Global gene expression changes following ELF3 knockdown in prostate epithelial cell lines
ABSTRACT: This study aimed to elucidate the role of ELF3, an epithelia-specific member of the ETS family, in normal prostate development and prostate cancer. Four comparisons (untreated, mock-transfected, scrambled siRNA, and targeted siRNA) were performed in two prostate epithelial cell lines BPH-1 (benign) and PC3 (malignant). Global gene expression arrays were performed for each combination.
Project description:This study aimed to elucidate the role of ELF3, an epithelia-specific member of the ETS family, in normal prostate development and prostate cancer. Four comparisons (untreated, mock-transfected, scrambled siRNA, and targeted siRNA) were performed in two prostate epithelial cell lines BPH-1 (benign) and PC3 (malignant). Global gene expression arrays were performed for each combination.
Project description:This study aimed to elucidate the role of ELF3, an ETS family member in normal prostate growth and prostate cancer. Silencing ELF3 in both benign prostate (BPH-1) and prostate cancer (PC3) cell lines resulted in decreased colony-forming ability, inhibition of cell migration and reduced cell viability due to cell cycle arrest, establishing ELF3 as a cell cycle regulator. Increased ELF3 expression in more advanced prostate tumours was shown by immunostaining of tissue microarrays and from analysis of gene expression and genetic alteration studies. This study indicates that ELF3 functions not only as a part of normal prostate epithelial growth but also as a potential oncogene in advanced prostate cancers.
Project description:The androgen receptor (AR) has a critical role in the development and progression of prostate cancer (PC) and is a major therapeutic target in this disease. The transcriptional activity of AR is modulated by the coregulators with which it interacts, and consequently deregulation of cofactor expression and/or activity impacts the expression of genes whose products can have a role in PC pathogenesis. Here we report that E74-like factor 3 (ELF3), a member of the ETS family of transcription factors, is a repressor of AR transcriptional activity. Exogenous expression of ELF3 represses AR transcriptional activity when assessed using reporter-based transfection assays or when evaluated on endogenous AR target genes. Conversely, ELF3 knock down increases the AR transcriptional activity. Biochemical dissection of this activity indicates that it results from the physical interaction between ELF3 and AR and that this interaction inhibits the recruitment of AR to specific androgen response elements within target gene promoters. Significantly, we observed that depletion of ELF3 expression in LNCaP cells promotes cell migration, whereas increased ELF3 expression severely inhibits tumor growth in vitro and in a mouse xenograft model. Taken together, these results suggest that modulation of ELF3 expression and/or AR/ELF3 interaction may have utility in the treatment of PC.
Project description:The Ets family of transcription factors is composed of more than 30 members. One of its members, Elf3, is expressed in virtually all epithelial cells as well as in many tumors, including breast tumors. Several studies observed that the promoter of the type II TGF-beta receptor gene (TbetaR-II) is strongly stimulated by Elf3 via two adjacent Elf3 binding sites, the A-site and the B-site. Here, we report the 2.2 A resolution crystal structure of a mouse Elf3 C-terminal fragment, containing the DNA-binding Ets domain, in complex with the B-site of mouse type II TGF-beta receptor promoter DNA (mTbetaR-II(DNA)). Elf3 contacts the core GGAA motif of the B-site from a major groove similar to that of known Ets proteins. However, unlike other Ets proteins, Elf3 also contacts sequences of the A-site from the minor groove of the DNA. DNA binding experiments and cell-based transcription studies indicate that minor groove interaction by Arg349 located in the Ets domain is important for Elf3 function. Equally interesting, previous studies have shown that the C-terminal region of Elf3, which flanks the Ets domain, is required for Elf3 binding to DNA. In this study, we determined that Elf3 amino acid residues within this flanking region, including Trp361, are important for the structural integrity of the protein as well as for the Efl3 DNA binding and transactivation activity.
Project description:Aquaporin-2 (AQP2) is a molecular water channel protein responsible for water reabsorption by the kidney collecting ducts. Many water balance disorders are associated with defects in AQP2 gene expression regulated by the peptide hormone vasopressin. Here, we studied roles of Elf3 (E26 transformation-specific (Ets)-related transcription factor 3) in AQP2 gene expression in the collecting duct cells (mpkCCD). Vasopressin increased AQP2 mRNA and protein levels without affecting AQP2 mRNA degradation, indicative of transcriptional regulation. Elf3 knockdown and overexpression, respectively, reduced and increased AQP2 gene expression under basal and vasopressin-stimulated conditions. However, the vasopressin-to-basal ratios of AQP2 gene expression levels remained constant, indicating that Elf3 does not directly mediate vasopressin response but modulates the level of AQP2 gene expression inducible by vasopressin. The Elf3-modulated AQP2 gene expression was associated with AQP2 promoter activity, in line with Elf3's ability to bind an Ets element in the AQP2 promoter. Mutation in the Ets element reduced both basal and vasopressin-stimulated AQP2 promoter activity, again without affecting vasopressin-to-basal ratios of the AQP2 promoter activity. Lithium chloride reduced both Elf3 and AQP2 mRNA in the mpkCCD cells as well as in mouse kidney inner medulla. We conclude that Elf3 modulates AQP2 promoter activity thereby gauging vasopressin-inducible AQP2 gene expression levels. Our data provide a potential explanation to lithium-induced nephrogenic diabetes insipidus where lithium reduces Elf3 and hence AQP2 abundance.
Project description:PBRM1 was found to be mutated in a high percentage of clear cell RCCs. We performed knockdown of PBRM1 via siRNA and compared with scrambled control in three different RCC cell lines. PBRM1 siRNA and mock treated cell lines were normalized together with 'hypoxic' clear cell renal tumors and normal renal tissue samples from GSE17818.
