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1.
Nucleic Acids Res ; 52(7): 3823-3836, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38421639

RESUMO

Alternative splicing and multiple transcription start and termination sites can produce a diverse repertoire of mRNA transcript variants from a given gene. While the full picture of the human transcriptome is still incomplete, publicly available RNA datasets have enabled the assembly of transcripts. Using publicly available deep sequencing data from 927 human samples across 48 tissues, we quantified known and new transcript variants, provide an interactive, browser-based application Splice-O-Mat and demonstrate its relevance using adhesion G protein-coupled receptors (aGPCRs) as an example. On average, 24 different transcript variants were detected for each of the 33 human aGPCR genes, and several dominant transcript variants were not yet annotated. Variable transcription starts and complex exon-intron structures encode a flexible protein domain architecture of the N- and C termini and the seven-transmembrane helix domain (7TMD). Notably, we discovered the first GPCR (ADGRG7/GPR128) with eight transmembrane helices. Both the N- and C terminus of this aGPCR were intracellularly oriented, anchoring the N terminus in the plasma membrane. Moreover, the assessment of tissue-specific transcript variants, also for other gene classes, in our application may change the evaluation of disease-causing mutations, as their position in different transcript variants may explain tissue-specific phenotypes.


Assuntos
Processamento Alternativo , Sequenciamento de Nucleotídeos em Larga Escala , Receptores Acoplados a Proteínas G , Humanos , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/química , Transcriptoma/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Mensageiro/química , Éxons/genética , Domínios Proteicos
2.
Int J Cancer ; 151(9): 1542-1554, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35737508

RESUMO

Accurate classification of melanocytic tumors is important for prognostic evaluation, treatment and follow-up protocols of patients. The majority of melanocytic proliferations can be classified solely based on clinical and pathological criteria, however in select cases a definitive diagnostic assessment remains challenging and additional diagnostic biomarkers would be advantageous. We analyzed melanomas, nevi, Spitz nevi and atypical spitzoid tumors using parallel sequencing (exons of 611 genes and 507 gene translocation analysis) and methylation arrays (850k Illumina EPIC). By combining detailed genetic and epigenetic analysis with reference-based and reference-free DNA methylome deconvolution we compared Spitz nevi to nevi and melanoma and assessed the potential for these methods in classifying challenging spitzoid tumors. Results were correlated with clinical and histologic features. Spitz nevi were found to cluster independently of nevi and melanoma and demonstrated a different mutation profile. Multiple copy number alterations and TERT promoter mutations were identified only in melanomas. Genome-wide methylation in Spitz nevi was comparable to benign nevi while the Leukocytes UnMethylation for Purity (LUMP) algorithm in Spitz nevi was comparable to melanoma. Histologically difficult to classify Spitz tumor cases were assessed which, based on methylation arrays, clustered between Spitz nevi and melanoma and in terms of genetic profile or copy number variations demonstrated worrisome features suggesting a malignant neoplasm. Comprehensive sequencing and methylation analysis verify Spitz nevi as an independent melanocytic entity distinct from both nevi and melanoma. Combined genetic and methylation assays can offer additional insights in diagnosing difficult to classify Spitzoid tumors.


Assuntos
Melanoma , Nevo de Células Epitelioides e Fusiformes , Paraganglioma , Neoplasias Cutâneas , Variações do Número de Cópias de DNA , Diagnóstico Diferencial , Humanos , Melanoma/diagnóstico , Melanoma/genética , Melanoma/patologia , Metilação , Nevo de Células Epitelioides e Fusiformes/diagnóstico , Nevo de Células Epitelioides e Fusiformes/genética , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Síndrome
3.
Biochem Biophys Res Commun ; 589: 152-158, 2022 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-34922196

RESUMO

Latrophilins are highly conserved Adhesion GPCRs playing essential roles in the mammalian nervous system and are associated with severe neurological disorders. Recently, it has been shown that murine Latrophilins mediate classical G-protein signals to drive synaptogenesis. However, there is evidence that Latrophilins in the nematode Caenorhabditis elegans can also function independently of their seven-transmembrane domain and C terminus (trans function). Here, we show that Latrophilin-1 acts in trans to mediate morphogenesis of sensory structures in the C. elegans nervous system. This trans function is physiologically relevant in copulation behavior. Detailed expression and RNA-Seq analyses revealed specific LAT-1-positive neurons and first insights into the genetic network that is modulated by the receptor function. We conclude that 7TM-independent functions of Latrophilins are essential for neuronal physiology, possibly complementing canonical functions via G protein-mediated signaling.


