@article{TeutschbeinHaydnSamansetal.2010, author = {Teutschbein, Janka and Haydn, Johannes M. and Samans, Birgit and Krause, Michael and Eilers, Martin and Schartl, Manfred and Meierjohann, Svenja}, title = {Gene expression analysis after receptor tyrosine kinase activation reveals new potential melanoma proteins}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-67900}, year = {2010}, abstract = {Background: Melanoma is an aggressive tumor with increasing incidence. To develop accurate prognostic markers and targeted therapies, changes leading to malignant transformation of melanocytes need to be understood. In the Xiphophorus melanoma model system, a mutated version of the EGF receptor Xmrk (Xiphophorus melanoma receptor kinase) triggers melanomagenesis. Cellular events downstream of Xmrk, such as the activation of Akt, Ras, B-Raf or Stat5, were also shown to play a role in human melanomagenesis. This makes the elucidation of Xmrk downstream targets a useful method for identifying processes involved in melanoma formation. Methods: Here, we analyzed Xmrk-induced gene expression using a microarray approach. Several highly expressed genes were confirmed by realtime PCR, and pathways responsible for their induction were revealed using small molecule inhibitors. The expression of these genes was also monitored in human melanoma cell lines, and the target gene FOSL1 was knocked down by siRNA. Proliferation and migration of siRNA-treated melanoma cell lines were then investigated. Results: Genes with the strongest upregulation after receptor activation were FOS-like antigen 1 (Fosl1), early growth response 1 (Egr1), osteopontin (Opn), insulin-like growth factor binding protein 3 (Igfbp3), dual-specificity phosphatase 4 (Dusp4), and tumor-associated antigen L6 (Taal6). Interestingly, most genes were blocked in presence of a SRC kinase inhibitor. Importantly, we found that FOSL1, OPN, IGFBP3, DUSP4, and TAAL6 also exhibited increased expression levels in human melanoma cell lines compared to human melanocytes. Knockdown of FOSL1 in human melanoma cell lines reduced their proliferation and migration. Conclusion: Altogether, the data show that the receptor tyrosine kinase Xmrk is a useful tool in the identification of target genes that are commonly expressed in Xmrk-transgenic melanocytes and melanoma cell lines. The identified molecules constitute new possible molecular players in melanoma development. Specifically, a role of FOSL1 in melanomagenic processes is demonstrated. These data are the basis for future detailed analyses of the investigated target genes.}, language = {en} } @article{HoennemannSanzMorenoWolfetal.2012, author = {H{\"o}nnemann, Jan and Sanz-Moreno, Adrian and Wolf, Elmar and Eilers, Martin and Els{\"a}sser, Hans-Peter}, title = {Miz1 Is a Critical Repressor of cdkn1a during Skin Tumorigenesis}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {4}, doi = {10.1371/journal.pone.0034885}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133285}, pages = {e34885}, year = {2012}, abstract = {The transcription factor Miz1 forms repressive DNA-binding complexes with the Myc, Gfi-1 and Bcl-6 oncoproteins. Known target genes of these complexes encode the cyclin-dependent kinase inhibitors (CKIs) cdkn2b (p15\(^{Ink4}\)), cdkn1a (p21\(^{Cip1}\)), and cdkn1c (p57\(^{Kip2}\)). Whether Miz1-mediated repression is important for control of cell proliferation in vivo and for tumor formation is unknown. Here we show that deletion of the Miz1 POZ domain, which is critical for Miz1 function, restrains the development of skin tumors in a model of chemically-induced, Ras-dependent tumorigenesis. While the stem cell compartment appears unaffected, interfollicular keratinocytes lacking functional Miz1 exhibit a reduced proliferation and an accelerated differentiation of the epidermis in response to the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Tumorigenesis, proliferation and normal differentiation are restored in animals lacking cdkn1a, but not in those lacking cdkn2b. Our data demonstrate that Miz1-mediated attenuation of cell cycle arrest pathways via repression of cdkn1a has a critical role during tumorigenesis in the skin.