hes1-protein--human and Prostatic-Neoplasms

Prostate cancer is the second leading cause of cancer death among men in the United States. The androgen receptor (AR) antagonist enzalutamide is a Food and Drug Administration-approved drug for treatment of patients with late-stage prostate cancer and is currently under clinical study for early-stage prostate cancer treatment. After a short positive response period, tumors will develop drug resistance. In this study using RNA-Seq and bioinformatics analyses, we observed that NOTCH signaling is a deregulated pathway in enzalutamide-resistant cells.

Topics: Animals; Benzamides; Cell Line, Tumor; Drug Resistance, Neoplasm; Humans; Male; Mice; Mice, Nude; Nitriles; Phenylthiohydantoin; Prostatic Neoplasms; Proto-Oncogene Proteins c-myc; Receptor, Notch1; Receptor, Notch2; Signal Transduction; Tetrahydronaphthalenes; Transcription Factor HES-1; Valine; Xenograft Model Antitumor Assays

Prostate Cancer (PCa) holds the second place in terms of cancer-related mortality rate among men. The Notch signalling pathway regulates the proliferation and differentiation in embryonic and adult tissues and determines the cell fate. The body of knowledge in the present literature is currently controversial about the effect of the Notch pathway on prostatic cancer. Therefore, the present study aimed to examine the immunolocalization and expression levels of Notch1-4, Jagged1-2, Delta, HES1 and HES5 from among the members of the Notch signalling pathway in tissues of normal, prostatic intraepithelial neoplasia (PIN) and malignant prostate. The current study included a sample of 20 patients with localised prostatic adenocarcinoma, 18 patients with high grade PIN (H-PIN) and 18 normal prostatic tissue. Immunolocalisations of Notch1, 2, 3, 4, Jagged1, 2, Delta, HES1 and HES5 were identified through the immunohistochemical method. The findings of the present study showed that all in-scope members of the Notch signalling pathway were localised in PIN structures to a greater extent than in other tissues and from amongst these members, specifically Notch1, Notch4, Jagged1 and HES1 were at more significant levels. Consequently, the findings of the present study may indicate that the Notch signalling pathway can play a role especially in the formation of PIN structures.

Topics: Adenocarcinoma; Adult; Basic Helix-Loop-Helix Transcription Factors; Biomarkers, Tumor; Calcium-Binding Proteins; Case-Control Studies; Follow-Up Studies; Homeodomain Proteins; Humans; Immunoenzyme Techniques; Intercellular Signaling Peptides and Proteins; Jagged-1 Protein; Male; Membrane Proteins; Middle Aged; Neoplasm Grading; Neoplasm Staging; Prognosis; Prostate; Prostatic Intraepithelial Neoplasia; Prostatic Neoplasms; Receptors, Notch; Serrate-Jagged Proteins; Signal Transduction; Transcription Factor HES-1

Phospholipase Cε (PLCε), a key regulator of diverse cellular functions, has been implicated in various malignancies. Indeed, PLCε functions include cell proliferation, apoptosis and malignant transformation. Here, we show that PLCε expression is elevated in prostate cancer (PCa) tissues compared to benign prostate tissues. Furthermore, PLCε depletion using an adenovirally delivered shRNA significantly decreased cell growth and colony formation, arresting the PC3 and LNCaP cell lines in the S phase of the cell cycle. We also observed that PLCε was significantly correlated with Notch1 and androgen receptor (AR). Additionally, we demonstrate that the activation of both the Notch and AR signalling pathways is involved in PLCε-mediated oncogenic effects in PCa. Our findings suggest that PLCε is a putative oncogene and prognostic marker, potentially representing a novel therapeutic target for PCa.

