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Herbst A, Bommer GT, Kriegl L, Jung A, Behrens A, Csanadi E, Gerhard M, Bolz C, Riesenberg R, Zimmermann W, Dietmaier W, Wolf I, Brabletz T, Göke B, Kolligs FT. ITF-2 is disrupted via allelic loss of chromosome 18q21, and ITF-2B expression is lost at the adenoma-carcinoma transition. Gastroenterology 2009; 137:639-48, 648.e1-9. [PMID: 19394332 DOI: 10.1053/j.gastro.2009.04.049] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Revised: 04/10/2009] [Accepted: 04/13/2009] [Indexed: 12/02/2022]
Abstract
BACKGROUND & AIMS The ubiquitously expressed basic helix-loop-helix transcription factor ITF-2B has an important role in differentiation processes, and its transcription is regulated by beta-catenin. The ITF-2 gene is located in the chromosomal region 18q21; allelic loss of this locus occurs in 70% of colorectal cancers. We analyzed the expression, regulation, and function of ITF-2B in colorectal carcinogenesis. METHODS The loss-of-heterozygosity (LOH) status of 18q21 and expression of ITF-2B were studied in colorectal carcinomas using polymerase chain reaction-based methods and immunohistochemistry. The biologic effects of ITF-2B were studied in colorectal cancer cells. Reporter gene assays and chromatin immunoprecipitation were utilized to analyze effects of ITF-2B on gene transcription. RESULTS ITF-2B is strongly expressed in colon adenomas but frequently down-regulated in carcinomas because of LOH at 18q21. ITF-2B induces cell cycle arrest and regulates the expression of p21(Cip1) via newly identified E-boxes in the CDKN1A gene, independently of p53. Loss of ITF-2B expression correlates with loss of p21(Cip1) expression in primary colon carcinomas. CONCLUSIONS Accumulation of mutations and allelic losses are driving forces of colorectal carcinogenesis. ITF-2B, which is up-regulated during early colorectal carcinogenesis because of loss of adenomatous polyposis coli, is a target for LOH on chromosome 18q, along with deleted in colorectal carcinoma and Smad4. This finding, along with the fact that ITF-2B is a regulator of the key cell cycle inhibitor p21(Cip1), indicates that ITF-2B is a tumor suppressor that has an important function at the adenoma to carcinoma transition.
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Affiliation(s)
- Andreas Herbst
- Department of Medicine II, University of Munich, Munich, Germany
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52
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Interfering with multimerization of netrin-1 receptors triggers tumor cell death. Cell Death Differ 2009; 16:1344-51. [PMID: 19543238 DOI: 10.1038/cdd.2009.75] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Netrin-1 was recently proposed to control tumorigenesis by inhibiting apoptosis induced by the dependence receptors DCC (Deleted in colorectal cancer) and UNC5H. Although the loss of these dependence receptors' expression has been described as a selective advantage for tumor growth and progression in numerous cancers, recent observations have shown that some tumors may use an alternative strategy to block dependence receptor-induced programmed cell death: the autocrine expression of netrin-1. This alternative strategy has been observed in a large fraction of aggressive breast cancers, neuroblastoma, pancreatic adenocarcinoma, and lung cancer. This observation is of potential interest regarding future targeted therapy, as in such cases interfering with the ability of netrin-1 to inhibit DCC or UNC5H-induced cell death is associated with apoptosis of netrin-1-expressing tumor cells in vitro, and with inhibition of tumor growth or metastasis in different animal tumor models. The understanding of the mechanism by which netrin-1 inhibits cell death is therefore of interest. Here, we show that netrin-1 triggers the multimerization of both DCC and UNC5H2 receptors, and that multimerization of the intracellular domain of DCC and UNC5H2 is the critical step to inhibit the proapoptotic effects of both of these receptors. Taking advantage of this property, we utilized a recombinant specific domain of DCC that (i) interacts with netrin-1 and (ii) inhibits netrin-1-induced multimerization, to trigger apoptosis in netrin-dependent tumor cells.
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53
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Effect of COX2 -765G>C and c.3618A>G polymorphisms on the risk and survival of sporadic colorectal cancer. Cancer Causes Control 2009; 20:1421-9. [DOI: 10.1007/s10552-009-9368-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2009] [Accepted: 05/11/2009] [Indexed: 12/01/2022]
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Dalkic E, Nash DEW, Fassia MK, Chan C. Integrative analysis of cancer pathway progression and coherence. Proteomics Clin Appl 2009; 3:473-85. [PMID: 21136972 DOI: 10.1002/prca.200800074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2008] [Indexed: 11/07/2022]
Abstract
We analyzed the cancer pathways in the KEGG (Kyoto Encyclopedia of Genes and Genomes) database. The database provides a collective of signaling pathway members involved in cancer progression. However, the KEGG cancer pathways, unlike signaling pathways, have not been analyzed extensively with gene expression and mutation data. We transformed the colorectal cancer pathway into discrete X and Y scales and analyzed the relative expression levels of adenoma and carcinoma samples as well as the distribution of mutation targets. The X scale corresponds to the downstream location in a pathway, whereas the Y scale corresponds to the stage of the tumor. The gene expression values of the early stage pathway members are significantly higher than of the rest of the pathway members in colorectal adenoma tissues. The colorectal cancer pathway shows some degree of coherence in the carcinoma samples. The correlated gene pairs responsible for the coherence of the colorectal cancer pathway in the carcinoma samples are supported, in part, by the literature and may suggest novel regulatory associations. Finally, there are more mutation targets in the nucleus as well as the late tumor stages of the KEGG colorectal cancer pathway.
