Research IndicatorsGraph generated 16 March 2017 using data from PubMed using criteria.
Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic. Tag cloud generated 16 March, 2017 using data from PubMed, MeSH and CancerIndex
Specific Cancers (5)
Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.
Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).
OMIM, Johns Hopkin University
Referenced article focusing on the relationship between phenotype and genotype.
International Cancer Genome Consortium.
Summary of gene and mutations by cancer type from ICGC
Cancer Genome Anatomy Project, NCI
COSMIC, Sanger Institute
Somatic mutation information and related details
GEO Profiles, NCBI
Search the gene expression profiles from curated DataSets in the Gene Expression Omnibus (GEO) repository.
Latest Publications: MAML1 (cancer-related)
Corilagin is a natural plant polyphenol tannic acid with antitumor, anti-inflammatory, and anti-oxidative properties. However, the mechanisms of its actions are largely unknown. Our group reported that corilagin could induce cell inhibition in human breast cancer cell line MCF-7 and human liver hepatocellular carcinoma cell lines HepG2. We report here that corilagin inhibits cholangiocarcinoma (CCA) development through regulating Notch signaling pathway. We found that, in vitro, corilagin inhibited CCA cell proliferation, migration and invasion, promoted CCA cell apoptosis, and inhibited Notch1 and Notch signaling pathway protein expression. Co-immunoprecipitation was used to establish Notch intracellular domain (NICD) interaction with MAML1 and P300 in CCA. Importantly, corilagin reduced Hes1 mRNA level through inhibiting Hes1 promoter activity. In nude mice, corilagin inhibited CCA growth and repressed the expression of Notch1 and mTOR. These results indicate that corilagin may control CCA cell growth by downregulating the expression of Notch1. Therefore, our findings suggest that corilagin may have the potential to become a new therapeutic drug for human CCA.
Narayanappa R, Rout P, Aithal MG, Chand AKAberrant expression of Notch1, HES1, and DTX1 genes in glioblastoma formalin-fixed paraffin-embedded tissues.
Tumour Biol. 2016; 37(5):6935-42 [PubMed
] Related Publications
Glioblastoma is the most common malignant brain tumor accounting for more than 54 % of all gliomas. Despite aggressive treatments, median survival remains less than 1 year. This might be due to the unavailability of effective molecular diagnostic markers and targeted therapy. Thus, it is essential to discover molecular mechanisms underlying disease by identifying dysregulated pathways involved in tumorigenesis. Notch signaling is one such pathway which plays an important role in determining cell fates. Since it is found to play a critical role in many cancers, we investigated the role of Notch genes in glioblastoma with an aim to identify biomarkers that can improve diagnosis. Using real-time PCR, we assessed the expression of Notch genes including receptors (Notch1, Notch2, Notch3, and Notch4), ligands (JAG1, JAG2, and DLL3), downstream targets (HES1 and HEY2), regulator Deltex1 (DTX1), inhibitor NUMB along with transcriptional co-activator MAML1, and a component of gamma-secretase complex APH1A in 15 formalin-fixed paraffin-embedded (FFPE) patient samples. Relative quantification was done by the 2(-ΔΔCt) method; the data are presented as fold change in gene expression normalized to an internal control gene and relative to the calibrator. The data revealed aberrant expression of Notch genes in glioblastoma compared to normal brain. More than 85 % of samples showed high Notch1 (P = 0.0397) gene expression and low HES1 (P = 0.011) and DTX1 (P = 0.0001) gene expression. Our results clearly show aberrant expression of Notch genes in glioblastoma which can be used as putative biomarkers together with histopathological observation to improve diagnosis, therapeutic strategies, and patient prognosis.
Feng C, Xiong Z, Jiang H, et al.Genetic alteration in notch pathway is associated with better prognosis in renal cell carcinoma.
Biofactors. 2016 Jan-Feb; 42(1):41-8 [PubMed
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Notch signaling was associated with a variety of cancers but was not comprehensively studied in clear-cell renal cell carcinoma (ccRCC). We have in this study studied the genetic alteration (mutation and copy number variance) of Notch gene set in the Cancer Genome Atlas (TCGA) Kidney Renal Clear Cell Carcinoma (KIRC) database. We found that Notch pathway was frequently altered in ccRCC. The Notch gene set was genetically altered in 182 (44%) of the 415 ccRCC patients. CNV was the predominant type of alteration in most genes. Alterations in KAT2B and MAML1 occurred in 13% and 19% of patients, respectively, both of which were functionally active in ccRCC. Deletion of VHL was exclusively found in cases with Notch alteration. Overall survival was longer in ccRCC patients with altered-Notch pathway. The median survival was 90.41 months in Notch-altered cases and 69.15 in Notch-unaltered cases (P = 0.0404). The median disease free time was 89.82 months in Notch-altered cases and 77.27 months in in Notch-unaltered cases (P = 0.935). Conclusively, Notch signaling was altered in almost half of the ccRCC patients and copy number variances in MAML1 and KAT2B were predominant changes. These findings broadened our understanding of the role of Notch in ccRCC.
Moghbeli M, Forghanifard MM, Sadrizadeh A, et al.Role of Msi1 and MAML1 in Regulation of Notch Signaling Pathway in Patients with Esophageal Squamous Cell Carcinoma.
J Gastrointest Cancer. 2015; 46(4):365-9 [PubMed
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PURPOSE: Developmental pathways such as Wnt and Notch are involved in different cellular functions from the cell cycle regulation to self-renewal. Therefore, aberrations in these pathways may cause tumorigenesis. Msi1 has a critical regulatory role for the Wnt and Notch pathways. In the present study, we have assessed the probable correlation between the Msi1 and MAML1 in esophageal squamous cell carcinoma (ESCC) progression and metastasis.
METHODS: Levels of Msi1 and MAML1 mRNA expression in 51 ESCC patients were compared to the normal tissues using real-time polymerase chain reaction (PCR).