Assuntos
Comportamento Animal , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Mecanotransdução Celular , Morfogênese , Neurônios/metabolismo , Receptores de Peptídeos/metabolismo , Animais , Caenorhabditis elegans/genética , Copulação , Masculino , Mutação/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma/genética
4.
BMC Genomics ; 22(1): 802, 2021 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-34743696

RESUMO

BACKGROUND: RNA-seq emerges as a valuable method for clinical genetics. The transcriptome is "dynamic" and tissue-specific, but typically the probed tissues to analyze (TA) are different from the tissue of interest (TI) based on pathophysiology. RESULTS: We developed Phenotype-Tissue Expression and Exploration (PTEE), a tool to facilitate the decision about the most suitable TA for RNA-seq. We integrated phenotype-annotated genes, used 54 tissues from GTEx to perform correlation analyses and identify expressed genes and transcripts between TAs and TIs. We identified skeletal muscle as the most appropriate TA to inquire for cardiac arrhythmia genes and skin as a good proxy to study neurodevelopmental disorders. We also explored RNA-seq limitations and show that on-off switching of gene expression during ontogenesis or circadian rhythm can cause blind spots for RNA-seq-based analyses. CONCLUSIONS: PTEE aids the identification of tissues suitable for RNA-seq for a given pathology to increase the success rate of diagnosis and gene discovery. PTEE is freely available at https://bioinf.eva.mpg.de/PTEE/.


Assuntos
Perfilação da Expressão Gênica , Transcriptoma , Fenótipo , RNA-Seq , Análise de Sequência de RNA
5.
Genet Med ; 23(8): 1492-1497, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33911214

RESUMO

PURPOSE: Genetic diagnostics of neurodevelopmental disorders with epilepsy (NDDE) are predominantly applied in children, thus limited information is available regarding adults or elderly. METHODS: We investigated 150 adult/elderly individuals with NDDE by conventional karyotyping, FMR1 testing, chromosomal microarray, panel sequencing, and for unresolved cases, also by exome sequencing (nsingle = 71, ntrios = 24). RESULTS: We identified (likely) pathogenic variants in 71 cases (47.3%) comprising fragile X syndrome (n = 1), disease-causing copy number (n = 23), and single-nucleotide variants (n = 49). Seven individuals displayed multiple independent genetic diagnoses. The diagnostic yield correlated with the severity of intellectual disability. Individuals with anecdotal evidence of exogenic early-life events (e.g., nuchal cord, complications at delivery) with alleged/unproven association to the disorder had a particularly high yield of 58.3%. Screening for disease-specific comorbidities was indicated in 45.1% and direct treatment consequences arose in 11.8% of diagnosed individuals. CONCLUSION: Panel/exome sequencing displayed the highest yield and should be considered as first-tier diagnostics in NDDE. This high yield and the numerous indications for additional screening or treatment modifications arising from genetic diagnoses indicate a current medical undersupply of genetically undiagnosed adult/elderly individuals with NDDE. Moreover, knowledge of the course of elderly individuals will ultimately help in counseling newly diagnosed individuals with NDDE.


Assuntos
Epilepsia , Deficiência Intelectual , Transtornos do Neurodesenvolvimento , Adulto , Idoso , Epilepsia/diagnóstico , Epilepsia/genética , Proteína do X Frágil da Deficiência Intelectual/genética , Humanos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Cariotipagem , Sequenciamento do Exoma
6.
Proc Natl Acad Sci U S A ; 115(50): 12674-12679, 2018 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-30463942

RESUMO

Understanding large-scale circulations (LSCs) in turbulent convective systems is important for the study of stars, planets, and in many industrial applications. The canonical model of the LSC is quasi-planar with additional horizontal sloshing and torsional modes [Brown E, Ahlers G (2009) J Fluid Mech 638:383-400; Funfschilling D, Ahlers G (2004) Phys Rev Lett 92:194502; Xi HD et al. (2009) Phys Rev Lett 102:044503; Zhou Q et al. (2009) J Fluid Mech 630:367-390]. Using liquid gallium as the working fluid, we show, via coupled laboratory-numerical experiments in tanks with aspect ratios greater than unity ([Formula: see text]), that the LSC takes instead the form of a "jump rope vortex," a strongly 3D mode that periodically orbits around the tank following a motion much like a jump rope on a playground. Further experiments show that this jump rope flow also exists in more viscous fluids such as water, albeit with a far smaller signal. Thus, this jump rope mode is an essential component of the turbulent convection that underlies our observations of natural systems.