Topics: Active Transport, Cell Nucleus; Basic Helix-Loop-Helix Transcription Factors; Cell Cycle Checkpoints; Cell Growth Processes; Cell Line, Tumor; Cell Nucleus; Gene Knockdown Techniques; Homeodomain Proteins; Humans; Male; Middle Aged; Phosphoinositide Phospholipase C; Prostatic Neoplasms; Prostatic Neoplasms, Castration-Resistant; Receptor, Notch1; Receptors, Androgen; RNA, Messenger; S Phase; Signal Transduction; Transcription Factor HES-1

PTOV1 is an adaptor protein with functions in diverse processes, including gene transcription and protein translation, whose overexpression is associated with a higher proliferation index and tumor grade in prostate cancer (PC) and other neoplasms. Here we report its interaction with the Notch pathway and its involvement in PC progression.. Stable PTOV1 knockdown or overexpression were performed by lentiviral transduction. Protein interactions were analyzed by co-immunoprecipitation, pull-down and/or immunofluorescence. Endogenous gene expression was analyzed by real time RT-PCR and/or Western blotting. Exogenous promoter activities were studied by luciferase assays. Gene promoter interactions were analyzed by chromatin immunoprecipitation assays (ChIP). In vivo studies were performed in the Drosophila melanogaster wing, the SCID-Beige mouse model, and human prostate cancer tissues and metastasis. The Excel package was used for statistical analysis.. Knockdown of PTOV1 in prostate epithelial cells and HaCaT skin keratinocytes caused the upregulation, and overexpression of PTOV1 the downregulation, of the Notch target genes HEY1 and HES1, suggesting that PTOV1 counteracts Notch signaling. Under conditions of inactive Notch signaling, endogenous PTOV1 associated with the HEY1 and HES1 promoters, together with components of the Notch repressor complex. Conversely, expression of active Notch1 provoked the dismissal of PTOV1 from these promoters. The antagonist role of PTOV1 on Notch activity was corroborated in the Drosophila melanogaster wing, where human PTOV1 exacerbated Notch deletion mutant phenotypes and suppressed the effects of constitutively active Notch. PTOV1 was required for optimal in vitro invasiveness and anchorage-independent growth of PC-3 cells, activities counteracted by Notch, and for their efficient growth and metastatic spread in vivo. In prostate tumors, the overexpression of PTOV1 was associated with decreased expression of HEY1 and HES1, and this correlation was significant in metastatic lesions.. High levels of the adaptor protein PTOV1 counteract the transcriptional activity of Notch. Our evidences link the pro-oncogenic and pro-metastatic effects of PTOV1 in prostate cancer to its inhibitory activity on Notch signaling and are supportive of a tumor suppressor role of Notch in prostate cancer progression.

Topics: Animals; Basic Helix-Loop-Helix Transcription Factors; Biomarkers, Tumor; Cell Cycle Proteins; Cell Line, Tumor; Cell Proliferation; Drosophila melanogaster; Gene Expression Regulation, Neoplastic; Gene Knockdown Techniques; Homeodomain Proteins; Humans; Male; Mice; Neoplasm Metastasis; Neoplasm Proteins; Prostatic Neoplasms; Receptors, Notch; Signal Transduction; Transcription Factor HES-1; Transcriptional Activation

Prostate carcinoma is among the most common causes of cancer-related death in men, representing 15% of all male malignancies in developed countries. Neuroendocrine differentiation (NED) has been associated with tumor progression, poor prognosis, and with the androgen-independent status. Currently, no successful therapy exists for advanced, castration-resistant disease. Because hypoxia has been linked to prostate cancer progression and unfavorable outcome, we sought to determine whether hypoxia would impact the degree of neuroendocrine differentiation of prostate cancer cells in vitro.. Exposure of LNCaP cells to low oxygen tension induced a neuroendocrine phenotype, associated with an increased expression of the transcription factor neurogenin3 and neuroendocrine markers, such as neuron-specific enolase, chromogranin A, and β3-tubulin. Moreover, hypoxia triggered a significant decrease of Notch 1 and Notch 2 mRNA and protein expression, with subsequent downregulation of Notch-mediated signaling, as shown by reduced levels of the Notch target genes, Hes1 and Hey1. NED was promoted by attenuation of Hes1 transcription, as cells expressing a dominant-negative form of Hes1 displayed increased levels of neuroendocrine markers under normoxic conditions. Although hypoxia downregulated Notch 1 and Notch 2 mRNA transcription and receptor activation also in the androgen-independent cell lines, PC-3 and Du145, it did not change the extent of NED in these cultures, suggesting that androgen sensitivity may be required for transdifferentiation to occur.. Hypoxia induces NED of LNCaP cells in vitro, which seems to be driven by the inhibition of Notch signaling with subsequent downregulation of Hes1 transcription.

