Roland Schüle | Albert-Ludwigs-Universität Freiburg (original) (raw)

Papers by Roland Schüle

Oncotarget, Jan 20, 2015

A lack of cell surface markers for the specific identification, isolation and subsequent analysis... more A lack of cell surface markers for the specific identification, isolation and subsequent analysis of living prostate tumor cells hampers progress in the field. Specific characterization of tumor cells and their microenvironment in a multi-parameter molecular assay could significantly improve prognostic accuracy for the heterogeneous prostate tumor tissue. Novel functionalized gold-nano particles allow fluorescence-based detection of absolute mRNA expression levels in living cells by fluorescent activated flow cytometry (FACS). We use of this technique to separate prostate tumor and benign cells in human prostate needle biopsies based on the expression levels of the tumor marker alpha-methylacyl-CoA racemase (AMACR). We combined RNA and protein detection of living cells by FACS to gate for epithelial cell adhesion molecule (EPCAM) positive tumor and benign cells, EPCAM/CD45 double negative mesenchymal cells and CD45 positive infiltrating lymphocytes. EPCAM positive epithelial cells w...

Molecular and cellular biology, 1999

The orphan receptor germ cell nuclear factor (GCNF) is a member of the superfamily of nuclear rec... more The orphan receptor germ cell nuclear factor (GCNF) is a member of the superfamily of nuclear receptors. During development, GCNF exhibits a restricted brain-specific expression pattern, whereas GCNF expression in the adult is germ cell specific. Therefore, the receptor may participate in the regulation of neurogenesis and reproductive functions. No natural GCNF target gene has yet been identified, but recent data demonstrate specific and high-affinity binding of GCNF either to the direct repeat DNA element AGGTCAAGGTCA (DR0) or to extended half-sites, such as TCAAGGTCA. In this study, we show that murine GCNF (mGCNF) can bind as a homodimer to extended half-sites, thus describing a novel property within the nuclear receptor superfamily. Homodimeric binding to extended half-sites requires the presence of a dimerization function within the mGCNF DNA-binding domain (DBD) and a novel dimerization surface encompassing the putative helix 3 and the helix 12 region of the mGCNF ligand-bind...

Oncotarget, Jan 10, 2015

The histone code reader Spindlin1 (SPIN1) has been implicated in tumorigenesis and tumor growth, ... more The histone code reader Spindlin1 (SPIN1) has been implicated in tumorigenesis and tumor growth, but the underlying molecular mechanisms remain poorly understood. Here, we show that reducing SPIN1 levels strongly impairs proliferation and increases apoptosis of liposarcoma cells in vitro and in xenograft mouse models. Combining signaling pathway, genome-wide chromatin binding, and transcriptome analyses, we found that SPIN1 directly enhances expression of GDNF, an activator of the RET signaling pathway, in cooperation with the transcription factor MAZ. Accordingly, knockdown of SPIN1 or MAZ results in reduced levels of GDNF and activated RET explaining diminished liposarcoma cell proliferation and survival. In line with these observations, levels of SPIN1, GDNF, activated RET, and MAZ are increased in human liposarcoma compared to normal adipose tissue or lipoma. Importantly, a mutation of SPIN1 within the reader domain interfering with chromatin binding reduces liposarcoma cell pro...

American journal of clinical pathology, 2015

This study examines the expression and the role of four-and-a-half LIM domains protein 2 (FHL2) a... more This study examines the expression and the role of four-and-a-half LIM domains protein 2 (FHL2) and transforming growth factor β1 (TGF-β1) in human malignant melanoma. It is determined whether both proteins influence melanoma survival time. We analyzed the immunohistochemical staining intensities of FHL2 and TGF-β1 in normal skin and in 50 malignant melanomas with different mutation status (BRAF-V600E, NRAS codon 61 mutation, and wild type). Survival data were available for 45 cases. In melanocytes of nonneoplastic human skin, FHL2 expression was absent. In contrast, 38 (76%) of 50 melanomas showed strong cytoplasmic and partly nuclear FHL2 expression. At the invasion front, cytoplasmic TGF-β1 staining was observed in 32 (64%) of 50 melanomas, and a correlation of FHL2 and TGF-β1 staining intensities was detectable. In follow-up analyses, enhanced FHL2 and TGF-β1 staining intensities in the tumor invasion front were associated with poor survival. Enhanced FHL2 and TGF-β1 expression ...

