In:
Molecular Cancer Research, American Association for Cancer Research (AACR), Vol. 8, No. 5 ( 2010-05-01), p. 783-797
Abstract:
The atypical protein kinase Cζ (PKCζ) was recently shown to mediate epidermal growth factor (EGF)–induced activation of extracellular signal–regulated kinase (ERK) in head and neck squamous carcinoma (HNSCC) cells. Here, it is shown that EGF may induce tyrosine phosphorylation of PKCζ in several HNSCC cells, breast carcinoma cells, as well as mouse embryonic fibroblasts. In COS-7 cells overexpressing EGF receptor (EGFR) and PKCζ as a tumor cell model, we show that PKCζ tyrosine phosphorylation by EGF is induced by catalytic activation. Using a loss-of-function mutant of PKCζ, we can show that the tyrosine residue 417 in PKCζ plays an important role in both PKCζ activation and the ability of PKCζ to mediate activation of ERK. The importance of PKCζ in EGF-induced ERK activation can also be shown in several HNSCC and breast carcinoma cell lines as well as in PKCζ-deficient mouse embryonic fibroblasts. In addition, we present several lines of evidence suggesting the physical association of PKCζ with EGFR and the importance of the EGFR tyrosine kinase c-Src and the Src-specific phosphorylation site pY845-EGFR in the tyrosine phosphorylation as well as catalytic activation of PKCζ. This study characterizes PKCζ as a novel mitogenic downstream mediator of EGFR and indicates PKCζ as a therapeutic target in some carcinomas. Mol Cancer Res; 8(5); 783–97. ©2010 AACR.
Type of Medium:
Online Resource
ISSN:
1541-7786
,
1557-3125
DOI:
10.1158/1541-7786.MCR-09-0164
Language:
English
Publisher:
American Association for Cancer Research (AACR)
Publication Date:
2010
detail.hit.zdb_id:
2097884-4
SSG:
12
