TY - JOUR A1 - Hailer, Amelie A1 - Grunewald, Thomas G. P. A1 - Orth, Martin A1 - Reiss, Cora A1 - Kneitz, Burkhard A1 - Spahn, Martin A1 - Butt, Elke T1 - Loss of tumor suppressor mir-203 mediates overexpression of LIM and SH3 Protein 1 (LASP1) in high-risk prostate cancer thereby increasing cell proliferation and migration JF - Oncotarget N2 - Several studies have linked overexpression of the LIM and SH3 domain protein 1 (LASP1) to progression of breast, colon, liver, and bladder cancer. However, its expression pattern and role in human prostate cancer (PCa) remained largely undefined. Analysis of published microarray data revealed a significant overexpression of LASP1 in PCa metastases compared to parental primary tumors and normal prostate epithelial cells. Subsequent gene-set enrichment analysis comparing LASP1-high and -low PCa identified an association of LASP1 with genes involved in locomotory behavior and chemokine signaling. These bioinformatic predictions were confirmed in vitro as the inducible short hairpin RNA-mediated LASP1 knockdown impaired migration and proliferation in LNCaP prostate cancer cells. By immunohistochemical staining and semi-quantitative image analysis of whole tissue sections we found an enhanced expression of LASP1 in primary PCa and lymph node metastases over benign prostatic hyperplasia. Strong cytosolic and nuclear LASP1 immunoreactivity correlated with PSA progression. Conversely, qRT-PCR analyses for mir-203, which is a known translational suppressor of LASP1 in matched RNA samples revealed an inverse correlation of LASP1 protein and mir-203 expression. Collectively, our results suggest that loss of mir-203 expression and thus uncontrolled LASP1 overexpression might drive progression of PCa. KW - mir-203 KW - PSA KW - LNCaP KW - LASP1 KW - prostate cancer Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-120540 SN - 1949-2553 VL - 5 IS - 12 ER - TY - THES A1 - Orth, Martin Franz T1 - Generierung und funktionelle Charakterisierung von stabil transfizierten, induzierbar LASP1 spezifische shRNA exprimierenden RT4- und T24-Blasenkarzinomzelllinien T1 - Generation and Functional Characterization of Stably Transduced, Inducible LASP1 Specific shRNA Expressing RT4 and T24 Bladder Cancer Celllines N2 - LASP1 spielt eine Schlüsselrolle in verschiedenen physiologischen und pathologischen Prozessen, wie etwa in der Entwicklung, Zellstruktur, Zellkommunikation, Tumorgenese und Metastasierung. Die Vielseitigkeit von LASP1 ist hauptsächlich durch seine besondere Proteinstruktur bedingt, die eine Interaktion mit vielen verschiedenen Bindepartnern ermöglicht. Effekte von LASP1 werden aber wahrscheinlich nicht nur durch cytosolische Interaktion mit Bindepartnern vermittelt, sondern auch, in Folge einer Translokation in den Zellkern, durch nukleäre Interaktion, evtl. als transkriptioneller Co-Faktor. Besonders die Rolle von LASP1 in diversen Krebserkrankungen stand in den letzten Jahren im Fokus der Forschung. Sowohl in Karzinomen, als auch in Medulloblastom und Leukämien wächst die Evidenz für eine LASP1-Überexpression, die vor allem durch fehlende microRNA Regulation und Mutationen im p53 Tumorsuppressor bedingt scheint. Die hohe LASP1-Expression konnte in vielen in vitro und in vivo Studien mit vermehrter Proliferation, Migration und/ oder Invasion von Krebszelllinien in direkten Zusammenhang gebracht werden. Dieser Effekt von LASP1 auf Tumoraggressivität ist eine mögliche Erklärung für die mit hoher LASP1-Expression korrelierte schlechtere Prognose in verschiedenen Krebserkrankungen. Das Transitionalzellkarzinom ist die fünfhäufigste Krebserkrankung des Menschen und weist eine hohe Rezidivrate auf. Daher sind regelmäßige Nachsorgeuntersuchungen notwendig. Angesichts bisher fehlender verlässlicher Biomarker für das Transitionalzellkarzinom ist die Zystoskopie weiterhin der Goldstandard in der Nachsorge. Diese wird aber von Patienten als unangenehm empfunden, ist mit einem Infektionsrisiko verbunden, von der Erfahrung des Untersuchers abhängig und kostenintensiv. Tatsächlich ist das Transitionalzellkarzinom eine der teuersten Krebserkrankungen in der Nachsorge, weshalb die Entwicklung alternativer Diagnostikverfahren auch gesundheitsökonomische Relevanz hat. LASP1 wurde als ein vielversprechender Biomarker des Transitionalzellkarzinom-Rezidivs identifiziert, der durch einfache Proteinmengenbestimmung