Oncotarget, Jan 30, 2014

The major threat in prostate cancer is the occurrence of metastases in androgen-independent tumor... more The major threat in prostate cancer is the occurrence of metastases in androgen-independent tumor stage, for which no causative cure is available. Here we show that metastatic behavior of androgen-independent prostate tumor cells requires the protein-kinase-C-related kinase (PRK1/PKN1) in vitro and in vivo. PRK1 regulates cell migration and gene expression through its kinase activity, but does not affect cell proliferation. Transcriptome and interactome analyses uncover that PRK1 regulates expression of migration-relevant genes by interacting with the scaffold protein sperm-associated antigen 9 (SPAG9/JIP4). SPAG9 and PRK1 colocalize in human cancer tissue and are required for p38-phosphorylation and cell migration. Accordingly, depletion of either ETS domain-containing protein Elk-1 (ELK1), an effector of p38-signalling or p38 depletion hinders cell migration and changes expression of migration-relevant genes as observed upon PRK1-depletion. Importantly, a PRK1 inhibitor prevents m...

Molecular and cellular biology, 1999

Somatostatin receptor type II expression in the mammalian brain displays a spatially and temporal... more Somatostatin receptor type II expression in the mammalian brain displays a spatially and temporally very restricted pattern. In an investigation of the molecular mechanisms controlling these patterns, we have recently shown that binding of the transcription factor SEF-2 to a novel initiator element in the SSTR-2 promoter is essential for SSTR-2 gene expression. Further characterization of the promoter identified a species-conserved TC-rich enhancer element. By screening a mouse brain cDNA expression library, we cloned a cDNA encoding the transcription factor MIBP1. MIBP1 interacts specifically with both the TC box in the SSTR-2 promoter and with the SEF-2 initiator-binding protein to enhance transcription from the basal SSTR-2 promoter. We then investigated SSTR-2, SEF-2, and MIBP1 mRNA expression patterns in the developing and adult murine brain by Northern blotting and in situ hybridization. While SEF-2 is widely expressed in many neuronal and nonneuronal tissues, MIBP1 expression...

Proceedings of the National Academy of Sciences of the United States of America, 1993

We have isolated a gene coding for a fourth human somatostatin (somatotropin release-inhibiting f... more We have isolated a gene coding for a fourth human somatostatin (somatotropin release-inhibiting factor) receptor. This additional somatostatin receptor (hSSTR4) is specifically expressed in human fetal and adult brain and lung tissue. The deduced amino acid sequence of the receptor displays both sequence and structural homology to three cloned somatostatin receptors as well as to other members of the family of GTP-binding-protein-coupled seven-helix transmembrane-spanning receptors. Pharmacological characterization of the expressed receptor reveals specific, high-affinity binding of somatostatin 14 and somatostatin 28. Surprisingly, several well-characterized synthetic somatostatin analogs fail to exhibit high-affinity binding to hSSTR4, indicating the existence of pharmacologically different receptor subtypes. Our data suggest that the diverse biological effects exerted by somatostatin are mediated by a family of receptors with discrete patterns of expression and different pharmaco...

