis; D016022:Case-Control Studies; D020031:Epstein-Barr Virus Infections / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D020287:In Situ Nick-End Labeling; D007723:Korea / Q000453:epidemiology; D016246:Lymphocytes, Tumor-Infiltrating / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D012367:RNA, Viral / Q000032:analysis*; D013194:Staining and Labeling; D013274:Stomach Neoplasms / Q000401:mortality / Q000473:pathology / Q000821:virology*
D019253:Proto-Oncogene Proteins c-bcl-2; D012367:RNA, Viral