Resistance to cytarabine induces the up-regulation of NKG2D ligands and enhances natural killer cell lysis of leukemic cells

Prolonged treatment of leukemic cells with chemotherapeutic agents frequently results in development of drug resistance. Moreover, selection of drug-resistant cell populations may be associated with changes in malignant properties such as proliferation rate, invasiveness, and immunogenicity. In the present study, the sensitivity of cytarabine (1-beta-D-arabinofuranosylcytosine, araC)-resistant and parental human leukemic cell lines (T-lymphoid H9 and acute T-lymphoblastic leukemia Molt-4) to natural killer (NK) cell-mediated killing was investigated. The results obtained demonstrate that araC-resistant H9 and Molt-4 (H9(r)ARAC(100) and Molt-4(r)ARAC(100)) cell lines are more sensitive to NK cell-mediated lysis than their respective parental cell lines. This increased sensitivity was associated with a higher surface expression of ligands for the NK cell-activating receptor NKG2D, notably UL16 binding protein-2 (ULBP-2) and ULBP-3 in H9(r)ARAC(100) and Molt-4(r)ARAC(100) cell lines. Blocking ULBP-2 and ULBP-3 or NKG2D with monoclonal antibody completely abrogated NK cell lysis. Constitutive phosphorylated extracellular signal-regulated kinase (ERK) but not pAKT was higher in araC-resistant cells than in parental cell lines. Inhibition of ERK using ERK inhibitor PD98059 decreased both ULBP-2/ULBP-3 expression and NK cell cytotoxicity. Furthermore, overexpression of constitutively active ERK in H9 parental cells resulted in increased ULBP-2/ULBP-3 expression and enhanced NK cell lysis. These results demonstrate that increased sensitivity of araC-resistant leukemic cells to NK cell lysis is caused by higher NKG2D ligand expression, resulting from more active ERK signaling pathway.

Medienart:

E-Artikel

Erscheinungsjahr:

2008

Erschienen:

2008

Enthalten in:

Zur Gesamtaufnahme - volume:10

Enthalten in:

Neoplasia (New York, N.Y.) - 10(2008), 12 vom: 01. Dez., Seite 1402-10

Sprache:

Englisch

Beteiligte Personen:

Ogbomo, Henry [VerfasserIn]
Michaelis, Martin [VerfasserIn]
Klassert, Denise [VerfasserIn]
Doerr, Hans Wilhelm [VerfasserIn]
Cinatl, Jindrich [VerfasserIn]

Themen:

04079A1RDZ
82115-62-6
Antimetabolites, Antineoplastic
Cytarabine
EC 2.7.11.24
Extracellular Signal-Regulated MAP Kinases
Interferon-gamma
Journal Article
KLRK1 protein, human
Ligands
NK Cell Lectin-Like Receptor Subfamily K
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 24.04.2009

Date Revised 20.10.2021

published: Print

Citation Status MEDLINE

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM184856094