Expression Of Lymphoid Enhancer-binding Factor 1 Research Articles

Bromuconazole exposure induces cardiac dysfunction by upregulating the expression LEF1

With the wide application of bromuconazole (BRO), a kind of triazole fungicide, the environmental problems caused by BRO have been paid more and more attention. In this study, adult male zebrafish were exposed to environmental related concentration and the maximum non-lethal concentration for zebrafish larvae (0,50 ng/L and 7.5 mg/L) for 7 days, respectively. Zebrafish exposed to BRO exhibited a significant reduction in body length and an increase in fatness index, indicating adverse physiological changes. Notably, the exposed zebrafish showed enlarged heart ventricular volumes and thinner heart walls. Transcriptome analysis of heart samples showed that BRO exposure mainly affected pathways related to cardiac energy metabolism. In addition, the amount of ATP in the heart tissue was correspondingly reduced, and the expression levels of genes related to controlling ion balance and myosin synthesis in the heart were also altered. The study extended its findings to the rat cardiomyocytes (H9C2), where similar cardiotoxic effects including changes in transcription of genes related to energy metabolism and heart function were also observed, suggesting a potential universal mechanism of BRO-induced cardiotoxicity. In a doxorubicin (DOX) induced larval zebrafish heart failure model, the expression of lymphoid enhancer-binding factor 1(LEF1), a key gene in the Wnt/β-catenin signaling pathway, was significantly increased in larval zebrafish and adult fish heart tissues and cardiomyocytes, suggesting that LEF1 might play an important role in BRO-induced cardiotoxicity. Taken together, BRO exposure could interfere with cardiac function and metabolic capacity by abnormal activation the expression of LEF1. The study emphasized the urgent need for monitoring and regulating BRO due to its harmful effects on the hearts of aquatic organisms.

DNA Damage-Induced Apoptosis Suppressor Triggers Progression and Stemness of Glioma by Enhancing Lymphoid Enhancer-Binding Factor 1 Expression.

DNA damage-induced apoptosis suppressor (DDIAS) has recently been discovered to induce cancer progression, but its functions and mechanisms in glioma have not been well studied. DDIAS expression in glioma tissues was analyzed by the Gene Expression Profiling Interactive Analysis server (GEPIA) and the Gene Expression database of Normal and Tumor tissue 2 (GENT2) databases. The role of DDIAS in glioma progression was studied by short hairpin RNA (shRNA) targeting DDIAS. The effects of DDIAS on glioma cell viability, cell proliferation, invasion, migration, and tumor sphere formation were determined by cell counting kit-8 (CCK-8), EdU, Transwell, tumor spheroid formation, extreme limiting dilution analysis assays in vitro and xenograft model construction in vivo. In addition, RNA sequencing and further functional experiments were used to analyze the DDIAS regulatory mechanism in glioma. We found that DDIAS was highly expressed in glioma and that upregulated DDIAS indicated poor prognosis. Functionally, DDIAS knockdown inhibited glioma cell viability, cell proliferation, invasion and migration in vitro and tumor growth in vivo. In addition, lymphoid enhancer-binding factor 1 (LEF1) was identified as the downstream effector of DDIAS by RNA sequencing. DDIAS downregulation inhibited LEF1 mRNA and protein expression. The expression of DDIAS and LEF1 was positively correlated, and LEF1 overexpression rescued the inhibitory phenotype induced by DDIAS downregulation. We further showed that DDIAS downregulation inhibited cyclin A1, vimentin and the stemness-related factor CD133 and decreased the sphere formation capability, but these features were rescued by upregulation of LEF1. Taken together, these findings suggest that DDIAS promotes glioma progression and stemness by inducing LEF1 expression, proving that DDIAS may be a potential target for the treatment of glioma.

DPPA2/4 Promote the Pluripotency and Proliferation of Bovine Extended Pluripotent Stem Cells by Upregulating the PI3K/AKT/GSK3β/β-Catenin Signaling Pathway.

