Renal cell carcinoma (RCC) is likely to metastasize to other organs, and is often resistant to conventional chemotherapies. Thymoquinone (TQ), a phytochemical derived from the seeds of Nigella sativa, has been shown to inhibit migration and metastasis in various cancers. In this study, we assessed the effect of TQ on the migratory activity of human RCC Caki-1 cells. We found that treatment with TQ reduced the proteolytic activity of matrix metalloproteinase-9 (MMP-9) in Caki-1 cells. TQ significantly repressed prostaglandin E2(PGE2) production, its EP2 receptor expression as well as the activation of Akt and p38, the wellknown upstream signal proteins of MMP-9. In addition, treatment with butaprost, a PGE2 agonist, also induced MMP-9 activity and migration/invasion in Caki-1 cells. Moreover, pharmacological inhibitors of PI3K/Akt and p38 remarkably attenuated butaprostinduced Caki-1 cell migration and invasion, implying that activation of PI3K/Akt and p38 is a bridge between the PGE2-EP2 axis and MMP-9-dependent migration and invasion. Taken together, these data suggest that TQ is a promising anti-metastatic drug to treat advanced and metastatic RCC.

Renal cancer continues to offer a great challenge for its successful therapy today, thus underscoring the need for effective chemotherapeutic agents. In the current study, we explored the anticancer effects of domperidone, a dopamine D2 receptor (DRD2) antagonist, in renal cancer Caki-2 cells. Domperidone induced dose and time-dependent cytotoxic effects in Caki-2 cells, triggering intrinsic apoptosis via the stimulation of the caspase cascade and PARP cleavage. The cytotoxic effect of domperidone was found to be partially DRD2-dependent. Domperidone treatment markedly augmented the production of intracellular reactive oxygen species which induced the cell death of Caki-2 cells. In addition, domperidone suppressed Janus kinase 2 and STAT3 phosphorylation, leading to inhibition of survival and proliferation of these cells. Hence, domperidone can be considered a promising candidate for renal cancer treatment.

Renal cancer continues to offer a great challenge for its successful therapy today, thus underscoring the need for effective chemotherapeutic agents. In the current study, we explored the anticancer effects of domperidone, a dopamine D2 receptor (DRD2) antagonist, in renal cancer Caki-2 cells. Domperidone induced dose and time-dependent cytotoxic effects in Caki-2 cells, triggering intrinsic apoptosis via the stimulation of the caspase cascade and PARP cleavage. The cytotoxic effect of domperidone was found to be partially DRD2-dependent. Domperidone treatment markedly augmented the production of intracellular reactive oxygen species which induced the cell death of Caki-2 cells. In addition, domperidone suppressed Janus kinase 2 and STAT3 phosphorylation, leading to inhibition of survival and proliferation of these cells. Hence, domperidone can be considered a promising candidate for renal cancer treatment.

Renal cancer continues to offer a great challenge for its successful therapy today, thus underscoring the need for effective chemotherapeutic agents. In the current study, we explored the anticancer effects of domperidone, a dopamine D2 receptor (DRD2) antagonist, in renal cancer Caki-2 cells. Domperidone induced dose and time-dependent cytotoxic effects in Caki-2 cells, triggering intrinsic apoptosis via the stimulation of the caspase cascade and PARP cleavage. The cytotoxic effect of domperidone was found to be partially DRD2-dependent. Domperidone treatment markedly augmented the production of intracellular reactive oxygen species which induced the cell death of Caki-2 cells. In addition, domperidone suppressed Janus kinase 2 and STAT3 phosphorylation, leading to inhibition of survival and proliferation of these cells. Hence, domperidone can be considered a promising candidate for renal cancer treatment.