"Anti-cancer" effect of ketamine in comparison with MK801 on neuroglioma and lung cancer cells.

Ketamine, a N-methyl-D-aspartate (NMDA) receptor antagonist, is commonly used to induce anaesthesia during cancer surgery and relieve neuropathic and cancer pain. This study was conducted to assess whether ketamine has any inhibiting effects on neuroglioma (H4) and lung cancer cells (A549) in vitro. The cultured H4 and A549 cells were treated with ketamine and MK801 (0.1, 1, 10, 100, or 1000 μM) for 24 h. The expressions of glutamate receptors on both types of cancer cells were assessed with qRT-PCR. In addition, cell proliferation and migration were assessed with cell counting Kit-8 and wound healing assays. Cyclin D1, matrix metalloproteinase 9 (MMP9), phosphorylation of extracellular signal-regulated kinase (pERK), and cleaved-caspase-3 expression together with reactive oxygen species (ROS) were also assessed with Western blot, immunostaining, and/or flowcytometry. NMDA and α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors were expressed on both H4 and A549 cells. Ketamine inhibited cancer cell proliferation and migration in a dose-dependent manner by suppressing the cell cycle and inducing apoptosis. Ketamine decreased cyclin D1, pERK, and MMP9 expression. In addition, ketamine increased ROS and cleaved caspase-3 expression and induced apoptosis. The anti-cancer effect of ketamine was more pronounced in A549 cells when compared with H4 cells. MK801 showed similar effects to those of ketamine. Ketamine suppressed cell proliferation and migration in both neuroglioma and lung cancer cells, likely through the antagonization of NMDA receptors.