Pathology - Research and Practice, 2015

Four and a half LIM domain protein-2 (FHL2) is part of the focal adhesion structures modulating c... more Four and a half LIM domain protein-2 (FHL2) is part of the focal adhesion structures modulating cell motility. FHL2 may translocate into the nucleus serving as a transcriptional cofactor binding several transcription factors. Overexpression of FHL2 has been linked to cancer progression in various neoplasias. The aim of the present study was to determine, whether FHL2's function as nuclear cofactor plays a prognostic role in invading tumor cells of sporadic and HNPCC-associated colorectal cancer (CRC). Immunohistochemical staining intensity of nuclear FHL2 was quantified by Remmele score analysing 47 sporadic and 42 HNPCC-associated colorectal cancers. Analysis was restricted to carcinoma cells of the tumoral invasion front. Confocal microscopy detected nuclear expression of FHL2 in colon cancer cells and absence of nuclear FHL2 signal in normal colon enterocytes. In colon cancer, nuclear FHL2 expression was predominantly observed in low-differentiated, often mucinous tumor areas. 42.55% of sporadic and 54.76% of HNPCC-associated CRC showed enhanced (Remmele score 6-12) nuclear FHL2 expression in the carcinoma cells of the tumoral advancing edge. Enhanced nuclear FHL2 expression was significantly linked to lymphatic metastasis in sporadic CRC (p=0.0197) and almost reached significance in HNPCC-associated CRC (p=0.0545). In contrast, nuclear FHL2 expression was neither associated with hematogenic metastasis in sporadic (p=0.7087) nor in HNPCC-associated colorectal cancer (p=0.3007). We recently demonstrated that enhanced nuclear FHL2 expression in tumor stroma of sporadic colon cancer is associated with lymphatic metastasis. The results of the present study indicate a synergistic effect of nuclear cofactor FHL2 in tumor cells as well as in peritumoral stroma cells promoting lymphatic metastasis in sporadic CRC. As HNPCC-associated tumors did not show a significant association between tumoral nuclear FHL2 expression and lymphatic metastasis we speculate, that the intensive lymphocytic immune response in HNPCC precludes a direct contact of tumor cells and stromal cells resulting in reduced lymphatic spread.

Journal of The Society for Gynecologic Investigation, 2006

GBM Annual Spring meeting Mosbach 2008, 2008

Retinoids regulate gene expression through binding to the nuclear retinoic acid receptors (RARs) ... more Retinoids regulate gene expression through binding to the nuclear retinoic acid receptors (RARs) and retinoid X receptors (RXRs). In contrast, no ligands for the retinoic acid receptor-related orphan receptors beta and gamma (ROR beta and gamma) have been identified, yet structural data and structure-function analyses indicate that ROR beta is a ligand-regulated nuclear receptor. Using nondenaturing mass spectrometry and scintillation proximity assays we found that all-trans retinoic acid (ATRA) and several retinoids bind to the ROR beta ligand-binding domain (LBD). The crystal structures of the complex with ATRA and with the synthetic analog ALRT 1550 reveal the binding modes of these ligands. ATRA and related retinoids inhibit ROR beta but not ROR alpha transcriptional activity suggesting that high-affinity, subtype-specific ligands could be designed for the identification of ROR beta target genes. Our results identify ROR beta as a retinoid-regulated nuclear receptor, providing a novel pathway for retinoid action.

Faseb Journal, 2008

The differentiation of bone marrow mes- enchymal stem cells (MSCs) into osteoblasts is a crucial ... more The differentiation of bone marrow mes- enchymal stem cells (MSCs) into osteoblasts is a crucial step in bone formation. However, the mechanisms in- volved in the early stages of osteogenic differentiation are not well understood. In this study, we identified FHL2, a member of the LIM-only subclass of the LIM protein superfamily, that is up-regulated during early osteoblast differentiation induced

Cell reports, Jan 11, 2014

Lysine-Specific Demethylase 1 (LSD1, KDM1A) functions as a transcriptional corepressor through de... more Lysine-Specific Demethylase 1 (LSD1, KDM1A) functions as a transcriptional corepressor through demethylation of histone 3 lysine 4 (H3K4) but has a coactivator function on some genes through mechanisms that are unclear. We show that LSD1, interacting with CoREST, associates with and coactivates androgen receptor (AR) on a large fraction of androgen-stimulated genes. A subset of these AR/LSD1-associated enhancer sites have histone 3 threonine 6 phosphorylation (H3T6ph), and these sites are further enriched for androgen-stimulated genes. Significantly, despite its coactivator activity, LSD1 still mediates H3K4me2 demethylation at these androgen-stimulated enhancers. FOXA1 is also associated with LSD1 at AR-regulated enhancer sites, and a FOXA1 interaction with LSD1 enhances binding of both proteins at these sites. These findings show that LSD1 functions broadly as a regulator of AR function, that it maintains a transcriptional repression function at AR-regulated enhancers through H3K4...