7.
Phys Rev Lett ; 124(8): 084505, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32167333

RESUMO

For rapidly rotating turbulent Rayleigh-Bénard convection in a slender cylindrical cell, experiments and direct numerical simulations reveal a boundary zonal flow (BZF) that replaces the classical large-scale circulation. The BZF is located near the vertical side wall and enables enhanced heat transport there. Although the azimuthal velocity of the BZF is cyclonic (in the rotating frame), the temperature is an anticyclonic traveling wave of mode one, whose signature is a bimodal temperature distribution near the radial boundary. The BZF width is found to scale like Ra^{1/4}Ek^{2/3} where the Ekman number Ek decreases with increasing rotation rate.

8.
Brain ; 142(11): 3351-3359, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31504246

RESUMO

Using trio exome sequencing, we identified de novo heterozygous missense variants in PAK1 in four unrelated individuals with intellectual disability, macrocephaly and seizures. PAK1 encodes the p21-activated kinase, a major driver of neuronal development in humans and other organisms. In normal neurons, PAK1 dimers reside in a trans-inhibited conformation, where each autoinhibitory domain covers the kinase domain of the other monomer. Upon GTPase binding via CDC42 or RAC1, the PAK1 dimers dissociate and become activated. All identified variants are located within or close to the autoinhibitory switch domain that is necessary for trans-inhibition of resting PAK1 dimers. Protein modelling supports a model of reduced ability of regular autoinhibition, suggesting a gain of function mechanism for the identified missense variants. Alleviated dissociation into monomers, autophosphorylation and activation of PAK1 influences the actin dynamics of neurite outgrowth. Based on our clinical and genetic data, as well as the role of PAK1 in brain development, we suggest that gain of function pathogenic de novo missense variants in PAK1 lead to moderate-to-severe intellectual disability, macrocephaly caused by the presence of megalencephaly and ventriculomegaly, (febrile) seizures and autism-like behaviour.


Assuntos
Deficiência Intelectual/genética , Megalencefalia/genética , Convulsões/genética , Quinases Ativadas por p21/genética , Actinas/metabolismo , Adolescente , Transtorno Autístico/genética , Criança , Pré-Escolar , Feminino , GTP Fosfo-Hidrolases/metabolismo , Humanos , Deficiência Intelectual/psicologia , Masculino , Megalencefalia/psicologia , Modelos Moleculares , Mutação de Sentido Incorreto/genética , Fosforilação , Convulsões/psicologia , Transdução de Sinais/genética , Sequenciamento do Exoma , Adulto Jovem , Proteína cdc42 de Ligação ao GTP/metabolismo , Quinases Ativadas por p21/química , Proteínas rac1 de Ligação ao GTP/metabolismo
9.
Mod Pathol ; 31(3): 418-428, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29099504

