The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Tomonori Aoyama - One of the best experts on this subject based on the ideXlab platform.

  • nicotinamide adenine dinucleotide phosphate oxidase in experimental liver fibrosis gkt137831 as a novel potential therapeutic agent
    Hepatology, 2012
    Co-Authors: Tomonori Aoyama, Yonghan Paik, Sumio Watanabe, Benoit Laleu, Francesca Gaggini, Laetitia Fiorasocartier, Sophie Molango, Freddy Heitz, Cedric Merlot
    Abstract:

    Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) generates reactive oxygen species (ROS) in hepatic stellate cells (HSCs) during liver fibrosis. In response to fibrogenic agonists, such as angiotensin II (Ang II), the NOX1 components form an active complex, including Ras-related botulinum toxin substrate 1 (Rac1). Superoxide dismutase 1 (SOD1) interacts with the NOX-Rac1 complex to stimulate NOX activity. NOX4 is also induced in activated HSCs/myofibroblast by increased gene expression. Here, we investigate the role of an enhanced activity SOD1 G37R mutation (SODmu) and the effects of GKT137831, a dual NOX1/4 inhibitor, on HSCs and liver fibrosis. To induce liver fibrosis, wild-type (WT) and SOD1mu mice were treated with CCl4 or bile duct ligation (BDL). Then, to address the role of NOX-SOD1-mediated ROS production in HSC activation and liver fibrosis, mice were treated with a NOX1/4 inhibitor. Fibrosis and ROS generation was assessed by histology and measurement of thiobarbituric acid reactive substances and NOX-related genes. Primary cultured HSCs isolated from WT, SODmu, and NOX1 knockout (KO) mice were assessed for ROS production, Rac1 activity, and NOX gene expression. Liver fibrosis was increased in SOD1mu mice, and ROS production and Rac1 activity were increased in SOD1mu HSCs. The NOX1/4 inhibitor, GKT137831, attenuated liver fibrosis and ROS production in both SOD1mu and WT mice as well as messenger RNA expression of fibrotic and NOX genes. Treatment with GKT137831 suppressed ROS production and NOX and fibrotic gene expression, but not Rac1 activity, in SOD1mut and WT HSCs. Both Ang II and tumor growth factor beta up-regulated NOX4, but Ang II required NOX1. Conclusions: SOD1mu induces excessive NOX1 activation through Rac1 in HSCs, causing enhanced NOX4 up-regulation, ROS generation, and liver fibrosis. Treatment targeting NOX1/4 may be a new therapy for liver fibrosis. (HEPATOLOGY 2012)

  • nicotinamide adenine dinucleotide phosphate oxidase in experimental liver fibrosis gkt137831 as a novel potential therapeutic agent
    Hepatology, 2012
    Co-Authors: Tomonori Aoyama, Yonghan Paik, Sumio Watanabe, Benoit Laleu, Francesca Gaggini, Laetitia Fiorasocartier, Sophie Molango, Freddy Heitz, Cedric Merlot
    Abstract:

    Background & Aims NADPH oxidase (NOX) generates reactive oxygen species (ROS) in hepatic stellate cells (HSCs) during liver fibrosis. In response to fibrogenic agonists, such as angiotensin II (Ang II), the NOX1 components form an active complex including Rac1. Superoxide dismutase 1 (SOD1) interacts with the NOX-Rac1 complex to stimulate NOX activity. NOX4 is also induced in activated HSCs/myofibroblast by increased gene expression. Here, we investigate the role of an enhanced activity SOD1 G37R mutation (SODmu) and the effects of GKT137831, a dual NOX1/4 inhibitor, on HSCs and liver fibrosis.

Cedric Merlot - One of the best experts on this subject based on the ideXlab platform.