}, language = {en} } @article{HeisigWeberEnglbergeretal.2012, author = {Heisig, Julia and Weber, David and Englberger, Eva and Winkler, Anja and Kneitz, Susanne and Sung, Wing-Kin and Wolf, Elmar and Eilers, Martin and Wei, Chia-Lin and Gessler, Manfred}, title = {Target Gene Analysis by Microarrays and Chromatin Immunoprecipitation Identifies HEY Proteins as Highly Redundant bHLH Repressors}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75341}, year = {2012}, abstract = {HEY bHLH transcription factors have been shown to regulate multiple key steps in cardiovascular development. They can be induced by activated NOTCH receptors, but other upstream stimuli mediated by TGFß and BMP receptors may elicit a similar response. While the basic and helix-loop-helix domains exhibit strong similarity, large parts of the proteins are still unique and may serve divergent functions. The striking overlap of cardiac defects in HEY2 and combined HEY1/HEYL knockout mice suggested that all three HEY genes fulfill overlapping function in target cells. We therefore sought to identify target genes for HEY proteins by microarray expression and ChIPseq analyses in HEK293 cells, cardiomyocytes, and murine hearts. HEY proteins were found to modulate expression of their target gene to a rather limited extent, but with striking functional interchangeability between HEY factors. Chromatin immunoprecipitation revealed a much greater number of potential binding sites that again largely overlap between HEY factors. Binding sites are clustered in the proximal promoter region especially of transcriptional regulators or developmental control genes. Multiple lines of evidence suggest that HEY proteins primarily act as direct transcriptional repressors, while gene activation seems to be due to secondary or indirect effects. Mutagenesis of putative DNA binding residues supports the notion of direct DNA binding. While class B E-box sequences (CACGYG) clearly represent preferred target sequences, there must be additional and more loosely defined modes of DNA binding since many of the target promoters that are efficiently bound by HEY proteins do not contain an Ebox motif. These data clearly establish the three HEY bHLH factors as highly redundant transcriptional repressors in vitro and in vivo, which explains the combinatorial action observed in different tissues with overlapping expression.}, subject = {Biologie}, language = {en} } @article{WiegeringPfannUtheetal.2013, author = {Wiegering, Armin and Pfann, Christina and Uthe, Friedrich Wilhelm and Otto, Christoph and Rycak, Lukas and M{\"a}der, Uwe and Gasser, Martin and Waaga-Gasser, Anna-Maria and Eilers, Martin and Germer, Christoph-Thomas}, title = {CIP2A Influences Survival in Colon Cancer and Is Critical for Maintaining Myc Expression}, series = {PLoS ONE}, journal = {PLoS ONE}, doi = {10.1371/journal.pone.0075292}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-97252}, year = {2013}, abstract = {The cancerous inhibitor of protein phosphatase 2A (CIP2A) is an oncogenic factor that stabilises the c-Myc protein. CIP2A is overexpressed in several tumours, and expression levels are an independent marker for long-term outcome. To determine whether CIP2A expression is elevated in colon cancer and whether it might serve as a prognostic marker for survival, we analysed CIP2A mRNA expression by real-time PCR in 104 colon cancer samples. CIP2A mRNA was overexpressed in colon cancer samples and CIP2A expression levels correlated significantly with tumour stage. We found that CIP2A serves as an independent prognostic marker for disease-free and overall survival. Further, we investigated CIP2A-dependent effects on levels of c-Myc, Akt and on cell proliferation in three colon cancer cell lines by silencing CIP2A using small interfering (si) and short hairpin (sh) RNAs. Depletion of CIP2A substantially inhibited growth of colon cell lines and reduced c-Myc levels without affecting expression or function of the upstream regulatory kinase, Akt. Expression of CIP2A was found to be dependent on MAPK activity, linking elevated c-Myc expression to deregulated signal transduction in colon cancer.