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Affiliation(s)
- Ertugrul Dalkic
- Center for Systems Biology, Michigan State University, East Lansing, MI, USA; Cellular and Molecular Biology Lab, Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI, USA; Cell and Molecular Biology Program, Michigan State University, East Lansing, MI, USA
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Derks S, Bosch LJW, Niessen HEC, Moerkerk PTM, van den Bosch SM, Carvalho B, Mongera S, Voncken JW, Meijer GA, de Bruïne AP, Herman JG, van Engeland M. Promoter CpG island hypermethylation- and H3K9me3 and H3K27me3-mediated epigenetic silencing targets the deleted in colon cancer (DCC) gene in colorectal carcinogenesis without affecting neighboring genes on chromosomal region 18q21. Carcinogenesis 2009; 30:1041-8. [PMID: 19329758 DOI: 10.1093/carcin/bgp073] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Chromosomal loss of 18q21 is a frequent event in colorectal cancer (CRC) development, suggesting that this region harbors tumor suppressor genes (TSGs). Several candidate TSGs, among which methyl-CpG-binding domain protein 1 (MBD1), CpG-binding protein CXXC1, Sma- and Mad-related protein 4 (SMAD4), deleted in colon cancer (DCC) and methyl-CpG-binding domain protein 2 (MBD2) are closely linked on a 4-Mb DNA region on chromosome18q21. As TSGs can be epigenetically silenced, this study investigates whether MBD1, CXXC1, SMAD4, DCC and MBD2 are subject to epigenetic silencing in CRC. Methylation-specific polymerase chain reaction and sodium bisulfite sequencing of these genes show that DCC, but not MBD1, CXXC1, SMAD4 and MBD2, has promoter CpG island methylation in CRC cell lines and tissues {normal mucosa [29.5% (18/61)], adenomas [81.0% (47/58)] and carcinomas [82.7% (62/75)] (P = 8.6 x 10(-9))} that is associated with reduced DCC expression, independent of 18q21 loss analyzed by multiplex ligation-dependent probe amplification. Reduced gene expression of CXXC1, SMAD4 and MBD2 correlates with 18q21 loss in CRC cell lines (P = 0.04, 0.02 and 0.02, respectively). Treatment with the demethylating agent 5-aza-2'-deoxycytidine, but not with the histone deacetylase inhibitor trichostatin A exclusively restored DCC expression in CRC cell lines. Chromatin immunoprecipitation studies reveal that the DCC promoter is marked with repressive histone-tail marks H3K9me3 and H3K27me3, whereas activity related H3K4me3 was absent. Only active epigenetic marks were detected for MBD1, CXXC1, SMAD4 and MBD2. This study demonstrates specific epigenetic silencing of DCC in CRC as a focal process not affecting neighboring genes on chromosomal region 18q21.
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Affiliation(s)
- Sarah Derks
- Department of Pathology, Maastricht University Medical Center, The Netherlands
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56
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Delloye-Bourgeois C, Brambilla E, Coissieux MM, Guenebeaud C, Pedeux R, Firlej V, Cabon F, Brambilla C, Mehlen P, Bernet A. Interference with netrin-1 and tumor cell death in non-small cell lung cancer. J Natl Cancer Inst 2009; 101:237-47. [PMID: 19211441 DOI: 10.1093/jnci/djn491] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Netrin-1 may promote colorectal and breast tumorigenesis, by inhibiting apoptosis induced by its dependence receptors, deleted in colorectal cancer (DCC) and uncoordinated-5-homolog (UNC5H). The status of netrin-1 and its receptors in non-small cell lung cancer (NSCLC) was unknown. METHODS The levels of netrin-1 and its receptors were analyzed in a panel of 92 NSCLC and 25 human lung cancer cell lines by quantitative reverse transcription-polymerase chain reaction and immunohistochemistry. In lung cancer cell lines that express netrin-1, the expression of netrin-1 was inhibited by using small interfering RNA (siRNA), or interference with netrin-1 was performed by treatment with a decoy recombinant DCC ectodomain protein (DCC-5Fbn). Cell death was monitored with a trypan blue exclusion assay or by measuring caspase-3 activity. The effect of netrin-1 interference on tumor growth was analyzed by DCC-5Fbn intratumoral or netrin-1 siRNA intraperitoneal injection in mice engrafted with lung cancer cell lines. All statistical tests were two-sided. RESULTS High levels of netrin-1 were found in 43 of the 92 NSCLC tumor samples (47%). Interference with netrin-1 in human lung cancer cell lines was associated with UNC5H-mediated cell death in vitro (percentage of cell death in untreated and in DCC-5Fbn-treated cells = 8% and 26%, respectively, difference = 18%, 95% confidence interval [CI] = 10% to 26%; P = .049) and with lung tumor growth inhibition and/or regression in xenografted nude mice (12 mice in DCC-5Fbn-treated group and 13 mice in control group). Mean volume of control and DCC-5Fbn-treated tumors on day 46 was 489 and 84 mm(3), respectively (difference = 404 mm(3), 95% CI = 145 to 664 mm(3); P < .001). CONCLUSIONS Almost half of the NSCLC tissue samples examined expressed high levels of netrin-1. Extracellular targeting of the interaction between netrin-1 and UNC5H may be a promising therapeutic approach for NSCLCs that express netrin-1.
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Affiliation(s)
- Céline Delloye-Bourgeois
- Apoptosis, Cancer and Development Laboratory-Equipe labellisée La Ligue, CNRS UMR5238, Université de Lyon, Centre Léon Bérard, Lyon, France
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Xiong CL, Huang Y. Advances in biological characteristics of p53 gene and its role in gastrointestinal tumors. Shijie Huaren Xiaohua Zazhi 2008; 16:3648-3653. [DOI: 10.11569/wcjd.v16.i32.3648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
With the progression of current genetic research, tumor-specific gene detection has become an important method to identify tumor patients; meanwhile, gene therapy or gene-targeted therapy, which is becoming a novel approach of tumor treatment, has brought a new hope for the final cure of malignant tumors. In this article, we review the characteristics of tumor-associated gene p53 and its role in gastrointestinal tumors.
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Paradisi A, Maisse C, Bernet A, Coissieux MM, Maccarrone M, Scoazec JY, Mehlen P. NF-kappaB regulates netrin-1 expression and affects the conditional tumor suppressive activity of the netrin-1 receptors. Gastroenterology 2008; 135:1248-57. [PMID: 18692059 DOI: 10.1053/j.gastro.2008.06.080] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2008] [Revised: 06/03/2008] [Accepted: 06/26/2008] [Indexed: 12/02/2022]
Abstract
BACKGROUND & AIMS Netrin-1 was recently proposed to play a crucial role during colorectal tumorigenesis by regulating apoptosis. Because netrin-1 receptors belong to the family of dependence receptors, a selective advantage for a tumor is either to lose netrin-1 receptors or to gain autocrine expression of netrin-1. We have investigated whether netrin-1 is up-regulated in colorectal cancer and have searched for a link between NF-kappaB activation and netrin-1 up-regulation. METHODS The level of netrin-1, netrin-1 receptors, ie, DCC, UNC5H1, UNC5H2, UNC5H3, and the proinflammatory markers cyclooxygenase-2 and inhibitor of nuclear factor-kappaB (IkappaB) alpha were analyzed in a panel of 59 primary sporadic colorectal carcinomas. Netrin-1 expression was investigated in tumor cells and in mouse colonic crypts in response to NF-kappaB activation but also in a mouse model of inflammation-induced colorectal cancer. Binding of NF-kappaB to netrin-1 promoter and effect of NF-kappaB activation to the proapoptotic activity of UNC5H2 were also analyzed. RESULTS We show that colorectal tumors with a gain of netrin-1 are tumors that display increased activation of the NF-kappaB pathway. Moreover, netrin-1 up-regulation, which is associated with tumor formation in mice, is observed in mouse colonic crypts in response to NF-kappaB activation but also in a mouse model of inflammation-induced colorectal cancer. We demonstrate that the netrin-1 gene is a direct transcriptional target of NF-kappaB. We show that NF-kappaB-induced netrin-1 expression inhibits proapoptotic activity of the netrin-1 receptors. CONCLUSIONS We propose that NF-kappaB activation that occurs in response to inflammation confers a selective advantage for tumor development through NF-kappaB-mediated netrin-1 up-regulation.
