Three-Dimensional Cell Culture-Based Screening Identifies the Anthelmintic Drug Nitazoxanide as a Candidate for Treatment of Colorectal Cancer.
Because dormant cancer cells in hypoxic and nutrient-deprived regions of solid tumors provide a major obstacle to treatment, compounds targeting those cells might have clinical benefits. Here, we describe a high-throughput drug screening approach, using glucose-deprived multicellular tumor spheroids (MCTS) with inner hypoxia, to identify compounds that specifically target this cell population. We used a concept of drug repositioning-using known molecules for new indications. This is a promising strategy to identify molecules for rapid clinical advancement. By screening 1,600 compounds with documented clinical history, we aimed to identify candidates with unforeseen potential for repositioning as anticancer drugs. Our screen identified five molecules with pronounced MCTS-selective activity: nitazoxanide, niclosamide, closantel, pyrvinium pamoate, and salinomycin. Herein, we show that all five compounds inhibit mitochondrial respiration. This suggests that cancer cells in low glucose concentrations depend on oxidative phosphorylation rather than solely glycolysis. Importantly, continuous exposure to the compounds was required to achieve effective treatment. Nitazoxanide, an FDA-approved antiprotozoal drug with excellent pharmacokinetic and safety profile, is the only molecule among the screening hits that reaches high plasma concentrations persisting for up to a few hours after single oral dose. Nitazoxanide activated the AMPK pathway and downregulated c-Myc, mTOR, and Wnt signaling at clinically achievable concentrations. Nitazoxanide combined with the cytotoxic drug irinotecan showed anticancer activity in vivo. We here report that the FDA-approved anthelmintic drug nitazoxanide could be a potential candidate for advancement into cancer clinical trials.
Department of Medical Sciences, Division of Cancer Pharmacology and Computational Medicine, Uppsala University, Uppsala, Sweden.
Wojciech
W
Senkowski
Department of Oncology-Pathology, Karolinska Institute, Stockholm, Sweden.
Xiaonan
X
Zhang
Department of Oncology-Pathology, Karolinska Institute, Stockholm, Sweden.
Maria Hägg
MH
Olofsson
Adlego Biomedical AB, Stockholm, Sweden.
Ruben
R
Isacson
Adlego Biomedical AB, Stockholm, Sweden.
Urban
U
Höglund
Department of Medical Sciences, Division of Cancer Pharmacology and Computational Medicine, Uppsala University, Uppsala, Sweden.
Mats
M
Gustafsson
Department of Radiology, Oncology and Radiation Sciences, Division of Oncology Uppsala University, Uppsala, Sweden.
Peter
P
Nygren
Department of Oncology-Pathology, Karolinska Institute, Stockholm, Sweden. Department of Medical and Health Sciences, Linköping University, Linköping, Sweden.
Stig
S
Linder
Department of Medical Sciences, Division of Cancer Pharmacology and Computational Medicine, Uppsala University, Uppsala, Sweden.
Rolf
R
Larsson
Department of Medical Sciences, Division of Cancer Pharmacology and Computational Medicine, Uppsala University, Uppsala, Sweden. marten.fryknas@medsci.uu.se.
Mårten
M
Fryknäs
D000284:Administration, Oral; D000818:Animals; D000871:Anthelmintics / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology; D018929:Cell Culture Techniques / Q000379:methods*; D015687:Cell Hypoxia; D002470:Cell Survival / Q000187:drug effects; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D058492:Drug Repositioning / Q000379:methods; D004354:Drug Screening Assays, Antitumor / Q000379:methods; D005260:Female; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D045325:HCT116 Cells; D019073:HT29 Cells; D006801:Humans; D008815:Mice, Inbred Strains; D008819:Mice, Nude; D008856:Microscopy, Fluorescence; D009574:Nitro Compounds; D010085:Oxidative Phosphorylation / Q000187:drug effects; D015398:Signal Transduction / Q000187:drug effects; D018874:Spheroids, Cellular / Q000187:drug effects / Q000378:metabolism; D013844:Thiazoles / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology*; D023041:Xenograft Model Antitumor Assays
D000871:Anthelmintics; D000970:Antineoplastic Agents; D009574:Nitro Compounds; D013844:Thiazoles; D049452:Green Fluorescent Proteins; C041747:nitazoxanide