Cholesteatoma growth and proliferation: posttranscriptional regulation by microRNA-21. Otol Neurotol 2009 Oct;30(7):998-1005
Date
08/13/2009Pubmed ID
19672202Pubmed Central ID
PMC2828528DOI
10.1097/MAO.0b013e3181b4e91fScopus ID
2-s2.0-70349755838 (requires institutional sign-in at Scopus site) 58 CitationsAbstract
OBJECTIVES: The goal of this study was to identify novel regulatory mechanisms controlling the growth and proliferation of cholesteatoma. Specifically, the potential role of microRNAs, regulators of protein translation, was studied in cholesteatoma.
STUDY DESIGN: This study represents a molecular biologic investigation characterizing and comparing microRNA and protein expression in cholesteatoma and normal postauricular skin.
METHODS: Cholesteatoma and normal skin were taken from patients at the time of surgery. Tissue was processed for RNA and protein extraction. Real-time reverse-transcriptase-polymerase chain reaction was used to assess levels of human microRNAs, reverse-transcriptase-polymerase chain reaction was used to confirm the presence of upstream regulators, and Western blot analyses were used to assess levels of downstream target proteins.
RESULTS: Among the microRNAs investigated, human microRNA-21 (hsa-miR-21) showed a 4.4-fold higher expression in cholesteatoma as compared with normal skin (p = 0.0011). The downstream targets of hsa-miR-21, PTEN and programmed cell death 4, were found to be greatly reduced in 3 of 4 cholesteatoma samples. Proposed upstream regulators of hsa-miR-21 expression (CD14, interleukin 6R, gp130, and signal transducer and activator of transcription 3) were present in all cholesteatoma tissues.
CONCLUSION: MicroRNAs represent powerful regulators of protein translation, and their dysregulation has been implicated in many neoplastic diseases. This study specifically identified up-regulation of hsa-miR-21 concurrent with down-regulation of potent tumor suppressor proteins PTEN and programmed cell death 4. These proteins control aspects of apoptosis, proliferation, invasion, and migration. The results of this study were used to develop a model for cholesteatoma proliferation through microRNA dysregulation. This model can serve as a template for further study into potential RNA-based therapies for the treatment of cholesteatoma.
Author List
Friedland DR, Eernisse R, Erbe C, Gupta N, Cioffi JAMESH terms used to index this publication - Major topics in bold
AdultApoptosis Regulatory Proteins
Cell Proliferation
Cholesteatoma
Ear
Humans
Lipopolysaccharide Receptors
MicroRNAs
PTEN Phosphohydrolase
RNA Processing, Post-Transcriptional
RNA-Binding Proteins
Receptors, Interleukin-6
Reverse Transcriptase Polymerase Chain Reaction
STAT3 Transcription Factor
Skin
Up-Regulation