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Affiliation(s)
- Andrea Paradisi
- Apoptosis, Cancer and Development Laboratory-Equipe Labellisée La Ligue, CNRS UMR 5238, Université de Lyon, Centre Léon Bérard, Lyon, France
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59
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Orlando FA, Tan D, Baltodano JD, Khoury T, Gibbs JF, Hassid VJ, Ahmed BH, Alrawi SJ. Aberrant crypt foci as precursors in colorectal cancer progression. J Surg Oncol 2008; 98:207-13. [PMID: 18623110 DOI: 10.1002/jso.21106] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Colorectal cancer progression originates when accumulated genetic and epigenetic alterations cause genomic instability and a malignant phenotype. Subsequent molecular pathway deregulation leads to histopathologic changes that are clinically evident as aberrant crypt foci (ACF) and visualized by high-magnification chromoscopic colonoscopy. ACF are biomarkers of increased colorectal cancer risk, particularly those with dysplastic features. Genetic profiling using genomic instability, loss of heterozygosity, and methylation analysis has revealed a minority population of ACF genotypically analogous to cancer.
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Affiliation(s)
- Frank A Orlando
- Department of Surgery, University of Florida, Gainesville, Florida 32610, USA.
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60
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Netrin-1 is a survival factor during commissural neuron navigation. Proc Natl Acad Sci U S A 2008; 105:14465-70. [PMID: 18796601 DOI: 10.1073/pnas.0803645105] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
DCC (Deleted in Colorectal Cancer) is a putative tumor suppressor whose expression is lost in numerous cancers and whose tumor suppressor activity appears to be dependent on its ability to trigger apoptosis when disengaged by its ligand netrin-1. In this sense, netrin-1 is a survival factor that controls tumorigenesis. However, netrin-1 is also the prototypical axon guidance cue and has been shown to orient many neurons or axons, especially commissural axons, during spinal cord development. Here we show that netrin-1 is not only an attractive cue for developing commissural axons but also promotes their survival. In primary neuronal culture, in mice or in chick embryos, netrin-1 inhibits the proapoptotic activity of DCC in developing commissural neurons. Thus, adequate commissural neurons navigation requires both the attractive activity of netrin-1 and the anti-apoptotic function of this cue.
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Tan HK, Saulnier P, Auperin A, Lacroix L, Casiraghi O, Janot F, Fouret P, Temam S. Quantitative methylation analyses of resection margins predict local recurrences and disease-specific deaths in patients with head and neck squamous cell carcinomas. Br J Cancer 2008; 99:357-63. [PMID: 18594522 PMCID: PMC2480979 DOI: 10.1038/sj.bjc.6604478] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
This study sought to determine whether the presence of hypermethylated genes in the surgical margins can predict local recurrences in head and neck squamous cell carcinomas (HNSCCs). We prospectively collected tumour and surgical margin specimens from patients with HNSCCs who had undergone surgical resections. Quantitative methylation-specific PCR (QMSP) of CDKN2A, CCNA1 and DCC were performed in these specimens and correlated with clinical data. Of the 42 patients eligible for the study, 27 were hypermethylation informative for the above three genes. This latter group was associated with longer disease-free survivals (P=0.007) and longer time to disease-specific deaths (P=0.004). Multivariate analyses confirmed hypermethylation non-informative tumours as an independent prognosticating factor for disease-specific deaths (risk ratio 3.8, P=0.026). Quantitative MSP of the margins of 24 hypermethylation informative tumours revealed that 11 patients had molecularly positive margins, of which, five developed disease-specific events (DSEs, three local recurrences and two metastases), compared to none in patients with molecularly negative margins, after a median follow-up of 48 months. Log-rank analyses showed that molecularly positive margins were associated with shorter time to local recurrences and disease-specific deaths (P=0.03 and 0.01, respectively). This study demonstrated that QMSP of hypermethylated promoters in surgical margins predicted all the local recurrences in our series of HNSCC patients. We have also identified hypermethylation non-informative tumours as an independent predictor for the development of DSEs.
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Affiliation(s)
- H K Tan
- Department of Head and Neck Surgery, Institut Gustave-Roussy, 39, Rue Camille Desmoulins, Villejuif 94805, France
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63
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Dual neurotoxic and neuroprotective role of metabotropic glutamate receptor 1 in conditions of trophic deprivation - possible role as a dependence receptor. Neuropharmacology 2008; 55:500-8. [PMID: 18619982 DOI: 10.1016/j.neuropharm.2008.06.039] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 06/04/2008] [Accepted: 06/12/2008] [Indexed: 12/22/2022]
Abstract
Group I metabotropic glutamate receptors have been often implicated in various models of neuronal toxicity, however, the role played by the individual receptors and their putative mechanisms of action contributing to neurotoxicity or neuroprotection remain unclear. Here, using primary cultures of rat cerebellar granule cells and mouse cortical neurons, we show that conditions of trophic deprivation increased mGlu1 expression which correlated with the developing cell death. The inhibition of mGlu1 expression by specific siRNA attenuated toxicity, while adenovirus-mediated overexpression of mGlu1 resulted in increased cell death, indicating a causal relationship between the level of receptor expression and neuronal survival. In pharmacological experiments selective mGlu1 antagonists failed to protect from mGlu1-induced cell death, instead, neuronal survival was promoted by glutamate acting at mGlu1 receptors. Such properties are characteristics of a novel heterogeneous family of dependence receptors which control neuronal apoptosis. Our findings indicate that increased expression of mGlu1 in neurons creates a state of cellular dependence on the presence of its endogenous agonist glutamate. We propose a new role and a new mechanism for mGlu1 action. This receptor may play a crucial role in determining the fate of individual neurons during the development of the nervous system.
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64
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The neogenin intracellular domain regulates gene transcription via nuclear translocation. Mol Cell Biol 2008; 28:4068-79. [PMID: 18391016 DOI: 10.1128/mcb.02114-07] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Neogenin is a multifunctional receptor implicated in axon navigation, neuronal differentiation, morphogenesis, and cell death. Very little is known about signaling downstream of neogenin. Because we found that the neogenin intracellular domain (NeICD) interacts with nuclear proteins implicated in transcription regulation, we investigated further whether neogenin signals similarly to the Notch receptor. We show here that neogenin is cleaved by gamma-secretase, an event that releases the complete NeICD. We also describe that NeICD is located at the nucleus, a feature regulated through a balance between nuclear import and export. NeICD triggers gene reporter transactivation and associates with nuclear chromatin. Direct transcriptional targets of NeICD were determined and were shown to be up-regulated in the presence of neogenin ligand. Together, we reveal here a novel aspect of neogenin signaling that relies on the direct implication of its intracellular domain in transcriptional regulation.
