A high concentration of MMP-2/gelatinase A and MMP-9/gelatinase B reduce NK cell-mediated cytotoxicity against an oral squamous cell carcinoma cell line.
BACKGROUND
Recent studies have shown that matrix metalloproteinases (MMPs) from tumors influence the host immune system to reduce antitumor activity. The aim of this study was to examine the influence of MMP-2 and MMP-9 on the natural killer (NK) cell.


METHODS
NK cells were pretreated with either MMP-2 or MMP-9 in the experimental group but not in the control group. NK cell cytotoxicity against oral squamous cell carcinoma cells (OSCC) were examined using the [Cr51] release assay and the expression levels of surface receptors on NK cells were measured by flow cytometry.


RESULTS
NK cell cytotoxicity was significantly reduced in the experimental group compared to the control group. Significant increases in KIR expression and decreases in NKG2D expression on the NK cells were observed in the experimental group.


CONCLUSIONS
This study suggests an additional role of MMP-2 and MMP-9 in an immune escape mechanism of OSCC.
Department of Oral and Maxillofacial Surgery, Asan Institute for Life Sciences, Asan Medical Center, College of Medicine, Ulsan University, Songpa-ku, 138-040, Seoul. bukyu67@yahoo.co.kr
Bu-Kyu
BK
Lee
Mi-Jung
MJ
Kim
Ha-Soon
HS
Jang
Hee-Ran
HR
Lee
Kang-Min
KM
Ahn
Jong-Ho
JH
Lee
Pill-Hoon
PH
Choung
Myung-Jin
MJ
Kim
D002294:Carcinoma, Squamous Cell / Q000201:enzymology / Q000276:immunology / Q000473:pathology*; D045744:Cell Line, Tumor; D003602:Cytotoxicity, Immunologic; D005434:Flow Cytometry; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology*; D020778:Matrix Metalloproteinase 2 / Q000097:blood*; D020780:Matrix Metalloproteinase 9 / Q000097:blood*; D009062:Mouth Neoplasms / Q000201:enzymology / Q000276:immunology / Q000473:pathology*
C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9