Prostate cancer biology varies from locally confined tumors with low risk for relapse to tumors w... more Prostate cancer biology varies from locally confined tumors with low risk for relapse to tumors with high risk for progression even after radical prostatectomy. Currently, there are no reliable biomarkers to predict tumor relapse and poor clinical outcome. In this study, we correlated expression patterns of the androgen receptor (AR)coactivators lysine- specific histone demethylase 1 (LSD1)and four and a half

Nature Communications, 2014

Molecular Oncology, 2015

EPHB3 is a critical cellular guidance factor in the intestinal epithelium and an important tumor ... more EPHB3 is a critical cellular guidance factor in the intestinal epithelium and an important tumor suppressor in colorectal cancer (CRC) whose expression is frequently lost at the adenoma-carcinoma transition when tumor cells become invasive. The molecular mechanisms underlying EPHB3 silencing are incompletely understood. Here we show that EPHB3 expression is anti-correlated with inducers of epithelial-mesenchymal transition (EMT) in primary tumors and CRC cells. In vitro, SNAIL1 and SNAIL2, but not ZEB1, repress EPHB3 reporter constructs and compete with the stem cell factor ASCL2 for binding to an E-box motif. At the endogenous EPHB3 locus, SNAIL1 triggers the displacement of ASCL2, p300 and the Wnt pathway effector TCF7L2 and engages corepressor complexes containing HDACs and the histone demethylase LSD1 to collapse active chromatin structure, resulting in rapid downregulation of EPHB3. Beyond its impact on EPHB3, SNAIL1 deregulates markers of intestinal identity and stemness and in vitro forces CRC cells to undergo EMT with altered morphology, increased motility and invasiveness. In xenotransplants, SNAIL1 expression abrogated tumor cell palisading and led to focal loss of tumor encapsulation and the appearance of areas with tumor cells displaying a migratory phenotype. These changes were accompanied by loss of EPHB3 and CDH1 expression. Intriguingly, SNAIL1-induced phenotypic changes of CRC cells are significantly impaired by sustained EPHB3 expression both in vitro and in vivo. Altogether, our results identify EPHB3 as a novel target of SNAIL1 and suggest that disabling EPHB3 signaling is an important aspect to eliminate a roadblock at the onset of EMT processes.

The Journal of Cell Biology, 2007

Oncotarget, Jan 20, 2015

A lack of cell surface markers for the specific identification, isolation and subsequent analysis... more A lack of cell surface markers for the specific identification, isolation and subsequent analysis of living prostate tumor cells hampers progress in the field. Specific characterization of tumor cells and their microenvironment in a multi-parameter molecular assay could significantly improve prognostic accuracy for the heterogeneous prostate tumor tissue. Novel functionalized gold-nano particles allow fluorescence-based detection of absolute mRNA expression levels in living cells by fluorescent activated flow cytometry (FACS). We use of this technique to separate prostate tumor and benign cells in human prostate needle biopsies based on the expression levels of the tumor marker alpha-methylacyl-CoA racemase (AMACR). We combined RNA and protein detection of living cells by FACS to gate for epithelial cell adhesion molecule (EPCAM) positive tumor and benign cells, EPCAM/CD45 double negative mesenchymal cells and CD45 positive infiltrating lymphocytes. EPCAM positive epithelial cells w...

Molecular and cellular biology, 1999

The orphan receptor germ cell nuclear factor (GCNF) is a member of the superfamily of nuclear rec... more The orphan receptor germ cell nuclear factor (GCNF) is a member of the superfamily of nuclear receptors. During development, GCNF exhibits a restricted brain-specific expression pattern, whereas GCNF expression in the adult is germ cell specific. Therefore, the receptor may participate in the regulation of neurogenesis and reproductive functions. No natural GCNF target gene has yet been identified, but recent data demonstrate specific and high-affinity binding of GCNF either to the direct repeat DNA element AGGTCAAGGTCA (DR0) or to extended half-sites, such as TCAAGGTCA. In this study, we show that murine GCNF (mGCNF) can bind as a homodimer to extended half-sites, thus describing a novel property within the nuclear receptor superfamily. Homodimeric binding to extended half-sites requires the presence of a dimerization function within the mGCNF DNA-binding domain (DBD) and a novel dimerization surface encompassing the putative helix 3 and the helix 12 region of the mGCNF ligand-bind...