  • nicotinamide adenine dinucleotide phosphate oxidase in experimental liver fibrosis gkt137831 as a novel potential therapeutic agent
    Hepatology, 2012
    Co-Authors: Tomonori Aoyama, Yonghan Paik, Sumio Watanabe, Benoit Laleu, Francesca Gaggini, Laetitia Fiorasocartier, Sophie Molango, Freddy Heitz, Cedric Merlot
    Abstract:

    Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) generates reactive oxygen species (ROS) in hepatic stellate cells (HSCs) during liver fibrosis. In response to fibrogenic agonists, such as angiotensin II (Ang II), the NOX1 components form an active complex, including Ras-related botulinum toxin substrate 1 (Rac1). Superoxide dismutase 1 (SOD1) interacts with the NOX-Rac1 complex to stimulate NOX activity. NOX4 is also induced in activated HSCs/myofibroblast by increased gene expression. Here, we investigate the role of an enhanced activity SOD1 G37R mutation (SODmu) and the effects of GKT137831, a dual NOX1/4 inhibitor, on HSCs and liver fibrosis. To induce liver fibrosis, wild-type (WT) and SOD1mu mice were treated with CCl4 or bile duct ligation (BDL). Then, to address the role of NOX-SOD1-mediated ROS production in HSC activation and liver fibrosis, mice were treated with a NOX1/4 inhibitor. Fibrosis and ROS generation was assessed by histology and measurement of thiobarbituric acid reactive substances and NOX-related genes. Primary cultured HSCs isolated from WT, SODmu, and NOX1 knockout (KO) mice were assessed for ROS production, Rac1 activity, and NOX gene expression. Liver fibrosis was increased in SOD1mu mice, and ROS production and Rac1 activity were increased in SOD1mu HSCs. The NOX1/4 inhibitor, GKT137831, attenuated liver fibrosis and ROS production in both SOD1mu and WT mice as well as messenger RNA expression of fibrotic and NOX genes. Treatment with GKT137831 suppressed ROS production and NOX and fibrotic gene expression, but not Rac1 activity, in SOD1mut and WT HSCs. Both Ang II and tumor growth factor beta up-regulated NOX4, but Ang II required NOX1. Conclusions: SOD1mu induces excessive NOX1 activation through Rac1 in HSCs, causing enhanced NOX4 up-regulation, ROS generation, and liver fibrosis. Treatment targeting NOX1/4 may be a new therapy for liver fibrosis. (HEPATOLOGY 2012)

  • nicotinamide adenine dinucleotide phosphate oxidase in experimental liver fibrosis gkt137831 as a novel potential therapeutic agent
    Hepatology, 2012
    Co-Authors: Tomonori Aoyama, Yonghan Paik, Sumio Watanabe, Benoit Laleu, Francesca Gaggini, Laetitia Fiorasocartier, Sophie Molango, Freddy Heitz, Cedric Merlot
    Abstract:

    Background & Aims NADPH oxidase (NOX) generates reactive oxygen species (ROS) in hepatic stellate cells (HSCs) during liver fibrosis. In response to fibrogenic agonists, such as angiotensin II (Ang II), the NOX1 components form an active complex including Rac1. Superoxide dismutase 1 (SOD1) interacts with the NOX-Rac1 complex to stimulate NOX activity. NOX4 is also induced in activated HSCs/myofibroblast by increased gene expression. Here, we investigate the role of an enhanced activity SOD1 G37R mutation (SODmu) and the effects of GKT137831, a dual NOX1/4 inhibitor, on HSCs and liver fibrosis.

Veronique Lefebvre - One of the best experts on this subject based on the ideXlab platform.

  • SOX11 and sox4 drive the reactivation of an embryonic gene program during murine wound repair
    Nature Communications, 2019
    Co-Authors: Veronique Lefebvre, Elisabeth Sock, Qi Miao, Matthew C Hill, Fengju Chen, Carlos A Ramos, Hoang Nguyen
    Abstract:

    Tissue injury induces changes in cellular identity, but the underlying molecular mechanisms remain obscure. Here, we show that upon damage in a mouse model, epidermal cells at the wound edge convert to an embryonic-like state, altering particularly the cytoskeletal/extracellular matrix (ECM) components and differentiation program. We show that SOX11 and its closest relative SOX4 dictate embryonic epidermal state, regulating genes involved in epidermal development as well as cytoskeletal/ECM organization. Correspondingly, postnatal induction of SOX11 represses epidermal terminal differentiation while deficiency of SOX11 and Sox4 accelerates differentiation and dramatically impairs cell motility and re-epithelialization. Amongst the embryonic genes reactivated at the wound edge, we identify fascin actin-bundling protein 1 (FSCN1) as a critical direct target of SOX11 and SOX4 regulating cell migration. Our study identifies the reactivated embryonic gene program during wound repair and demonstrates that SOX11 and SOX4 play a central role in this process.