Developmental pluripotency-associated 2 (DPPA2) and DPPA4 are crucial transcription factors involved in maintaining pluripotency in humans and mice. However, the role of DPPA2/4 in bovine extended pluripotent stem cells (bEPSCs) has not been investigated. In this study, a subset of bEPSC-related differentially expressed genes (DEGs), including DPPA2 and DPPA4, was identified based on multiomics data (ATAC-seq and RNA-seq). Subsequent investigations revealed that double overexpression of DPPA2/4 facilitates the reprogramming of bovine fetal fibroblasts (BFFs) into bEPSCs, whereas knockout of DPPA2/4 in BFFs leads to inefficient reprogramming. DPPA2/4 overexpression and knockdown experiments revealed that the pluripotency and proliferation capability of bEPSCs were maintained by promoting the transition from the G1 phase to the S phase of the cell cycle. By activating the PI3K/AKT/GSK3β/β-catenin pathway in bEPSCs, DPPA2/4 can increase the nuclear accumulation of β-catenin, which further upregulates lymphoid enhancer binding factor 1 (LEF1) transcription factor activity. Moreover, DPPA2/4 can also regulate the expression of LEF1 by directly binding to its promoter region. Overall, our results demonstrate that DPPA2/4 promote the reprogramming of BFFs into bEPSCs while also maintaining the pluripotency and proliferation capability of bEPSCs by regulating the PI3K/AKT/GSK3β/β-catenin pathway and subsequently activating LEF1. These findings expand our understanding of the gene regulatory network involved in bEPSC pluripotency.

FOXO1 promotes the expression of canonical WNT target genes in examined basal-like breast and glioblastoma multiforme cancer cells.

Basal-like breast cancer (BBC) and glioblastoma multiforme (GBM) are aggressive cancers associated with poor prognosis. BBC and GBM have stem cell-like gene expression signatures, which are in part driven by forkhead box O (FOXO) transcription factors. To gain further insight into the impact of FOXO1 in BBC, we treated BT549 cells with AS1842856 and performed RNA sequencing. AS1842856 binds to unphosphorylated FOXO1 and inhibits its ability to directly bind to DNA. Gene Set Enrichment Analysis indicated that a set of WNT pathway target genes, including lymphoid enhancer-binding factor 1 (LEF1) and transcription factor 7 (TCF7), were robustly induced after AS1842856 treatment. These same genes were also induced in GBM cell lines U87MG, LN18, LN229, A172, and DBTRG upon AS1842856 treatment. By contrast, follow-up RNA interference (RNAi) targeting of FOXO1 led to reduced LEF1 and TCF7 gene expression in BT549 and U87MG cells. In agreement with RNAi experiments, CRISPR Cas9-mediated FOXO1 disruption reduced the expression of canonical WNT genes LEF1 and TCF7 in U87MG cells. The loss of TCF7 gene expression in FOXO1 disruption mutants was restored by exogenous expression of the DNA-binding-deficient FOXO1-H215R. Therefore, FOXO1 induces TCF7 in a DNA-binding-independent manner, similar to other published FOXO1-activated genes such as TCF4 and hes family bHLH transcription factor 1. Our work demonstrates that FOXO1 promotes canonical WNT gene expression in examined BBC and GBM cells, similar to results found in Drosophila melanogaster, T-cell development, and murine acute myeloid leukemia models.

PRAME and LEF1 in Combined Deep Penetrating Nevus and Combined Blue Nevus: Utility and Pitfalls.

Deep penetrating nevi (DPN), particularly those showing combined features, or combined deep penetrating nevi (CDPN), may show histopathological resemblance to blue nevus (BN) and melanoma. Preferentially Expressed Antigen in MElanoma (PRAME) is a marker that helps distinguish melanoma from benign melanocytic lesions. Lymphoid enhancer-binding factor 1 (LEF1) has been proposed to be used in conjunction with β-catenin for diagnosis of DPN. The immunohistochemical expression of PRAME and LEF1 was evaluated in 10 DPN (including 6 CDPN and 2 DPN-like proliferations with atypical features), 16 BN (including combined and cellular BN), and 2 melanomas with features of DPN or BN. PRAME was negative in most DPN (n = 10/10, n = 9/10, one case with discrepancy between readers) and all BN (n = 16/16), while the 2 melanomas included were positive (n = 2/2). All DPN were positive for LEF1 (n = 9/9) while only a subset of BN were positive (n = 6/16, P = 0.0028; n = 5/16, P = 0.001, per both readers). LEF1 seemed to be easier to interpret than β-catenin because of its nuclear pattern of expression. The expression of LEF1 in the regular nevus component of combined BN presents a potential pitfall in practice because it may lead to misinterpretation of LEF1 as positive in the BN component of the lesion. However, a subset (approximately one-third) of combined BN seemed to show true LEF1 expression. Taking into account pitfalls in interpretation, the combinatorial panel of PRAME and LEF1, in addition to conventional histopathological features, may be useful to distinguish CDPN from combined BN and other benign and malignant mimics.

The Prognostic and Drug-targeting Value of Lymphoid Enhancer-binding Factor-1 in Hepatocellular Carcinoma.

