Preclinical validation of talaporfin sodium-mediated photodynamic therapy for esophageal squamous cell carcinoma

PLoS One. 2014 Aug 4;9(8):e103126. doi: 10.1371/journal.pone.0103126. eCollection 2014.

Abstract

Photodynamic therapy (PDT) kills cancer cells via a photochemical reaction mediated by an oncotropic photosensitizer. Herein, we performed an experimental preclinical study to validate the anti-tumour effect of talaporfin sodium-mediated PDT (t-PDT) for esophageal squamous cell carcinoma (ESCC) cells. We used human ESCC cells derived from various differentiation grades or resistant to 5-fluorouracil (5-FU). The cytotoxic effect of t-PDT was determined by evaluating cell viability, apoptosis and generation of reactive oxygen species (ROS) and DNA double-strand breaks. Furthermore, the anti-tumour effect of t-PDT was assessed using an anchorage-independent cell-growth assay and xenograft transplantation models. t-PDT induced potent cytotoxicity in ESCC cells independent of their differentiation grade or 5-FU resistance. Moreover, t-PDT induced robust apoptosis, as indicated by cell shrinkage, perinuclear vacuolization, nuclear fragmentation and induction of annexin V-positive cells. This apoptotic response was accompanied by concurrent activation of ROS, and induction of DNA double-strand breakage. Importantly, t-PDT suppressed efficiently anchorage-independent cell growth as well as ESCC-xenografted tumor formation. In aggregate, t-PDT showed anti-tumor potential for ESCC cells with various histological grades or chemoresistance, providing a novel translational rationale of t-PDT for the treatment of ESCC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Carcinoma, Squamous Cell / drug therapy*
  • Carcinoma, Squamous Cell / pathology
  • Cell Adhesion / drug effects
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • DNA Breaks, Double-Stranded / drug effects
  • Esophageal Neoplasms / drug therapy*
  • Esophageal Neoplasms / pathology
  • Esophageal Squamous Cell Carcinoma
  • Fluorescence
  • Humans
  • Intracellular Space / drug effects
  • Intracellular Space / metabolism
  • Mice
  • Photochemotherapy*
  • Porphyrins / pharmacology
  • Porphyrins / therapeutic use*
  • Reactive Oxygen Species / metabolism
  • Reproducibility of Results

Substances

  • Porphyrins
  • Reactive Oxygen Species
  • Talaporfin

Grants and funding

This study was supported by a Health and Labor Sciences Research Grant, Research on Clinical Trial on Development of New Drugs and Medical Devices (H24-012). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.