  • sequential requirement of sox4 and SOX11 during development of the sympathetic nervous system
    Development, 2010
    Co-Authors: Michaela R Potzner, Veronique Lefebvre, Michael Wegner, Alfredo Penzomendez, Konstantina Tsarovina, Ellen Binder, Hermann Rohrer, Elisabeth Sock
    Abstract:

    The highly related transcription factors Sox4 and SOX11 are expressed in the developing sympathetic nervous system. In the mouse, SOX11 appears first, whereas Sox4 is prevalent later. Using mouse mutagenesis and overexpression strategies in chicken, we studied the role of both SoxC proteins in this tissue. Neither Sox4 nor SOX11 predominantly functioned by promoting pan-neuronal or noradrenergic differentiation of sympathetic neurons as might have been expected from studies in neuronal precursors of the central nervous system. The transcriptional network that regulates the differentiation of sympathetic neurons remained intact and expression of noradrenergic markers showed only minor alterations. Instead, SOX11 was required in early sympathetic ganglia for proliferation of tyrosine hydroxylase-expressing cells, whereas Sox4 ensured the survival of these cells at later stages. In the absence of both Sox4 and SOX11, sympathetic ganglia remained hypoplastic throughout embryogenesis because of consecutive proliferation and survival defects. As a consequence, sympathetic ganglia were rudimentary in the adult and sympathetic innervation of target tissues was impaired leading to severe dysautonomia.

  • the soxd transcription factors sox5 sox6 and SOX13 are key cell fate modulators
    The International Journal of Biochemistry & Cell Biology, 2010
    Co-Authors: Veronique Lefebvre
    Abstract:

    Sox5, Sox6, and SOX13 constitute the group D of sex-determining region (Sry)-related transcription factors. They are highly conserved in the family-specific high-mobility-group (HMG) box DNA-binding domain and in a group-specific coiled-coil domain. The latter mediates SoxD protein dimerization and thereby preferential binding to pairs of DNA recognition sites. The SoxD genes have overlapping expression and cell-autonomously control discrete lineages. Sox5 and Sox6 redundantly enhance chondrogenesis, but retard gliogenesis. Sox5 hinders melanogenesis, promotes neural crest generation, and controls the pace of neurogenesis. Sox6 promotes erythropoiesis, and SOX13 modulates T cell specification and is an autoimmune antigen. SoxD proteins enhance transactivation by Sox9 in chondrocytes, but antagonize Sox9 and other SoxE proteins in oligodendrocytes and melanocytes, and also repress transcription through various mechanisms in several other lineages. While their biological and molecular functions remain incompletely understood, the SoxD proteins have thus already proven that they critically modulate cell fate in major lineages.

  • the three soxc proteins sox4 SOX11 and SOX12 exhibit overlapping expression patterns and molecular properties
    Nucleic Acids Research, 2008
    Co-Authors: Alfredo Penzomendez, Hongzhe Wang, Carlos E Pedraza, Wendy B Macklin, Veronique Lefebvre
    Abstract:

