APR-246/PRIMA-1Met Inhibits and Reverses Squamous Metaplasia in Human Conjunctival Epithelium

Invest Ophthalmol Vis Sci. 2016 Feb;57(2):444-52. doi: 10.1167/iovs.15-17519.

Abstract

Purpose: Squamous metaplasia is a common pathologic condition in ocular surface diseases for which there is no therapeutic medication in clinic. In this study, we investigated the effect of a small molecule, APR-246/PRIMA-1(Met), on squamous metaplasia in human conjunctival epithelium.

Methods: Human conjunctival explants were cultured for up to 12 days under airlifting conditions. Epithelial cell differentiation and proliferation were assessed by Cytokeratin 10 (K10), K14, K19, Pax6, MUC5AC, and p63 immunostaining patterns. β-catenin and TCF-4 immunofluorescent staining and real-time PCR characterized Wnt signaling pathway involvement. Pterygium clinical samples were cultured under airlifting conditions with or without APR-246 for 4 days. p63, K10, β-catenin, and TCF-4 expression in pterygial epithelium was determined by immunofluorescent staining and real-time PCR.

Results: Airlift conjunctival explants resulted in increased stratification and intrastromal epithelial invagination. Such pathology was accompanied by increases in K10, K14, and p63 expression, whereas K19 and Pax6 levels declined when compared to those in freshly isolated tissue. On the other hand, APR-246 reversed all of these declines in K10, K14, and p63 expression. Furthermore, K19 and Pax6 increased along with rises in goblet cell density. These effects of APR-246 were accompanied by near restoration of normal conjunctival epithelial histology. APR-246 also reversed squamous metaplasia in pterygial epithelium that had developed after 4 days in ex vivo culture.

Conclusions: Reductions in squamous metaplasia induced by APR-246 suggest it may provide a novel therapeutic approach in different squamous metaplasia-associated ocular surface diseases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / metabolism
  • Biomarkers / metabolism
  • Cell Proliferation / drug effects*
  • Cell Transdifferentiation / drug effects*
  • Conjunctiva / metabolism
  • Conjunctiva / pathology*
  • Epithelium / metabolism
  • Epithelium / pathology*
  • Fluorescent Antibody Technique, Indirect
  • Humans
  • Keratin-10 / metabolism
  • Metaplasia
  • Organ Culture Techniques
  • Pterygium / metabolism
  • Pterygium / pathology
  • Pterygium / prevention & control*
  • Quinuclidines / pharmacology*
  • Real-Time Polymerase Chain Reaction
  • Transcription Factor 4
  • Transcription Factors / metabolism
  • Tumor Suppressor Proteins / metabolism
  • Wnt Signaling Pathway / drug effects
  • Wnt Signaling Pathway / genetics
  • beta Catenin / metabolism

Substances

  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors
  • Biomarkers
  • KRT10 protein, human
  • Quinuclidines
  • TCF4 protein, human
  • TP63 protein, human
  • Transcription Factor 4
  • Transcription Factors
  • Tumor Suppressor Proteins
  • beta Catenin
  • Keratin-10
  • eprenetapopt