title: Wnt blockers inhibit the proliferation of lung cancer stem cells.
abstract: BACKGROUND
  Previous study has confirmed that the occurrence of Wnt pathway activation is associated with risk of non-small-cell lung cancer recurrence. However, whether the pharmacologic blocking of the Wnt signaling pathway could provide therapeutic possibility remains unknown. The aim of the present study was to evaluate the therapeutic functions of the Wnt signaling pathway inhibitor pyrvinium pamoate (PP) on lung cancer stem cells (LCSCs) in vitro.
  
  
  METHODS
  Colony formation and sphere culture were performed to enrich LCSCs from three lung cancer cell lines: PC9, SPC-A1, and A549. After confirming stemness by immunofluorescence, PP was employed for cell viability assay by comparison with three other kinds of Wnt signaling inhibitor: salinomycin, ICG-001, and silibinin. The effect of PP on LCSCs was further verified by colony formation assay and gene expression analysis.
  
  
  RESULTS
  LCSCs were successfully generated by sphere culture from SPC-A1 and PC9 cells, but not A549 cells. Immunofluorescence assay showed that LCSCs could express pluripotent stem cell markers, including NANOG, Oct4, KLF5, and SOX2, and Wnt signaling pathway molecules β-catenin and MYC. Half-maximal inhibitory concentrations of PP on SPC-A1, PC9, and A549 were 10 nM, 0.44 nM, and 0.21 nM, respectively, which are much lower than those of salinomycin, ICG-001, and silibinin. Moreover, significantly decreased colony formation and downregulation of pluripotent stem cell signaling pathway were observed in lung cancer cells after treatment with PP.
  
  
  CONCLUSIONS
  Wnt signaling inhibitor PP can inhibit proliferation of LCSCs, and the Wnt signaling pathway could be considered a promising therapeutic or interventional target in lung adenocarcinoma.
authors.affiliation: Department of Pulmonary Medicine, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China.
authors.forename: Xueyan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Pulmonary Medicine, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China.
authors.forename: Yuqing
authors.initials: Y
authors.lastname: Lou
authors.affiliation: Department of Pulmonary Medicine, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China.
authors.forename: Xiaoxuan
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Department of Pulmonary Medicine, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China.
authors.forename: Huimin
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Pulmonary Medicine, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China.
authors.forename: Jiayuan
authors.initials: J
authors.lastname: Sun
authors.affiliation: Section of Cancer Stem Cells, Shanghai Cancer Institute, Shanghai Jiaotong University, Shanghai, People's Republic of China.
authors.forename: Qianggang
authors.initials: Q
authors.lastname: Dong
authors.affiliation: Department of Pulmonary Medicine, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China.
authors.forename: Baohui
authors.initials: B
authors.lastname: Han
mesh_terms: D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D008175:Lung Neoplasms / Q000473:pathology*; D014411:Neoplastic Stem Cells / Q000187:drug effects*; D011774:Pyrvinium Compounds / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects; D014410:Tumor Stem Cell Assay; D051153:Wnt Proteins / Q000037:antagonists & inhibitors*; D060449:Wnt Signaling Pathway / Q000187:drug effects
chemical_list: D011774:Pyrvinium Compounds; D051153:Wnt Proteins; C024631:pyrvinium
keywords: Wnt signaling pathway; colony formation; pyrvinium pamoate; sphere culture