Lymphoid Enhancer-Binding Factor-1 (LEF1) was previously reported to contribute to a variety of malignancies, including Hepatocellular Carcinoma (HCC). However, its role in HCC is poorly understood. To explore the role of LEF1 in HCC, including its prognostic and drug-targeting value. The LEF1 expression and patient characteristics were investigated. The associations between clinical characteristics and LEF1 were analyzed using both univariate and multivariate logistic regression. Cox regression and Kaplan-Meier curves were used to explore the clinicopathological factors related to overall survival in patients with HCC. A nomogram to predict the survival rate was constructed and validated. The Kyoto Encyclopedia of Genes and Genomes database (KEGG) was used to explore the function of LEF1. Gene Set Enrichment Analysis (GSEA) was also performed using The Cancer Genome Atlas dataset. Furthermore, compounds that may have the potential to be targeted drugs in the treatment of LEF1-overexpressing HCC were identified using the Comparative Toxicogenomics Database (CTD), patents about these drugs in HCC were also reviewed through Worldwide Espacenet® and Patentscope®. Increased expression of LEF1 was significantly associated with high histological grade of HCC (odds ratio (OR) = 2.521 for grade (G) 2 vs. G1, OR = 2.550 for G3 vs. G1, OR = 7.081 for G4 vs. G1, all P < 0.05). A Kaplan-Meier survival curve showed that HCC patients with LEF1 overexpression had a poor prognosis compared with those with normal LEF1 expression (P = 0.025). Multivariate Cox regression analysis revealed that LEF1 is an independent prognostic factor for the overall survival of patients with HCC (Hazard Ratio (HR) = 1.095; P = 0.04). The constructed nomogram to predict the survival rate produced a statistically significant prediction (area under the curve (AUC) = 86.68). In addition, Gene Ontology (GO) and KEGG analysis of genes co-expressed with the protein showed that LEF1 was associated with transcriptional regulation. GSEA suggested that the cell cycle, the WNT signaling pathway, and the NOTCH signaling pathway may be the key pathways regulated by LEF1 in HCC. Furthermore, the Comparative Toxicogenomics Database (CTD) identified nine compounds that may have the potential to be targeted drugs in the treatment of LEF1-overexpressing HCC. Patent reviews suggested that these drugs may show some efficacy in HCC, but whether these drugs interact with LEF1 and improve the prognosis for patients with HCC remains to be explored. LEF1 is a latent prognostic molecular biomarker of HCC. The cell cycle, and WNT and NOTCH signaling pathways are regulated by LEF1 in HCC. LEF1 could be a potential drug target for HCC.

Water extract of cacumen platycladi promotes hair growth through the Akt/GSK3β/β-catenin signaling pathway.

Cacumen Platycladi (CP) consists of the dried needles of Platycladus orientalis L.) Franco. It was clinically demonstrated that it effectively regenerates hair, but the underlying mechanism remains unknown. Thus, we employed shaved mice to verify the hair growth-promoting capability of the water extract of Cacumen Platycladi (WECP). The morphological and histological analyses revealed that WECP application could significantly promote hair growth and hair follicles (HFs) construction, in comparison to that of control group. Additionally, the skin thickness and hair bulb diameter were significantly increased by the application of WECP in a dose-dependent manner. Besides, the high dose of WECP also showed an effect similar to that of finasteride. In an in vitro assay, WECP stimulated dermal papilla cells (DPCs) proliferation and migration. Moreover, the upregulation of cyclins (cyclin D1, cyclin-dependent kinase 2 (CDK2), and cyclin-dependent kinase 4 (CDK4)) and downregulation of P21 in WECP-treated cell assays have been evaluated. We identified the ingredients of WECP using ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF-MS) and endeavored to predict their relevant molecular mechanisms by network analysis. We found that the Akt (serine/threonine protein kinase) signaling pathway might be a crucial target of WECP. It has been demonstrated that WECP treatment activated the phosphorylation of Akt and glycogen synthase kinase-3-beta (GSK3β), promoted β-Catenin and Wnt10b accumulation, and upregulated the expression of lymphoid enhancer-binding factor 1 (LEF1), vascular endothelial growth factor (VEGF), and insulin-like growth factor 1 (IGF1). We also found that WECP significantly altered the expression levels of apoptosis-related genes in mouse dorsal skin. The enhancement capability of WECP on DPCs proliferation and migration could be abrogated by the Akt-specific inhibitor MK-2206 2HCl. These results suggested that WECP might promote hair growth by modulating DPCs proliferation and migration through the regulation of the Akt/GSK3β/β-Catenin signaling pathway.

Increased Expression of LEF1 and β-Catenin in Invasive Micropapillary Carcinoma of the Breast is Associated With Lymphovascular Invasion and Lymph Node Metastasis.