RESUMO

Atypical fibroxanthomas and pleomorphic dermal sarcomas are tumors arising in sun-damaged skin of elderly patients. They have differing prognoses and are currently distinguished using histological criteria, such as invasion of deeper tissue structures, necrosis and lymphovascular or perineural invasion. To investigate the as-yet poorly understood genetics of these tumors, 41 atypical fibroxanthomas and 40 pleomorphic dermal sarcomas were subjected to targeted next-generation sequencing approaches as well as DNA copy number analysis by comparative genomic hybridization. In an analysis of the entire coding region of 341 oncogenes and tumor suppressor genes in 13 atypical fibroxanthomas using an established hybridization-based next-generation sequencing approach, we found that these tumors harbor a large number of mutations. Gene alterations were identified in more than half of the analyzed samples in FAT1, NOTCH1/2, CDKN2A, TP53, and the TERT promoter. The presence of these alterations was verified in 26 atypical fibroxanthoma and 35 pleomorphic dermal sarcoma samples by targeted amplicon-based next-generation sequencing. Similar mutation profiles in FAT1, NOTCH1/2, CDKN2A, TP53, and the TERT promoter were identified in both atypical fibroxanthoma and pleomorphic dermal sarcoma. Activating RAS mutations (G12 and G13) identified in 3 pleomorphic dermal sarcoma were not found in atypical fibroxanthoma. Comprehensive DNA copy number analysis demonstrated a wide array of different copy number gains and losses, with similar profiles in atypical fibroxanthoma and pleomorphic dermal sarcoma. In summary, atypical fibroxanthoma and pleomorphic dermal sarcoma are highly mutated tumors with recurrent mutations in FAT1, NOTCH1/2, CDKN2A, TP53, and the TERT promoter, and a range of DNA copy number alterations. These findings suggest that atypical fibroxanthomas and pleomorphic dermal sarcomas are genetically related, potentially representing two ends of a common tumor spectrum and distinguishing these entities is at present still best performed using histological criteria.


Assuntos
Caderinas/genética , Receptor Notch1/genética , Receptor Notch2/genética , Sarcoma/genética , Neoplasias Cutâneas/genética , Idoso , Idoso de 80 Anos ou mais , Hibridização Genômica Comparativa , Inibidor p16 de Quinase Dependente de Ciclina/genética , Variações do Número de Cópias de DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Regiões Promotoras Genéticas , Telomerase/genética , Proteína Supressora de Tumor p53/genética
10.
Phys Rev Lett ; 120(20): 204502, 2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-29864299

RESUMO

Centrifugal buoyancy affects all rotating turbulent convection phenomena, but is conventionally ignored in rotating convection studies. Here, we include centrifugal buoyancy to investigate what we call Coriolis-centrifugal convection (C^{3}), characterizing two so far unexplored regimes, one where the flow is in quasicyclostrophic balance (QC regime) and another where the flow is in a triple balance between pressure gradient, Coriolis and centrifugal buoyancy forces (CC regime). The transition to centrifugally dominated dynamics occurs when the Froude number Fr equals the radius-to-height aspect ratio γ. Hence, turbulent convection experiments with small γ may encounter centrifugal effects at lower Fr than traditionally expected. Further, we show analytically that the direct effect of centrifugal buoyancy yields a reduction of the Nusselt number Nu. However, indirectly, it can cause a simultaneous increase of the viscous dissipation and thereby Nu through a change of the flow morphology. These direct and indirect effects yield a net Nu suppression in the CC regime and a net Nu enhancement in the QC regime. In addition, we demonstrate that C^{3} may provide a simplified, yet self-consistent, model system for tornadoes, hurricanes, and typhoons.

11.
J Neurooncol ; 127(3): 435-44, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26744134

RESUMO

Melanocytic tumors originating in the central nervous system (MT-CNS) are rare tumors that generally have a favorable prognosis, however malignant tumors do occur. Pathogenetically MT-CNS are not well characterized. Similar to uveal melanoma and blue nevi, they frequently harbor activating GNAQ or GNA11 mutations. Rare NRAS mutations have also been reported. Other mutations have not yet been described. We analyzed 19 MT-CNS, 7 uveal melanomas and 19 cutaneous melanomas using a targeted next generation sequencing approach analyzing 29 genes known to be frequently mutated in other melanocytic tumors (in particular uveal and cutaneous melanomas). In concordance with previous studies, cutaneous melanoma samples showed frequent NRAS or BRAF mutations, as well as mutations in other genes (e.g. NF1, RAC1, PIK3CA, ARID1A). Metastasized uveal melanomas exhibited mutations in GNAQ, GNA11 and BAP1. In contrast, MT-CNS almost exclusively demonstrated mutations in GNAQ (71 %) or GNA11 (12 %). Interestingly both GNA11 mutations identified were detected in MT-CNS diagnosed as intermediate grade melanocytomas which also recurred. One of these recurrent cases also harbored an inactivating BAP1 mutation and was found to have lost one copy of chromosome 3. Our findings show that while MT-CNS do have GNAQ or GNA11 mutations, they rarely harbor other recurrent mutations found in uveal or cutaneous melanomas. Considering chromosome 3 and BAP1 loss are robust markers of poor prognosis in uveal melanoma, it will prove interesting to determine whether these genomic alterations are also of prognostic significance in MT-CNS.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias do Sistema Nervoso Central/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Melanoma/genética , Mutação/genética , Recidiva Local de Neoplasia/genética , Adolescente , Adulto , Idoso , Neoplasias do Sistema Nervoso Central/patologia , Variações do Número de Cópias de DNA , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Masculino , Melanoma/patologia , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/patologia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Adulto Jovem
12.
Phys Rev Lett ; 114(11): 114302, 2015 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-25839274