    The group C of Sry-related high-mobility group (HMG) box (Sox) transcription factors has three members in most vertebrates: Sox4, SOX11 and SOX12. Sox4 and SOX11 have key roles in cardiac, neuronal and other major developmental processes, but their molecular roles in many lineages and the roles of SOX12 remain largely unknown. We show here that the three genes are co-expressed at high levels in neuronal and mesenchymal tissues in the developing mouse, and at variable relative levels in many other tissues. The three proteins have conserved remarkable identity through evolution in the HMG box DNA-binding domain and in the C-terminal 33 residues, and we demonstrate that the latter residues constitute their transactivation domain (TAD). SOX11 activates transcription several times more efficiently than Sox4 and up to one order of magnitude more efficiently than SOX12, owing to a more stable α-helical structure of its TAD. This domain and acidic domains interfere with DNA binding, SOX11 being most affected and Sox4 least affected. The proteins are nevertheless capable of competing with one another in reporter gene transactivation. We conclude that the three SoxC proteins have conserved overlapping expression patterns and molecular properties, and might therefore act in concert to fulfill essential roles in vivo.

  • the transcription factors l sox5 and sox6 are essential for cartilage formation
    Developmental Cell, 2001
    Co-Authors: Patrick Smits, Richard R Behringer, Jennifer Mandel, Zhaoping Zhang, Jian Ming Deng, Benoit De Crombrugghe, Ping Li, Veronique Lefebvre
    Abstract:

    Abstract L-Sox5 and Sox6 are highly identical Sry-related transcription factors coexpressed in cartilage. Whereas Sox5 and Sox6 single null mice are born with mild skeletal abnormalities, Sox5; Sox6 double null fetuses die with a severe, generalized chondrodysplasia. In these double mutants, chondroblasts poorly differentiate. They express the genes for all essential cartilage extracellular matrix components at low or undetectable levels and initiate proliferation after a long delay. All cartilages are thus extracellular matrix deficient and remain rudimentary. While chondroblasts in the center of cartilages ultimately activate prehypertrophic chondrocyte markers, epiphyseal chondroblasts ectopically activate hypertrophic chondrocyte markers. Thick intramembranous bone collars develop, but the formation of cartilage growth plates and endochondral bones is disrupted. L-Sox5 and Sox6 are thus redundant, potent enhancers of chondroblast functions, thereby essential for endochondral skeleton formation.

Ya-wen Lin - One of the best experts on this subject based on the ideXlab platform.

  • SOX1 suppresses cell growth and invasion in cervical cancer
    Gynecologic Oncology, 2013
    Co-Authors: Ya-wen Lin, Chunming Tsao, Yulueng Shih, Chiahsin Lin, Mingde Yan
    Abstract:

    Abstract Objective Abnormal activation of the Wnt/β-catenin signaling pathway is common in human cancers, including cervical cancer. Many papers have shown that SRY ( sex-determining region Y )- box ( SOX ) family genes serve as either tumor suppressor genes (TSGs) or oncogenes by regulating the Wnt signaling pathway in different cancers. We have demonstrated recently that epigenetic silencing of SOX1 gene occurs frequently in cervical cancer. However, the possible role of SOX1 in cervical cancer remains unclear. This study aimed to explore whether SOX1 functions as a TSG in cervical cancer. Methods We established a constitutive and an inducible system that overexpressed SOX1 and monitored its function by in vitro experiments. To confirm SOX1 function, we manipulated SOX1 using an inducible expression approach in cell lines. The effect of SOX1 on tumorigenesis was also analyzed in animal models. Results Overexpression of SOX1 inhibited cell proliferation, anchorage independency, and invasion in vitro. SOX1 suppressed tumor growth in nonobese diabetic/severe combined immunodeficiency mice. After induction of SOX1 by doxycycline (DOX), SOX1 inhibited cell growth and invasion in the inducible system. Repression of SOX1 by withdrawal of DOX partially reversed the malignant phenotype in cervical cells. SOX1 inhibited TCF-dependent transcriptional activity and the Wnt target genes. SOX1 also repressed the invasive phenotype by regulating the expression of invasion-related genes. Conclusions Taken together, these data suggest that SOX1 can function as a tumor suppressor partly by interfering with Wnt/β-catenin signaling in cervical cancer.