RESULTS: Nine out of 51 (17.6 %) cases had Msi1/MAML1 overexpression, and there was a significant correlation between such overexpressed cases and tumor location (p = 0.013).
CONCLUSIONS: We showed that there is not any direct correlation and feedback between the Msi1 and MAML1 in ESCC patients.
Activation of Notch signaling contributes to glioblastoma multiform (GBM) tumorigenesis. However, the molecular mechanism that promotes the Notch signaling augmentation during GBM genesis remains largely unknown. Identification of new factors that regulate Notch signaling is critical for tumor treatment. The expression levels of RND3 and its clinical implication were analyzed in GBM patients. Identification of RND3 as a novel factor in GBM genesis was demonstrated in vitro by cell experiments and in vivo by a GBM xenograft model. We found that RND3 expression was significantly decreased in human glioblastoma. The levels of RND3 expression were inversely correlated with Notch activity, tumor size, and tumor cell proliferation, and positively correlated with patient survival time. We demonstrated that RND3 functioned as an endogenous repressor of the Notch transcriptional complex. RND3 physically interacted with NICD, CSL, and MAML1, the Notch transcriptional complex factors, promoted NICD ubiquitination, and facilitated the degradation of these cofactor proteins. We further revealed that RND3 facilitated the binding of NICD to FBW7, a ubiquitin ligase, and consequently enhanced NICD protein degradation. Therefore, Notch transcriptional activity was inhibited. Forced expression of RND3 repressed Notch signaling, which led to the inhibition of glioblastoma cell proliferation in vitro and tumor growth in the xenograft mice in vivo. Downregulation of RND3, however, enhanced Notch signaling activity, and subsequently promoted glioma cell proliferation. Inhibition of Notch activity abolished RND3 deficiency-mediated GBM cell proliferation. We conclude that downregulation of RND3 is responsible for the enhancement of Notch activity that promotes glioblastoma genesis.
p53 and Notch-1 play important roles in breast cancer biology. Notch-1 inhibits p53 activity in cervical and breast cancer cells. Conversely, p53 inhibits Notch activity in T-cells but stimulates it in human keratinocytes. Notch co-activator MAML1 binds p53 and functions as a p53 co-activator. We studied the regulation of Notch signaling by p53 in MCF-7 cells and normal human mammary epithelial cells (HMEC). Results show that overexpression of p53 or activation of endogenous p53 with Nutlin-3 inhibits Notch-dependent transcriptional activity and Notch target expression in a dose-dependent manner. This effect could be partially rescued by transfection of MAML1 but not p300. Standard and quantitative co-immunoprecipitation experiments readily detected a complex containing p53 and Notch-1 in MCF-7 cells. Formation of this complex was inhibited by dominant negative MAML1 (DN-MAML1) and stimulated by wild-type MAML1. Standard and quantitative far-Western experiments showed a complex including p53, Notch-1, and MAML1. Chromatin immunoprecipitation (ChIP) experiments showed that p53 can associate with Notch-dependent HEY1 promoter and this association is inhibited by DN-MAML1 and stimulated by wild-type MAML1. Our data support a model in which p53 associates with the Notch transcriptional complex (NTC) in a MAML1-dependent fashion, most likely through a p53-MAML1 interaction. In our cellular models, the effect of this association is to inhibit Notch-dependent transcription. Our data suggest that p53-null breast cancers may lack this Notch-modulatory mechanism, and that therapeutic strategies that activate wild-type p53 can indirectly cause inhibition of Notch transcriptional activity.
Aberrant activation of Notch signaling has an essential role in colorectal cancer (CRC) progression. Amplified in breast cancer 1 (AIB1), also known as steroid receptor coactivator 3 or NCOA3, is a transcriptional coactivator that promotes cancer cell proliferation and invasiveness. However, AIB1 implication in CRC progression through enhancing Notch signaling is unknown. In this study, we found that several CRC cell lines expressed high levels of AIB1, and knockdown of AIB1 decreased cell proliferation, colony formation and tumorigenesis of these CRC cells. Specifically, knockdown of AIB1 inhibited cell cycle progression at G1 phase by decreasing the mRNA levels of cyclin A2, cyclin B1, cyclin E2 and hairy and enhancer of split (Hes) 1. Furthermore, AIB1 interacted with Notch intracellular domain and Mastermind-like 1 and was recruited to the Hes1 promoter to enhance Notch signaling. Downregulation of AIB1 also decreased CRC cell invasiveness in vitro and lung metastasis in vivo. Besides that, knockout of AIB1 in mice inhibited colon carcinogenesis induced by azoxymethane/dextran sodium sulfate treatment. The mRNA levels of cyclin B1 and Hes5 were downregulated, but p27, ATOH1 and MUC2 were upregulated in the colon tumors from AIB1-deficient mice compared with those from wild-type mice. Thus, our results signify the importance of AIB1 in CRC and demonstrate that AIB1 promotes CRC progression at least in part through enhancing Notch signaling, suggesting that AIB1 is a potential molecular target for CRC treatment.
Taleb S, Abbaszadegan MR, Moghbeli M, et al.HES1 as an independent prognostic marker in esophageal squamous cell carcinoma.
J Gastrointest Cancer. 2014; 45(4):466-71 [PubMed
] Related Publications
BACKGROUND: Notch signaling is one of the main involved pathways in cell differentiation and organogenesis, and its deregulation may lead to tumorigenesis. In this pathway, targeted to the CSL (CBF1, Suppressor of Hairless or Lag-1) complex, notch intracellular domain (NICD) releases corepressors and recruits MAML1 as coactivator triggering the activation of notch signaling transcription complex. Hairy enhance of split-1 (HES1) is one of the notch signaling target genes which is a basic helix-loop-helix (bHLH) transcription factor acting as a proliferation stimulator through the suppression of cell cycle inhibitors such as p27 and p21.