mittels Western Blot im Urinpellet evaluiert werden kann. Zum damaligen Zeitpunkt gab es außerdem bereits erste Hinweise auf eine funktionelle Relevanz von LASP1 im Blasenkarzinom in vitro. Angesichts dieser Erkenntnisse wurden als Ziele dieser Arbeit formuliert, 1) die Generierung von stabil transfizierten, induzierbar LASP1 spezifische shRNA exprimierenden Transitionalzellkarzinomzelllinien, 2) die funktionelle Charakterisierung eines LASP1-Knockdowns in selbigen in vitro, und 3) der Vergleich von Eigenschaften von LASP1 im Transitionalzellkarzinom mit denen in anderen Karzinomen. Für die zwei Transitionalzellkarzinomzelllinien T24 und RT4 konnte eine 4-5-Fache LASP1-Überexpression, verglichen mit normalem Urothel, gezeigt werden. Beide Zelllinien wurden erfolgreich mit einem induzierbar shRNA gegen LASP1 exprimierenden Konstrukt transduziert, sodass ein 50 % LASP1-Knockdown durch Doxycyclin induziert werden kann. Bei der Evaluierung des Effektes des LASP1-Knockdowns auf die Adhäsion, Proliferation und Migration dieser Zelllinien in vitro konnte eine signifikante Reduktion der Migration in beiden Zelllinien nachgewiesen werden. Passend dazu ergab eine GSEA von TCGA Daten zum Blasenkarzinom eine Korrelation von LASP1-Expression mit diversen Gen-Sets, die mit dem Phänotyp Metastasierung annotiert sind. Des Weiteren konnte für T24 und RT4 eine nukleäre LASP1-Lokalisation nachgewiesen werden, die abhängig von der Serin-146 Phosphorylierung war. Bioinformatische Analysen ergaben eine hochsignifikante, negative Korrelation von LASP1-Expression und miR-203 im Blasenkarzinom. Eine Korrelation von LASP1-Expression mit Prognose konnte mittels TCGA Daten für das Blasenkarzinom nicht festgestellt werden. Jedoch lagen lediglich Expressionsdaten auf mRNA Level vor, die meisten LASP1 mit Prognose assoziierenden Studien basieren hingegen auf Immunhistochemie, also der Expression auf Proteinlevel, welche in Blasenkrebszelllinien von der Expression auf mRNA Level abweichen kann. Die generierten Zelllinien wiesen nach lentiviraler Transduktion, Selektion und Sorten im Vergleich zum Wildtyp teilweise veränderte Zelleigenschaften auf, und ein Verlust des Fluoreszenzsignals des der shRNA vorangestellten tRFP wurde beobachtet. Daher müssen die Zellen bei weiterer Verwendung regelmäßig mit Puromycin nachselektioniert werden und die Validität dieser Zellen als Modell für das Transitionalzellkarzinom, besonders im Xenograft Mausmodell, ist kritisch zu hinterfragen. Entsprechend sind die Ergebnisse dieser Arbeit im Einklang mit bisherigen Studien zu LASP1. Damit unterstreicht diese Arbeit einmal mehr die Relevanz von LASP1 in diversen Krebserkrankungen. Weitere Studien zum Wert von LASP1 als prognostischer oder gar diagnostischer Marker erscheinen daher vielversprechend. N2 - The LIM and SH3 protein 1 (LASP1) plays key roles as a nucleo-cytoplasmic shuttling protein and a putative transcriptional co-factor in various physiological and pathological processes including development, cell structure, cell signaling, tumorigenesis, and metastasis. Moreover, LASP1 is overexpressed in a broad range of cancers. In several studies, the overexpression of LASP1 has been linked to increased tumor aggressiveness in vitro and in vivo. Furthermore, in various tumor entities, like breast carcinoma and colorectal carcinoma LASP1 expression correlates with worse prognosis. Recently, LASP1 has been evaluated as a marker for the transitional cell carcinoma (TCC), especially for TCC recurrence due to limitations in case of hematuria. TCC is the fourth most common cancer in men, with a high recurrence rate. To date, there is no established bona fide marker for predicting recurrence. Hence, expensive cystoscopy is still the gold standard in followup examinations. Earlier work, however, demonstrated that the LASP1 protein concentration in urinary cell pellets has good predictive values for TCC recurrence. Here, the functional role of LASP1 in TCC was investigated. Thus, the invasive TCC cell line T24 and the non-invasive TCC cell line RT4, which both presented a fourfold higher LASP1 protein expression than normal urothelium, were lentiviral transduced with an inducible shRNA expression system directed against LASP1. With those cell lines the impact of LASP1 knockdown on proliferation, migration, and adhesion was assessed. At a knock down efficiency of around 50%, adhesion