title: Upregulation of miR-501-5p activates the wnt/β-catenin signaling pathway and enhances stem cell-like phenotype in gastric cancer.
abstract: miRNAs are critical post-transcriptional regulators of gene expression and key mediators of tumourigenesis. miR-501-5p is newly identified to be involved in the tumor progression, but its biological role and mechanism remain largely unknown. This study is aimed to study the role of miR-501-5p in the progression of gastric cancer.
  
  
  
  Real-time PCR analysis was used to determine miR-501-5p expression in gastric cancer cell lines, clinical tissues and 112 clinicopathologically characterized gastric cancer specimens. The role of miR-501-5p in maintaining gastric cancer stem cell like phenotype was examined by tumor-sphere formation assay and expression of stem cell markers. Luciferase reporter assay, cellular fractionation and western blot analysis were used to determined that miR-501-5p activated the wnt/β-catenin signaling by directly targeting DKK1, NKD1 and GSK3β.
  
  
  
  Herein, our results revealed that miR-501-5p was markedly upregulated in gastric cancer cell lines and clinical tissues. High miR-501-5p levels predicted poor overall survival in gastric cancer patients. Gain-of-function and loss-of-function studies showed that ectopic expression of miR-501-5p enhanced the cancer stem cell-like phenotype in gastric cancer cells. Notably,wnt/β-catenin signaling was hyperactivated in gastric cancer cells that overexpress miR-501-5p, and mediated miR-501-5p-induced cancer stem cell-like phenotype. Furthermore, miR-501-5p directly targeted and suppressed multiple repressors of the wnt/β-catenin signaling cascade, including DKK1, NKD1 and GSK3β. These results demonstrate that miR-501-5p maintains constitutively activated wnt/β-catenin signaling by directly targeting DKK1, NKD1 and GSK3β, which promotes gastric cancer stem cell like phenotype.
  
  
  
  Taken together, our findings reveal a new regulatory mechanism of miR-501-5p and suggest that miR-501-5p might be a potential target in gastric cancer therapy.
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510405, China. dongmeifan9@sina.com.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Fan
authors.affiliation: Medical Department of Guangdong Hospital of Traditional Chinese Medicine, Guangzhou, 510405, China.
authors.forename: Baoqi
authors.initials: B
authors.lastname: Ren
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510405, China.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Yang
authors.affiliation: Third Affiliated Hospital of Guangzhou Medical College, Guangzhou, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510405, China.
authors.forename: Zhengzheng
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D002135:Calcium-Binding Proteins; D002352:Carrier Proteins / Q000235:genetics; D045744:Cell Line, Tumor; D015972:Gene Expression Regulation, Neoplastic; D000071679:Glycogen Synthase Kinase 3 beta / Q000235:genetics; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics; D035683:MicroRNAs / Q000235:genetics*; D014411:Neoplastic Stem Cells / Q000473:pathology*; D011379:Prognosis; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D016019:Survival Analysis; D015854:Up-Regulation; D060449:Wnt Signaling Pathway
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D002135:Calcium-Binding Proteins; D002352:Carrier Proteins; C501126:DKK1 protein, human; D036341:Intercellular Signaling Peptides and Proteins; C582676:MIRN501 microRNA, human; D035683:MicroRNAs; C449091:NKD1 protein, human; C000605506:GSK3B protein, human; D000071679:Glycogen Synthase Kinase 3 beta
keywords: Cancer stem cell; Gastric cancer; Wnt/β-catenin signaling; miR-501-5p