@article{OrthCazesButtetal.2015, author = {Orth, Martin F. and Cazes, Alex and Butt, Elke and Grunewald, Thomas G. P.}, title = {An update on the LIM and SH3 domain protein 1 (LASP1): a versatile structural, signaling, and biomarker protein}, series = {Oncotarget}, volume = {6}, journal = {Oncotarget}, number = {1}, doi = {10.18632/oncotarget.3083}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-144546}, pages = {26-42}, year = {2015}, abstract = {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.}, language = {en} } @article{StoeltingWiesnervanVlietetal.2012, author = {St{\"o}lting, Miriam and Wiesner, Christiane and van Vliet, Vanessa and Butt, Elke and Pavenst{\"a}dt, Hermann and Linder, Stefan and Kremerskothen, Joachim}, title = {Lasp-1 Regulates Podosome Function}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {4}, doi = {10.1371/journal.pone.0035340}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-134315}, pages = {e35340}, year = {2012}, abstract = {Eukaryotic cells form a variety of adhesive structures to connect with their environment and to regulate cell motility. In contrast to classical focal adhesions, podosomes, highly dynamic structures of different cell types, are actively engaged in matrix remodelling and degradation. Podosomes are composed of an actin-rich core region surrounded by a ring-like structure containing signalling molecules, motor proteins as well as cytoskeleton-associated proteins. Lasp-1 is a ubiquitously expressed, actin-binding protein that is known to regulate cytoskeleton architecture and cell migration. This multidomain protein is predominantely present at focal adhesions, however, a second pool of Lasp-1 molecules is also found at lamellipodia and vesicle-like microdomains in the cytosol. In this report, we show that Lasp-1 is a novel component and regulator of podosomes. Immunofluorescence studies reveal a localization of Lasp-1 in the podosome ring structure, where it colocalizes with zyxin and vinculin. Life cell imaging experiments demonstrate that Lasp-1 is recruited in early steps of podosome assembly. A siRNA-mediated Lasp-1 knockdown in human macrophages affects podosome dynamics as well as their matrix degradation capacity. In summary, our data indicate that Lasp-1 is a novel component of podosomes and is involved in the regulation of podosomal function.}, language = {en} } @article{FrietschKastnerGrunewaldetal.2014, author = {Frietsch, Jochen J. and Kastner, Carolin and Grunewald, Thomas G.P. and Schweigel, Hardy and Nollau, Peter and Ziermann, Janine and Clement, Joachim H. and La Res{\´e}e, Paul and Hochhaus, Andreas and Butt, Elke}, title = {LASP1 is a novel BCR-ABL substrate and a phosphorylation-dependent binding partner of CRKL in chronic myeloid leukemia}, series = {Oncotarget}, volume = {5}, journal = {Oncotarget}, number = {14}, issn = {1949-2553}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-120639}, pages = {5257-71}, year = {2014}, abstract = {Chronic myeloid leukemia (CML) is characterized by a genomic translocation generating a permanently active BCR-ABL oncogene with a complex pattern of atypically tyrosine-phosphorylated proteins that drive the malignant phenotype of CML. Recently, the LIM and SH3 domain protein 1 (LASP1) was identified as a component of a six gene signature that is strongly predictive for disease progression and relapse in CML patients. However, the underlying mechanisms why LASP1 expression correlates with dismal outcome remained unresolved. Here, we identified LASP1 as a novel and overexpressed direct substrate of BCR-ABL in CML. We demonstrate that LASP1 is specifically phosphorylated by BCR-ABL at tyrosine-171 in CML patients, which is abolished by tyrosine kinase inhibitor therapy. Further studies revealed that LASP1 phosphorylation results in an association with CRKL - another specific BCR-ABL substrate and bona fide biomarker for BCR-ABL activity. pLASP1-Y171 binds to non-phosphorylated CRKL at its SH2 domain. Accordingly, the BCR-ABL-mediated pathophysiological hyper-phosphorylation of LASP1 in CML disrupts normal regulation of CRKL and LASP1, which likely has implications on downstream BCR-ABL signaling. Collectively, our results suggest that LASP1 phosphorylation might serve as an additional candidate biomarker for assessment of BCR-ABL activity and provide a first step toward a molecular understanding of LASP1 function in CML.}, language = {en} } @article{VamanVSPoppeHoubenetal.2015, author = {Vaman V. S., Anjana and Poppe, Heiko and Houben, Roland and Grunewald, Thomas G. P. and Goebeler, Matthias and Butt, Elke}, title = {LASP1, a Newly Identified Melanocytic Protein with a Possible Role in Melanin Release, but Not in Melanoma Progression}, series = {PLoS One}, volume = {10}, journal = {PLoS One}, number = {6}, doi = {10.1371/journal.pone.0129219}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-125994}, pages = {e0129219}, year = {2015}, abstract = {The LIM and SH3 protein 1 (LASP1) is a focal adhesion protein. Its expression is increased in many malignant tumors. However, little is known about the physiological role of the protein. In the present study, we investigated the expression and function of LASP1 in normal skin, melanocytic nevi and malignant melanoma. In normal skin, a distinct LASP1 expression is visible only in the basal epidermal layer while in nevi LASP1 protein is detected in all melanocytes. Melanoma exhibit no increase in LASP1 mRNA compared to normal skin. In melanocytes, the protein is bound to dynamin and mainly localized at late melanosomes along the edges and at the tips of the cell. Knockdown of LASP1 results in increased melanin concentration in the cells. Collectively, we identified LASP1 as a hitherto unknown protein in melanocytes and as novel partner of dynamin in the physiological process of membrane constriction and melanosome vesicle release.}, language = {en} } @article{HailerGrunewaldOrthetal.2014, author = {Hailer, Amelie and Grunewald, Thomas G. P. and Orth, Martin and Reiss, Cora and Kneitz, Burkhard and Spahn, Martin and Butt, Elke}, title = {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}, series = {Oncotarget}, volume = {5}, journal = {Oncotarget}, number = {12}, issn = {1949-2553}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-120540}, pages = {4144-53}, year = {2014}, abstract = {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.}, language = {en} } @article{WernerSchwedeGenieseretal.2011, author = {Werner, Katharina and Schwede, Frank and Genieser, Hans-Gottfried and Geiger, J{\"o}rg and Butt, Elke}, title = {Quantification of cAMP and cGMP analogs in intact cells: pitfalls in enzyme immunoassays for cyclic nucleotides}, series = {Naunyn-Schmiedeberg's Archives of Pharmacology}, volume = {384}, journal = {Naunyn-Schmiedeberg's Archives of Pharmacology}, number = {2}, doi = {10.1007/s00210-011-0662-6}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-141828}, pages = {169-176}, year = {2011}, abstract = {Immunoassays are routinely used as research tools to measure intracellular cAMP and cGMP concentrations. Ideally, this application requires antibodies with high sensitivity and specificity. The present work evaluates the cross-reactivity of commercially available cyclic nucleotide analogs with two non-radioactive and one radioactive cAMP and cGMP immunoassay. Most of the tested cyclic nucleotide analogs showed low degree competition with the antibodies; however, with Rp-cAMPS, 8-Br-cGMP and 8-pCPT-cGMP, a strong cross-reactivity with the corresponding cAMP and cGMP, respectively, immunoassays was observed. The determined EIA-binding constants enabled the measurement of the intracellular cyclic nucleotide concentrations and revealed a time- and lipophilicity-dependent cell membrane permeability of the compounds in the range of 10-30\% of the extracellular applied concentration, thus allowing a more accurate prediction of the intracellular analog levels in a given experiment.}, language = {en} }