Topics: Androgens; Basic Helix-Loop-Helix Transcription Factors; Cell Cycle Proteins; Cell Differentiation; Cell Line, Tumor; Cell Transformation, Neoplastic; Gene Expression Regulation, Neoplastic; Homeodomain Proteins; Humans; Hypoxia; Male; Nerve Tissue Proteins; Neuroendocrine Tumors; Oxygen; Prostatic Neoplasms; Receptor, Notch1; Receptor, Notch2; Transcription Factor HES-1

Neuronal synaptic junction protein δ-catenin (CTNND2) is often overexpressed in prostatic adenocarcinomas but the mechanisms of its activation are unknown. To address this question, we studied the hypothesis that Hes1, human homolog of Drosophila Hairy and enhancer of split (Hes) 1, is a transcriptional repressor of δ-catenin expression and plays an important role in molecular carcinogenesis.. We identified that, using a δ-catenin promoter reporter assay, Hes1, but not its inactive mutant, significantly repressed the upregulation of δ-catenin-luciferase activities induced by E2F1. Hes1 binds directly to the E-boxes on δ-catenin promoter and can reduce the expression of δ-catenin in prostate cancer cells. In prostate cancer CWR22-Rv1 and PC3 cell lines, which showed distinct δ-catenin overexpression, E2F1 and Hes1 expression pattern was altered. The suppression of Hes1 expression, either by γ-secretase inhibitors or by siRNA against Hes1, increased δ-catenin expression. γ-Secretase inhibition delayed S/G2-phase transition during cell cycle progression and induced cell shape changes to extend cellular processes in prostate cancer cells. In neuroendocrine prostate cancer mouse model derived allograft NE-10 tumors, δ-catenin showed an increased expression while Hes1 expression was diminished. Furthermore, E2F1 transcription was very high in subgroup of NE-10 tumors in which Hes1 still displayed residual expression, while its expression was only moderately increased in NE-10 tumors where Hes1 expression was completely suppressed.. These studies support coordinated regulation of δ-catenin expression by both the activating transcription factor E2F1 and repressive transcription factor Hes1 in prostate cancer progression.

Topics: Animals; Basic Helix-Loop-Helix Transcription Factors; Blotting, Western; Catenins; Cell Line, Tumor; Delta Catenin; Dipeptides; E2F1 Transcription Factor; Electrophoretic Mobility Shift Assay; Flow Cytometry; Homeodomain Proteins; Humans; Immunohistochemistry; Immunoprecipitation; In Vitro Techniques; Male; Mice; Microscopy, Fluorescence; Prostatic Neoplasms; Reverse Transcriptase Polymerase Chain Reaction; Transcription Factor HES-1