}, language = {en} } @article{SchueleinVoelkWolfZhuetal.2014, author = {Sch{\"u}lein-V{\"o}lk, Christina and Wolf, Elmar and Zhu, Jing and Xu, Wenshan and Taranets, Lyudmyla and Hellmann, Andreas and J{\"a}nicke, Laura A. and Diefenbacher, Markus E. and Behrens, Axel and Eilers, Martin and Popov, Nikita}, title = {Dual Regulation of Fbw7 Function and Oncogenic Transformation by Usp28}, series = {CELL REPORTS}, volume = {9}, journal = {CELL REPORTS}, number = {3}, issn = {2211-1247}, doi = {10.1016/j.celrep.2014.09.057}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-118219}, pages = {1099-1109}, year = {2014}, abstract = {Fbw7, the substrate recognition subunit of SCF(Fbw7) ubiquitin ligase, mediates the turnover of multiple proto-oncoproteins and promotes its own degradation. Fbw7-dependent substrate ubiquitination is antagonized by the Usp28 deubiquitinase. Here, we show that Usp28 preferentially antagonizes autocatalytic ubiquitination and stabilizes Fbw7, resulting in dose-dependent effects in Usp28 knockout mice. Monoallelic deletion of Usp28 maintains stable Fbw7 but drives Fbw7 substrate degradation. In contrast, complete knockout triggers Fbw7 degradation and leads to the accumulation of Fbw7 substrates in several tissues and embryonic fibroblasts. On the other hand, overexpression of Usp28 stabilizes both Fbw7 and its substrates. Consequently, both complete loss and ectopic expression of Usp28 promote Ras-driven oncogenic transformation. We propose that dual regulation of Fbw7 activity by Usp28 is a safeguard mechanism for maintaining physiological levels of proto-oncogenic Fbw7 substrates, which is equivalently disrupted by loss or overexpression of Usp28.}, language = {en} } @article{SanzMorenoFuhrmannWolfetal.2014, author = {Sanz-Moreno, Adrian and Fuhrmann, David and Wolf, Elmar and von Eyss, Bj{\"o}rn and Eilers, Martin and Els{\"a}sser, Hans-Peter}, title = {Miz1 Deficiency in the Mammary Gland Causes a Lactation Defect by Attenuated Stat5 Expression and Phosphorylation}, series = {PLOS ONE}, volume = {9}, journal = {PLOS ONE}, number = {2}, doi = {10.1371/journal.pone.0089187}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-117286}, pages = {e89187}, year = {2014}, abstract = {Miz1 is a zinc finger transcription factor with an N-terminal POZ domain. Complexes with Myc, Bcl-6 or Gfi-1 repress expression of genes like Cdkn2b (p15(Ink4)) or Cd-kn1a (p21(Cip1)). The role of Miz1 in normal mammary gland development has not been addressed so far. Conditional knockout of the Miz1 POZ domain in luminal cells during pregnancy caused a lactation defect with a transient reduction of glandular tissue, reduced proliferation and attenuated differentiation. This was recapitulated in vitro using mouse mammary gland derived HC11 cells. Further analysis revealed decreased Stat5 activity in Miz1 Delta POZ mammary glands and an attenuated expression of Stat5 targets. Gene expression of the Prolactin receptor (PrlR) and ErbB4, both critical for Stat5 phosphorylation (pStat5) or pStat5 nuclear translocation, was decreased in Miz1 Delta POZ females. Microarray, ChIP-Seq and gene set enrichment analysis revealed a down-regulation of Miz1 target genes being involved in vesicular transport processes. Our data suggest that deranged intracellular transport and localization of PrlR and ErbB4 disrupt the Stat5 signalling pathway in mutant glands and cause the observed lactation phenotype.}, language = {en} } @article{PeterBultinckMyantetal.2014, author = {Peter, Stefanie and Bultinck, Jennyfer and Myant, Kevin and Jaenicke, Laura A. and Walz, Susanne and M{\"u}ller, Judith and Gmachl, Michael and Treu, Matthias and Boehmelt, Guido and Ade, Casten P. and Schmitz, Werner and Wiegering, Armin and Otto, Christoph and Popov, Nikita and Sansom, Owen and Kraut, Norbert and Eilers, Martin}, title = {H Tumor cell-specific inhibition of MYC function using small molecule inhibitors of the HUWE1 ubiquitin ligase}, series = {EMBO Molecular Medicine}, volume = {6}, journal = {EMBO Molecular Medicine}, number = {12}, issn = {1757-4684}, doi = {10.15252/emmm.201403927}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-118132}, pages = {1525-41}, year = {2014}, abstract = {Deregulated expression of MYC is a driver of colorectal carcinogenesis, necessitating novel strategies to inhibit MYC function. The ubiquitin ligase HUWE1 (HECTH9, ARF-BP1, MULE) associates with both MYC and the MYC-associated protein MIZ1. We show here that HUWE1 is required for growth of colorectal cancer cells in culture and in orthotopic xenograft models. Using high-throughput screening, we identify small molecule inhibitors of HUWE1, which inhibit MYC-dependent transactivation in colorectal cancer cells, but not in stem and normal colon epithelial cells. Inhibition of HUWE1 stabilizes MIZ1. MIZ1 globally accumulates on MYC target genes and contributes to repression of MYC-activated target genes upon HUWE1 inhibition. Our data show that transcriptional activation by MYC in colon cancer cells requires the continuous degradation of MIZ1 and identify a novel principle that allows for inhibition of MYC function in tumor cells.