Antihelminthic Niclosamide Induces Autophagy and Delayed Apoptosis in Human Non-small Lung Cancer Cells In Vitro and In Vivo.

Abstract

Niclosamide is an antihe-minthic drug that has shown cytotoxic effects on non-small cell lung carcinoma (NSCLC) cells. However, the exact mechanisms underlying the anti-tumour activity of niclosamide in NSCLC cancer cells remains to be defined. The aim of this study was to evaluate the antitumor activity of niclosamide in human A549 and CL1-5 non-small cell lung cancer cells using in vitro and in vivo. We investigated the effects of niclosamide on cell viability, apoptosis, the mitochondrial membrane potential (MMP; Δϕm), and autophagy and apoptosis-related protein expression in human A549 and CL1-5 non-small cell lung cancer cells. Niclosamide induced mainly caspase-independent apoptosis through apoptosis-inducible factor (AIF) translocation to the nucleus upon mitochondria damage. Moreover, niclosamide-induced autophagy may act as adaptive response against apoptosis. AMPK/AKT/mTOR pathway were involved in niclosamide-induced cell death and autophagy in response to ATP depletion. Furthermore, niclosamide efficiently suppressed tumor growth and induce autophagy in vivo. Niclosamide induced apoptosis by activating the intrinsic and caspase-independent pathway in human A549 and CL1-5 non-small cell lung cancer cells. Therefore, niclosamide is a potential candidate for anti-NSCLC therapy.