A positive feedback loop of p53/miR-19/TP53INP1 modulates pancreatic cancer cell proliferation and apoptosis

Oncol Rep. 2016 Jan;35(1):518-23. doi: 10.3892/or.2015.4361. Epub 2015 Oct 30.

Abstract

Pancreatic cancer is a common malignancy whose prognosis and treatment of pancreatic cancer is extremely poor, with only 20% of patients reaching two years of survival. Previous findings have shown that the tumor suppressor p53 is involved in the development of various types of cancer, including pancreatic cancer. Additionally, p53 is able to activate TP53INP1 transcription by regulating several phenotypes of cancer cells. Using gain and loss-of-function assays, the aim of the present study was to examine the relationships between miR-19a/b and cancer development as well as potential underlying mechanisms. The results showed that miR-19a/b identified a positive feedback regulation of p53/TP53INP1 axis. Additionally, p53 upregulated the TP53INP1 level in pancreatic cancer cells. However, overexpressed miR-19a/b partially restored the TP53 function in the pancreatic cancer cells while miR-19a/b downregulated TP53INP1 protein by directly targeting 3'UTR of its mRNA at the post-transcriptional level. In addition, the patient tissues identified that the miR-19a/b level in pancreatic cancer tissues was conversely correlated with TP53 and TP53INP1 expression. The results provide evidence for revealing the molecular mechanism involved in the development of pancreatic cancer and may be useful in the identification of new therapeutic targets for pancreatic cancer.

MeSH terms

  • 3' Untranslated Regions
  • Apoptosis
  • Carrier Proteins / genetics*
  • Carrier Proteins / metabolism
  • Cell Line, Tumor
  • Cell Proliferation
  • Cell Survival
  • Gene Expression Regulation, Neoplastic
  • Heat-Shock Proteins / genetics*
  • Heat-Shock Proteins / metabolism
  • Humans
  • MicroRNAs / genetics*
  • MicroRNAs / metabolism
  • Pancreatic Neoplasms / genetics
  • Pancreatic Neoplasms / metabolism*
  • Pancreatic Neoplasms / pathology
  • Tumor Suppressor Protein p53 / genetics*
  • Tumor Suppressor Protein p53 / metabolism

Substances

  • 3' Untranslated Regions
  • Carrier Proteins
  • Heat-Shock Proteins
  • MIRN19 microRNA, human
  • MicroRNAs
  • TP53 protein, human
  • TP53INP1 protein, human
  • Tumor Suppressor Protein p53