RESUMO

We report a new thermal boundary layer equation for turbulent Rayleigh-Bénard convection for Prandtl number Pr>1 that takes into account the effect of turbulent fluctuations. These fluctuations are neglected in existing equations, which are based on steady-state and laminar assumptions. Using this new equation, we derive analytically the mean temperature profiles in two limits: (a) Pr≳1 and (b) Pr≫1. These two theoretical predictions are in excellent agreement with the results of our direct numerical simulations for Pr=4.38 (water) and Pr=2547.9 (glycerol), respectively.

13.
Mol Ecol ; 23(7): 1717-29, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24795996

RESUMO

After centuries of human hunting, the Eurasian beaver Castor fiber had disappeared from most of its original range by the end of the 19th century. The surviving relict populations are characterized by both low genetic diversity and strong phylogeographical structure. However, it remains unclear whether these attributes are the result of a human-induced, late Holocene bottleneck or already existed prior to this reduction in range. To investigate genetic diversity in Eurasian beaver populations during the Holocene, we obtained mitochondrial control region DNA sequences from 48 ancient beaver samples and added 152 modern sequences from GenBank. Phylogeographical analyses of the data indicate a differentiation of European beaver populations into three mitochondrial clades. The two main clades occur in western and eastern Europe, respectively, with an early Holocene contact zone in eastern Europe near a present-day contact zone. A divergent and previously unknown clade of beavers from the Danube Basin survived until at least 6000 years ago, but went extinct during the transition to modern times. Finally, we identify a recent decline in effective population size of Eurasian beavers, with a stronger bottleneck signal in the western than in the eastern clade. Our results suggest that the low genetic diversity and the strong phylogeographical structure in recent beavers are artefacts of human hunting-associated population reductions. While beaver populations have been growing rapidly since the late 19th century, genetic diversity within modern beaver populations remains considerably reduced compared to what was present prior to the period of human hunting and habitat reduction.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Genética Populacional , Roedores/genética , Animais , Teorema de Bayes , Europa (Continente) , Extinção Biológica , Fósseis , Modelos Genéticos , Hibridização de Ácido Nucleico , Filogenia , Filogeografia , Análise de Sequência de DNA
14.
Matrix Biol ; 128: 1-10, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38378098

RESUMO

The extracellular matrix (ECM) is a network of macromolecules that presents a vital scaffold for cells and enables multiple ways of cellular communication. Thus, it is essential for many physiological processes such as development, tissue morphogenesis, homeostasis, the shape and partially the size of the body and its organs. To ensure these, the composition of the ECM is tissue-specific and highly dynamic. ECM homeostasis is therefore tightly controlled by several mechanisms. Here, we show that FMI-1, the homolog of the Adhesion GPCR Flamingo/CELSR/ADGRC in the nematode Caenorhabditis elegans, modulates the composition of the ECM by controlling the production both of ECM molecules such as collagens and also of ECM modifying enzymes. Thereby, FMI-1 affects the morphology and functionality of the nematode´s cuticle, which is mainly composed of ECM, and also modulates the body size. Mechanistic analyses highlight the fact that FMI-1 exerts its function from neurons non-cell autonomously (trans) solely via its extracellular N terminus. Our data support a model, by which the activity of the receptor, which has a well-described role in the planar cell polarity (PCP) pathway, involves the PCP molecule VANG-1, but seems to be independent of the DBL-1/BMP pathway.