Oncotarget, Jan 10, 2015

The histone code reader Spindlin1 (SPIN1) has been implicated in tumorigenesis and tumor growth, ... more The histone code reader Spindlin1 (SPIN1) has been implicated in tumorigenesis and tumor growth, but the underlying molecular mechanisms remain poorly understood. Here, we show that reducing SPIN1 levels strongly impairs proliferation and increases apoptosis of liposarcoma cells in vitro and in xenograft mouse models. Combining signaling pathway, genome-wide chromatin binding, and transcriptome analyses, we found that SPIN1 directly enhances expression of GDNF, an activator of the RET signaling pathway, in cooperation with the transcription factor MAZ. Accordingly, knockdown of SPIN1 or MAZ results in reduced levels of GDNF and activated RET explaining diminished liposarcoma cell proliferation and survival. In line with these observations, levels of SPIN1, GDNF, activated RET, and MAZ are increased in human liposarcoma compared to normal adipose tissue or lipoma. Importantly, a mutation of SPIN1 within the reader domain interfering with chromatin binding reduces liposarcoma cell pro...

American journal of clinical pathology, 2015

This study examines the expression and the role of four-and-a-half LIM domains protein 2 (FHL2) a... more This study examines the expression and the role of four-and-a-half LIM domains protein 2 (FHL2) and transforming growth factor β1 (TGF-β1) in human malignant melanoma. It is determined whether both proteins influence melanoma survival time. We analyzed the immunohistochemical staining intensities of FHL2 and TGF-β1 in normal skin and in 50 malignant melanomas with different mutation status (BRAF-V600E, NRAS codon 61 mutation, and wild type). Survival data were available for 45 cases. In melanocytes of nonneoplastic human skin, FHL2 expression was absent. In contrast, 38 (76%) of 50 melanomas showed strong cytoplasmic and partly nuclear FHL2 expression. At the invasion front, cytoplasmic TGF-β1 staining was observed in 32 (64%) of 50 melanomas, and a correlation of FHL2 and TGF-β1 staining intensities was detectable. In follow-up analyses, enhanced FHL2 and TGF-β1 staining intensities in the tumor invasion front were associated with poor survival. Enhanced FHL2 and TGF-β1 expression ...

Oncotarget, Jan 30, 2014

The major threat in prostate cancer is the occurrence of metastases in androgen-independent tumor... more The major threat in prostate cancer is the occurrence of metastases in androgen-independent tumor stage, for which no causative cure is available. Here we show that metastatic behavior of androgen-independent prostate tumor cells requires the protein-kinase-C-related kinase (PRK1/PKN1) in vitro and in vivo. PRK1 regulates cell migration and gene expression through its kinase activity, but does not affect cell proliferation. Transcriptome and interactome analyses uncover that PRK1 regulates expression of migration-relevant genes by interacting with the scaffold protein sperm-associated antigen 9 (SPAG9/JIP4). SPAG9 and PRK1 colocalize in human cancer tissue and are required for p38-phosphorylation and cell migration. Accordingly, depletion of either ETS domain-containing protein Elk-1 (ELK1), an effector of p38-signalling or p38 depletion hinders cell migration and changes expression of migration-relevant genes as observed upon PRK1-depletion. Importantly, a PRK1 inhibitor prevents m...

Molecular and cellular biology, 1999

Somatostatin receptor type II expression in the mammalian brain displays a spatially and temporal... more Somatostatin receptor type II expression in the mammalian brain displays a spatially and temporally very restricted pattern. In an investigation of the molecular mechanisms controlling these patterns, we have recently shown that binding of the transcription factor SEF-2 to a novel initiator element in the SSTR-2 promoter is essential for SSTR-2 gene expression. Further characterization of the promoter identified a species-conserved TC-rich enhancer element. By screening a mouse brain cDNA expression library, we cloned a cDNA encoding the transcription factor MIBP1. MIBP1 interacts specifically with both the TC box in the SSTR-2 promoter and with the SEF-2 initiator-binding protein to enhance transcription from the basal SSTR-2 promoter. We then investigated SSTR-2, SEF-2, and MIBP1 mRNA expression patterns in the developing and adult murine brain by Northern blotting and in situ hybridization. While SEF-2 is widely expressed in many neuronal and nonneuronal tissues, MIBP1 expression...