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Netrin-1 expression confers a selective advantage for tumor cell survival in metastatic breast cancer. Proc Natl Acad Sci U S A 2008; 105:4850-5. [PMID: 18353983 DOI: 10.1073/pnas.0709810105] [Citation(s) in RCA: 169] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Netrin-1, an axon navigation cue was proposed to play a crucial role during colorectal tumorigenesis by regulating apoptosis. The netrin-1 receptors DCC and UNC5H were shown to belong to the family of dependence receptors that share the ability to induce apoptosis in the absence of their ligands. Such a trait confers on these receptors a tumor suppressor activity. Expression of one of these dependence receptors at the surface of a tumor cell is indeed speculated to render this cell dependent on ligand availability for its survival, hence inhibiting uncontrolled cell proliferation or metastasis. Consequently, it is a selective advantage for a tumor cell to lose this dependence receptor activity, as previously described with losses of DCC and UNC5H expression in human cancers. However, the model predicts that a similar advantage may be obtained by gaining autocrine expression of the ligand. We describe here that, unlike human nonmetastatic breast tumors, a large fraction of metastatic breast cancers overexpress netrin-1. Moreover, we show that netrin-1-expressing mammary metastatic tumor cell lines undergo apoptosis when netrin-1 expression is experimentally decreased or when decoy soluble receptor ectodomains are added. Such treatments prevent metastasis formation both in a syngenic mouse model of lung colonization of a mammary cancer cell line and in a model of spontaneous lung metastasis of xenografted human breast tumor. Thus, netrin-1 expression observed in a large fraction of human metastatic breast tumors confers a selective advantage for tumor cell survival and potentially represents a promising target for alternative anticancer therapeutic strategies.
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66
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Freitas C, Larrivée B, Eichmann A. Netrins and UNC5 receptors in angiogenesis. Angiogenesis 2008; 11:23-9. [PMID: 18266062 DOI: 10.1007/s10456-008-9096-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2008] [Accepted: 01/22/2008] [Indexed: 12/24/2022]
Abstract
Both neuronal and vascular development require guidance to establish a precise branching pattern of these systems in the vertebrate body. Several molecules implicated in axon navigation have also been shown to regulate vessel sprouting. Among these guidance cues, Netrins constitute a family of diffusible molecules with a bifuncional role in axon pathfinding. Recent findings implicate Netrins in other developmental processes, including vascular development. We here review recent studies and discuss the possible dual function of Netrins and its receptors during branching of blood vessels in developmental and pathological angiogenesis.
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SHIN SUNGKWAN, NAGASAKA TAKESHI, JUNG BARBARAH, MATSUBARA NAGAHIDE, HO KIM WON, CARETHERS JOHNM, BOLAND CRICHARD, GOEL AJAY. Epigenetic and genetic alterations in Netrin-1 receptors UNC5C and DCC in human colon cancer. Gastroenterology 2007; 133:1849-57. [PMID: 18054557 PMCID: PMC4139066 DOI: 10.1053/j.gastro.2007.08.074] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Accepted: 08/02/2007] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS DCC and UNC5C, Netrin-1 dependence receptors, perform an important role in intestinal epithelial biology. Both receptors frequently are down-regulated in colorectal cancer (CRC). Although CRCs frequently lose DCC owing to deletions at 18q, the mechanism for the UNC5C loss is poorly understood. We hypothesized that UNC5C is silenced epigenetically in CRC, and that there are interactions between losses of UNC5C and DCC in colorectal tumorigenesis. METHODS Gene expression and epigenetic analysis of UNC5C was examined in 8 CRC cell lines, 147 sporadic CRCs with corresponding normal mucosa, and 52 adenomatous polyps (APs). Allelic imbalances at DCC were determined in CRCs. The molecular analyses were compared with genetic and clinicopathologic features. RESULTS All CRC cell lines showed UNC5C methylation and an associated loss of gene expression. Treatment with 5-Aza-2'-deoxycytidine resulted in restoration of gene transcription. UNC5C methylation was significantly higher in CRCs (76.2%) and APs (63.5%) than in corresponding normal mucosa (6%; P < .0001). Allelic imbalance at DCC was observed in 61% of CRCs. Overall, 89.3% of CRCs had alterations of one of the dependence receptors. UNC5C methylation occurred predominantly in the earlier lesions (APs and early CRCs), whereas DCC losses were more often in advanced CRCs. CONCLUSIONS The majority of CRCs harbor defects in Netrin-1 receptors, emphasizing the importance of this growth regulatory pathway in cancer. Furthermore, the timing of the molecular alterations in the Netrin-1 receptors is not random because UNC5C inactivation occurs early, whereas DCC losses occurs in later stages of multistep colorectal carcinogenesis.
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Affiliation(s)
- SUNG KWAN SHIN
- Division of Gastroenterology, Department of Internal Medicine, Baylor University Medical Center, Dallas, Texas
| | - TAKESHI NAGASAKA
- Division of Gastroenterology, Department of Internal Medicine, Baylor University Medical Center, Dallas, Texas
| | - BARBARA H. JUNG
- Department of Gastroenterology and Moores Cancer Center, University of California San Diego, La Jolla, California
| | - NAGAHIDE MATSUBARA
- Department of Gastroenterological Surgery, Transplant and Surgical Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - WON HO KIM
- Division of Gastroenterology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, South Korea
| | - JOHN M. CARETHERS
- Department of Gastroenterology and Moores Cancer Center, University of California San Diego, La Jolla, California
| | - C. RICHARD BOLAND
- Division of Gastroenterology, Department of Internal Medicine, Baylor University Medical Center, Dallas, Texas
| | - AJAY GOEL
- Division of Gastroenterology, Department of Internal Medicine, Baylor University Medical Center, Dallas, Texas
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Bernet A, Mazelin L, Coissieux MM, Gadot N, Ackerman SL, Scoazec JY, Mehlen P. Inactivation of the UNC5C Netrin-1 receptor is associated with tumor progression in colorectal malignancies. Gastroenterology 2007; 133:1840-8. [PMID: 17967459 PMCID: PMC2211510 DOI: 10.1053/j.gastro.2007.08.009] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2007] [Accepted: 07/19/2007] [Indexed: 12/28/2022]
Abstract
BACKGROUND & AIMS The UNC5H netrin-1 receptors (UNC5H1-3 also called UNC5A-C) belong to the functional dependence receptors family, which share the ability to induce apoptosis in the absence of their ligands. Such a trait has been hypothesized to confer a tumor-suppressor activity. Indeed, cells harboring these receptors are thought to be dependent on ligand availability for their survival, thereby inhibiting uncontrolled tumor cell proliferation. We investigate here whether UNC5C acts as a tumor suppressor in colorectal malignancies. METHODS The level of UNC5C was analyzed in a panel of 86 primary sporadic colorectal carcinomas. Loss of heterozygosity in the UNC5C locus and epigenetic alterations in the UNC5C promoter were also analyzed. Intestinal tumor progression was monitored in mice bearing both UNC5C and APC1638N mutations, and apoptosis was measured in intestinal tumors developed in UNC5C/APC1638N mutant mice. RESULTS We show here that UNC5C expression is down-regulated in a large fraction of human colorectal cancers, mainly through promoter methylation. Moreover, in mice, inactivation of UNC5C is associated with increased intestinal tumor progression and a decrease in tumor cell apoptosis. CONCLUSIONS The loss of UNC5C expression observed in human colorectal cancer is a selective advantage for tumor progression, in agreement with the dependence receptor hypothesis. Thus, the UNC5C dependence receptor is a tumor suppressor that regulates sporadic colorectal cancer.