AIMS: In this study, we aimed to analyze the role of HES1 in the progression of esophageal squamous cell carcinoma (ESCC).
METHODS: Messenger RNA (mRNA) expression of HES1 in fresh tumoral tissues and their margin normal samples were assessed in 50 ESCC patients by real-time polymerase chain reaction (RT-PCR).
RESULTS: Thirteen out of 50 cases (26 %) had HES1 underexpression, while HES1 overexpression was observed only in 4 (8 %) samples. HES1 underexpression was significantly correlated with tumor depth of invasion (P = 0.035).
CONCLUSION: Although we have not observed any significant correlation between the HES1 expression and notch activation in ESCC, this study is the first report that elucidated the HES1 underexpression in ESCC and revealed its correlation with the invasiveness of ESCC.
Activation of the NOTCH receptors relies on their intracellular proteolysis by the gamma-secretase complex. This cleavage liberates the NOTCH intracellular domain (NIC) thereby allowing the translocation of NIC towards the nucleus to assemble into a transcriptional platform. Little information is available regarding the regulatory steps operating on NIC following its release from the transmembrane receptor up to its association with transcriptional partners. Interfering with these regulatory steps might potentially influences the nuclear outcome of NOTCH signalling. Herein, we exploited a reliable model to study the molecular events occurring subsequent to NOTCH1 cleavage. In pancreatic cancer cells, pulse of NOTCH1 activation led to increased expression of NOTCH target genes namely HES1 and c-MYC. We uncovered that, upon its release, the NOTCH1 intracellular domain, NIC1, undergoes a series of post-translational modifications that include phosphorylation. Most interestingly, we found that activation of the MEK/ERK pathway promotes HES1 expression. Inhibition of the gamma-secretase complex prevented the MEK/ERK-induced HES1 expression suggesting a NOTCH-dependent mechanism. Finally, higher levels of NIC1 were found associated with its transcriptional partners [CBF1, Su(H) and LAG-1] (CSL) and MASTERMIND-LIKE 1 (MAML1) upon MEK/ERK activation providing a potential mechanism whereby the MEK/ERK pathway promotes expression of NOTCH target genes. For the first time, our data exposed a signalling pathway, namely the MEK/ERK pathway that positively impacts on NOTCH nuclear outcome.
He Y, Meng XM, Huang C, et al.Long noncoding RNAs: Novel insights into hepatocelluar carcinoma.
Cancer Lett. 2014; 344(1):20-7 [PubMed
] Related Publications
Recent advances in non-protein coding part of human genome analysis have discovered extensive transcription of large RNA transcripts that lack of coding protein function, termed long noncoding RNAs (lncRNAs). It is becoming evident that lncRNAs may be an important class of pervasive genes involved in carcinogenesis and metastasis. However, the biological and molecular mechanisms of lncRNAs in diverse diseases are not yet fully understood. Thus, it is anticipated that more efforts should be made to clarify the lncRNAs world. Moreover, accumulating studies have demonstrated that a class of lncRNAs are dysregulated in hepatocellular carcinoma(HCC) and closely related with tumorigenesis, metastasis, prognosis or diagnosis. In this review, we will briefly discuss the regulation and functional role of lncRNAs in HCC, therefore evaluating the potential of lncRNAs as prospective novel therapeutic targets in HCC.
Genomic, transcriptional, and proteomic analyses of brain tumors reveal subtypes that differ in pathway activity, progression, and response to therapy. However, a number of small molecule inhibitors under development vary in strength of subset and pathway-specificity, with molecularly targeted experimental agents tending toward stronger specificity. The Notch signaling pathway is an evolutionarily conserved pathway that plays an important role in multiple cellular and developmental processes. We investigated the effects of Notch pathway inhibition in glioma tumor-initiating cell (GIC, hereafter GIC) populations using γ secretase inhibitors. Drug cytotoxicity testing of 16 GICs showed differential growth responses to the inhibitors, stratifying GICs into responders and nonresponders. Responder GICs had an enriched proneural gene signature in comparison to nonresponders. Also gene set enrichment analysis revealed 17 genes set representing active Notch signaling components NOTCH1, NOTCH3, HES1, MAML1, DLL-3, JAG2, and so on, enriched in responder group. Analysis of The Cancer Genome Atlas expression dataset identified a group (43.9%) of tumors with proneural signature showing high Notch pathway activation suggesting γ secretase inhibitors might be of potential value to treat that particular group of proneural glioblastoma (GBM). Inhibition of Notch pathway by γ secretase inhibitor treatment attenuated proliferation and self-renewal of responder GICs and induces both neuronal and astrocytic differentiation. In vivo evaluation demonstrated prolongation of median survival in an intracranial mouse model. Our results suggest that proneural GBM characterized by high Notch pathway activation may exhibit greater sensitivity to γ secretase inhibitor treatment, holding a promise to improve the efficiency of current glioma therapy.
Li FR, Li Q, Zhou HX, et al.Detection of circulating tumor cells in breast cancer with a refined immunomagnetic nanoparticle enriched assay and nested-RT-PCR.
Nanomedicine. 2013; 9(7):1106-13 [PubMed
] Related Publications
UNLABELLED: Early detection of circulation tumor cells (CTCs) in breast cancer patients has great clinical relevance. Currently, immunomagnetic microparticles enriched assays require Fe3O4 inner cores, making it difficult to improve sensitivity. In this study, we prepared magnetic nanoparticles with carbon-coated pure iron (Fe@C) acted as the core, Conjugating with EpCAM monoclonal antibody for immunomagnetic nanoparticles(IMPs). IMPs were used in conjunction with immunocytochemistry (ICC) to develop a refined immunomagnetic nanoparticles enriched assay (IMPEA) for detection of circulating tumor cells (CTCs) in breast cancer patients. Compared with nested RT-PCR, this method achieved the same sensitivity, but with a significantly reduced false-positive rate. This method will help find hidden micrometastases, establish clinical stage, and guide individual treatment post-surgery, suggesting potentially significant value in the clinic.