Assuntos
Caderinas , Proteínas de Caenorhabditis elegans , Animais , Tamanho Corporal , Caderinas/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/fisiologia , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Comunicação Celular , Matriz Extracelular/metabolismo
15.
Signal Transduct Target Ther ; 9(1): 103, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38664368

RESUMO

Obesity is one of the diseases with severe health consequences and rapidly increasing worldwide prevalence. Understanding the complex network of food intake and energy balance regulation is an essential prerequisite for pharmacological intervention with obesity. G protein-coupled receptors (GPCRs) are among the main modulators of metabolism and energy balance. They, for instance, regulate appetite and satiety in certain hypothalamic neurons, as well as glucose and lipid metabolism and hormone secretion from adipocytes. Mutations in some GPCRs, such as the melanocortin receptor type 4 (MC4R), have been associated with early-onset obesity. Here, we identified the adhesion GPCR latrophilin 1 (ADGRL1/LPHN1) as a member of the regulating network governing food intake and the maintenance of energy balance. Deficiency of the highly conserved receptor in mice results in increased food consumption and severe obesity, accompanied by dysregulation of glucose homeostasis. Consistently, we identified a partially inactivating mutation in human ADGRL1/LPHN1 in a patient suffering from obesity. Therefore, we propose that LPHN1 dysfunction is a risk factor for obesity development.


Assuntos
Obesidade , Receptores Acoplados a Proteínas G , Receptores de Peptídeos , Animais , Humanos , Camundongos , Metabolismo Energético/genética , Glucose/metabolismo , Glucose/genética , Obesidade/genética , Obesidade/metabolismo , Obesidade/patologia , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo
16.
Oncotarget ; 14: 14-20, 2023 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-36634214

RESUMO

Overexpression of the dihydrolipoamide S-succinyltransferase (DLST) is associated with poor outcome in neuroblastoma patients and triple-negative breast cancer (TNBC) and specifically with the oxidative phosphorylation (OXPHOS) pathway. Inhibitors of OXPHOS were previously suggested as a potential therapeutic strategy for a subset of patients with high-risk neuroblastoma. Here, we tested if cell lines with DLST amplifications or high mRNA levels were associated with sensitivity to 250 drugs from the Genomics of Drug Sensitivity in Cancer (GDSC) dataset by comparing them to cell lines without these changes. DLST-altered cell lines were more sensitive to 7 approved drugs, among these obatoclax mesylate, a BCL2 inhibitor that reduces OXPHOS in human leukemia stem cells. Moreover, several protein kinase inhibitors were identified to be efficient in cell lines with DLST amplifications or high mRNA levels, suggesting a vulnerability of DLST-altered cell lines for drugs targeting the ERK/MAPK pathway. Furthermore, increased DLST expression in cell lines with driver mutations in KRAS supported this relationship. We therefore conclude that, in addition to OXPHOS, protein kinases could be potential targets of therapy in the presence of DLST amplifications or high mRNA levels. The new drug candidates proposed here could serve in experimental testing on drug efficacy in knock-in cell lines and DLST-activated tumors.


Assuntos
Neuroblastoma , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Linhagem Celular , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , Linhagem Celular Tumoral
17.
Cancers (Basel) ; 15(3)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36765660

RESUMO

Although adjuvant therapies with immune checkpoint inhibitors (ICI) and BRAF/MEK inhibitors improve recurrence-free survival (RFS) in stage III melanoma patients significantly, prognostic factors are needed to identify patients with a high risk of disease recurrence. Therefore, the aim of our study was to investigate the prognostic potential of routinely collected blood parameters for stage III melanoma patients with microscopic sentinel lymph node (SLN) metastasis. Altogether, we retrospectively analyzed 138 stage III melanoma patients who were diagnosed with microscopic SLN metastasis at the skin cancer center of the University Hospital Cologne between 2011 and 2020 and who did not receive prior adjuvant therapy with ICI or BRAF/MEK-inhibitors. Univariate and multivariate Cox regression analyses, Kaplan-Meier survival analyses and receiver operating characteristic (ROC) curves were performed to assess the impact of preoperatively collected blood parameters and blood ratios on recurrence-free survival (RFS; primary endpoint) and overall survival (OS). A high neutrophil-to-lymphocyte ratio (NLR), low lymphocyte-to-monocyte ratio (LMR) and high C-reactive protein (CRP) value were significantly associated with shorter RFS in multivariate analysis. For LMR (cut-off 3.5) and for CRP (cut-off 3.0) this effect remained after dichotomization. CRP showed a stronger association with RFS than NLR or LMR, with the highest association being detected for the combination of low LMR and high CRP. Additionally, derived NLR ≥ 2.0 was significantly associated with shorter OS in multivariate analysis. In summary, our data suggest that CRP in combination with LMR should be considered as a marker for melanoma recurrence in stage III melanoma patients with microscopic SLN metastasis.

