Format

Send to

Choose Destination

RETRACTED ARTICLE

See: Retraction Notice

Am J Pathol. 2009 Aug;175(2):557-70. doi: 10.2353/ajpath.2009.080853. Epub 2009 Jul 23.

RETRACTED: Identification of phosphorylated p38 as a novel DAPK-interacting partner during TNFalpha-induced apoptosis in colorectal tumor cells.

Author information

1
Experimental Tumor Pathology, Institute of Pathology, University of Erlangen-Nuremberg, Universitätsstr. 22, 91054 Erlangen, Germany.

Retraction in

Abstract

Death-associated protein kinase (DAPK) is a serine/threonine kinase that contributes to pro-apoptotic signaling on cytokine exposure. The role of DAPK in macrophage-associated tumor cell death is currently unknown. Recently, we suggested a new function for DAPK in the induction of apoptosis during the interaction between colorectal tumor cells and tumor-associated macrophages. Using a cell-culture model with conditioned supernatants of differentiated/activated macrophages (U937) and human HCT116 colorectal tumor cells, we replicated DAPK-associated tumor cell death; this model likely reflects the in vivo tumor setting. In this study, we show that tumor necrosis factor-alpha exposure under conditions of macrophage activation induced DAPK-dependent apoptosis in the colorectal tumor cell line HCT116. Simultaneously, early phosphorylation of p38 mitogen-activated protein kinase (phospho-p38) was observed. We identified the phospho-p38 mitogen-activated protein kinase as a novel interacting protein of DAPK in tumor necrosis factor-alpha-induced apoptosis. The general relevance of this interaction was verified in two colorectal cell lines without functional p53 (ie, HCT116 p53(-/-) and HT29 mutant) and in human colon cancer and ulcerative colitis tissues. Supernatants of freshly isolated human macrophages were also able to induce DAPK and phospho-p38. Our findings highlight the mechanisms that underlie DAPK regulation in tumor cell death evoked by immune cells.

PMID:
19628771
PMCID:
PMC2716956
DOI:
10.2353/ajpath.2009.080853
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center