FROM THE CLINICAL EDITOR: This team of investigators prepared magnetic nanoparticles with carbon-coated pure iron as core and conjugated them with EpCAM monoclonal antibody to form immunomagnetic nanoparticles for circulating tumor cell (CTC) detection. Compared with nested RT-PCR, this method achieved the same sensitivity, but with a significantly reduced false-positive rate, paving the way to the development of a tool that enables enhanced detection of micrometastases and post-surgical treatment monitoring.
Huber RM, Rajski M, Sivasankaran B, et al.Deltex-1 activates mitotic signaling and proliferation and increases the clonogenic and invasive potential of U373 and LN18 glioblastoma cells and correlates with patient survival.
PLoS One. 2013; 8(2):e57793 [PubMed
] Free Access to Full Article Related Publications
Glioblastoma (GBM) is a highly malignant primary tumor of the central nervous system originating in glial cells. GBM results in more years of life lost than any other cancer type. Low levels of Notch receptor expression correlates with prolonged survival in various high grade gliomas independent of other markers. Different downstream pathways of Notch receptors have been identified. We tested if the Notch/Deltex pathway, which is distinct from the canonical, CSL-mediated pathway, has a role in GBM. We show that the alternative or non-canonical Notch pathway functioning through Deltex1 (DTX1) mediates key features of glioblastoma cell aggressiveness. For example, DTX1 activates the RTK/PI3K/PKB and the MAPK/ERK mitotic pathways and induces anti-apoptotic Mcl-1. The clonogenic and growth potential of established glioma cells correlated with DTX1 levels. Microarray gene expression analysis further identified a DTX1-specific, MAML1-independent transcriptional program - including microRNA-21- which is functionally linked to the changes in tumor cell aggressiveness. Over-expression of DTX1 increased cell migration and invasion correlating to ERK activation, miR-21 levels and endogenous Notch levels. In contrast to high and intermediate expressors, patients with low DTX1 levels have a more favorable prognosis. The alternative Notch pathway via DTX1 appears to be an oncogenic factor in glioblastoma and these findings offer new potential therapeutic targets.
Although aberrant Notch activation contributes to leukemogenesis in T cells, its role in acute myelogenous leukemia (AML) remains unclear. Here, we report that human AML samples have robust expression of Notch receptors; however, Notch receptor activation and expression of downstream Notch targets are remarkably low, suggesting that Notch is present but not constitutively activated in human AML. The functional role of these Notch receptors in AML is not known. Induced activation through any of the Notch receptors (Notch1-4), or through the Notch target Hairy/Enhancer of Split 1 (HES1), consistently leads to AML growth arrest and caspase-dependent apoptosis, which are associated with B cell lymphoma 2 (BCL2) loss and enhanced p53/p21 expression. These effects were dependent on the HES1 repressor domain and were rescued through reexpression of BCL2. Importantly, activated Notch1, Notch2, and HES1 all led to inhibited AML growth in vivo, and Notch inhibition via dnMAML enhanced proliferation in vivo, thus revealing the physiological inhibition of AML growth in vivo in response to Notch signaling. As a novel therapeutic approach, we used a Notch agonist peptide that led to significant apoptosis in AML patient samples. In conclusion, we report consistent Notch-mediated growth arrest and apoptosis in human AML, and propose the development of Notch agonists as a potential therapeutic approach in AML.
Notch signaling is a highly conserved cell-cell communication pathway regulating normal development and tissue homeostasis. Aberrant Notch signaling represents an important oncogenic mechanism for T cell acute lymphoblastic leukemia (T-ALL), an aggressive subset of the most common malignant childhood cancer ALL. Therefore, understanding the molecular regulation of Notch signaling is critical to identify new approaches to block aberrant Notch oncogenic activity. The family of three MAML transcriptional coactivators is crucial for Notch signaling activation. The prototypic member MAML1 is the major coactivator that regulates Notch oncogenic activities in leukemic cells. However, the molecular basis underlying MAML1 coactivator function that contributes to Notch signaling remains unclear. In this study, we performed proteomic studies and identified DDX5, an ATP-dependent DEAD-box RNA helicase, as a component of the MAML1 protein complex. DDX5 interacts with MAML1 in vitro and in vivo, and is associated with the endogenous NOTCH1 transcription activation complex in human T-ALL leukemic cells. Lentivirus-mediated short-hairpin RNA knock-down of DDX5 resulted in decreased expression of Notch target genes, reduced cell proliferation and increased apoptosis in cultured human leukemic cells with constitutive activation of Notch signaling. Also, DDX5 depletion inhibited the growth of human leukemia xenograft in nude mice. Moreover, DDX5 is highly expressed in primary human T-ALL leukemic cells based on the analyses of Oncomine and GEO databases, and Immunohistochemical staining. Our overall findings revealed a critical role of DDX5 in promoting efficient Notch-mediated transcription in leukemic cells, suggesting that DDX5 might be critical for NOTCH1-mediated T-ALL pathogenesis and thus is a potential new target for modulating the Notch signaling in leukemia.
