Imipramine (IMI) is a tricyclic synthetic antidepressant that is used to treat chronic psychiatric disorders, including depression and neuropathic pain. IMI also has inhibitory effects against various cancer types, including prostate cancer; however, the mechanism of its anticancer activity is not well understood. In the present study, we investigated the antimetastatic and anti-invasive effects of IMI in metastatic castration-resistant prostate cancer PC-3 cells, with an emphasis on the serine/threonine protein kinase AKT-mediated nuclear factor kappa B (NF-κB) signaling pathway. While IMI did not induce cell death, it attenuated PC-3 cell proliferation. According to the wound healing assay and invasion assay, migration and invasion in PC-3 cells were significantly inhibited by IMI in a dose-dependent manner. IMI significantly downregulated p-AKT protein expression but upregulated phospho-extracellular signal-regulated kinase (ERK1)/2 protein expression levels. Furthermore, IMI treatment resulted in decreased AKT-mediated downstream signaling, including p-inhibitor of κB kinase (IKK)α/β, p-inhibitor of κB (IκBα), and p-p65. Inhibited NF-κB signaling reduced the secretion of several proinflammatory cytokines and chemokine by PC-3 cells. Overall, our study explored the negative correlation between the use of antidepressants and prostate cancer progression, showing that IMI attenuated cell viability, migration, and invasion of PC-3 cells by suppressing the expression of AKT and NF-κB-related signaling proteins and secretion of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and monocyte chemoattractant protein-1 (MCP-1).
Keywords: antidepressants; imipramine; invasion; migration; prostate cancer.