  • frequent concomitant epigenetic silencing of SOX1 and secreted frizzled related proteins sfrps in human hepatocellular carcinoma
    Journal of Gastroenterology and Hepatology, 2013
    Co-Authors: Yulueng Shih, Chunming Tsao, Mingde Yan, Chungbao Hsieh, Tsaiyuan Hsieh, Changhsin Liu, Ya-wen Lin
    Abstract:

    Background and Aim Except for genetic mutations, epigenetic changes are also involved in the development of human cancers. Recently, we have identified SOX1, SRY (sex determining region Y)-box 1, is hypermethylated in cervical cancer and ovarian cancer. Therefore, we investigated whether promoter hypermethylation of SOX1 is common in hepatocellular carcinoma (HCC). Methods We used methylation-specific polymerase chain reaction (MS-PCR) and bisulfite sequencing to analyze the methyaltion level of the SOX1 promoter in seven HCC cell lines, 54 clinical HCCs, 42 cirrhotic livers, 21 livers with chronic hepatitis, and 15 control livers. Then, we employed quantitative MS-PCR (QMSP) to validate in an independent set of samples (60 paired HCCs and 30 control livers). Finally, we used luciferase reporter and colony formation assay to check the effect of SOX1 in HCC. Results Promoter methylation of SOX1 was significantly frequent in HCC cell lines and clinical HCCs, cirrhotic livers, but not in control livers (P < 0.0001). There is a significant correlation between downregulation of SOX1 expression and promoter methylation. QMSP results confirmed that promoter hypermethylation of SOX1 is significantly more frequent in HCCs than control livers (P < 0.0001). The frequency of SOX1 methylation in patients with secreted frizzled-related proteins (SFRPs) methylation is significantly higher than in patients without SFRPs methylation (P < 0.0001). Furthermore, ectopic expression of SOX1 could suppress T-cell factor-dependent transcriptional activity and colony formation number in HCCs. Conclusions Concomitant epigenetic silencing of SOX1 and SFRPs through promoter hypermethylation is frequent in HCCs, and this might contribute to abnormal activation of canonical Wnt signal pathway.

  • SOX1 functions as a tumor suppressor by antagonizing the wnt β catenin signaling pathway in hepatocellular carcinoma
    Hepatology, 2012
    Co-Authors: Chunming Tsao, Yulueng Shih, Mingde Yan, Chihchi Kuo, Wenchi Lin, Ya-wen Lin
    Abstract:

    Oncogenic activation of the Wnt/β-catenin signaling pathway is common in hepatocellular carcinoma (HCC). Our recent studies have demonstrated that SRY (sex determining region Y)-box 1 (SOX1) and secreted frizzled-related proteins are concomitantly promoter-hypermethylated, and this might lead to abnormal activation of the Wnt signaling pathway in HCC. SOX1 encodes a transcription factor involved in the regulation of embryonic development and cell fate determination. However, the expression and functional role of SOX1 in HCC remains unclear. In this study, we confirmed via quantitative methylation-specific polymerase chain reaction that SOX1 was frequently downregulated through promoter hypermethylation in HCC cells and tissues. Overexpression of SOX1 by a constitutive or inducible approach could suppress cell proliferation, colony formation, and invasion ability in HCC cell lines, as well as tumor growth in nonobese diabetic/severe combined immunodeficiency mice. Conversely, knockdown of SOX1 by withdrawal of doxycycline could partially restore cell proliferation and colony formation in HCC cells. We used a T cell factor (TCF)-responsive luciferase reporter assay and western blot analysis to prove that SOX1 could regulate TCF-responsive transcriptional activity and inhibit the expression of Wnt downstream genes. Furthermore, we used glutathione S-transferase pull-down, co-immunoprecipitation, and confocal microscopy to demonstrate that SOX1 could interact with β-catenin but not with the β-catenin/TCF complex. Moreover, restoration of the expression of SOX1 induces significant cellular senescence in Hep3B cells. Conclusion: Our data show that a developmental gene, SOX1, may function as a tumor suppressor by interfering with Wnt/β-catenin signaling in the development of HCC. (HEPATOLOGY 2012;56:2142–2153)