}, language = {en} } @article{MuthalaguJunttilaWieseetal.2014, author = {Muthalagu, Nathiya and Junttila, Melissa R. and Wiese, Kathrin E. and Wolf, Elmar and Morton, Jennifer and Bauer, Barbara and Evan, Gerard I. and Eilers, Martin and Murphy, Daniel J.}, title = {BIM Is the Primary Mediator of MYC-Induced Apoptosis in Multiple Solid Tissues}, series = {Cell Reports}, volume = {8}, journal = {Cell Reports}, number = {5}, doi = {10.1016/j.celrep.2014.07.057}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-115370}, pages = {1347-1353}, year = {2014}, abstract = {MYC is one of the most frequently overexpressed oncogenes in human cancer, and even modestly deregulated MYC can initiate ectopic proliferation in many postmitotic cell types in vivo. Sensitization of cells to apoptosis limits MYC's oncogenic potential. However, the mechanism through which MYC induces apoptosis is controversial. Some studies implicate p19ARF-mediated stabilization of p53, followed by induction of proapoptotic BH3 proteins NOXA and PUMA, whereas others argue for direct regulation of BH3 proteins, especially BIM. Here, we use a single experimental system to systematically evaluate the roles of p19ARF and BIM during MYC-induced apoptosis, in vitro, in vivo, and in combination with a widely used chemotherapeutic, doxorubicin. We find a common specific requirement for BIM during MYC-induced apoptosis in multiple settings, which does not extend to the p53-responsive BH3 family member PUMA, and find no evidence of a role for p19ARF during MYC-induced apoptosis in the tissues examined.}, language = {en} } @article{ElkonLoayzaPuchKorkmazetal.2015, author = {Elkon, Ran and Loayza-Puch, Fabricio and Korkmaz, Gozde and Lopes, Rui and van Breugel, Pieter C and Bleijerveld, Onno B and Altelaar, AF Maarten and Wolf, Elmar and Lorenzin, Francesca and Eilers, Martin and Agami, Reuven}, title = {Myc coordinates transcription and translation to enhance transformation and suppress invasiveness}, series = {EMBO reports}, volume = {16}, journal = {EMBO reports}, number = {12}, doi = {10.15252/embr.201540717}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-150373}, pages = {1723-1736}, year = {2015}, abstract = {c-Myc is one of the major human proto-oncogenes and is often associated with tumor aggression and poor clinical outcome. Paradoxically, Myc was also reported as a suppressor of cell motility, invasiveness, and metastasis. Among the direct targets of Myc are many components of the protein synthesis machinery whose induction results in an overall increase in protein synthesis that empowers tumor cell growth. At present, it is largely unknown whether beyond the global enhancement of protein synthesis, Myc activation results in translation modulation of specific genes. Here, we measured Myc-induced global changes in gene expression at the transcription, translation, and protein levels and uncovered extensive transcript-specific regulation of protein translation. Particularly, we detected a broad coordination between regulation of transcription and translation upon modulation of Myc activity and showed the connection of these responses to mTOR signaling to enhance oncogenic transformation and to the TGFβ pathway to modulate cell migration and invasiveness. Our results elucidate novel facets of Myc-induced cellular responses and provide a more comprehensive view of the consequences of its activation in cancer cells.}, language = {en} } @article{MederKoenigOzretićetal.2016, author = {Meder, Lydia and K{\"o}nig, Katharina and Ozretić, Luka and Schultheis, Anne M. and Ueckeroth, Frank and Ade, Carsten P. and Albus, Kerstin and Boehm, Diana and Rommerscheidt-Fuss, Ursula and Florin, Alexandra and Buhl, Theresa and Hartmann, Wolfgang and Wolf, J{\"u}rgen and Merkelbach-Bruse, Sabine and Eilers, Martin and Perner, Sven and Heukamp, Lukas C. and Buettner, Reinhard}, title = {NOTCH, ASCL1, p53 and RB alterations define an alternative pathway driving neuroendocrine and small cell lung carcinomas}, series = {International Journal of Cancer}, volume = {138}, journal = {International Journal of Cancer}, number = {4}, doi = {10.1002/ijc.29835}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-190853}, pages = {927-938}, year = {2016}, abstract = {Small cell lung cancers (SCLCs) and extrapulmonary small cell cancers (SCCs) are very aggressive