Mastermind-like 1 (MAML1) is a transcriptional coregulator of activators in various signaling pathways, such as Notch, p53, myocyte enhancer factor 2C (MEF2C) and beta-catenin. In earlier studies, we demonstrated that MAML1 enhanced p300 acetyltransferase activity, which increased the acetylation of Notch by p300. In this study, we show that MAML1 strongly induced acetylation of the transcription factor early growth response-1 (EGR1) by p300, and increased EGR1 protein expression in embryonic kidney cells. EGR1 mRNA transcripts were also upregulated in the presence of MAML1. We show that MAML1 physically interacted with, and acted cooperatively with EGR1 to increase transcriptional activity of the EGR1 and p300 promoters, which both contain EGR1 binding sites. Bioinformatics assessment revealed a correlation between p300, EGR1 and MAML1 copy number and mRNA alterations in renal clear cell carcinoma and p300, EGR1 and MAML1 gene alterations were associated with increased overall survival. Our findings suggest MAML1 may be a component of the transcriptional networks which regulate EGR1 target genes during nephrogenesis and could also have implications for the development of renal cell carcinoma.
Activating mutations in NOTCH1, an essential regulator of T cell development, are frequently found in human T cell acute lymphoblastic leukemia (T-ALL). Despite important advances in our understanding of Notch signal transduction, the regulation of Notch functions in the nucleus remains unclear. Using immunoaffinity purification, we identified NOTCH1 nuclear partners in T-ALL cells and showed that, beyond the well-characterized core activation complex (ICN1-CSL-MAML1), NOTCH1 assembles a multifunctional complex containing the transcription coactivator AF4p12, the PBAF nucleosome remodeling complex, and the histone demethylases LSD1 and PHF8 acting through their demethylase activity to promote epigenetic modifications at Notch-target genes. Remarkably, LSD1 functions as a corepressor when associated with CSL-repressor complex and as a NOTCH1 coactivator upon Notch activation. Our work provides new insights into the molecular mechanisms that govern Notch transcriptional activity and represents glimpse into NOTCH1 interaction landscape, which will help in deciphering mechanisms of NOTCH1 functions and regulation.
Zhao S, Yang H, Zhang M, et al.Circulating tumor cells (CTCs) detected by triple-marker EpCAM, CK19, and hMAM RT-PCR and their relation to clinical outcome in metastatic breast cancer patients.
Cell Biochem Biophys. 2013; 65(2):263-73 [PubMed
] Related Publications
In order to investigate the prognostic value of circulating tumor cells (CTCs) in patients with metastatic breast cancer (MBC), the blood cells from 98 MBC patients and 60 controls were evaluated by RT-PCR to detect the presence of markers EpCAM, CK19, and hMAM. Peripheral blood was obtained from all patients with MBC before any systemic therapy. Immunofluorescence staining experiment was conducted on CTCs samples from 10 patients to investigate the coexpression of EpCAM, CK19, and hMAM. In addition, analyses were carried out for their correlation with patients' clinicopathologic features. EpCAM+, CK19+, and hMAM+ cells were detected in 50 (51.0 %), 43 (43.9 %), and 68 (69.4 %) of the 98 patients, respectively. Triple-marker-positive CTCs were detected in 86 of 98 (87.8 %) patients with a significantly higher rate than the control group. Among the 98 patients, 12 (12.2 %) patients were negative for three genes, 34 (34.7 %) positive for one gene, 29 (29.6 %) positive for any two genes, and 23 (23.5 %) positive for all three genes. Compared to single-marker detection, the triple combined marker detection exhibited significantly higher rate. Furthermore, the specificity of triple combined markers of serial test was 100 %. The expression of three genes was significantly correlated with lymph node metastasis, high histological grade, and high levels of serum CA153 and CEA. Double-immunofluorescence labeling confirmed the presence of following CTCs phenotypes: CK19+/hMAM+, CK19+/hMAM-, CK19-/hMAM+, CK19+/EpCAM+, CK19-/EpCAM+, CK19+/EpCAM-, hMAM+/EpCAM+, and hMAM+/EpCAM-. After 2 years of follow-up, the presence of CTCs with triple-marker positive in peripheral blood was an independent risk factor for reduced progression-free survival (PFS) and overall survival (OS), and the presence of CTCs before any chemotherapy predicts poor OS and PFS in patients with MBC.
Shao H, Huang Q, Liu ZJTargeting Notch signaling for cancer therapeutic intervention.
Adv Pharmacol. 2012; 65:191-234 [PubMed
] Related Publications
The Notch signaling pathway is an evolutionarily conserved, intercellular signaling cascade. The Notch proteins are single-pass receptors that are activated upon interaction with the Delta (or Delta-like) and Jagged/Serrate families of membrane-bound ligands. Association of ligand-receptor leads to proteolytic cleavages that liberate the Notch intracellular domain (NICD) from the plasma membrane. The NICD translocates to the nucleus, where it forms a complex with the DNA-binding protein CSL, displacing a histone deacetylase (HDAc)-corepressor (CoR) complex from CSL. Components of a transcriptional complex, such as MAML1 and histone acetyltransferases (HATs), are recruited to the NICD-CSL complex, leading to the transcriptional activation of Notch target genes. The Notch signaling pathway plays a critical role in cell fate decision, tissue patterning, morphogenesis, and is hence regarded as a developmental pathway. However, if this pathway goes awry, it contributes to cellular transformation and tumorigenesis. There is mounting evidence that this pathway is dysregulated in a variety of malignancies, and can behave as either an oncogene or a tumor suppressor depending upon cell context. This chapter highlights the current evidence for aberration of the Notch signaling pathway in a wide range of tumors from hematological cancers, such as leukemia and lymphoma, through to lung, skin, breast, pancreas, colon, prostate, ovarian, brain, and liver tumors. It proposes that the Notch signaling pathway may represent novel target for cancer therapeutic intervention.
Kang S, Xie J, Miao J, et al.A knockdown of Maml1 that results in melanoma cell senescence promotes an innate and adaptive immune response.