  • abstract 2199 SOX1 functions as a tumor suppressor through antagonizing wnt β catenin signaling pathway in hepatocellular carcinoma
    Cancer Research, 2011
    Co-Authors: Chunming Tsao, Hung Cheng Lai, Yulueng Shih, Mingde Yan, Chungbao Hsieh, Tsaiyuan Hsieh, Wenchi Lin, Ya-wen Lin
    Abstract:

    Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL Oncogenic activation of the Wnt/β-catenin signaling pathway is common in hepatocellular carcinoma (HCC). Aberrant hypermethylation of tumor suppressor genes in their promoter regions is frequently found in human cancers. Our previous works have demonstrated that SOX1 gene was hypermethylated in HCCs as well as cervical and ovarian cancers. A growing number of papers suggest that SOX family proteins, such as SOX9, SOX17, SOX4 and SOX2, serve as either tumor suppressors or oncoproteins through manipulating Wnt signaling pathway in different types of cancer. However the molecular mechanism is not well understood. In this study, we established an inducible system to overexpress SOX1 in HCC cell lines and checked whether SOX1 have tumor suppressor function in vitro and in vivo. We found that overexpression of SOX1 could inhibit cell proliferation and colony formation in HCC cells and suppress tumor growth in xenograft mice. Next we used GST pull-down, co-immunoprecipitation (co-IP), immunocytochemistry and luciferase reporter assay to study whether SOX1 could interact with β-catenin to regulate Wnt/β-catenin signaling. Our data showed that SOX1 is physically associated with β-catenin/ TCF complex and could inhibit the TCF-dependent transcriptional activity. Furthermore, SOX1 was co-localized with β-catenin in nucleus by confocal microscopy. These results suggest that SOX1 functions as a tumor suppressor through interfering Wnt/β-catenin signaling in HCC. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2199. doi:10.1158/1538-7445.AM2011-2199

  • an epigenetic marker panel for screening and prognostic prediction of ovarian cancer
    International Journal of Cancer, 2009
    Co-Authors: Hung Cheng Lai, Ya-wen Lin, Yuching Chou, Chin Yu Liu
    Abstract:

    Aberrant CpG island hypermethylation is a common finding of cancers, which might be detectable in the tissue or serum of affected patients. We analyzed DNA methylation by methylation-specific polymerase chain reaction of 7 genes, which included secreted frizzled receptor proteins 1, 2, 4, 5 (SFRP1, 2, 4, 5), SRY-box 1 (SOX1), paired box gene 1 (PAX1) and LIM homeobox transcription factor 1, alpha (LMX1A) in primary tumor samples from 126 patients with ovarian cancer, 75 with a benign tumor and 14 with borderline malignancy of an ovarian tumor, and in the serum from 26 patients with ovarian cancer and 20 with a benign tumor. Six of 7 genes had higher methylation rates in patients with ovarian cancer than in borderline malignancy or benign tumor (p < 0.001). The methylation of SFRP1, SFRP2, SOX1 and LMX1A genes correlated with recurrence and overall survival of ovarian cancer patients. Combining the data for SFRP1, SFRP2 and SOX1 genes gave a relative risk for recurrence of 3.19 (p = 0.013) in patients with at least one gene methylation, and combining the data for SFRP1, SOX1 and LMX1A gave an RR for cancer-related death of 6.09 (p = 0.010). Methylation analysis of tissues and serum revealed a significant correlation (kappa values, 0.332–0.598) and a highly sensitivity and specificity rates (73.08 and 75%) as a screening marker. In conclusion, promoter hypermethylation of specific genes in critical pathways is common in ovarian cancer and has potential as a prognostic factor and a promising serum marker for early screening. © 2008 Wiley-Liss, Inc.

Francesc Graus - One of the best experts on this subject based on the ideXlab platform.

