Role of NOX2-Derived Reactive Oxygen Species in NK Cell-Mediated Control of Murine Melanoma Metastasis

• The NADPH oxidase of myeloid cells, NOX2, generates reactive oxygen species (ROS) to eliminate pathogens and malignant cells. NOX2-derived ROS have also been proposed to dampen functions of natural killer (NK) cells and other antineoplastic lymphocytes in the microenvironment of established tumors. The mechanisms by which NOX2 and ROS influence the process of distant metastasis have only been partially explored. Here, we utilized genetically NOX2-deficient mice and pharmacologic inhibition of NOX2 to elucidate the role of NOX2 for the hematogenous metastasis of melanoma cells. After intravenous inoculation of B16F1 or B16F10 cells, lung metastasis formation was reduced in B6.129S6 Cybb(m1DinK) (Nox2-KO) versus Nox2-sufficient wild-type (WT) mice. Systemic treatment with the NOX2-inhibitor histamine dihydrochloride (HDC) reduced melanoma metastasis and enhanced the infiltration of IFN gamma-producing NK cells into lungs of WT but not of Nox2-KO mice. IFN gamma-deficient B6.129S7-Ifngt(m1Ts)/ J mice were prone to develop melanoma metastases and did not respond to in vivo treatment with HDC. We propose that NOX2-derived ROS facilitate metastasis of melanoma cells by downmodulating NK-cell function and that inhibition of NOX2 may restore IFN gamma-dependent, NK cell-mediated clearance of melanoma cells.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Cancer och onkologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Cancer and Oncology (hsv//eng)

Keyword

neutrophil nadph oxidase

acute myeloid-leukemia

tumor-cells

respiratory burst

hydrogen-peroxide

interferon-gamma

dendritic cells

b16 melanoma

cancer

histamine

Oncology

Immunology

Publication and Content Type

ref (subject category)

art (subject category)