Molecular mechanisms of antitumor activity of niclosamide

The review summarizes literature data on the antitumor activity of niclosamide and its molecular mechanisms. Earlier niclosamide was used for treatment of intestinal parasitic infections. Recent screening of various drugs and chemical compounds, aimed at identifying putative agents with high antitumor activity, revealed that it possesses such activity. Niclosamide not only inhibits such signaling pathways as Wnt/β-cate-nin, mTORC1, Stat3, NF-κB and Notch, but also damages tumor cell mitochondria, inhibits proliferation and induces apoptosis. The effectiveness of niclosamide has been demonstrated in vitro experiments as well as in vivo models using xenotransplantation of human tumors to immunodeficient mice. Niclosamide was active not only against tumor cells but also cancer stem cells. Normal cells are resistant to niclosamide. The accumulated experimental data suggest that niclosamide is a promising pharmacological agent for the treatment of various types of cancer.