and proliferation remained unchanged, but migration was significantly reduced. Moreover, cytoplasmic and nuclear localization of LASP1 was observed in protein extracts from the TCC cell lines. Interestingly, serine 146 phosphorylated LASP1 was primarily located in the nucleus. Furthermore, analysis of microRNA expression data from The Cancer Genome Atlas project indicated a potential regulation of LASP1 expression by mir-203 in TCC. Hence, those findings are consistent with previous reports on LASP1 in other cancer entities and confirm again the important role of LASP1 in cancers. In conclusion, LASP1 is highly overexpressed in TCC and has impact on migration, possibly due to its nuclear localization and intranuclear interactions. Future studies have to identify the nuclear interaction partners and to validate the value of LASP1 as a diagnostic and prognostic biomarker in the TCC. KW - Biomarker KW - Urothelkrebs KW - LASP1 Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-161309 ER - TY - JOUR A1 - Eisenhardt, Anja E. A1 - Sprenger, Adrian A1 - Röring, Michael A1 - Herr, Ricarda A1 - Weinberg, Florian A1 - Köhler, Martin A1 - Braun, Sandra A1 - Orth, Joachim A1 - Diedrich, Britta A1 - Lanner, Ulrike A1 - Tscherwinski, Natalja A1 - Schuster, Simon A1 - Dumaz, Nicolas A1 - Schmidt, Enrico A1 - Baumeister, Ralf A1 - Schlosser, Andreas A1 - Dengjel, Jörn A1 - Brummer, Tilman T1 - Phospho-proteomic analyses of B-Raf protein complexes reveal new regulatory principles JF - Oncotarget N2 - B-Raf represents a critical physiological regulator of the Ras/RAF/MEK/ERK-pathway and a pharmacological target of growing clinical relevance, in particular in oncology. To understand how B-Raf itself is regulated, we combined mass spectrometry with genetic approaches to map its interactome in MCF-10A cells as well as in B-Raf deficient murine embryonic fibroblasts (MEFs) and B-Raf/Raf-1 double deficient DT40 lymphoma cells complemented with wildtype or mutant B-Raf expression vectors. Using a multi-protease digestion approach, we identified a novel ubiquitination site and provide a detailed B-Raf phospho-map. Importantly, we identify two evolutionary conserved phosphorylation clusters around T401 and S419 in the B-Raf hinge region. SILAC labelling and genetic/biochemical follow-up revealed that these clusters are phosphorylated in the contexts of oncogenic Ras, sorafenib induced Raf dimerization and in the background of the V600E mutation. We further show that the vemurafenib sensitive phosphorylation of the T401 cluster occurs in trans within a Raf dimer. Substitution of the Ser/Thr-residues of this cluster by alanine residues enhances the transforming potential of B-Raf, indicating that these phosphorylation sites suppress its signaling output. Moreover, several B-Raf phosphorylation sites, including T401 and S419, are somatically mutated in tumors, further illustrating the importance of phosphorylation for the regulation of this kinase. KW - BRAF KW - proteomics KW - phosphorylation KW - sorafenib KW - protein-protein interaction Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166529 VL - 7 IS - 18 ER - TY - JOUR A1 - Orth, Martin F. A1 - Cazes, Alex A1 - Butt, Elke A1 - Grunewald, Thomas G. P. T1 - An update on the LIM and SH3 domain protein 1 (LASP1): a versatile structural, signaling, and biomarker protein JF - Oncotarget N2 - The gene encoding the LIM and SH3 domain protein (LASP1) was cloned two decades ago from a cDNA library of breast cancer metastases. As the first protein of a class comprising one N-terminal LIM and one C-terminal SH3 domain, LASP1 founded a new LIM-protein subfamily of the nebulin group. Since its discovery LASP1 proved to be an extremely versatile protein because of its exceptional structure allowing interaction with various binding partners, its ubiquitous expression in normal tissues, albeit with distinct expression patterns, and its ability to transmit signals from the cytoplasm into the nucleus. As a result, LASP1 plays key roles in cell structure, physiological processes, and cell signaling. Furthermore, LASP1 overexpression contributes to cancer aggressiveness hinting to a potential value of LASP1 as a cancer biomarker. In this review we summarize published data on structure, regulation, function, and expression pattern of LASP1, with a focus on its role in human cancer and as a biomarker