Dual roles of the transcription factor grainyhead-like 2 (GRHL2) in breast cancer

TY - JOUR

T1 - Dual roles of the transcription factor grainyhead-like 2 (GRHL2) in breast cancer

AU - Werner, Stefan

AU - Frey, Sabrina

AU - Riethdorf, Sabine

AU - Schulze, Christian

AU - Alawi, Malik

AU - Kling, Lea

AU - Vafaizadeh, Vida

AU - Sauter, Guido

AU - Terracciano, Luigi

AU - Schumacher, Udo

AU - Pantel, Klaus

AU - Assmann, Volker

PY - 2013/8/9

Y1 - 2013/8/9

N2 - Using a retrovirus-mediated cDNA expression cloning approach, we identified the grainyhead-like 2 (GRHL2) transcription factor as novel protooncogene. Overexpression of GRHL2 in NIH3T3 cells induced striking morphological changes, an increase in cell proliferation, anchorage-independent growth, and tumor growth in vivo. By combining a microarray analysis and a phylogenetic footprinting analysis with various biochemical assays, we identified the epidermal growth factor receptor family member Erbb3 as a novel GRHL2 target gene. In breast cancer cell lines, shRNA-mediated knockdown of GRHL2 expression or functional inactivation of GRHL2 using dominant negative GRHL2 proteins induces down-regulation of ERBB3 gene expression, a striking reduction in cell proliferation, and morphological and phenotypical alterations characteristic of an epithelial-to-mesenchymal transition (EMT), thus implying contradictory roles of GRHL2 in breast carcinogenesis. Interestingly, we could further demonstrate that expression of GRHL2 is directly suppressed by the transcription factor zinc finger enhancer-binding protein 1 (ZEB1), which in turn is a direct target for repression by GRHL2, suggesting that the EMT transcription factors GRHL2 and ZEB1 form a double negative regulatory feedback loop in breast cancer cells. Finally, a comprehensive immunohistochemical analysis of GRHL2 expression in primary breast cancers showed loss of GRHL2 expression at the invasive front of primary tumors. A pathophysiological relevance of GRHL2 in breast cancer metastasis is further demonstrated by our finding of a statistically significant association between loss of GRHL2 expression in primary breast cancers and lymph node metastasis. We thus demonstrate a crucial role of GRHL2 in breast carcinogenesis.

AB - Using a retrovirus-mediated cDNA expression cloning approach, we identified the grainyhead-like 2 (GRHL2) transcription factor as novel protooncogene. Overexpression of GRHL2 in NIH3T3 cells induced striking morphological changes, an increase in cell proliferation, anchorage-independent growth, and tumor growth in vivo. By combining a microarray analysis and a phylogenetic footprinting analysis with various biochemical assays, we identified the epidermal growth factor receptor family member Erbb3 as a novel GRHL2 target gene. In breast cancer cell lines, shRNA-mediated knockdown of GRHL2 expression or functional inactivation of GRHL2 using dominant negative GRHL2 proteins induces down-regulation of ERBB3 gene expression, a striking reduction in cell proliferation, and morphological and phenotypical alterations characteristic of an epithelial-to-mesenchymal transition (EMT), thus implying contradictory roles of GRHL2 in breast carcinogenesis. Interestingly, we could further demonstrate that expression of GRHL2 is directly suppressed by the transcription factor zinc finger enhancer-binding protein 1 (ZEB1), which in turn is a direct target for repression by GRHL2, suggesting that the EMT transcription factors GRHL2 and ZEB1 form a double negative regulatory feedback loop in breast cancer cells. Finally, a comprehensive immunohistochemical analysis of GRHL2 expression in primary breast cancers showed loss of GRHL2 expression at the invasive front of primary tumors. A pathophysiological relevance of GRHL2 in breast cancer metastasis is further demonstrated by our finding of a statistically significant association between loss of GRHL2 expression in primary breast cancers and lymph node metastasis. We thus demonstrate a crucial role of GRHL2 in breast carcinogenesis.

KW - Animals

KW - Breast Neoplasms

KW - Cell Line, Tumor

KW - DNA-Binding Proteins

KW - Female

KW - Gene Expression Regulation, Neoplastic

KW - Homeodomain Proteins

KW - Humans

KW - Kruppel-Like Transcription Factors

KW - Lymphatic Metastasis

KW - Mammary Neoplasms, Animal

KW - Mice

KW - NIH 3T3 Cells

KW - Receptor, erbB-2

KW - Transcription Factors

U2 - 10.1074/jbc.M113.456293

DO - 10.1074/jbc.M113.456293

M3 - SCORING: Journal article

C2 - 23814079

VL - 288

SP - 22993

EP - 23008

JO - J BIOL CHEM

JF - J BIOL CHEM

SN - 0021-9258

IS - 32

ER -