tumors arising de novo as primary small cell cancer with characteristic genetic lesions in RB1 and TP53. Based on murine models, neuroendocrine stem cells of the terminal bronchioli have been postulated as the cellular origin of primary SCLC. However, both in lung and many other organs, combined small cell/non-small cell tumors and secondary transitions from non-small cell carcinomas upon cancer therapy to neuroendocrine and small cell tumors occur. We define features of "small cell-ness" based on neuroendocrine markers, characteristic RB1 and TP53 mutations and small cell morphology. Furthermore, here we identify a pathway driving the pathogenesis of secondary SCLC involving inactivating NOTCH mutations, activation of the NOTCH target ASCL1 and canonical WNT-signaling in the context of mutual bi-allelic RB1 and TP53 lesions. Additionaly, we explored ASCL1 dependent RB inactivation by phosphorylation, which is reversible by CDK5 inhibition. We experimentally verify the NOTCH-ASCL1-RB-p53 signaling axis in vitro and validate its activation by genetic alterations in vivo. We analyzed clinical tumor samples including SCLC, SCC and pulmonary large cell neuroendocrine carcinomas and adenocarcinomas using amplicon-based Next Generation Sequencing, immunohistochemistry and fluorescence in situ hybridization. In conclusion, we identified a novel pathway underlying rare secondary SCLC which may drive small cell carcinomas in organs other than lung, as well.}, language = {en} } @article{LorenzinBenaryBaluapurietal.2016, author = {Lorenzin, Francesca and Benary, Uwe and Baluapuri, Apoorva and Walz, Susanne and Jung, Lisa Anna and von Eyss, Bj{\"o}rn and Kisker, Caroline and Wolf, Jana and Eilers, Martin and Wolf, Elmar}, title = {Different promoter affinities account for specificity in MYC-dependent gene regulation}, series = {eLife}, volume = {5}, journal = {eLife}, doi = {10.7554/eLife.15161}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-162913}, pages = {e15161}, year = {2016}, abstract = {Enhanced expression of the MYC transcription factor is observed in the majority of tumors. Two seemingly conflicting models have been proposed for its function: one proposes that MYC enhances expression of all genes, while the other model suggests gene-specific regulation. Here, we have explored the hypothesis that specific gene expression profiles arise since promoters differ in affinity for MYC and high-affinity promoters are fully occupied by physiological levels of MYC. We determined cellular MYC levels and used RNA- and ChIP-sequencing to correlate promoter occupancy with gene expression at different concentrations of MYC. Mathematical modeling showed that binding affinities for interactions of MYC with DNA and with core promoter-bound factors, such as WDR5, are sufficient to explain promoter occupancies observed in vivo. Importantly, promoter affinity stratifies different biological processes that are regulated by MYC, explaining why tumor-specific MYC levels induce specific gene expression programs and alter defined biological properties of cells.}, language = {en} } @article{SanderXuEilersetal.2017, author = {Sander, Bodo and Xu, Wenshan and Eilers, Martin and Popov, Nikita and Lorenz, Sonja}, title = {A conformational switch regulates the ubiquitin ligase HUWE1}, series = {eLife}, volume = {6}, journal = {eLife}, doi = {10.7554/eLife.21036}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-171862}, year = {2017}, abstract = {The human ubiquitin ligase HUWE1 has key roles in tumorigenesis, yet it is unkown how its activity is regulated. We present the crystal structure of a C-terminal part of HUWE1, including the catalytic domain, and reveal an asymmetric auto-inhibited dimer. We show that HUWE1 dimerizes in solution and self-associates in cells, and that both occurs through the crystallographic dimer interface. We demonstrate that HUWE1 is inhibited in cells and that it can be activated by disruption of the dimer interface. We identify a conserved segment in HUWE1 that counteracts dimer formation by associating with the dimerization region intramolecularly. Our studies reveal, intriguingly, that the tumor suppressor p14ARF binds to this segment and may thus shift the conformational equilibrium of HUWE1 toward the inactive state. We propose a model, in which the activity of HUWE1 underlies conformational control in response to physiological cues—a mechanism that may be exploited for cancer therapy.