EBV Conference 2008 Guangzhou - Baylor College of Medicine

195 (RegID: 1274; 1275)
Miki Takahara
Institution: Department of Otolaryngology-Head and Neck Surgery, Asahikawa Medical College
e-mail: miki@asahikawa-med.ac.jp
EXPRESSION AND FUNCTION OF LFA-1 AND ICAM-1 IN NASAL NK/T CELL LYMPHOMA
Miki Takahara, Kan Kishibe, Shigetaka Moriai, Hideyuki Ishii, and Yasuaki Harabuchi.
Posterabstract:
Nasal NK/T-cell lymphoma is characterized by progressive necrotic lesions with infiltrative tumor cells in
the nasal cavity. Prognosis of the lymphoma have very poor with progressive infiltration of lymphoma
cells in local lesion and/or distant metastasis. Therefore, it is necessary for the treatment of the lymphoma
to understand of the tumor characteristics. Previously we reported that the lymphoma cells are infected
with Epstein-Barr virus (EBV), and that EBV is related to pathogenesis of the lymphoma through
cytokines such as IL-9 and IL-10. However the characteristics were not fully understood.
It is known that cell adhesion molecules are related to progression of several kinds of malignancies.
However, in hematopoietic malignancies, especially nasal NK/T-cell lymphoma, role of the molecules
have not been examined in detail yet. LFA-1 (Leukocyte Function-associated Antigen-1) and its ligand,
ICAM-1 (Intercellular Adhesion Molecule-1), which are typical cell adhesion molecules, take important
role in attack of NK-cells to target cells. LFA-1 on NK-cells is combined with ICAM-1 on target cells, and
signals from LFA-1 enhance activation and proliferation of NK-cells for elevation of offensive power of
NK-cells. We examined the expression and function of the two molecules in EBV positive (SNK6) and
EBV negative (KHYG-1) cell line. Moreover, because we previously reported existence of soluble
ICAM-1 in serum form nasal NK/T-cell lymphoma, soluble ICAM-1 was also measured in culture
supernatant of SNK6 cells.
Flow cytometric analysis revealed that both LFA-1 and ICAM-1 were expressed on both SNK6 and
KHYG-1 cells. ELISA analysis revealed that soluble ICAM-1 was detected in culture supernatant of
SNK6 cells, but not in supernatant of KHYG-1. Moreover, MTS assay showed that proliferation potency
of the SNK6 cells decreased on culture in presence of LFA-1 blocking antibody. Therefore, combination
of LFA-1 and ICAM-1 enhanced proliferation potency of SNK6 cells.
EBV Conference 2008 Guangzhou
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