Invasive micropapillary breast carcinoma (IMPC) is a rare breast cancer subtype characterized by small tumor cell clusters with loss of stromal attachment, an inside-out growth appearance, and lymphotropism. IMPC is associated with high incidence of lymphovascular invasion (LVI) and lymph node metastasis. Activated Wnt signaling has been implicated in the metastasis of other aggressive breast tumors, including triple-negative and basal-like carcinomas. In this study, we tested whether activated Wnt signaling could be detected in IMPC. Upon ligand binding, the central mediator of the Wnt pathway, β-catenin, accumulates in the cytosol and translocates to the nucleus where it forms a complex with lymphoid enhancer-binding factor 1 (LEF1) to regulate transcription. We performed immunostaining for β-catenin and LEF1 on a well-annotated cohort of 40 breast tumors and nodal metastases displaying micropapillary histopathology. Strong nuclear accumulation of β-catenin was not observed, however a dim cytosolic and/or nuclear accumulation of β-catenin was sometimes seen in IMPC and this expression pattern was significantly associated with nodal metastasis. β-catenin expression correlated with the upregulation of LEF1 in IMPC. LEF1 expression was detected in 26 of 40 (65%) cases and was specifically enriched at the invasive front of the tumor and in tumor clusters undergoing LVI. Detection of LEF1 expression in the primary tumor was associated with an increased rate of LVI, lymph node metastasis, and disease relapse. LEF1 and β-catenin expression levels were significantly higher in metastases compared with primary tumors. In summary, this study demonstrates an association between the upregulation of β-catenin/LEF1 and the metastasis of IMPC.

Loss of LEF-1 expression as a diagnostic indicator for extranodal NK/T-cell lymphoma: An immunohistochemical study of 88 cases.

Extranodal natural killer (NK)/T-cell lymphoma (ENKTL) is not a uniform entity but consists of various disease subtypes associated with Epstein-Barr virus (EBV) infection. Lymphoid enhancer binding factor-1 (LEF-1), a member of the T-cell factor/LEF family of transcription factors, plays a significant role in NK-cell and T-cell development. We aimed to explore the expression of LEF-1 in ENKTL and evaluate the applicability of LEF-1 in the diagnosis of ENKTL. The expression of LEF-1 was investigated in tissue samples harvested from patients with ENKTL by immunohistochemistry. LEF-1 staining was not observed in 85 of 88 ENKTL cases (97%). Eighty-six of the 88 cases (98%) were positive for CD56, whereas all the tested cases were negative for both CD16 and CD27. Of the cytotoxic T-cell-like features studied, 81 cases (92%) were negative for CD8, 85 of 88 cases (97%) were immunoreactive for the recombinant linker for activation of T cells (LAT), all (100%) were immunoreactive for TIA-1, 85 (97%) were immunoreactive for granzyme B and 65 (74%) were immunoreactive for perforin. Loss of LEF-1 expression is a highly specific diagnostic indicator of ENKTL.

Niche formed by bone morphogenetic protein antagonists gremlin 1 and gremlin 2 in human hair follicles.

Niche formed by bone morphogenetic protein antagonists gremlin 1 and gremlin 2 in human hair follicles.

Common Gene Expression Signature of B-Cells of Waldenström Macroglobulinemia (WM) and IgM Monoclonal Gammopathies of Undetermined Significance (IgM MGUS) Compared to Healthy Subjects