}, language = {en} } @unpublished{LoefflerMayerTrujilloVieraetal.2018, author = {L{\"o}ffler, Mona C. and Mayer, Alexander E. and Trujillo Viera, Jonathan and Loza Valdes, Angel and El-Merahib, Rabih and Ade, Carsten P. and Karwen, Till and Schmitz, Werner and Slotta, Anja and Erk, Manuela and Janaki-Raman, Sudha and Matesanz, Nuria and Torres, Jorge L. and Marcos, Miguel and Sabio, Guadalupe and Eilers, Martin and Schulze, Almut and Sumara, Grzegorz}, title = {Protein kinase D1 deletion in adipocytes enhances energy dissipation and protects against adiposity}, series = {The EMBO Journal}, journal = {The EMBO Journal}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176093}, year = {2018}, abstract = {Nutrient overload in combination with decreased energy dissipation promotes obesity and diabetes. Obesity results in a hormonal imbalance, which among others, activates G-protein coupled receptors utilizing diacylglycerol (DAG) as secondary messenger. Protein kinase D1 (PKD1) is a DAG effector which integrates multiple nutritional and hormonal inputs, but its physiological role in adipocytes is unknown. Here, we show that PKD1 promotes lipogenesis and suppresses mitochondrial fragmentation, biogenesis, respiration, and energy dissipation in an AMP-activated protein kinase (AMPK)-dependent manner. Moreover, mice lacking PKD1 in adipocytes are resistant to diet-induced obesity due to elevated energy expenditure. Beiging of adipocytes promotes energy expenditure and counteracts obesity. Consistently, deletion of PKD1 promotes expression of the β3-adrenergic receptor (ADRB3) in a CCAAT/enhancerbinding protein (C/EBP)-α and δ-dependent manner, which leads to the elevated expression of beige markers in adipocytes and subcutaneous adipose tissue. Finally, deletion of PKD1 in adipocytes improves insulin sensitivity and ameliorates liver steatosis. Thus, loss of PKD1 in adipocytes increases energy dissipation by several complementary mechanisms and might represent an attractive strategy to treat obesity and its related complications.}, language = {en} } @article{YankuBitmanLotanZoharetal.2018, author = {Yanku, Yifat and Bitman-Lotan, Eliya and Zohar, Yaniv and Kurant, Estee and Zilke, Norman and Eilers, Martin and Orian, Amir}, title = {Drosophila HUWE1 ubiquitin ligase regulates endoreplication and antagonizes JNK signaling during salivary gland development}, series = {Cells}, volume = {7}, journal = {Cells}, number = {10}, issn = {2073-4409}, doi = {10.3390/cells7100151}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-197630}, pages = {151}, year = {2018}, abstract = {The HECT-type ubiquitin ligase HECT, UBA and WWE Domain Containing 1, (HUWE1) regulates key cancer-related pathways, including the Myc oncogene. It affects cell proliferation, stress and immune signaling, mitochondria homeostasis, and cell death. HUWE1 is evolutionarily conserved from Caenorhabditis elegance to Drosophila melanogaster and Humans. Here, we report that the Drosophila ortholog, dHUWE1 (CG8184), is an essential gene whose loss results in embryonic lethality and whose tissue-specific disruption establishes its regulatory role in larval salivary gland development. dHUWE1 is essential for endoreplication of salivary gland cells and its knockdown results in the inability of these cells to replicate DNA. Remarkably, dHUWE1 is a survival factor that prevents premature activation of JNK signaling, thus preventing the disintegration of the salivary gland, which occurs physiologically during pupal stages. This function of dHUWE1 is general, as its inhibitory effect is observed also during eye development and at the organismal level. Epistatic studies revealed that the loss of dHUWE1 is compensated by dMyc proeitn expression or the loss of dmP53. dHUWE1 is therefore a conserved survival factor that regulates organ formation during Drosophila development.}, language = {en} } @article{Prieto‐GarciaHartmannReisslandetal.2020, author = {Prieto-Garcia, Cristian and Hartmann, Oliver and Reissland, Michaela and Braun, Fabian and Fischer, Thomas and Walz, Susanne and Sch{\"u}lein-V{\"o}lk, Christina and Eilers, Ursula and Ade, Carsten P. and Calzado, Marco A. and Orian, Amir and Maric, Hans M. and M{\"u}nch, Christian and Rosenfeldt, Mathias and Eilers, Martin and Diefenbacher, Markus E.