Niclosamide

Niclosamide (trade name Niclocide) is a teniacide in the anthelmintic family. Niclosamide inhibits the transcription of STAT3 target genes and induces cell growth inhibition, apoptosis and cell cycle arrest of cancer cells with constitutively active STAT3. It does not decrease the level or activity of the related STAT1, STAT5, JAK or Src kinases. Niclosamide also reversibly inhibits mTORC1 signaling and stimulates autophagy in vitro. Niclosamide inhibits the transcription and DNA binding of NF-κB. It blocks tumor necrosis factor-induced IκBα phosphorylation, translocation of p65, and expression of NF-κB– regulated genes in AML cells. Niclosamide inhibits the proliferation and colony formation of Du145 prostate cancer cells, which have constitutively active STAT3, with IC50 values of 0.7 and 0.1 μM, respectively.