  • caveats and pitfalls of SOX1 autoantibody testing with a commercial line blot assay in paraneoplastic neurological investigations
    Frontiers in Immunology, 2019
    Co-Authors: Raquel Ruizgarcia, Eugenia Martinezhernandez, Milagros Garciaormaechea, Marta Espanolrego, Lidia Sabater, Luis Querol, Isabel Illa, Josep Dalmau, Francesc Graus
    Abstract:

    SOX1 autoantibodies are considered markers of small cell lung cancer (SCLC) and paraneoplastic neurological syndromes (PNS) and are usually determined by commercial line blot in many clinical services. Recent studies suggested that SOX1 autoantibodies also occur in patients with neuropathies unrelated to SCLC, questioning the value of SOX1 autoantibodies as paraneoplastic biomarkers. Here, we compared the specificity and sensitivity of a commercial line blot (Euroimmun, Lubeck, Germany) with those of an in house cell-based assay (CBA) with HEK293 cells transfected with SOX1. Overall, 210 patients were included in the study, 139 patients with polyneuropathies without SCLC, and 71 with disorders associated with SOX1 autoantibodies detected with the in-house CBA. Forty one of these 71 cases had been referred to our laboratory for onconeuronal antibody assessment and 30/71 were patients with known PNS and SCLC. None of the patients with polyneuropathies had SOX1 autoantibodies by either line blot or CBA (specificity of the immunoblot: 100%; 95%C.I.: 97.8-100). Among the 71 patients with CBA SOX1 autoantibodies, only 53 were positive by line blot (sensitivity: 74.6%; 95%C.I.: 62.9-84.2). Lung cancer was detected in 37/41 (90%; 34 with SCLC) patients referred for onconeuronal antibody assessment and 34 of them also had a PNS. Our study confirms the association of SOX1 autoantibodies with SCLC and PNS. The line blot test misses 25% of the cases; therefore, to minimize the frequency of false negative results we recommend the use of a confirmatory test, such as CBA, in patients suspected to have a SCLC-related PNS.

  • antibody repertoire in paraneoplastic cerebellar degeneration and small cell lung cancer
    PLOS ONE, 2013
    Co-Authors: Lidia Sabater, Josep Dalmau, Romana Hoftberger, Anna Boronat, Albert Saiz, Francesc Graus
    Abstract:

    The goal of this study is to determine whether patients with paraneoplastic cerebellar degeneration (PCD) and small-cell lung cancer (SCLC) have a specific repertoire of antibodies, if SOX1 antibodies (SOX1-ab) can predict the presence of SCLC, and if antibodies to cell surface antigens occur in this syndrome. Antibody analysis was done using immunohistochemistry on rat brain, immunoblot with recombinant antigens, screening of cDNA expression libraries, and immunolabeling of live neurons in 39 patients with PCD and SCLC. VGCC-ab were measured by RIA, and SOX1-ab, Hu-ab, and ZIC4-ab by immunoblot. Lambert-Eaton myastenic syndrome (LEMS) was present in 10 of 23 patients with electrophysiological studies. At least one antibody was detected in 72% of patients. The individual frequencies were: 49% SOX1-ab, 44% VGCC-ab, 31% Hu-ab, and 13% ZIC4-ab. SOX1-ab occurred in 76% of patients with VGCC-ab and 27% of those without VGCC-ab (p = 0.0036). SOX1-ab were not found in 39 patients with sporadic late-onset cerebellar ataxia, 23 with cerebellar ataxia and glutamic acid decarboxylase antibodies, and 73 with PCD and cancer types other than SCLC (31 without onconeural antibodies, 25 with Yo-ab , 17 with Tr-ab). Five patients (13%) had antibodies against unknown neuronal cell surface antigens but none of them improved with immunotherapy. One serum immunoreacted against the axon initial segment of neurons and another serum against ELKS1, a protein highly expressed in the cerebellum that interacts with the beta4-subunit of the VGCC. In conclusion, 72% of patients with PCD and SCLC had one or more antibodies that indicate the presence of this tumor. In these patients, VGCC-ab and SOX1-ab occur tightly associated. SOX1-ab are predictors of SCLC in ataxia patients with a specificity of 100% and sensitivity of 49%. Unlike limbic encephalitis with SCLC, antibodies to cell surface antigens other than VGCC-ab, are infrequent and do not predict response to treatment.