This study tested the possible functional relationship of two signalling mechanisms shown previously to be involved in human prostate cancer (PCa), Notch and voltage-gated sodium channel. Notch1 and Notch2 were differentially expressed in PCa cell lines of varying metastatic potential (LNCaP, PC-3, PC-3M) in comparison to a normal prostate cell line (PNT2), whereas Notch3 and Notch4 were not expressed. The Notch ligand Jagged1, but not Jagged2, was increased in all cell lines, whereas the Notch downstream target Deltex was not expressed. In comparison to the LNCaP cell line, Hes1, another downstream target, showed elevated expression in the metastatic PC-3 and PC-3M cells and promoted lateral motility. In contrast, the Notch ligand Delta-like1 (Dll1) levels were higher in LNCaP compared with PC-3 and PC-3M cells. Importantly, decreasing Dll1 expression increased the lateral motility of PC-3 cells, whereas blocking voltage-gated Na(+) channel activity with tetrodotoxin decreased motility. However, the effect of Dll1 was independent of Notch signalling through Hes1 and voltage-gated Na(+) channel expression/activity.

Topics: Amyloid Precursor Protein Secretases; Basic Helix-Loop-Helix Transcription Factors; Calcium-Binding Proteins; Cell Line, Tumor; Cell Movement; Cell Proliferation; Dimethyl Sulfoxide; Enzyme Inhibitors; Epithelial Cells; Homeodomain Proteins; Humans; Intercellular Signaling Peptides and Proteins; Ion Channel Gating; Jagged-1 Protein; Male; Membrane Proteins; Poisons; Prostatic Neoplasms; Proto-Oncogene Proteins; Receptor, Notch1; Receptor, Notch2; Receptor, Notch3; Receptor, Notch4; Receptors, Notch; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Serrate-Jagged Proteins; Signal Transduction; Sodium Channels; Solvents; Tetrodotoxin; Transcription Factor HES-1; Tumor Cells, Cultured

Prostate cancer bone metastases are characterized by their ability to induce osteoblastic lesions and local bone formation. It has been suggested that bone metastatic prostate cancer cells are osteomimetic and capable of expressing genes and proteins typically expressed by osteoblasts. The ability of preosteoblasts to differentiate and express osteoblastic genes depends on several pathways, including Notch and MAPK. Here we show that notch1 expression is increased 4-5 times in C4-2B and MDA PCa 2b cells (osteoblastic skeletal prostate metastatic cancer cell lines) when compared with nonskeletal metastatic cell lines (LNCaP and DU145). Notch1 ligand, dll1, is expressed only in C4-2B cells. Immunohistochemical studies demonstrate that Notch1 is present in both human clinical samples from prostate cancer bone metastases and the C4-2B cell line. To determine whether prostate cancer bone metastases respond to osteogenic induction similar to osteoblasts, C4-2B cells were cultured in osteogenic medium that promotes mineralization. C4-2B cells mineralize and express HES-1 (a downstream target of Notch), an effect that is completely inhibited by L-685,458, a Notch activity inhibitor. Furthermore, osteogenic induction increases ERK activation, runx2 expression, and nuclear localization, independent of Notch signaling. Finally, we show that Notch and ERK activation are essential for Runx2 DNA binding activity and osteocalcin gene expression in C4-2B cells in response to osteogenic induction. These studies demonstrate that prostate cancer bone metastatic cell lines acquire osteoblastic properties through independent activation of ERK and Notch signaling; presumably, both pathways are activated in the bone microenvironment.

Topics: Basic Helix-Loop-Helix Transcription Factors; Blotting, Western; Bone Neoplasms; Calcium; Carbamates; Cell Differentiation; Cell Line, Tumor; Cell Nucleus; Core Binding Factor Alpha 1 Subunit; Dipeptides; DNA; Enzyme Activation; Homeodomain Proteins; Humans; Immunohistochemistry; Intracellular Signaling Peptides and Proteins; Male; Membrane Proteins; Mitogen-Activated Protein Kinases; Models, Biological; Neoplasm Metastasis; Neoplasm Proteins; Osteoblasts; Prostatic Neoplasms; Protein Binding; Receptors, Notch; Reverse Transcriptase Polymerase Chain Reaction; RNA; RNA, Ribosomal, 18S; Signal Transduction; Time Factors; Transcription Factor HES-1; Transcription Factors