We performed a comparative gene expression profiling (GEP) study on B-cells and plasma cells of Waldenström Macroglobulinemia (WM), IgM monoclonal gammopathies of undetermined significance (IgMMGUS), and normal individuals (CTRLs) to identify GEP changes as reliable predictors of progression of IgMMGUS to WM.We analyzed bone marrow B-cells and plasma cells from 36 WM patients, 13 IgMMGUS subjects, and 7 CTRLs by Affymetrix microarray, respectively (Table 1). GEP experiments were performed on the CD19+ and CD138+ cells using GeneChip-HGU133 Plus 2.0. Data were preprocessed and normalized by Robust Multi-Array Average and ComBat. Selection of the different expressed genes was performed separately for CD19+ and CD138+ cells, using Significance Analysis of Microarrays (SAM) on the 3 groups and a false discovery rate threshold of 5%, followed, for significance comparisons, by a pair-wise SAM test corrected for multiple testing.We focused on the comparison of the CD19+ cells of WM vs. IgMMGUS vs. CTRLs which highlighted 2038 unique genes whereas the same comparison of the CD138+ cells determined 29 unique genes (Trojani et.al. Cancers 2021). Among the 2038 DEGs, 115 genes were grouped in KEGG pathways involved in Wnt-signaling, BCR-signaling, calcium signaling, hematopoietic cell antigens, cell adhesion, adherens junctions, coagulation cascade, platelet activation, cytokine receptor, and signaling pathways responsible for cell cycle, apoptosis, and survival.Interestingly, most of the 115 DEGs in B-cells were different expressed in WM vs. IgMMGUS and CTRLs. Only 9/115 DEGs were significantly different expressed in WM vs. CTRLs and in IgMMGUS vs. CTRLs, but no significant expression changes were noted between WM and IgMMGUS (Table 2).To further inspect the similarities and the differences among WM and IgMMGUS, we computed the Euclidean pair-wise distance between subjects and, using this distance as weight, constructed a minimum spanning tree (MST) (Figure 1).Considerably, four probesets identified ADRB2 (transmembrane Beta adrenergic receptor) which was up regulated in WM and IgMMGUS compared to CTRLs. The over expression of ADRB2 was also demonstrated in Mantle Cell Lymphoma cell lines and in Diffuse large B-cell lymphoma (DLBCL) lymphocytes compared to normal B-cells (doi10.1016/j.cellsig.2017.08.002), and in most malignancies (doi10.1007/s11033-021-06250-y) .As far as we know, ADAM23 (ADAM Metallopeptidase Domain23) has not been found in WM, whereas we suggest its possible role in WM patients with Sjogren's syndrome (SS). ADAM23 plays a role in the peripheral neuropathy by controlling the activity of potassium channels in SS (doi10.1007/s10067-016-3499-z). Some authors found that sensory/motor neuropathies were associated with MGUS patients (doi10.1017/s0317167100011483). We strongly believe that the down regulation of ADAM23 in WM and IgMMGUS has a good chance to be associated with clinical neuropathy in WM and IgMMGUS.RASGRP3 (RAS Guanyl Releasing Protein3) and PIK3AP1 (Phosphoinositide 3 Kinase Adaptor Protein1) play crucial roles in BCR signaling pathway: PIK3AP1 activates the PI3K-Akt signaling while RASGRP3 stimulates MAPK signaling pathway.The deregulation of LEF1 (Lymphoid Enhancer Binding Factor1) and genes of Wnt-pathway were previously demonstrated in B-cell disorders and multiple myeloma (doi10.1007/s00277-017-3207-3, doi10.1016/j.pathol.2019.09.009). According to these studies, we showed the under expression of LEF1 in WM and IgMMGUS compared to CTRLs.We identified the down regulation of EZH2 (Enhancer Of Zeste2 Polycomb Repressive Complex2Subunit) in WM and IgMMGUS compared to CTRLs. EZH2 is involved in Follicular lymphoma and DLBCL (doi10.1080/2162402X.2017.1321184).CDHR3 (Cadherin Related Family Member3), CHEK1 (Checkpoint Kinase1), and HIST1H1B (Histone-H1.5) were over expressed in CTRLs compared to IgMMGUS and WM.In conclusion, the common gene-set in WM and IgMMGUS could suggest two-hit hypothesis. First, the gene-set could play a role in the risk of progression of IgMMGUS to WM. Until now, all the IgMMGUS subjects have not been transformed in WM or other NHL, but they have been monitored every 6 months, and their possible transformation to lymphoma could highlight new insights. The second hypothesis suggests their involvement in the biological processes of leukemogenesis in WM and IgMMGUS which will be further investigated. [Display omitted] DisclosuresTedeschi: AbbVie: Honoraria, Speakers Bureau; AstraZeneca: Honoraria, Speakers Bureau; Beigene: Honoraria, Speakers Bureau; Janssen: Honoraria, Speakers Bureau.

Screening and Identification of Key Biomarkers of Gastric Cancer: Three Genes Jointly Predict Gastric Cancer.

BackgroundGastric cancer (GC) is one of the most common cancers all over the world, causing high mortality. Gastric cancer screening is one of the effective strategies used to reduce mortality. We expect that good biomarkers can be discovered to diagnose and treat gastric cancer as early as possible.MethodsWe download four gene expression profiling datasets of gastric cancer (GSE118916, GSE54129, GSE103236, GSE112369), which were obtained from the Gene Expression Omnibus (GEO) database. The differentially expressed genes (DEGs) between gastric cancer and adjacent normal tissues were detected to explore biomarkers that may play an important role in gastric cancer. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of overlap genes were conducted by the Metascape online database; the protein-protein interaction (PPI) network was constructed by the STRING online database, and we screened the hub genes of the PPI network using the Cytoscape software. The survival curve analysis was conducted by km-plotter and the stage plots of hub genes were created by the GEPIA online database. PCR, WB, and immunohistochemistry were used to verify the expression of hub genes. A neural network model was established to quantify the predictors of gastric cancer.ResultsThe relative expression level of cadherin-3 (CDH3), lymphoid enhancer-binding factor 1 (LEF1), and matrix metallopeptidase 7 (MMP7) were significantly higher in gastric samples, compared with the normal groups (p<0.05). Receiver operator characteristic (ROC) curves were constructed to determine the effect of the three genes’ expression on gastric cancer, and the AUC was used to determine the degree of confidence: CDH3 (AUC = 0.800, P<0.05, 95% CI =0.857-0.895), LEF1 (AUC=0.620, P<0.05, 95%CI=0.632-0.714), and MMP7 (AUC=0.914, P<0.05, 95%CI=0.714-0.947). The high-risk warning indicator of gastric cancer contained 8<CDH3<15 and 10<expression of LEF1<16.ConclusionsCDH3, LEF1, and MMP7 can be used as candidate biomarkers to construct a neural network model from hub genes, which may be helpful for the early diagnosis of gastric cancer.

