Investigation of Epstein-Barr virus in Chinese colorectal tumors.
OBJECTIVE
To elucidate the association of Epstein-Barr virus (EBV) with colorectal tumors and to demonstrate whether infection of EBV existed in different stages of colorectal tumors involves in the carcinogenesis.


METHODS
One hundred and thirty paraffin-embedded tissues of colorectal tumors were classified into 5 groups: 26 adenomas, 23 adenomas complicated with dysplasia, 22 adenomas complicated with carcinomatous, 36 colon carcinoma and 23 HNPCC, were examined by PCR, IHC and ISH, respectively.


RESULTS
EBV DNA was detected by PCR in 26 cases out of the 130 specimens, including 5 cases of adenomas, 5 adenomas complicated with dysplasia, 5 adenomas complicated with carcinomatous, 7 colorectal carcinoma and 4 HNPCC. IHC detection showed the expression of LMP1 in 7 cases, including 1 adenoma, 1 adenoma with dysplasia, 1 HNPPC, 2 adenomas complicated with carcinomatous, and 2 colorectal carcinomas. The expression of EBER1 detected by ISH was positive in 6 cases, including 1 adenoma with dysplasia, 2 adenomas complicated with carcinomatous and 3 colorectal carcinomas. There were no significant differences among the results of PCR, IHC and ISH in the 5 groups. In all cases of HNPCC, none of the tumor cells showed positive signals of EBER1, but some EBV-positive tumor infiltrating lymphocytes were found in 2 of 23 cases.


CONCLUSIONS
Our results showed that infection of EBV exists in human colorectal tumors, which indicates that EBV may be involved in the carcinogenesis of colorectal tumors but does not play an important role. The mechanisms need to be clarified further.
Liu
Huan-Xin
HX
Department of Pathology, the First Military Medical University, Guangzhou 510515, Guangdong Province, China.
Ding
Yan-Qing
YQ
Li
Xin
X
Yao
Kai-Tai
KT
D000236:Adenoma / Q000821:virology*; D044466:Asian People; D015179:Colorectal Neoplasms / Q000821:virology*; D004279:DNA, Viral / Q000032:analysis; D020031:Epstein-Barr Virus Infections / Q000150:complications* / Q000175:diagnosis*; D004854:Herpesvirus 4, Human / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D017403:In Situ Hybridization
D004279:DNA, Viral