Expression of CD86 and increased infiltration of NK cells are associated with Helicobacter pylori-dependent state of early stage high-grade gastric MALT lymphoma.
OBJECTIVE
A high percentage of early-stage high-grade gastric mucosa-associated lymphoid tissue (MALT) lymphomas remain Helicobacter pylori (H pylori)-dependent. However, unlike their low-grade counterparts, high-grade gastric MALT lymphomas may progress rapidly if unresponsive to H pylori eradication. It is mandatory to identify markers that may predict the H pylori-dependent status of these tumors. Proliferation of MALT lymphoma cells depends on cognate help and cell-to-cell contact of H pylori-specific intratumoral T-cells. To examine whether the expression of co-stimulatory marker CD86 (B7.2) and the infiltration of CD56 (+) natural killer (NK) cells can be useful markers to predict H pylori-dependent status of high-grade gastric MALT lymphoma.


METHODS
Lymphoma biopsies from 26 patients who had participated in a prospective study of H pylori-eradication for stage I(E) high-grade gastric MALT lymphomas were evaluated. Tumors that resolved to Wotherspoon grade II or less after H pylori eradication were classified as H pylori-dependent; others were classified as H pylori-independent. The infiltration of NK cells and the expression of CD86 in pre-treatment paraffin-embedded lymphoma tissues were determined by immunohistochemistry.


RESULTS
There were 16 H pylori-dependent and 10 H pylori-independent cases. CD86 expression was detected in 11 (68.8%) of 16 H pylori-dependent cases but in none of 10 H pylori-independent cases (P = 0.001). H pylori-dependent high-grade gastric MALT lymphomas contained significantly higher numbers of CD56 (+) NK cells than H pylori-independent cases (2.8+/-1.4% vs 1.1+/-0.8%; P = 0.003). CD86 positive MALT lymphomas also showed significantly increased infiltration of CD56 (+) NK cells compared to CD86-negative cases (2.9+/-1.1% vs 1.4+/-1.3%; P = 0.005).


CONCLUSIONS
These results suggest that the expression of co-stimulatory marker CD86 and the increased infiltration of NK cells are associated with H pylori-dependent state of early-stage high-grade gastric MALT lymphomas.
Kuo
Sung-Hsin
SH
Department of Oncology, National Taiwan University Hospital, No. 7, Chung-Shan South Road, Taipei, Taiwan, China.
Chen
Li-Tzong
LT
Chen
Chi-Long
CL
Doong
Shin-Lian
SL
Yeh
Kun-Huei
KH
Wu
Ming-Shiang
MS
Mao
Tsui-Lien
TL
Hsu
Hui-Chen
HC
Wang
Hsiu-Po
HP
Lin
Jaw-Town
JT
Cheng
Ann-Lii
AL
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000378:metabolism*; D051940:B7-2 Antigen; D015415:Biomarkers / Q000378:metabolism; D005260:Female; D016481:Helicobacter Infections / Q000276:immunology* / Q000473:pathology; D016480:Helicobacter pylori; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology; D018442:Lymphoma, B-Cell, Marginal Zone / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism*; D008875:Middle Aged; D009367:Neoplasm Staging
D015703:Antigens, CD; D051940:B7-2 Antigen; D015415:Biomarkers; C497964:CD86 protein, human; D008562:Membrane Glycoproteins