Downregulation of LEF1 Impairs Myeloma Cell Growth Through Modulating CYLD/NF-κB Signaling.

Aberrant expression of lymphoid enhancer-binding factor-1 (LEF1) has been identified in various hematological malignancies including multiple myeloma (MM). However, the exact role of LEF1 in MM remains largely unknown. Here, we showed that knockdown of LEF1 could apparently impair the proliferation, induce apoptosis and promote the ROS production in MM cell lines, suggesting that LEF1 might be involved in maintaining MM cell growth and survival. Moreover, we observed that the mRNA level of the deubiquitinase cylindromatosis (CYLD), a well-recognized tumor suppressor in MM, was significantly increased following LEF1 depletion in myeloma cells. Further study showed that LEF1 could directly associate with the promoter of CYLD gene and thus repress its transcription in MM cells. Intriguingly, LEF1 depletion-mediated CYLD upregulation was sufficient to negatively modulate NF-κB signaling pathway in MM cells. Moreover, the decrease in NF-κB activity following LEF1 knockdown could be largely rescued when CYLD was silenced in MM cells. Taken together, our study provided the compelling evidence to show that LEF1 may augment the proliferation and survival of MM cells through direct repression of CYLD transcription and subsequent activation of NF-κB signaling pathway, corroborating that LEF1 may become a potential therapeutic target against MM.

Hepatocyte nuclear factor 1β suppresses canonical Wnt signaling through transcriptional repression of lymphoid enhancer–binding factor 1

Hepatocyte nuclear factor-1β (HNF-1β) is a tissue-specific transcription factor that is required for normal kidney development and renal epithelial differentiation. Mutations of HNF-1β produce congenital kidney abnormalities and inherited renal tubulopathies. Here, we show that ablation of HNF-1β in mIMCD3 renal epithelial cells results in activation of β-catenin and increased expression of lymphoid enhancer-binding factor 1 (LEF1), a downstream effector in the canonical Wnt signaling pathway. Increased expression and nuclear localization of LEF1 are also observed in cystic kidneys from Hnf1b mutant mice. Expression of dominant-negative mutant HNF-1β in mIMCD3 cells produces hyperresponsiveness to exogenous Wnt ligands, which is inhibited by siRNA-mediated knockdown of Lef1. WT HNF-1β binds to two evolutionarily conserved sites located 94 and 30 kb from the mouse Lef1 promoter. Ablation of HNF-1β decreases H3K27 trimethylation repressive marks and increases β-catenin occupancy at a site 4 kb upstream to Lef1. Mechanistically, WT HNF-1β recruits the polycomb-repressive complex 2 that catalyzes H3K27 trimethylation. Deletion of the β-catenin-binding domain of LEF1 in HNF-1β-deficient cells abolishes the increase in Lef1 transcription and decreases the expression of downstream Wnt target genes. The canonical Wnt target gene, Axin2, is also a direct transcriptional target of HNF-1β through binding to negative regulatory elements in the gene promoter. These findings demonstrate that HNF-1β regulates canonical Wnt target genes through long-range effects on histone methylation at Wnt enhancers and reveal a new mode of active transcriptional repression by HNF-1β.

The Mechanism of Long Non-Coding RNA Plasmacytoma Variant Translocation 1 Regulating Hepatoma Cells Proliferation and Apoptosis—Targeting the Transcription Factor Lymphoid Enhancer-Binding Factor 1 to Promote the Expression of Downstream Baculoviral IAP Repeat Containing 5