Proceedings of the National Academy of Sciences of the United States of America, 1993

We have isolated a gene coding for a fourth human somatostatin (somatotropin release-inhibiting f... more We have isolated a gene coding for a fourth human somatostatin (somatotropin release-inhibiting factor) receptor. This additional somatostatin receptor (hSSTR4) is specifically expressed in human fetal and adult brain and lung tissue. The deduced amino acid sequence of the receptor displays both sequence and structural homology to three cloned somatostatin receptors as well as to other members of the family of GTP-binding-protein-coupled seven-helix transmembrane-spanning receptors. Pharmacological characterization of the expressed receptor reveals specific, high-affinity binding of somatostatin 14 and somatostatin 28. Surprisingly, several well-characterized synthetic somatostatin analogs fail to exhibit high-affinity binding to hSSTR4, indicating the existence of pharmacologically different receptor subtypes. Our data suggest that the diverse biological effects exerted by somatostatin are mediated by a family of receptors with discrete patterns of expression and different pharmaco...

Pathology - Research and Practice, 2015

Four and a half LIM domain protein-2 (FHL2) is part of the focal adhesion structures modulating c... more Four and a half LIM domain protein-2 (FHL2) is part of the focal adhesion structures modulating cell motility. FHL2 may translocate into the nucleus serving as a transcriptional cofactor binding several transcription factors. Overexpression of FHL2 has been linked to cancer progression in various neoplasias. The aim of the present study was to determine, whether FHL2's function as nuclear cofactor plays a prognostic role in invading tumor cells of sporadic and HNPCC-associated colorectal cancer (CRC). Immunohistochemical staining intensity of nuclear FHL2 was quantified by Remmele score analysing 47 sporadic and 42 HNPCC-associated colorectal cancers. Analysis was restricted to carcinoma cells of the tumoral invasion front. Confocal microscopy detected nuclear expression of FHL2 in colon cancer cells and absence of nuclear FHL2 signal in normal colon enterocytes. In colon cancer, nuclear FHL2 expression was predominantly observed in low-differentiated, often mucinous tumor areas. 42.55% of sporadic and 54.76% of HNPCC-associated CRC showed enhanced (Remmele score 6-12) nuclear FHL2 expression in the carcinoma cells of the tumoral advancing edge. Enhanced nuclear FHL2 expression was significantly linked to lymphatic metastasis in sporadic CRC (p=0.0197) and almost reached significance in HNPCC-associated CRC (p=0.0545). In contrast, nuclear FHL2 expression was neither associated with hematogenic metastasis in sporadic (p=0.7087) nor in HNPCC-associated colorectal cancer (p=0.3007). We recently demonstrated that enhanced nuclear FHL2 expression in tumor stroma of sporadic colon cancer is associated with lymphatic metastasis. The results of the present study indicate a synergistic effect of nuclear cofactor FHL2 in tumor cells as well as in peritumoral stroma cells promoting lymphatic metastasis in sporadic CRC. As HNPCC-associated tumors did not show a significant association between tumoral nuclear FHL2 expression and lymphatic metastasis we speculate, that the intensive lymphocytic immune response in HNPCC precludes a direct contact of tumor cells and stromal cells resulting in reduced lymphatic spread.

Journal of The Society for Gynecologic Investigation, 2006

GBM Annual Spring meeting Mosbach 2008, 2008

Retinoids regulate gene expression through binding to the nuclear retinoic acid receptors (RARs) ... more Retinoids regulate gene expression through binding to the nuclear retinoic acid receptors (RARs) and retinoid X receptors (RXRs). In contrast, no ligands for the retinoic acid receptor-related orphan receptors beta and gamma (ROR beta and gamma) have been identified, yet structural data and structure-function analyses indicate that ROR beta is a ligand-regulated nuclear receptor. Using nondenaturing mass spectrometry and scintillation proximity assays we found that all-trans retinoic acid (ATRA) and several retinoids bind to the ROR beta ligand-binding domain (LBD). The crystal structures of the complex with ATRA and with the synthetic analog ALRT 1550 reveal the binding modes of these ligands. ATRA and related retinoids inhibit ROR beta but not ROR alpha transcriptional activity suggesting that high-affinity, subtype-specific ligands could be designed for the identification of ROR beta target genes. Our results identify ROR beta as a retinoid-regulated nuclear receptor, providing a novel pathway for retinoid action.