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Affiliation(s)
- Agnès Bernet
- Apoptosis, Cancer and Development Laboratory- Equipe labellisée ‘La Ligue’, CNRS UMR5238, University of Lyon, Centre Léon Bérard, 69008 Lyon, France
| | - Laetitia Mazelin
- Apoptosis, Cancer and Development Laboratory- Equipe labellisée ‘La Ligue’, CNRS UMR5238, University of Lyon, Centre Léon Bérard, 69008 Lyon, France
| | - Marie-May Coissieux
- Apoptosis, Cancer and Development Laboratory- Equipe labellisée ‘La Ligue’, CNRS UMR5238, University of Lyon, Centre Léon Bérard, 69008 Lyon, France
| | - Nicolas Gadot
- ANIPATH, Génopole Rhône–Alpes/Université Lyon 1, Faculté Laennec, 69372, Lyon, France
| | - Susan L. Ackerman
- The Jackson Laboratory, 600 Main Street, Bar Harbor, Maine, 04609, USA
| | - Jean-Yves Scoazec
- ANIPATH, Génopole Rhône–Alpes/Université Lyon 1, Faculté Laennec, 69372, Lyon, France,INSERM, U45, IFR62, University of Lyon, 69372 Lyon, France
| | - Patrick Mehlen
- Apoptosis, Cancer and Development Laboratory- Equipe labellisée ‘La Ligue’, CNRS UMR5238, University of Lyon, Centre Léon Bérard, 69008 Lyon, France,The Buck Institute for Age Research, Novato, CA, USA
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70
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Carvalho AL, Chuang A, Jiang WW, Lee J, Begum S, Poeta L, Zhao M, Jerónimo C, Henrique R, Nayak CS, Park HL, Brait MRO, Liu C, Zhou S, Koch W, Fazio VM, Ratovitski E, Trink B, Westra W, Sidransky D, Moon CS, Califano JA. Deleted in colorectal cancer is a putative conditional tumor-suppressor gene inactivated by promoter hypermethylation in head and neck squamous cell carcinoma. Cancer Res 2007; 66:9401-7. [PMID: 17018594 DOI: 10.1158/0008-5472.can-06-1073] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Deleted in colorectal cancer (DCC) is a candidate tumor-suppressor gene located at chromosome 18q21. However, DCC gene was found to have few somatic mutations and the heterozygous mice (DCC(+/-)) showed a similar frequency of tumor formation compared with the wild-type mice (DCC(+/+)). Recently, DCC came back to the spotlight as a better understating of its function and relationship with its ligand (netrin-1) had shown that DCC may act as a conditional tumor-suppressor gene. We evaluated hypermethylation as a mechanism for DCC inactivation in head and neck squamous cell carcinoma (HNSCC). DCC promoter region hypermethylation was found in 75% of primary HNSCC. There was a significant correlation between DCC promoter region hypermethylation and DCC expression (assessed by immunohistochemistry; P = 0.021). DCC nonexpressing HNSCC cell lines JHU-O12 and JHU-O19 with baseline hypermethylation of the DCC promoter were treated with 5-aza-2'-deoxycytidine (a demethylating agent) and reexpression of DCC was noted. Transfection of DCC into DCC-negative HNSCC cell lines resulted in complete abrogation of growth in all cell lines, whereas additional cotransfection of netrin-1 resulted in rescue of DCC-mediated growth inhibition. These results suggest that DCC is a putative conditional tumor-suppressor gene that is epigenetically inactivated by promoter hypermethylation in a majority of HNSCC.
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MESH Headings
- Carcinoma, Squamous Cell/genetics
- Carcinoma, Squamous Cell/pathology
- Cell Line, Tumor
- CpG Islands/genetics
- DCC Receptor
- DNA Methylation
- DNA, Neoplasm/chemistry
- DNA, Neoplasm/genetics
- Gene Expression Regulation, Neoplastic
- Genes, DCC
- Head and Neck Neoplasms/genetics
- Head and Neck Neoplasms/pathology
- Humans
- Loss of Heterozygosity
- Neoplasm Proteins/biosynthesis
- Neoplasm Proteins/deficiency
- Neoplasm Proteins/genetics
- Neoplasm Proteins/physiology
- Nerve Growth Factors/genetics
- Nerve Growth Factors/physiology
- Netrin-1
- Promoter Regions, Genetic/genetics
- Receptors, Cell Surface/biosynthesis
- Receptors, Cell Surface/deficiency
- Receptors, Cell Surface/physiology
- Transfection
- Tumor Suppressor Proteins/biosynthesis
- Tumor Suppressor Proteins/deficiency
- Tumor Suppressor Proteins/genetics
- Tumor Suppressor Proteins/physiology
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Affiliation(s)
- André Lopes Carvalho
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins Medical Institutions, Baltimore, MD 21287-0910, USA
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71
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Mueller BK, Yamashita T, Schaffar G, Mueller R. The role of repulsive guidance molecules in the embryonic and adult vertebrate central nervous system. Philos Trans R Soc Lond B Biol Sci 2007; 361:1513-29. [PMID: 16939972 PMCID: PMC1664662 DOI: 10.1098/rstb.2006.1888] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
During the development of the nervous system, outgrowing axons often have to travel long distances to reach their target neurons. In this process, outgrowing neurites tipped with motile growth cones rely on guidance cues present in their local environment. These cues are detected by specific receptors expressed on growth cones and neurites and influence the trajectory of the growing fibres. Neurite growth, guidance, target innervation and synapse formation and maturation are the processes that occur predominantly but not exclusively during embryonic or early post-natal development in vertebrates. As a result, a functional neural network is established, which is usually remarkably stable. However, the stability of the neural network in higher vertebrates comes at an expensive price, i.e. the loss of any significant ability to regenerate injured or damaged neuronal connections in their central nervous system (CNS). Most importantly, neurite growth inhibitors prevent any regenerative growth of injured nerve fibres. Some of these inhibitors are associated with CNS myelin, others are found at the lesion site and in the scar tissue. Traumatic injuries in brain and spinal cord of mammals induce upregulation of embryonic inhibitory or repulsive guidance cues and their receptors on the neurites. An example for embryonic repulsive directional cues re-expressed at lesion sites in both the rat and human CNS is provided with repulsive guidance molecules, a new family of directional guidance cues.