Long non-coding RNA (lncRNA) PVT1 has been reported to be involved in the development of hepatocellular carcinoma (HCC). The expression of anti-apoptosis protein baculoviral IAP repeat containing 5 (BIRC5) is also increased in hepatoma cells and can be activated by lymphoid enhancer binding factor 1 (LEF1), which is one of the potential markers for HCC. The objective of this study is to explore the relationship between PVT1, BIRC5, and LEF1, so as to uncover the pathways and mechanisms of PVT1 promoting HCC. BIRC5 and PVT1 expression in normal liver cells and hepatoma cells was analyzed by RT-qPCR and western blotting. PVT1 short hairpin (sh)-RNA plasmids were transfected into PLC/PRF5 hepatoma cells to knockdown PVT1 expression, and then cell proliferation, colony formation, apoptosis and expression of related proteins were assessed. Besides, the interaction between PVT1 and miR-409-5p together with LEF1 and miR-409-5p was detected by dual luciferase assay. Results showed that the expression of BIRC5 and PVT1 were significantly increased in hepatoma cells and was highest in PLC/PRF5 compared with other hepatoma cells. Knockdown of PVT1 obviously reduced the ability of PLC/PRF5 cell proliferation and colony formation, whereas enhanced cell apoptosis. The protein expression of BIRC5 and LEF1 was also decreased after PVT1 was knockdown. Moreover, miR-409-5p level was increased after PVT1 silencing and it can interact with both PVT1 and LEF1. In conclusion, lncRNA PVT1 may exert its accelerative effect on HCC by targeting LEF1 in Hippo signaling pathway through miR-409-5p, thereby enhancing the expression of apoptosis inhibitor BIRC5.

Expression of lymphoid enhancer-binding factor 1 in breast fibroepithelial lesions

Phyllodes tumors (PTs) are rare epithelial-mesenchymal tumors of the breast with malignant potential. Here, we evaluate the nuclear expression of lymphoid enhancer-binding factor 1 (LEF-1), a transcription factor downstream of Wnt/β-catenin signaling, in fibroepithelial lesions of the breast. Excised fibroepithelial lesions of the breast were retrospectively reviewed, blinded to the original diagnosis, and classified according to World Health Organization (WHO) criteria. A tissue microarray (TMA) was composed with two representative cores from each case, including 24 benign lesions, 11 borderline phyllodes, and 8 malignant PTs. β-Catenin, LEF-1, p120, and E-cadherin immunohistochemistrywas performed on the TMA, and staining was quantified. The malignant/borderline PTs showed higher stromal LEF-1 expression than benign tumors (P<0.001). Stromal cells expressed LEF-1 in 100% (16/16 of core TMA) of malignant phyllodes, compared with 73% (16/22) borderline and 27% (13/48) benign tumors. The average LEF-1 H-score was 24.9, 6.1, and 1.5 for malignant, borderline, and benign tumors, respectively. Nuclear expression of β-catenin in the stromal component was more often seen in malignant than in borderline and benign tumors (44% versus 32% and 23%, respectively). Nine TMA cores of malignant tumors without nuclear β-catenin staining demonstrated LEF-1 expression. Both LEF-1 and nuclear β-catenin showed expression in the majority of borderline/malignant PTs suggesting a biological progression of Wnt/β-catenin pathway activation in the stromal component from benign to malignant tumors. Inhibitors for the Wnt/β-catenin pathway may provide alternative treatment options in the future for malignant or metastatic PTs.

High expression of LEF1 correlates with poor prognosis in solid tumors, but not blood tumors: a meta-analysis.

Background: Previously published studies have indicated that lymphoid enhancer-binding factor 1 (LEF1) expression could be recognized as a valuable biomarker to evaluate clinical outcome for various types of malignant cancer, but the results remained controversial. Therefore, we conducted this meta-analysis to pool the published estimates and discuss the relationship of LEF1 expression with cancer prognosis. Methods: Five electronic databases Pubmed, Web of Science, Embase, CNKI, and Wanfang were systematically searched for eligible literatures. Hazard ratios (HRs) and 95% confidence intervals (CIs) from the included studies were combined to estimate the effect of LEF1 expression on cancer patients’ survival. Results: Eleven original studies met the criteria and were enrolled for analysis. The results indicated that compared with patients in low LEF1 expression group, patients in high LEF1 expression group tended to have shorter overall survival (HR = 1.74, 95% CI: 1.06–2.86, P=0.029), especially for patients with solid tumors (HR = 2.39, 95% CI: 1.86–3.08, P=0.000). Conclusions: Individual evidence about the prognostic value of LEF1 expression in human cancers was limited. Our meta-analysis supported the suggestion that elevated LEF1 expression could function as a promising biomarker to predict the clinical outcomes for malignant cancers, especially solid tumors. More high-quality clinical studies are warranted to highlight the prognostic value of LEF1 expression in human cancers.

