Due to their
chemoattractant properties stimulating the accumulation of infiltrating immune cells in
tumors,
chemokines are known to have antitumor effects.
Fractalkine, a unique CX3C
chemokine, is expressed in activated endothelial cells, while its receptor, CX3CR1, is expressed in cytolytic immune cells, such as natural killer cells, monocytes and some CD8+ T cells. The biological properties of
cancer cells are affected by the implantation organ and differences in immune systems, requiring
cancer implantation in orthotopic organs in an in vivo experiment. To develop new
therapy strategies for
lung cancer, an animal model reflecting the clinical features of
lung cancer was previously established. This study aimed to determine whether CX3CL1-induced biological functions should be used for immune cell-based gene therapy of
lung cancer in the orthotopic implantation model. An orthotopic intrapulmonary implantation of CX3CL1-stable expression in mouse
lung cancer (LLC-CX3CL1) was performed to analyze growth. Results showed a significant decrease in
tumor growth in the lung compared to the control cells (LLC-mock). Furthermore, the antitumor effects of CX3CL1 were derived from natural killer cell activities in the depletion experiment in vivo. Therefore, CX3CL1 has the potential of a useful therapeutic target in
lung cancer.