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Affiliation(s)
- Bernhard K Mueller
- Neuroscience Discovery Research, Abbott GmbH & Co. KG, Knollstrasse 50, 67061 Ludwigshafen, Germany.
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72
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Yamashita T, Mueller BK, Hata K. Neogenin and repulsive guidance molecule signaling in the central nervous system. Curr Opin Neurobiol 2007; 17:29-34. [PMID: 17169551 DOI: 10.1016/j.conb.2006.12.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2006] [Accepted: 12/05/2006] [Indexed: 12/15/2022]
Abstract
The repulsive guidance molecule (RGM) is a membrane-bound protein that was originally identified as an axon guidance molecule in the visual system. Functional studies have revealed that it has roles in axon guidance and laminar patterning in Xenopus and chick embryos, and in controlling cephalic neural tube closure in mouse embryos. The recent identification of neogenin as a receptor for RGM has provided evidence of the diverse functions of this ligand-receptor pair. Re-expression of RGM is observed after injury in the adult human and rat central nervous systems. Inhibition of RGM enhances growth of injured axons and promotes functional recovery after spinal cord injury in rats. Thus, re-expression of embryonic repulsive cues in adult tissues contributes to failure of axon regeneration in the central nervous system.
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Affiliation(s)
- Toshihide Yamashita
- Department of Neurobiology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chiba 260-8670, Japan.
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73
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Li W, Aurandt J, Jürgense C, Rao Y, Guan KL. FAK and Src kinases are required for netrin-induced tyrosine phosphorylation of UNC5. J Cell Sci 2006; 119:47-55. [PMID: 16371650 PMCID: PMC2248276 DOI: 10.1242/jcs.02697] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
During neuronal development, netrin and its receptors UNC5 and DCC (deleted in colorectal cancer) guide axonal growth cones in navigating to their targets. Netrin also plays important roles in the regulation of cell migration, tissue morphogenesis and tumor growth. Here, we show that netrin induces UNC5 tyrosine phosphorylation and that this effect of netrin is dependent on its co-receptor DCC. UNC5 tyrosine phosphorylation is known to be important for netrin to induce cell migration and axonal repulsion. Src tyrosine kinase activity is required for netrin to stimulate UNC5 tyrosine phosphorylation in neurons and transfected cells. The SH2 domain of Src kinase directly interacts with the cytosolic domain of UNC5 in a tyrosine-phosphorylation-dependent manner. Furthermore, the tyrosine kinase focal adhesion kinase (FAK) is also involved in netrin-induced UNC5 tyrosine phosphorylation. Both Src and FAK can phosphorylate UNC5. Our data suggest a model in which netrin stimulates UNC5 tyrosine phosphorylation and signaling in a manner dependent on the co-receptor DCC, through the recruitment of Src and FAK kinases.
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Affiliation(s)
- Weiquan Li
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
- *Authors for correspondence (e-mail: ; )
| | - Jennifer Aurandt
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Claudia Jürgense
- Department of Neurobiology, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Yi Rao
- Department of Neurobiology, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Kun-Liang Guan
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
- Institute of Gerontology, University of Michigan, Ann Arbor, MI 48109, USA
- *Authors for correspondence (e-mail: ; )
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74
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Affiliation(s)
- Dan J Raz
- Department of Surgery, Division of Cardiothoracic Surgery, University of California, San Francisco, 94143-1724, USA
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75
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Abstract
The metastatic process is highly inefficient--very few of the many cells that migrate from the primary tumour successfully colonize distant sites. One proposed mechanism to explain this inefficiency is provided by the cancer stem cell model, which hypothesizes that micrometastases can only be established by tumour stem cells, which are few in number. However, recent in vitro and in vivo observations indicate that apoptosis is an important process regulating metastasis. Here we stress that the inhibition of cell death, apart from its extensively described function in primary tumour development, is a crucial characteristic of metastatic cancer cells.
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Affiliation(s)
- Patrick Mehlen
- Apoptosis, Cancer and Development Laboratory-Equipe labellisée La Ligue, CNRS FRE2870, Centre Léon Bérard, Université Claude Bernard Lyon 1, 69008 Lyon, France.
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76
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Furne C, Corset V, Hérincs Z, Cahuzac N, Hueber AO, Mehlen P. The dependence receptor DCC requires lipid raft localization for cell death signaling. Proc Natl Acad Sci U S A 2006; 103:4128-33. [PMID: 16537496 PMCID: PMC1449658 DOI: 10.1073/pnas.0507864103] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
DCC (deleted in colorectal cancer) is a putative tumor suppressor gene whose expression is lost in numerous cancers. DCC also encodes the main receptor for the neuronal navigation cue netrin-1. It has been shown that DCC belongs to the so-called family of dependence receptors. Such receptors induce apoptosis when their ligand is absent, thus conferring a state of cellular dependence on ligand availability. We recently proposed that DCC is a tumor suppressor because it induces the death of tumor cells that grow in settings of ligand unavailability. Moreover, it seems that the DCC/netrin-1 pair may also regulate neuron survival during nervous system development. However, the mechanisms by which DCC triggers cell death are still unknown. We show here that the localization of DCC to lipid rafts is a prerequisite for its proapoptotic activity, both in immortalized cells and in primary neurons. The presence of DCC in lipid rafts probably allows the formation of an adequate submembrane complex, because the interaction of caspase-9 with DCC is inhibited by the disorganization of lipid rafts. Thus, dependence receptors may require lipid raft localization for cell death signaling.
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Affiliation(s)
- Céline Furne
- Apoptosis, Cancer, and Development Laboratory, Equipe la Ligue, Centre National de la Recherche Scientifique Formation de Recherche en Evolution 2870 (CNRS FRE 2870), Centre Léon Berard, 69008 Lyon, France
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77
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Abstract
Cells depend for their survival on stimulation by trophic factors and other prosurvival signals, the withdrawal of which induces apoptosis, both via the loss of antiapoptotic signaling and the activation of proapoptotic signaling via specific receptors. These receptors, dubbed dependence receptors, activate apoptotic pathways following the withdrawal of trophic factors and other supportive stimuli. Such receptors may feature in developmental cell death, carcinogenesis (including metastasis), neurodegeneration, and possibly subapoptotic events such as neurite retraction and somal atrophy. Mechanistic studies of dependence receptors suggest that these receptors form ligand-dependent complexes that include specific caspases. Complex formation in the absence of ligand leads to caspase activation by a mechanism that is typically dependent on caspase cleavage of the receptor itself, releasing proapoptotic peptides. Cellular dependence receptors, considered in the aggregate, may thus form a system of molecular integration, analogous to the electrical integration system provided by dendritic arbors in the nervous system.