CLL-016: WNT3 and LEF1 Expression Levels and Outcome of Chronic Lymphocytic Leukemia in Egyptian Patients

Context Chronic lymphocytic leukemia (CLL), a hematologic malignancy, characterized by progressive accumulation of mature B lymphocytes. The role of Wnt signaling pathway has been reported in CLL biogenesis. Lymphoid enhancer-binding factor-1 (LEF1), a mediator of this canonical pathway has been identified in CLL. Objective To analyze Wnt signaling pathway members (WNT3) and its key mediator LEF1 expression levels in CLL patients and to assess their potential role as markers of CLL outcome. Design An observational prospective study from February 2017 till February 2018. Setting It was carried out in the Hematology unit at Oncology Center Mansoura University (OCMU). Patients This study was carried out on 35 newly diagnosed CLL patients in comparison with 15 adult controls, they were M/F 14/16 (47/53%), median age 63. Interventions The patients were subjected to history taking, physical examination and laboratory investigations of CLL. Wnt3 gene and LEF1 expression levels in peripheral blood of untreated CLL mononuclear cells and normal healthy controls were determined by RT-PCR. Main outcome measures Our study demonstrated significant upregulation of both Wnt3 and LEF1 in CLL PBMNC in comparison to healthy controls (P Results WNT3 and LEF1 were significantly decreased in CLL patients with ECOG 2&3 P=0.023 and 0.007, respectively. Untreated CLL patients harboring 17p deletion expressed significantly low LEF1 (P=0.033). A significant positive association was observed between WNT3 and LEF1 levels (Spearman r=0.74, P Conclusions WNT3 and its key mediator LEF1 were shown to be overexpressed and activated in CLL cells in comparison to healthy persons. Raising the interest that antagonizing Wnt signaling in CLL may represent an effective treatment potential. Interestingly, low expression of both WNT3 and LEF1 were associated with shortened survival in CLL patients which trigger more studies on a larger patient cohort.

Diagnostic Utility of LEF1 Immunohistochemistry in Differentiating Deep Penetrating Nevi From Histologic Mimics.

Deep penetrating nevi (DPNs) are intermediate grade lesions which have the capacity to recur, metastasize, or progress to melanoma. Differentiating DPN from other melanocytic lesions including blue and cellular blue nevi can be diagnostically challenging, and markers to distinguish these entities can be useful. Mutations of the β-catenin and mitogen-activated protein kinase pathways have recently been elucidated as distinctive of DPN. This pathway can subsequently activate lymphoid enhancer-binding factor 1 (LEF1), a transcription factor shown to facilitate the epithelial-mesenchymal transition to propagate tumorigenesis. Seventy-two cases in total were examined on hematoxylin and eosin sections and with β-catenin and LEF1 immunohistochemistry. This included: DPN (14), cellular blue nevi (19), blue nevi (15), congenital melanocytic nevi (12), and melanoma (12). Nuclear expression of LEF1, present throughout the entire depth of the lesion, was noted in 13/14 (93%) of DPN, 0/19 (0%) of cellular blue nevi, 0/15 (0%) of blue nevi, 1/12 (8%) of congenital melanocytic nevi, and 9/12 (75%) of melanoma cases. Nuclear expression of β-catenin, present throughout the entire depth of the lesion, was noted in 14/14 (100%) of DPN, 0/18 (0%) of cellular blue nevi, 0/15 (0%) of blue nevi, 1/12 (8%) of congenital melanocytic nevi, and 1/12 (8%) of melanoma cases. A majority of congenital melanocytic nevi demonstrated a gradient of LEF1 and β-catenin expression with more intense staining superficially and loss of staining with increasing depth. Deep, uniform nuclear LEF1 combined with β-catenin immunohistochemical staining can be useful in distinguishing DPN from histologic mimics.

MicroRNA-381 inhibits metastasis and epithelial-mesenchymal transition of glioblastoma cells through targeting LEF1.

Glioblastoma is a common intracranial malignancy that is extremely harmful to human life and health. Various microRNAs (miRNAs) have been reported to be involved in the progression of glioblastoma, except miR-381. Therefore, the purpose of this study is to investigate the role of miR-381 in glioblastoma. The expression of miR-381 and LEF1 (lymphoid enhancer-binding factor-1) was quantified using quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot analysis. Transwell and Dual-Luciferase reporter assays were used to investigate the regulatory mechanism of miR-381/LEF1 in glioblastoma. Downregulation of miR-381 was observed in A172 cells. In addition, the overexpression of miR-381 restrained migration and invasion of glioblastoma cells. Furthermore, overexpression of miR-381 inhibited epithelial-mesenchymal transition (EMT) in A172 cells. Further, miR-381 was confirmed to directly target LEF1 and negatively regulates its expression in glioblastoma cells. Downregulation of LEF1 also inhibited cell migration, invasion, and EMT in glioblastoma cells. More importantly, the upregulation of LEF1 abolished the inhibitory effect of miR-381 in glioblastoma cells. MiR-381 inhibits cell metastasis and EMT in glioblastoma by suppressing LEF1 expression.