Green tea polyphenol epigallocatechin-3 gallate inhibits Her-2/neu signaling, proliferation, and transformed phenotype of breast cancer cells.
Overexpression of the epidermal growth factor receptor family member Her-2/neu in breast cancer is associated with poor prognosis. With evidence accumulating for a chemopreventive role of green tea polyphenols, the effects of epigallocatechin-3 gallate (EGCG) on Her-2/neu-overexpressing breast cancer cells were examined. EGCG inhibited mouse mammary tumor virus (MMTV)-Her-2/neu NF639 cell growth in culture and soft agar. EGCG reduced signaling via the phosphatidylinositol 3- kinase, Akt kinase to NF-kappaB pathway because of inhibition of basal Her-2/neu receptor tyrosine phosphorylation. EGCG similarly inhibited basal receptor phosphorylation in SMF and Ba/F3 2 + 4 cells, which suggests the potential beneficial use of EGCG in adjuvant therapy of tumors with Her-2/neu overexpression.
Pianetti
Stefania
S
Department of Biochemistry, Boston University School of Medicine, 715 Albany Street, Boston, MA 02118-2394, USA.
Guo
Shangqin
S
Kavanagh
Kathryn T
KT
Sonenshein
Gail E
GE
D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D001628:Beverages; D002392:Catechin / Q000031:analogs & derivatives / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D002471:Cell Transformation, Neoplastic / Q000187:drug effects*; D005260:Female; D006131:Growth Inhibitors / Q000494:pharmacology; D008325:Mammary Neoplasms, Experimental / Q000473:pathology* / Q000517:prevention & control; D051379:Mice; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000502:physiology; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010766:Phosphorylation / Q000187:drug effects; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins / Q000037:antagonists & inhibitors / Q000502:physiology; D051057:Proto-Oncogene Proteins c-akt; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000037:antagonists & inhibitors* / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects
D016588:Anticarcinogenic Agents; D002392:Catechin; D006131:Growth Inhibitors; D016328:NF-kappa B; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D051057:Proto-Oncogene Proteins c-akt; D018719:Erb-b2 Receptor Tyrosine Kinases; C045651:epigallocatechin gallate