18.
J Cancer Res Clin Oncol ; 149(9): 5539-5545, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36472769

RESUMO

PURPOSE: A wide therapeutic repertoire has become available to oncologists including radio- and chemotherapy, small molecules and monoclonal antibodies. However, drug efficacy can be limited by genetic heterogeneity. Here, we designed a webtool that facilitates the data analysis of the in vitro drug sensitivity data on 265 approved compounds from the GDSC database in association with a plethora of genetic changes documented for 1001 cell lines in the CCLE data. METHODS: The webtool computes odds ratios of drug resistance for a queried set of genetic alterations. It provides results on the efficacy of single compounds or groups of compounds assigned to cellular signaling pathways. Webtool availability: https://tools.hornlab.org/GDSC/ . RESULTS: We first replicated established associations of genetic driver mutations in BRAF, RAS genes and EGFR with drug response. We then tested the 'BRCAness' hypothesis and did not find increased sensitivity to the assayed PARP inhibitors. Analyzing specific PIK3CA mutations related to cancer and mendelian overgrowth, we found support for the described sensitivity of H1047 mutants to GSK690693 targeting the AKT pathway. Testing a co-mutated gene pair, GATA3 activation abolished PTEN-related sensitivity to PI3K/mTOR inhibition. Finally, the pharmacogenomic modifier ABCB1 was associated with olaparib resistance. CONCLUSIONS: This tool could identify potential drug candidates in the presence of custom sets of genetic changes and moreover, improve the understanding of signaling pathways. The underlying computer code can be adapted to larger drug response datasets to help structure and accommodate the increasingly large biomedical knowledge base.


Assuntos
Neoplasias , Fosfatidilinositol 3-Quinases , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Transdução de Sinais , Mutação , Linhagem Celular , Resistência a Medicamentos , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral
19.
PLoS One ; 18(7): e0281487, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37418389

RESUMO

Telomerase reverse transcriptase (TERT) promoter mutations occur frequently in cancer, have been associated with increased TERT expression and cell proliferation, and could potentially influence therapeutic regimens for melanoma. As the role of TERT expression in malignant melanoma and the non-canonical functions of TERT remain understudied, we aimed to extend the current knowledge on the impact of TERT promoter mutations and expression alterations in tumor progression by analyzing several highly annotated melanoma cohorts. Using multivariate models, we found no consistent association for TERT promoter mutations or TERT expression with the survival rate in melanoma cohorts under immune checkpoint inhibition. However, the presence of CD4+ T cells increased with TERT expression and correlated with the expression of exhaustion markers. While the frequency of promoter mutations did not change with Breslow thickness, TERT expression was increased in metastases arising from thinner primaries. As single-cell RNA-sequencing (RNA-seq) showed that TERT expression was associated with genes involved in cell migration and dynamics of the extracellular matrix, this suggests a role of TERT during invasion and metastasis. Co-regulated genes found in several bulk tumors and single-cell RNA-seq cohorts also indicated non-canonical functions of TERT related to mitochondrial DNA stability and nuclear DNA repair. This pattern was also evident in glioblastoma and across other entities. Hence, our study adds to the role of TERT expression in cancer metastasis and potentially also immune resistance.


Assuntos
Melanoma , Neoplasias Cutâneas , Telomerase , Humanos , Linfócitos T CD4-Positivos/patologia , Melanoma/genética , Melanoma/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Regiões Promotoras Genéticas , Mutação , Reparo do DNA/genética , Telomerase/genética
20.
Pigment Cell Melanoma Res ; 36(2): 252-258, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36382970

RESUMO

Large genome-scale studies are deposited in various public sequence repositories. However, their access and analysis can be non-trivial to infrequent users. Here, we present a new database connecting whole transcriptomes with clinical data for straight-forward access and analysis of patient-specific samples. Users can perform association tests of survival and gene expression across different cohorts, identify cell-type expressions, or correlate the presence of immune cells. In summary, we present a new data hub for bench scientists to perform replication and discovery studies.


Assuntos
Melanoma , Humanos , Transcriptoma
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