Immunohistochemical and molecular assessment of human herpesvirus type 8 in gastrointestinal tumours.
BACKGROUND
Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal tumours of the gastrointestinal tract, histologically identified as highly cellular spindle or epithelioid cell tumours, and often positive for CD34 (60-70%). Kaposi's sarcomas (KSs) are similar to GISTs: they are most often found in the gastrointestinal tract (although cutaneous lesions do occur), they are also composed of spindle or epithelioid cells (although erythrocytes are also seen), and the tumour cells are nearly all positive for CD34. Human herpesvirus type 8 (HHV-8) DNA has been found consistently in all types of KS, in particular in CD34 positive KS tumour cells. However, the association between HHV-8 and GIST has not been investigated.


OBJECTIVE
To assess the presence of HHV-8 in GISTs.


METHODS
Paraffin wax embedded tissues of 86 primary GISTs and their recurrent or metastatic tumours were analysed immunohistochemically for the CD34 antigen and HHV-8 latent nuclear antigen 1 (LNA-1) and by means of the nested polymerase chain reaction (PCR) and real time PCR for HHV-8 DNA.


RESULTS
None of the 86 GISTs contained HHV-8 DNA sequences or LNA-1 positive cells.


CONCLUSIONS
These results demonstrate the lack of HHV-8 infection in GIST tumour cells. HHV-8 does not appear to play a role in the pathogenesis of GIST, irrespective of the status of the tumour.
Su
C C
CC
Department of Pathology, Buddhist Dalin Tzu Chi General Hospital, Dalin Town, Chiayi County 622, Taiwan. sucpo@yahoo.com.tw
Li
C F
CF
Liao
Y L
YL
Lin
C N
CN
Lu
J J
JJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018952:Antigens, CD34 / Q000032:analysis; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D046152:Gastrointestinal Stromal Tumors / Q000473:pathology / Q000556:secondary / Q000821:virology*; D019288:Herpesvirus 8, Human / Q000302:isolation & purification*; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins / Q000032:analysis; D016612:Paraffin Embedding; D010750:Phosphoproteins / Q000032:analysis; D016133:Polymerase Chain Reaction / Q000379:methods; D012189:Retrospective Studies
D018952:Antigens, CD34; D004279:DNA, Viral; D009687:Nuclear Proteins; D010750:Phosphoproteins; C118485:latent nuclear antigen (LNA)