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Affiliation(s)
- D E Bredesen
- The Buck Institute for Age Research, Novato, CA 94945, USA.
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78
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Hérincs Z, Corset V, Cahuzac N, Furne C, Castellani V, Hueber AO, Mehlen P. DCC association with lipid rafts is required for netrin-1-mediated axon guidance. J Cell Sci 2005; 118:1687-92. [PMID: 15811950 DOI: 10.1242/jcs.02296] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
During development, axons migrate long distances in responses to attractive or repulsive signals that are detected by their growth cones. One of these signals is mediated by netrin-1, a diffusible laminin-related molecule that both attracts and repels growth cones via interaction with its receptor DCC (deleted in colorectal cancer). Here we show that DCC in both commissural neurons and immortalized cells, is partially associated with cholesterol- and sphingolipid-enriched membrane domains named lipid rafts. This localization of DCC in lipid rafts is mediated by the palmitoylation within its transmembrane region. Moreover, this raft localization of DCC is required for netrin-1-induced DCC-dependent ERK activation, and netrin-1-mediated axon outgrowth requires lipid raft integrity. Thus, the presence of axon guidance-related receptors in lipid rafts appears to be a crucial pre-requisite for growth cone response to chemo-attractive or repulsive cues.
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Affiliation(s)
- Zoltán Hérincs
- Death Receptor Signalling Laboratory -- Equipe ATIP CNRS, Institute of Signalling, Developmental Biology and Cancer Research, CNRS UMR 6543 Centre A. Lacassagne 33 Avenue Valombrose 06189 Nice, France
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79
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Abstract
Although cancer is a multifaceted disease, all cancer types share identical molecular and cellular mechanisms. These mechanisms involve a collection of alterations critical to the normal physiological functioning of cells, such as alterations of growth factor signalling pathways, angiogenesis, cell adhesion signals, DNA replication and apoptotic cell death. Many genes involved in the processes enumerated above are functionally inactive in tumour cells, designating them as putative ‘tumour suppressor genes’. Back in the early 1990s, Vogelstein and colleagues suggested that a gene called DCC (for Deleted in Colorectal Cancer) could be a tumour suppressor gene because it was found to be deleted in more than 70% of colorectal cancers, as well as in many other cancers. During the last 15 years, controversial data have failed to firmly establish whether DCC is indeed a tumour suppressor gene. However, the recent observations that DCC triggers cell death and is a receptor for netrin-1, a molecule recently implicated in colorectal tumorigenesis, have prompted a renewal of interest in the role of DCC in tumorigenesis and suggest that the netrin-1/receptor pairs act as novel negative regulators of tumour development.
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Affiliation(s)
- P Mehlen
- 1Apoptosis, Cancer and Development Laboratory, Laboratoire labellisé 'La Ligue', CNRS FRE2870, Centre Léon Bérard, 28 rue Laennec, 69008 Lyon, France.
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80
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Kim JC, Roh SA, Lee KH, Namgung H, Kim JR, Kim JS. Genetic and Pathologic Changes associated with Lymphovascular Invasion of Colorectal Adenocarcinoma. Clin Exp Metastasis 2005; 22:421-8. [PMID: 16283485 DOI: 10.1007/s10585-005-1550-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2005] [Accepted: 08/02/2005] [Indexed: 11/25/2022]
Abstract
Lymphovascular invasion (LVI) is a biological manifestation of aggressive behavior in colorectal cancer. This study sought to identify and examine the association between genetic and pathologic alterations implicated in this invasive tumor progression. We consecutively recruited 81 and 79 colorectal cancer patients with and without LVI, respectively. Biological changes were evaluated by clinicopathological parameters together with CEA and E-cadherin expressions using immune staining. Allelic loss or MSI was examined using 10 microsatellite markers on chromosomes 10, 16, 18, and TGFbetaRII, possibly associated with colorectal cancer. The germline mutation of BMPR1A and SMAD4 was also sought. Tumor stage and lymph node metastasis were significantly greater in patients with LVI tumor than without it (P < 0.001). Decreased CEA expression was closely correlated with allelic loss or MSI at D16S421, D18S46, and D18S474 (P = 0.004-0.047). Allelic loss at D10S14 was specific to LVI tumors (P = 0.007). Using multivariate analysis, allelic loss at D18S46 significantly correlated with histological differentiation (P = 0.02). In addition, allelic loss and MSI at D18S474, histological differentiation, and expression of CEA and E-cadherin were closely associated with the progression of LVI (P = 0.005-0.049). However, no germline mutation in BMPR1A or SMAD4 was detected in all patients regardless of LVI status. In summary, in a subset of colorectal cancers, histological differentiation and expression of CEA or E-cadherin appear to determine aggressive behavior such as LVI. These changes are closely associated with chromosomal alterations at 10q22-23, 16q22 and 18q21, which carry several tumor suppressor genes.
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Affiliation(s)
- Jin C Kim
- Department of Surgery, University of Ulsan College of Medicine and Asan Medical Center, 388-1, Poongnap-2-Dong Songpa-Ku, Seoul, 138-736, Korea.
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81
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Bernet A, Mehlen P. [Netrin-1 and its dependence receptors: role in colorectal cancers]. ACTA ACUST UNITED AC 2005; 53:328-33. [PMID: 16004944 DOI: 10.1016/j.patbio.2004.10.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2004] [Accepted: 10/19/2004] [Indexed: 10/26/2022]
Abstract
Currently, an increasing number of receptors appear to belong to the dependence receptors family. These proteins have the capacity to induce a program of apoptosis in settings of absence of their ligand. A cell that expresses one of these receptors is thus dependent on the presence of the ligand to survive. The observation that these receptors are lost in many cancers is then suggesting that this loss is a selective advantage for tumor development because it leads tumor cells not to be dependent for survival on the presence of the ligand. We propose to focus this review on the role of some of these receptors that have been intensively studied: the dependence receptors that bind the netrin-1. After having pointed out their role in the development of the nervous system and in cell death induction, we will discuss their putative role in the pathological context of tumorigenesis and more particularly in the control of colorectal cancers.
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Affiliation(s)
- A Bernet
- Apoptose, cancer et développement, laboratoire labellisé La Ligue, FRE CNRS, centre Léon-Berard, 28, rue Laennec, 69008 Lyon, France.