protein. In addition, we provide a comprehensive transcriptome analysis of published microarrays (n=2,780) that illustrates the expression profile of LASP1 in normal tissues and its overexpression in a broad range of human cancer entities. KW - LASP1 KW - cancer KW - biomarker KW - microRNA KW - nucleo-cytoplasmic Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-144546 VL - 6 IS - 1 ER - TY - JOUR A1 - Endres, Marcel A1 - Kneitz, Susanne A1 - Orth, Martin F. A1 - Perera, Ruwan K. A1 - Zernecke, Alma A1 - Butt, Elke T1 - Regulation of matrix metalloproteinases (MMPs) expression and secretion in MDA-MB-231 breast cancer cells by LIM and SH3 protein 1 (LASP1) JF - Oncotarget N2 - The process of tumor invasion requires degradation of extracellular matrix by proteolytic enzymes. Cancer cells form protrusive invadopodia, which produce and release matrix metalloproteinases (MMPs) to degrade the basement membrane thereby enabling metastasis. We investigated the effect of LASP1, a newly identified protein in invadopodia, on expression, secretion and activation of MMPs in invasive breast tumor cell lines. By analyzing microarray data of in-house generated control and LASP1-depleted MDA-MB-231 breast cancer cells, we observed downregulation of MMP1, -3 and -9 upon LASP1 depletion. This was confirmed by Western blot analysis. Conversely, rescue experiments restored in part MMP expression and secretion. The regulatory effect of LASP1 on MMP expression was also observed in BT-20 breast cancer cells as well as in prostate and bladder cancer cell lines. In line with bioinformatic FunRich analysis of our data, which mapped a high regulation of transcription factors by LASP1, public microarray data analysis detected a correlation between high LASP1 expression and enhanced c-Fos levels, a protein that is part of the transcription factor AP-1 and known to regulate MMP expression. Compatibly, in luciferase reporter assays, AP-1 showed a decreased transcriptional activity after LASP1 knockdown. Zymography assays and Western blot analysis revealed an additional promotion of MMP secretion into the extracellular matrix by LASP1, thus, most likely, altering the microenvironment during cancer progression. The newly identified role of LASP1 in regulating matrix degradation by affecting MMP transcription and secretion elucidated the migratory potential of LASP1 overexpressing aggressive tumor cells in earlier studies. KW - LASP1 KW - c-Fos KW - extracellular matrix KW - AP-1 KW - matrix metalloproteinases KW - breast cancer Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176920 VL - 7 IS - 39 ER - TY - JOUR A1 - Herrmann, Andreas B. A1 - Müller, Martha‐Lena A1 - Orth, Martin F. A1 - Müller, Jörg P. A1 - Zernecke, Alma A1 - Hochhaus, Andreas A1 - Ernst, Thomas A1 - Butt, Elke A1 - Frietsch, Jochen J. T1 - Knockout of LASP1 in CXCR4 expressing CML cells promotes cell persistence, proliferation and TKI resistance JF - Journal of Cellular and Molecular Medicine N2 - Chronic myeloid leukaemia (CML) is a clonal myeloproliferative stem cell disorder characterized by the constitutively active BCR‐ABL tyrosine kinase. The LIM and SH3 domain protein 1 (LASP1) has recently been identified as a novel BCR‐ABL substrate and is associated with proliferation, migration, tumorigenesis and chemoresistance in several cancers. Furthermore, LASP1 was shown to bind to the chemokine receptor 4 (CXCR4), thought to be involved in mechanisms of relapse. In order to identify potential LASP1‐mediated pathways and related factors that may help to further eradicate minimal residual disease (MRD), the effect of LASP1 on processes involved in progression and maintenance of CML was investigated. The present data indicate that not only overexpression of CXCR4, but also knockout of LASP1 contributes to proliferation, reduced apoptosis and migration as well as increased adhesive potential of K562 CML cells. Furthermore, LASP1 depletion in K562 CML cells leads to decreased cytokine release and reduced NK cell‐mediated cytotoxicity towards CML cells. Taken together, these results indicate that in CML, reduced levels of LASP1 alone and in combination with high CXCR4 expression may contribute to TKI resistance. KW - BCR‐ABL KW - CML KW - CXCR4 KW - LASP1 KW - nilotinib KW - precursor cells Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-214122 VL - 24 IS - 5 SP - 2942 EP - 2955 ER -