}, title = {Maintaining protein stability of ∆Np63 via USP28 is required by squamous cancer cells}, series = {EMBO Molecular Medicine}, volume = {12}, journal = {EMBO Molecular Medicine}, number = {4}, doi = {10.15252/emmm.201911101}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218303}, year = {2020}, abstract = {The transcription factor ∆Np63 is a master regulator of epithelial cell identity and essential for the survival of squamous cell carcinoma (SCC) of lung, head and neck, oesophagus, cervix and skin. Here, we report that the deubiquitylase USP28 stabilizes ∆Np63 and maintains elevated ∆NP63 levels in SCC by counteracting its proteasome-mediated degradation. Impaired USP28 activity, either genetically or pharmacologically, abrogates the transcriptional identity and suppresses growth and survival of human SCC cells. CRISPR/Cas9-engineered in vivo mouse models establish that endogenous USP28 is strictly required for both induction and maintenance of lung SCC. Our data strongly suggest that targeting ∆Np63 abundance via inhibition of USP28 is a promising strategy for the treatment of SCC tumours.}, language = {en} } @article{OttoKastnerSchmidtetal.2022, author = {Otto, Christoph and Kastner, Carolin and Schmidt, Stefanie and Uttinger, Konstantin and Baluapuri, Apoorva and Denk, Sarah and Rosenfeldt, Mathias T. and Rosenwald, Andreas and Roehrig, Florian and Ade, Carsten P. and Schuelein-Voelk, Christina and Diefenbacher, Markus E. and Germer, Christoph-Thomas and Wolf, Elmar and Eilers, Martin and Wiegering, Armin}, title = {RNA polymerase I inhibition induces terminal differentiation, growth arrest, and vulnerability to senolytics in colorectal cancer cells}, series = {Molecular Oncology}, volume = {16}, journal = {Molecular Oncology}, number = {15}, doi = {10.1002/1878-0261.13265}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-312806}, pages = {2788-2809}, year = {2022}, abstract = {Ribosomal biogenesis and protein synthesis are deregulated in most cancers, suggesting that interfering with translation machinery may hold significant therapeutic potential. Here, we show that loss of the tumor suppressor adenomatous polyposis coli (APC), which constitutes the initiating event in the adenoma carcinoma sequence for colorectal cancer (CRC), induces the expression of RNA polymerase I (RNAPOL1) transcription machinery, and subsequently upregulates ribosomal DNA (rDNA) transcription. Targeting RNAPOL1 with a specific inhibitor, CX5461, disrupts nucleolar integrity, and induces a disbalance of ribosomal proteins. Surprisingly, CX5461-induced growth arrest is irreversible and exhibits features of senescence and terminal differentiation. Mechanistically, CX5461 promotes differentiation in an MYC-interacting zinc-finger protein 1 (MIZ1)- and retinoblastoma protein (Rb)-dependent manner. In addition, the inhibition of RNAPOL1 renders CRC cells vulnerable towards senolytic agents. We validated this therapeutic effect of CX5461 in murine- and patient-derived organoids, and in a xenograft mouse model. These results show that targeting ribosomal biogenesis together with targeting the consecutive, senescent phenotype using approved drugs is a new therapeutic approach, which can rapidly be transferred from bench to bedside.}, language = {en} } @article{DieboldSchoenemannEilersetal.2023, author = {Diebold, Mathias and Sch{\"o}nemann, Lars and Eilers, Martin and Sotriffer, Christoph and Schindelin, Hermann}, title = {Crystal structure of a covalently linked Aurora-A-MYCN complex}, series = {Acta Crystallographica}, volume = {D79}, journal = {Acta Crystallographica}, doi = {10.1107/s2059798322011433}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-318855}, pages = {1 -- 9}, year = {2023}, abstract = {Formation of the Aurora-A-MYCN complex increases levels of the oncogenic transcription factor MYCN in neuroblastoma cells by abrogating its degradation through the ubiquitin proteasome system. While some small-molecule inhibitors of Aurora-A were shown to destabilize MYCN, clinical trials have not been satisfactory to date. MYCN itself is considered to be `undruggable' due to its large intrinsically disordered regions. Targeting the Aurora-A-MYCN complex rather than Aurora-A or MYCN alone will open new possibilities for drug development and screening campaigns. To overcome the challenges that a ternary system composed of Aurora-A, MYCN and a small molecule entails, a covalently cross-linked construct of the Aurora-A-MYCN complex was designed, expressed and characterized, thus enabling screening and design campaigns to identify selective binders.}, language = {en} }