Targeting of alpha-v integrins reduces malignancy of bladder carcinoma

PLoS One. 2014 Sep 23;9(9):e108464. doi: 10.1371/journal.pone.0108464. eCollection 2014.

Abstract

Low survival rates of metastatic cancers emphasize the need for a drug that can prevent and/or treat metastatic cancer. αv integrins are involved in essential processes for tumor growth and metastasis and targeting of αv integrins has been shown to decrease angiogenesis, tumor growth and metastasis. In this study, the role of αv integrin and its potential as a drug target in bladder cancer was investigated. Treatment with an αv integrin antagonist as well as knockdown of αv integrin in the bladder carcinoma cell lines, resulted in reduced malignancy in vitro, as illustrated by decreased proliferative, migratory and clonogenic capacity. The CDH1/CDH2 ratio increased, indicating a shift towards a more epithelial phenotype. This shift appeared to be associated with downregulation of EMT-inducing transcription factors including SNAI2. The expression levels of the self-renewal genes NANOG and BMI1 decreased as well as the number of cells with high Aldehyde Dehydrogenase activity. In addition, self-renewal ability decreased as measured with the urosphere assay. In line with these observations, knockdown or treatment of αv integrins resulted in decreased metastatic growth in preclinical in vivo models as assessed by bioluminescence imaging. In conclusion, we show that αv integrins are involved in migration, EMT and maintenance of Aldehyde Dehydrogenase activity in bladder cancer cells. Targeting of αv integrins might be a promising approach for treatment and/or prevention of metastatic bladder cancer.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aldehyde Dehydrogenase / biosynthesis
  • Aldehyde Dehydrogenase / genetics
  • Animals
  • Carcinoma, Transitional Cell / pathology*
  • Cell Adhesion / drug effects
  • Cell Line, Tumor
  • Cell Movement / drug effects
  • Cell Self Renewal / drug effects
  • Epithelial-Mesenchymal Transition / drug effects
  • Female
  • Gene Expression Regulation, Neoplastic / drug effects
  • Genetic Vectors / pharmacology*
  • Heart
  • Humans
  • Integrin alphaV / drug effects*
  • Integrin alphaV / physiology
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • Molecular Targeted Therapy*
  • Neoplasm Invasiveness
  • Neoplasm Proteins / antagonists & inhibitors*
  • Neoplasm Proteins / biosynthesis
  • Neoplasm Proteins / genetics
  • Neoplasm Transplantation / methods
  • Papilloma / pathology
  • RNA Interference*
  • RNA, Small Interfering / pharmacology*
  • Receptors, Vitronectin / antagonists & inhibitors*
  • Receptors, Vitronectin / physiology
  • Tibia
  • Transcription Factors / biosynthesis
  • Transcription Factors / genetics
  • Transduction, Genetic
  • Tumor Stem Cell Assay
  • Urinary Bladder Neoplasms / pathology*
  • Xenograft Model Antitumor Assays

Substances

  • Integrin alphaV
  • Neoplasm Proteins
  • RNA, Small Interfering
  • Receptors, Vitronectin
  • Transcription Factors
  • integrin alphaVbeta5
  • Aldehyde Dehydrogenase

Grants and funding

This work is supported by a grant from the Dutch Cancer Society UL 2011-4930. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.