Abstract
Objective:
To elucidate the interference effect of Epigallocatechin-3-Gallate (EGCG) on targets of Activator Protein-1 (AP-1) signal transduction pathway activated by EB virus encoded latent membrane protein 1 in nasopharyngeal carcinoma (NPC) cell lines.
Methods:
Survival rate of cells was determined by MTT assay. AP-1 and CyclinD1 activation were analyzed by promoter luciferase reporter system. Nuclear translocation of JNK was analyzed by indirect immunofluorescence. Protein expression and phosphorylation were observed by Western blot.
Results:
EGCG inhibited the survival of CNE1 and CNE-LMP1 cells and the activity of AP-1 caused by LMP1 in CNE-LMP1 cells. EGCG also inhibited the nuclear translocation of JNK and the phosphorylation of c-Jun. It also inhibited cyclinD1 promoter activity and cyclinD1 expression.
Conclusion:
EGCG inhibits AP-1, JNK, c-Jun and cyclinD1 which are key targets on AP-1 signal transduction pathway. The results may explain the molecular mechanism of action of EGCG against nasopharyngeal carcinoma.
Publication types
-
English Abstract
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Carcinoma, Squamous Cell / metabolism
-
Carcinoma, Squamous Cell / pathology
-
Carcinoma, Squamous Cell / virology
-
Catechin / analogs & derivatives*
-
Catechin / pharmacology*
-
Cell Line, Tumor
-
Cell Survival / drug effects
-
Herpesvirus 4, Human
-
Humans
-
JNK Mitogen-Activated Protein Kinases / metabolism
-
MAP Kinase Kinase 4
-
Mitogen-Activated Protein Kinase Kinases / metabolism
-
Nasopharyngeal Neoplasms / metabolism*
-
Nasopharyngeal Neoplasms / pathology
-
Nasopharyngeal Neoplasms / virology
-
Phosphorylation / drug effects
-
Protein Transport / drug effects
-
Proto-Oncogene Proteins c-jun / metabolism
-
Signal Transduction / drug effects*
-
Transcription Factor AP-1 / metabolism*
-
Viral Matrix Proteins / genetics
-
Viral Matrix Proteins / metabolism
-
Viral Matrix Proteins / physiology*
Substances
-
EBV-associated membrane antigen, Epstein-Barr virus
-
Proto-Oncogene Proteins c-jun
-
Transcription Factor AP-1
-
Viral Matrix Proteins
-
Catechin
-
epigallocatechin gallate
-
JNK Mitogen-Activated Protein Kinases
-
MAP Kinase Kinase 4
-
Mitogen-Activated Protein Kinase Kinases