Cancer Immunol Immunother. 2013; 62(1):183-90 [PubMed
] Related Publications
Maml1 is emerging as a coactivator of many signaling pathways, including the Notch and Wnt pathways. Targeting Maml1 in melanoma cells efficiently knocks down the downstream transcriptional repressors Hey1 and Hes1, resulting in melanoma cell senescence, cellular differentiation, and increased melanin production. Significantly, higher IFNβ and chemokine gene transcripts have been observed, together with increased STAT1 and decreased STAT3 and NF-κB signaling activities. Although decreased cell proliferation contributes to slower tumor growth in vivo, the depletion of NK and CD8(+) T cells in an shMaml1-B16 tumor carrier mouse leads to more rapid tumor growth than that observed in control shC002-B16 tumors. This result demonstrates that the knockdown of Maml1 transcription and function contributes to increased immune surveillance. The knockdown of Maml1 transcription in the human melanoma cell line M537 also results in senescence, IFNβ upregulation, increased chemokine gene expression, and greater NK and CD8(+) T cell migration in a transwell system. This study demonstrated that targeting Maml1-induced tumor cell senescence and differentiation may alter the tumor microenvironment and cytokine and chemokine profiles and may also promote innate and adaptive immune cell infiltration and function.
Angiosarcomas (ASs) represent a heterogeneous group of malignant vascular tumors that may occur spontaneously as primary tumors or secondarily after radiation therapy or in the context of chronic lymphedema. Most secondary ASs have been associated with MYC oncogene amplification, whereas the role of MYC abnormalities in primary AS is not well defined. Twenty-two primary and secondary ASs were analyzed by array-comparative genomic hybridization (aCGH) and by deep sequencing of small RNA libraries. By aCGH and subsequently confirmed by fluorescence in situ hybridization, MYC amplification was identified in three out of six primary tumors and in 8 out of 12 secondary AS. We have also found MAML1 as a new potential oncogene in MYC-amplified AS. Significant upregulation of the miR-17-92 cluster was observed in MYC-amplified AS compared to AS lacking MYC amplification and the control group (other vascular tumors, nonvascular sarcomas). Moreover, MYC-amplified ASs were associated with a significantly lower expression of thrombospondin-1 (THBS1) than AS without MYC amplification or controls. Altogether, our study implicates MYC amplification not only in the pathogenesis of secondary AS but also in a subset of primary AS. Thus, MYC amplification may play a crucial role in the angiogenic phenotype of AS through upregulation of the miR-17-92 cluster, which subsequently downregulates THBS1, a potent endogenous inhibitor of angiogenesis.
Forghanifard MM, Moaven O, Farshchian M, et al.Expression analysis elucidates the roles of MAML1 and Twist1 in esophageal squamous cell carcinoma aggressiveness and metastasis.
Ann Surg Oncol. 2012; 19(3):743-9 [PubMed
] Related Publications
BACKGROUND: Epithelial-mesenchymal transition has recently attracted great attention in studying the malignant progression of cells through a converging pathway of oncogenesis and metastasis. Twist1 and Mastermind-like 1 (MAML1) are major regulators of EMT through different pathways. The aim of this study was to investigate the clinicopathological relevance of the expression of MAML-1 and Twist1 genes in esophageal squamous cell carcinoma (ESCC).
METHODS: Tumoral and corresponding normal tissues from 55 treatment-naive ESCC patients were subjected for expression analysis with quantitative real-time RT-PCR.
RESULTS: Overexpression of MAML-1 and Twist1 were significantly associated with lymph node metastasis and the surgical staging of tumor. Overexpression of Twist1 was associated with tumor depth of invasion. Mean relative expression (MRE) of MAML1 was significantly higher in patients with metastasis to lymph nodes (3.07 ± 0.51 vs. 0.86 ± 0.58, P = .008). MRE of Twist1 was significantly higher in patients with invasion of tumor to adventitia (T3, T4) (1.97 ± 0.29 vs. 0.39 ± 0.73, P = .036). In advanced stages of tumor (stage III, IV), a significantly higher MRE of Twist1 (2.47 ± 0.41 vs. 1.25 ± 0.36, P = .035) and MAML1 (3.05 ± 0.45 vs. 1.07 ± 0.59, P = .021) mRNA was observed.
CONCLUSIONS: We introduce Twist1 and MAML1 as new molecular markers of advanced tumor, which determine the characteristics and aggressive behavior of ESCC. Along with the emerging evidence of their role in different cellular processes and aberrations in various cancers, they are suggested as potentially interesting therapeutic targets to reverse a broad spectrum of functional aberrations that promote ESCC development.
Ohashi S, Natsuizaka M, Naganuma S, et al.A NOTCH3-mediated squamous cell differentiation program limits expansion of EMT-competent cells that express the ZEB transcription factors.
Cancer Res. 2011; 71(21):6836-47 [PubMed
] Free Access to Full Article Related Publications
Zinc finger E-box-binding (ZEB) proteins ZEB1 and ZEB2 are transcription factors essential in TGF-β-mediated senescence, epithelial-to-mesenchymal transition (EMT), and cancer stem cell functions. ZEBs are negatively regulated by members of the miR-200 microRNA family, but precisely how tumor cells expressing ZEBs emerge during invasive growth remains unknown. Here, we report that NOTCH3-mediated signaling prevents expansion of a unique subset of ZEB-expressing cells. ZEB expression was associated with the lack of cellular capability of undergoing NOTCH3-mediated squamous differentiation in human esophageal cells. Genetic inhibition of the Notch-mediated transcriptional activity by dominant-negative Mastermind-like 1 (DNMAML1) prevented squamous differentiation and induction of Notch target genes including NOTCH3. Moreover, DNMAML1-enriched EMT-competent cells exhibited robust upregulation of ZEBs, downregulation of the miR-200 family, and enhanced anchorage-independent growth and tumor formation in nude mice. RNA interference experiments suggested the involvement of ZEBs in anchorage-independent colony formation, invasion, and TGF-β-mediated EMT. Invasive growth and impaired squamous differentiation were recapitulated upon Notch inhibition by DNMAML1 in organotypic three-dimensional culture, a form of human tissue engineering. Together, our findings indicate that NOTCH3 is a key factor limiting the expansion of ZEB-expressing cells, providing novel mechanistic insights into the role of Notch signaling in the cell fate regulation and disease progression of esophageal squamous cancers.