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82
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Gaillard S, Nasarre C, Gonthier B, Bagnard D. Mécanismes cellulaires et moléculaires de la croissance axonale. Rev Neurol (Paris) 2005; 161:153-72. [PMID: 15798515 DOI: 10.1016/s0035-3787(05)85019-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION During embryonic and post-natal development, numerous axonal connections are formed establishing a functional nervous system. Knowledge of the underlying molecular and cellular mechanisms controlling this phenomenon is improving. STATE OF THE ART In this review, we present the general principles of axon guidance together with the major families of guidance signals. This includes the tyrosine kinase receptors Eph and their ligands Ephrins, the netrins, the semaphorins, the slits and other major components of the extracellular matrix. These types of guidance signals share common functional properties leading to actin cytoskeleton remodelling. The direct or indirect interactions between the receptors of these guidance cues and actin modulators is the final step of the signalling cascade constituting the fundamental mechanism defining the orientation and extension of the axonal growth cone. These factors are involved in the formation of many, if not all, axonal projections for which they act as repulsive (inhibitory) or attractive (promoting) signals. PERSPECTIVES the knowledge of these mechanisms is particularly interesting since the inhibition of axonal outgrowth is considered to be one of the major obstacles to nerve regeneration in the central nervous system. Indeed, most of the guidance signals expressed during brain development are up-regulated in lesion sites where they contribute to the lack of nerve re-growth. Here, we present the nature of the mechanical barrier, the so called glial scar, and we describe the major inhibitory molecules preventing axonal extension. CONCLUSION the comprehension of the molecular mechanisms involved in axon growth and guidance represents a major advance towards the definition of novel therapeutic strategies improving nerve regeneration. The path to the clinical application of these molecular factors remains long. Nevertheless, the next decade will undoubtedly provide challenging data that will modify the current therapeutic approaches.
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Affiliation(s)
- S Gaillard
- INSERM U575, Physiopathologie du Système Nerveux, Groupe de Physiologie Moléculaire de la Régénération Nerveuse, 67084 Strasbourg
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83
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Yan W, Song L, Liang Q, Fang Y. Progression Analysis of Lung Squamous Cell Carcinomas by Comparative Genomic Hybridization. Tumour Biol 2005; 26:158-64. [PMID: 15970651 DOI: 10.1159/000086488] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2004] [Accepted: 01/25/2005] [Indexed: 12/31/2022] Open
Abstract
OBJECTIVE The genetic mechanisms underlying the development and progression of lung squamous cell carcinoma (SCC), the major subtype of non-small cell lung cancer, are still unknown. To better understand this disease, we studied the association between genetic alterations and the progression of lung SCC. METHODS Chromosomal aberrations in 39 samples of lung SCC, including 21 nonmetastatic and 18 metastatic carcinomas, were characterized by comparative genomic hybridization and statistically correlated to clinical staging and metastatic ability. RESULTS The average gains and losses per patient were significantly higher in the advanced-stage lung SCC and metastatic SCC group compared to the early-stage lung SCC and nonmetastatic SCC group. Gains of 2p, 20p and losses of 2q, 4q, 5q, 9q, 13p, 18q correlated with advanced-stage lung SCC. Losses on 2q, 4q, 6p, 16p, 16q, 18q, 20q, 21q and gains on 2p, 7p, 7q, 20p were more frequent in the metastatic SCC group, which was significantly different from the nonmetastatic SCC group. Gains on 2p, 20p and losses on 2q, 4q, 18q were not only associated with an advanced clinical stage but also with metastases of lung SCC. CONCLUSIONS The results suggest that several chromosomal aberrations (e.g. gains on 2p, 20p and losses on 2q, 4q, 18q) may contribute to the progression of lung SCC.
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Affiliation(s)
- Wensheng Yan
- Cancer Institute of Cancer Center, Sun Yat-Sen University, Guangzhou, China
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84
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Wettergren Y, Odin E, Nilsson S, Willen R, Carlsson G, Gustavsson B. Low expression of reduced folate carrier-1 and folylpolyglutamate synthase correlates with lack of a deleted in colorectal carcinoma mRNA splice variant in normal-appearing mucosa of colorectal carcinoma patients. ACTA ACUST UNITED AC 2005; 29:348-55. [PMID: 16122883 DOI: 10.1016/j.cdp.2005.06.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2005] [Indexed: 11/19/2022]
Abstract
BACKGROUND Cellular folate deficiency leads to DNA strand breaks, mutations, and aberrant methylation and might be a risk factor for colorectal cancer (CRC). The putative tumor suppressor gene deleted in colorectal carcinoma (DCC) is one of several genes the expression of which seems to be affected by the folate concentration at the tissue level. Decreased expression of DCC may be caused by LOH or hypermethylation, i.e. by events that might be linked to folate deficiency. The purpose of this study was to analyze if the folate level and the gene expression levels of reduced folate carrier (RFC-1) and folylpolyglutamate synthase (FPGS) had impact on the expression of DCC splice variants. METHODS Quantification of RFC-1 and FPGS expression in mucosa of 53 CRC patients was performed using real-time PCR whereas DCC splicing variants were detected by automated capillary gel electrophoresis. Total reduced folate concentration was measured with the FdUMP-binding assay (n = 22). RESULTS Significantly higher expression levels of RFC-1 (p = 0.026) and FPGS (p = 0.05) were found in mucosa expressing the splice variant DCC342 compared to mucosa that did not. Furthermore, multivariate analysis showed that RFC-1 and FPGS (r = 0.49, p = 0.01) as well as folate and RFC-1 (r = 0.56, p = 0.023) were correlated only in mucosa expressing DCC342. CONCLUSIONS In conclusion, the present study points to a potential influence of folates in regulating DCC expression at multiple levels involving post-transcriptional pathways. The results may provide a basis for a detailed investigation of molecular mechanisms involved in folate regulation of DCC expression.
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Affiliation(s)
- Yvonne Wettergren
- Department of General Surgery, Sahlgrenska University Hospital/Ostra, Goteborg University, S-416 85 Goteborg, Sweden.
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85
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Mehlen P, Thibert C. Dependence receptors: between life and death. Cell Mol Life Sci 2004; 61:1854-66. [PMID: 15289929 PMCID: PMC11138646 DOI: 10.1007/s00018-004-3467-7] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2003] [Revised: 02/19/2004] [Accepted: 02/26/2004] [Indexed: 11/27/2022]
Abstract
The recently described family of dependence receptors is a new family of functionally related receptors. These proteins have little sequence similarity but display the common feature of inducing two completely opposite intracellular signals depending on ligand availability: in the presence of ligand, these receptors transduce a positive signal leading to survival, differentiation or migration, while in the absence of ligand, the receptors initiate or amplify a negative signal for apoptosis. Thus, cells that express these proteins manifest a state of dependence on their respective ligands. The mechanisms that trigger cell death induction in the absence of ligand are in large part unknown, but typically require cleavage by specific caspases. In this review we will present the proposed mechanisms for cell death induction by these receptors and their potential function in nervous system development and regulation of tumorigenesis.
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Affiliation(s)
- P Mehlen
- Apoptosis/Differentiation Laboratory, Equipe labelisée La Ligue, Molecular and Cellular Genetic Center, CNRS UMR 5534, University of Lyon, 69622, Villeurbanne, France.
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