MiR-93 functions as a tumor promoter in prostate cancer by targeting disabled homolog 2 (DAB2) and an antitumor polysaccharide from green tea (Camellia sinensis) on their expression

Int J Biol Macromol. 2019 Mar 15:125:557-565. doi: 10.1016/j.ijbiomac.2018.12.088. Epub 2018 Dec 10.

Abstract

Our previous work has demonstrated that the role of miR-93 in prostate cancer (PC) progression. The aim of this study was to determine the downstream gene regulated by miR-93 and the molecular mechanisms underlying its roles in PC. Bioinformatics analysis and luciferase reporter assays predicted disabled homolog 2 (DAB2) as a direct target gene of miR-93. Real time quantitative polymerase chain reaction (qRT-PCR) and Western blot analysis revealed that DAB2 was tumor repressor in PC cells, and its mRNA expression was negatively correlated with miR-93 in PC tissues. Gain and loss of function experiments also indicated DAB2 overexpression significantly suppressed PC cells proliferation, invasion and migration, while knockdown of its expression came to the opposite effect. Furthermore, a rescue experiment indicated miR-93 directly regulated PC cell growth and migration, as well as AKT and ERK activation by targeting DAB2. Additionally, antitumor effect of a Green tea polysaccharide (GTP) on PC-3 cells could be achieved by increasing DAB2 protein expression and inactivating AKT and ERK1/2 signaling. Our study suggests that miR-93 promoted PC progression and metastasis by repressing DAB2 to activate Akt/ERK1/2 pathway, and elevation of DAB2 and inactivation of Akt/ERK1/2 might be a potential therapeutic target for PC by GTP.

Keywords: Disabled homolog 2 (DAB2); Green tea polysaccharide; Prostate cancer.

MeSH terms

  • Adaptor Proteins, Signal Transducing / genetics*
  • Antineoplastic Agents / pharmacology*
  • Apoptosis Regulatory Proteins
  • Camellia sinensis / chemistry*
  • Cell Line, Tumor
  • Cell Movement / drug effects
  • Cell Movement / genetics
  • Cell Proliferation / drug effects
  • Cell Proliferation / genetics
  • Gene Expression Regulation, Neoplastic / drug effects
  • Gene Expression Regulation, Neoplastic / genetics
  • Humans
  • MAP Kinase Signaling System / drug effects
  • MAP Kinase Signaling System / genetics
  • Male
  • MicroRNAs / genetics*
  • PC-3 Cells
  • Polysaccharides / pharmacology*
  • Prostatic Neoplasms / genetics*
  • Signal Transduction / drug effects
  • Signal Transduction / genetics
  • Tea / chemistry*
  • Tumor Suppressor Proteins / genetics*

Substances

  • Adaptor Proteins, Signal Transducing
  • Antineoplastic Agents
  • Apoptosis Regulatory Proteins
  • DAB2 protein, human
  • MIRN93 microRNA, human
  • MicroRNAs
  • Polysaccharides
  • Tea
  • Tumor Suppressor Proteins