Kuncharin Y, Sangphech N, Kueanjinda P, et al.MAML1 regulates cell viability via the NF-κB pathway in cervical cancer cell lines.
Exp Cell Res. 2011; 317(13):1830-40 [PubMed
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The Notch signaling pathway plays important roles in tumorigenesis in a context-dependent manner. In human cervical cancer, alterations in Notch signaling have been reported, and both tumor-suppressing and tumor-promoting roles of Notch signaling have been proposed; however, the precise molecular mechanisms governing these roles in cervical cancer remain controversial. MAML is a transcriptional co-activator originally identified by its role in Notch signaling. Recent evidence suggests that it also plays a role in other signaling pathways, such as the p53 and β-catenin pathways. MAML is required for stable formation of Notch transcriptional complexes at the promoters of Notch target genes. Chromosomal translocations affecting MAML have been shown to promote tumorigenesis. In this study, we used a truncated dominant-negative MAML1 (DN-MAML) to investigate the role of MAML in HPV-positive cervical cancer cell lines. Three human cervical cancer cell lines (HeLa, SiHa and CaSki) expressed all Notch receptors and the Notch target genes Hes1 and MAML1. Among these 3 cell lines, constitutive appearance of cleaved Notch1 was found only in CaSki cells, which suggests that Notch1 is constitutively activated in this cell line. Gamma secretase inhibitor (GSI) treatment, which suppresses Notch receptor activation, completely abrogated this form of Notch1 but had no effect on cell viability. Overexpression of DN-MAML by retroviral transduction in CaSki cells resulted in significant decreases in the mRNA levels of Hes1 and Notch1 but had no effects on the levels of MAML1, p53 or HPV E6/E7. DN-MAML expression induced increased viability of CaSki cells without any effect on cell cycle progression or cell proliferation. In addition, clonogenic assay experiments revealed that overexpression of DN-MAML resulted in increased colony formation compared to the overexpression of the control vector. When the status of the NF-κB pathway was investigated, CaSki cells overexpressing DN-MAML exhibited loss of phospho-IκBα, decreased total IκBα and nuclear localization of NF-κB p65, which suggests that the NF-κB pathway is hyperactivated. Furthermore, increased level of cleaved Notch1 was detected when DN-MAML was expressed. When DN-MAML-overexpressing cells were treated with GSI, significantly decreased cell viability was observed, indicating that inhibition of Notch signaling using GSI treatment and DN-MAML expression negatively affects cell viability. Taken together, targeting Notch signaling using DN-MAML and GSI treatment may present a novel method to control cell viability in cervical cancer cells.
The ZMYM2-FGFR1 (formerly known as ZNF198-FGFR1) fusion kinase induces stem cell leukemia-lymphoma syndrome (SCLL), a hematologic malignancy characterized by rapid transformation to acute myeloid leukemia and T-lymphoblastic lymphoma. In the present study, we demonstrate frequent, constitutive activation of Notch1 and its downstream target genes in T-cell lymphomas that arose in a murine model of ZMYM2-FGFR1 SCLL. Notch up-regulation was also demonstrated in human SCLL- and FGFR1OP2-FGFR1-expressing KG-1 cells. To study the role of Notch in T-cell lymphomagenesis, we developed a highly tumorigenic cell line from ZMYM2-FGFR1-expressing cells. Pharmacologic inhibition of Notch signaling in these cells using γ-secretase inhibitors significantly delayed leukemogenesis in vivo. shRNA targeting of Notch1, as well as c-promoter-binding factor 1 (CBF1) and mastermind-like 1 (MAML1), 2 essential cofactors involved in transcriptional activation of Notch target genes, also significantly delayed or inhibited tumorigenesis in vivo. Mutation analysis demonstrated that 5' promoter deletions and alternative promoter usage were responsible for constitutive activation of Notch1 in all T-cell lymphomas. These data demonstrate the importance of Notch signaling in the etiology of SCLL, and suggest that targeting this pathway could provide a novel strategy for molecular therapies to treat SCLL patients.
BACKGROUND: The presence of circulating tumor cells (CTC) in the peripheral blood of cancer patients has been described for various solid tumors and their clinical relevance has been shown. CTC detection based on the analysis of epithelial antigens might be hampered by the genetic heterogeneity of the primary tumor and loss of epithelial antigens. Therefore, we aimed to identify new gene markers for the PCR-based detection of CTC in female cancer patients.
METHODS: Gene expression of 38 cancer cell lines (breast, ovarian, cervical and endometrial) and of 10 peripheral blood mononuclear cell (PBMC) samples from healthy female donors was measured using microarray technology (Applied Biosystems). Differentially expressed genes were identified using the maxT test and the 50% one-sided trimmed maxT-test. Confirmatory RT-qPCR was performed for 380 gene targets using the AB TaqMan® Low Density Arrays. Then, 93 gene targets were analyzed using the same RT-qPCR platform in tumor tissues of 126 patients with primary breast, ovarian or endometrial cancer. Finally, blood samples from 26 healthy women and from 125 patients (primary breast, ovarian, cervical, or endometrial cancer, and advanced breast cancer) were analyzed following OncoQuick enrichment and RNA pre-amplification. Likewise, hMAM and EpCAM gene expression was analyzed in the blood of breast and ovarian cancer patients. For each gene, a cut-off threshold value was set at three standard deviations from the mean expression level of the healthy controls to identify potential markers for CTC detection.
RESULTS: Six genes were over-expressed in blood samples from 81% of patients with advanced and 29% of patients with primary breast cancer. EpCAM gene expression was detected in 19% and 5% of patients, respectively, whereas hMAM gene expression was observed in the advanced group (39%) only. Multimarker analysis using the new six gene panel positively identified 44% of the cervical, 64% of the endometrial and 19% of the ovarian cancer patients.