Faseb Journal, 2008

The differentiation of bone marrow mes- enchymal stem cells (MSCs) into osteoblasts is a crucial ... more The differentiation of bone marrow mes- enchymal stem cells (MSCs) into osteoblasts is a crucial step in bone formation. However, the mechanisms in- volved in the early stages of osteogenic differentiation are not well understood. In this study, we identified FHL2, a member of the LIM-only subclass of the LIM protein superfamily, that is up-regulated during early osteoblast differentiation induced

Cell reports, Jan 11, 2014

Lysine-Specific Demethylase 1 (LSD1, KDM1A) functions as a transcriptional corepressor through de... more Lysine-Specific Demethylase 1 (LSD1, KDM1A) functions as a transcriptional corepressor through demethylation of histone 3 lysine 4 (H3K4) but has a coactivator function on some genes through mechanisms that are unclear. We show that LSD1, interacting with CoREST, associates with and coactivates androgen receptor (AR) on a large fraction of androgen-stimulated genes. A subset of these AR/LSD1-associated enhancer sites have histone 3 threonine 6 phosphorylation (H3T6ph), and these sites are further enriched for androgen-stimulated genes. Significantly, despite its coactivator activity, LSD1 still mediates H3K4me2 demethylation at these androgen-stimulated enhancers. FOXA1 is also associated with LSD1 at AR-regulated enhancer sites, and a FOXA1 interaction with LSD1 enhances binding of both proteins at these sites. These findings show that LSD1 functions broadly as a regulator of AR function, that it maintains a transcriptional repression function at AR-regulated enhancers through H3K4...

Prostate cancer biology varies from locally confined tumors with low risk for relapse to tumors w... more Prostate cancer biology varies from locally confined tumors with low risk for relapse to tumors with high risk for progression even after radical prostatectomy. Currently, there are no reliable biomarkers to predict tumor relapse and poor clinical outcome. In this study, we correlated expression patterns of the androgen receptor (AR)coactivators lysine- specific histone demethylase 1 (LSD1)and four and a half

Nature Communications, 2014

Molecular Oncology, 2015

EPHB3 is a critical cellular guidance factor in the intestinal epithelium and an important tumor ... more EPHB3 is a critical cellular guidance factor in the intestinal epithelium and an important tumor suppressor in colorectal cancer (CRC) whose expression is frequently lost at the adenoma-carcinoma transition when tumor cells become invasive. The molecular mechanisms underlying EPHB3 silencing are incompletely understood. Here we show that EPHB3 expression is anti-correlated with inducers of epithelial-mesenchymal transition (EMT) in primary tumors and CRC cells. In vitro, SNAIL1 and SNAIL2, but not ZEB1, repress EPHB3 reporter constructs and compete with the stem cell factor ASCL2 for binding to an E-box motif. At the endogenous EPHB3 locus, SNAIL1 triggers the displacement of ASCL2, p300 and the Wnt pathway effector TCF7L2 and engages corepressor complexes containing HDACs and the histone demethylase LSD1 to collapse active chromatin structure, resulting in rapid downregulation of EPHB3. Beyond its impact on EPHB3, SNAIL1 deregulates markers of intestinal identity and stemness and in vitro forces CRC cells to undergo EMT with altered morphology, increased motility and invasiveness. In xenotransplants, SNAIL1 expression abrogated tumor cell palisading and led to focal loss of tumor encapsulation and the appearance of areas with tumor cells displaying a migratory phenotype. These changes were accompanied by loss of EPHB3 and CDH1 expression. Intriguingly, SNAIL1-induced phenotypic changes of CRC cells are significantly impaired by sustained EPHB3 expression both in vitro and in vivo. Altogether, our results identify EPHB3 as a novel target of SNAIL1 and suggest that disabling EPHB3 signaling is an important aspect to eliminate a roadblock at the onset of EMT processes.

The Journal of Cell Biology, 2007