Project description:Microtubule affinity regulating kinase 4 (MARK4) plays a crucial role in the regulation of NOD-like receptor pyrin domain 3 (NLRP3) inflammasome activation, which leads to the generation of bioactive interleukin (IL)-1? and IL-18. E74-like ETS transcription factor 3 (ELF3) participates in endothelial inflammatory processes. We hypothesized that ELF3 modulates MARK4 expression in vascular endothelial cells, thus contributing to high glucose-mediated NLRP3 inflammasome activation. Plasma IL-1?, IL-18, NLRP3 inflammasome and MARK4 expression was increased in diabetic patients and rats. An in vitro study indicated that high glucose increased IL-1? and IL-18 expression and activated the NLRP3 inflammasome via upregulation of MARK4 in human umbilical vein endothelial cells (HUVECs). Furthermore, high glucose increased ELF3 expression. ELF3 downregulation reversed the effects of high glucose treatment. Accordingly, the effects of ELF3 overexpression were similar to those of high glucose treatment and were counteracted by siMARK4. Furthermore, ELF3 was found to interact with SET8. High glucose inhibited SET8 expression and histone H4 lysine 20 methylation (H4K20me1), a downstream target of SET8. Overexpression of SET8 inhibited high glucose-induced MARK4 expression and NLRP3 inflammasome activation. The effects of shSET8 were similar to those of high glucose treatment and were counteracted by siMARK4. A mechanistic study found that ELF3 and H4K20me1 were enriched in the MARK4 promoter region. si-ELF3 attenuated MARK4 promoter activity and augmented the inhibitory effect of SET8 on MARK4 promoter activity. Furthermore, SET8 downregulation and ELF3 upregulation were confirmed in diabetic patients and rats. In conclusion, ELF3 interacted with SET8 to modulate MARK4 expression, which participated in hyperglycaemia-mediated endothelial NLRP3 inflammasome activation.
Project description:Chromosomal abnormalities that give rise to elevated expression levels of the ETS genes ETV1, ETV4, ETV5, or ERG are prevalent in prostate cancer, but the function of these transcription factors in carcinogenesis is not clear. Previous work implicates ERG, ETV1, and ETV5 as regulators of invasive growth but not transformation in cell lines. Here we show that the PC3 prostate cancer cell line provides a model system to study the over-expression of ETV4. Anchorage independent growth assays and microarray analysis indicate that high ETV4 expression is critical for the transformation phenotype of PC3 cells. However, genes up-regulated upon ETV4 over-expression were very similar to genes up-regulated by ETV1 over-expression in the RWPE-1 normal prostate cell line. Together these data indicate that the ETV4 dependent transformation phenotype observed in PC3 cells is due to the genetic background of the cell line, rather than a distinct characteristic of ETV4. Furthermore, these findings suggest that the function of ETS genes in prostate cancer may differ based on other genetic alterations in a tumor. Two sets of two color experiments. First is PC3 cells expressing one of two independent ETV4 shRNAs versus PC3 cells expressing a control shRNA (luciferase). Second is RWPE-1 cells expressing 3xFlag tagged ETV4 versus RWPE-1 cells with a control (empty) vector.
Project description:Purpose:The present study aims to investigate the role of ELF3-AS1 in oral squamous cell carcinoma (OSCC). Patients and methods:A total of 112 patients with OSCC were admitted in Guangdong Provincial Stomatological Hospital from March 2016 to March 2019. RT-qPCR, cells and transient transfections, cell proliferation rate measurements and Western blots were carried out to analyze the samples. Results:In the present study, we showed that ELF3-AS1 and glucose transporter 1 (GLUT1) were both upregulated in OSCC tissues, and those two factors were positively correlated. In OSCC cells, ELF3-AS1 overexpression resulted in upregulation, while ELF3-AS1 siRNA silencing caused downregulated expression of GLUT1 and glucose uptake. ELF3-AS1 and GLUT1 overexpression resulted in increased rate of OSCC cells, while ELF3-AS1 and GLUT1 siRNA silencing resulted in decreased proliferation rate of OSCC cells. In addition, GLUT1 siRNA silencing attenuated the effects of ELF3-AS1 overexpression. Conclusion:Therefore, ELF3-AS1 promotes the proliferation of OSCC cells by reprogramming glucose metabolism.
Project description:Hepatocellular carcinoma (HCC) is one of the most common malignant cancers and currently the third leading cause of cancer-related deaths, worldwide. Epithelial-mesenchymal transition (EMT) plays a major role in HCC progression. In this study, we first found that the expression of E74-like ETS transcription factor 3 (ELF3), a member of the E-twenty-six family of transcription factors, was increased in HCC tissues, and that ELF3 overexpression was associated with poor prognoses for HCC patients. Gain-of-function and loss-of-function studies revealed that increased ELF3 expression promoted HCC cell proliferation, migration, and invasion, while these processes were inhibited when ELF3 was silenced. Additionally, ELF3 was found to promote EMT, which we demonstrated through decreased E-cadherin expression and increased N-cadherin and fibronectin expression. ELF3 knockdown reversed EMT via repressing ZEB1 expression through miR-141-3p upregulation. Chromatin immunoprecipitation assays revealed that ELF3 bound to the miR-141-3p promoter, suppressing miR-141-3p expression. Taken together, our data show that ELF3 repressed E-cadherin and promoted EMT in HCC cells by suppressing miR-141-3p, thereby activating ZEB1. Thus, ELF3 may be a potential prognostic biomarker and/or therapeutic target for HCC.