CONCLUSIONS: The panel of six genes was found superior to EpCAM and hMAM for the detection of circulating tumor cells in the blood of breast cancer, and they may serve as potential markers for CTC derived from endometrial, cervical, and ovarian cancers.
Bell D, Holsinger CF, El-Naggar AKCRTC1/MAML2 fusion transcript in central mucoepidermoid carcinoma of mandible--diagnostic and histogenetic implications.
Ann Diagn Pathol. 2010; 14(6):396-401 [PubMed
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Intraosseous salivary gland carcinomas are extremely rare, comprising only 2% to 3% of all mucoepidermoid carcinomas (MECs) reported. The t(11;19) translocation and its CRTC1/MAML1 fusion transcript have been identified in MEC at different sites and are believed to be associated with the development of a subset of these tumors. However, the status of the fusion transcript has not been reported in intraosseous MEC. Here, we report 3 examples of central MEC of the mandible, including a case with a history of primary retromolar MEC. Reverse transcriptase-polymerase chain reaction and DNA sequencing analyses of the microdissected components of these tumors were used for the detection and verification of the fusion transcript. We identified, for the first time, the t(11;19) fusion gene transcript in central MEC, including in the previous primary retromolar MEC. No fusion transcript was detected in the second primary noncentral MEC or in another central MEC. The results indicate that central MEC can manifest the fusion transcript. This finding may have diagnostic and histogenetic roles in the future analysis of this entity.
Chen J, Imanaka N, Chen J, Griffin JDHypoxia potentiates Notch signaling in breast cancer leading to decreased E-cadherin expression and increased cell migration and invasion.
Br J Cancer. 2010; 102(2):351-60 [PubMed
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BACKGROUND: Epithelial-to-mesenchymal transition (EMT) is associated with decreased adhesion and acquisition of metastatic potential of breast cancer cells. Epithelial-to-mesenchymal transition is mediated, in part, by two transcription repressors, Snail and Slug, that are known to be targets of the Notch signaling pathway, and JAGGED1-induced Notch activation increases EMT. However, the events that lead to increased Notch activity during EMT of breast cancer cells are unknown.
METHODS: The accumulation of hypoxia inducible factors (HIFs) under hypoxia was detected by western blot analysis, and their effects on Notch signaling were measured by an in vitro Notch reporter assay. The expression of Notch target genes under hypoxia was tested by real-time PCR. The knockdown of HIF-1alpha was mediated by retroviral delivery of shRNA. The expression of Slug and Snail under hypoxia was measured by real-time PCR. Breast cancer cell migration and invasion under hypoxia were tested with cell migration and invasion kits.
RESULTS: Hypoxia increased the expression of Notch target genes such as HES1 and HEY1 in breast cancer cells, as was expression of Notch receptors and ligands. The mechanism is likely to involve the accumulation of HIF-1alpha and HIF-2alpha in these cells by hypoxia, which synergised with the Notch co-activator MAML1 in potentiating Notch activity. Hypoxia inducible factor-1alpha was found to bind to HES1 promoter under hypoxia. Knockdown of HIF-1alpha with shRNA inhibited both HES1 and HEY1 expression under hypoxia. Hypoxia increased the expression of Slug and Snail, and decreased the expression of E-cadherin, hallmarks of EMT. Notch pathway inhibition abrogated the hypoxia-mediated increase in Slug and Snail expression, as well as decreased breast cancer cell migration and invasion.
CONCLUSION: Hypoxia-mediated Notch signaling may have an important role in the initiation of EMT and subsequent potential for breast cancer metastasis.
Direct inhibition of transcription factor complexes remains a central challenge in the discipline of ligand discovery. In general, these proteins lack surface involutions suitable for high-affinity binding by small molecules. Here we report the design of synthetic, cell-permeable, stabilized alpha-helical peptides that target a critical protein-protein interface in the NOTCH transactivation complex. We demonstrate that direct, high-affinity binding of the hydrocarbon-stapled peptide SAHM1 prevents assembly of the active transcriptional complex. Inappropriate NOTCH activation is directly implicated in the pathogenesis of several disease states, including T-cell acute lymphoblastic leukaemia (T-ALL). The treatment of leukaemic cells with SAHM1 results in genome-wide suppression of NOTCH-activated genes. Direct antagonism of the NOTCH transcriptional program causes potent, NOTCH-specific anti-proliferative effects in cultured cells and in a mouse model of NOTCH1-driven T-ALL.
Approximately 80% of breast cancers express the estrogen receptor-alpha (ERalpha) and are treated with anti-estrogens. Resistance to these agents is a major cause of mortality. We have shown that estrogen inhibits Notch, whereas anti-estrogens or estrogen withdrawal activate Notch signaling. Combined inhibition of Notch and estrogen signaling has synergistic effects in ERalpha-positive breast cancer models. However, the mechanisms whereby Notch-1 promotes the growth of ERalpha-positive breast cancer cells are unknown. Here, we demonstrate that Notch-1 increases the transcription of ERalpha-responsive genes in the presence or absence of estrogen via a novel chromatin crosstalk mechanism. Our data support a model in which Notch-1 can activate the transcription of ERalpha-target genes via IKKalpha-dependent cooperative chromatin recruitment of Notch-CSL-MAML1 transcriptional complexes (NTC) and ERalpha, which promotes the recruitment of p300. CSL binding elements frequently occur in close proximity to estrogen-responsive elements (EREs) in the human and mouse genomes. Our observations suggest that a hitherto unknown Notch-1/ERalpha chromatin crosstalk mediates Notch signaling effects in ERalpha-positive breast cancer cells and contributes to regulate the transcriptional functions of ERalpha itself.