The tea polyphenols EGCG and EGC repress mRNA expression of human telomerase reverse transcriptase (hTERT) in carcinoma cells

Cancer Lett. 2006 May 8;236(1):80-8. doi: 10.1016/j.canlet.2005.05.003. Epub 2005 Jun 21.

Abstract

Tea polyphenols have inhibitive effects for carcinogenesis. A reporter system controlled by hTERT promoter was constructed to evaluate the effects of tea polyphenols, (-)-epigallocatechin-3-gallate (EGCG) and (-)-epigallocatechin (EGC) on the repression of hTERT transcription. The hTERT promoter activity was selectively repressed by 20-40 microM EGCG and EGC in a dose- and time-dependent manner. Real-time RT-PCR confirmed that the endogenous hTERT mRNA level was decreased in H1299, OECM-1 and SAS cells treated with EGCG or EGC. Our results identified the repression activities of EGCG and EGC toward telomerase expression that might be linked to inhibition of carcinoma cell growth. This cell-based reporter system is useful for screening drugs targeting hTERT repression.

Publication types

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

MeSH terms

  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Apoptosis
  • Camellia sinensis
  • Catechin / administration & dosage
  • Catechin / analogs & derivatives*
  • Catechin / pharmacology
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • DNA-Binding Proteins / biosynthesis
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • Dose-Response Relationship, Drug
  • Down-Regulation
  • Drug Delivery Systems / methods
  • Gene Expression Regulation, Neoplastic / drug effects*
  • Humans
  • Promoter Regions, Genetic / drug effects
  • RNA, Messenger / metabolism
  • Telomerase / biosynthesis
  • Telomerase / genetics*
  • Telomerase / metabolism
  • Time Factors

Substances

  • Antineoplastic Agents, Phytogenic
  • DNA-Binding Proteins
  • RNA, Messenger
  • Catechin
  • epigallocatechin gallate
  • Telomerase
  • gallocatechol