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1.
Diagn Pathol ; 19(1): 9, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184614

RESUMO

Deleterious mutations in the BRCA1 and BRCA2 genes have significant therapeutic relevance in clinical settings regarding personalized therapy approaches. BRCA1 and BRCA2 play a pivotal role in homologous recombination (HR) and thus are sensitive for PARP inhibitors (PARPi). Beyond the narrow scope of evaluating only the BRCA mutation status, PARPi can be beneficial for HR deficient (HRD) patients, who harbor mutations in other HR-associated genes. In the present retrospective study, a novel targeted HRD gene panel was validated and implemented for use with FFPE tissue. Samples of patients with ovarian, breast, pancreatic and prostate cancer were included. Variants were robustly detected with various DNA input amounts and the use of test samples showed complete concordance between previously known mutations and HRD panel results. From all the 90 samples included in this cohort, TP53 was the most frequently altered gene (73%). Deleterious BRCA1/2 mutations were found in 20 (22%) of all samples. New pathogenic or likely pathogenic mutations in additional HR-associated genes were identified in 22 (24%) patients. Taken together, the present study proves the feasibility of a new HRD gene panel with reliable panel performance and offers the possibility to easily screen for resistance mutations acquired over treatment time.Mutations in HR-associated genes, besides BRCA1/2, might represent promising potential targets for synthetic lethality approaches. Thus, a substantial number of patients may benefit from expanding the scope of therapeutic agents like PARPi.


Assuntos
Proteína BRCA1 , Proteína BRCA2 , Masculino , Humanos , Proteína BRCA1/genética , Proteína BRCA2/genética , Estudos Retrospectivos , Mutação , Recombinação Homóloga
2.
RSC Adv ; 13(33): 22777-22788, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37520102

RESUMO

Nitrogen-containing porous carbons prepared by the pyrolysis of adequate biopolymer-based precursors have shown potential in several electrochemical energy-related applications. However, it is still of crucial interest to find the optimal precursors and process conditions which would allow the preparation of carbons with adequate porous structure as well as suitable nitrogen content and distribution of functional groups. In the present work we suggested a straightforward approach to prepare N-doped porous carbons by direct pyrolysis under nitrogen of chitosan : coffee blends of different compositions and using KOH for simultaneous surface activation. The synthetized carbon materials were tested for the electrochemical oxygen reduction to hydrogen peroxide (H2O2). A higher fraction of chitosan in the precursor led to a decrease in meso- and nano-porosity of the formed porous carbons, while their activity towards H2O2 generation increased. The nitrogen species derived from chitosan seem to play a very important role. Out of the synthesized catalysts the one with the largest content of pyridinic nitrogen sites exhibited the highest faradaic efficiency. The faradaic efficiencies and current densities of the synthesized materials were comparable with the ones of other commercially available carbons obtained from less renewable precursors.

3.
BJS Open ; 7(3)2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37146205

RESUMO

BACKGROUND: Currently, treatment recommendations for papillary thyroid carcinoma are not based on the genetic background causing tumourigenesis. The aim of the present study was to correlate the mutational profile of papillary thyroid carcinoma with clinical parameters of tumour aggressiveness, to establish recommendations for risk-stratified surgical treatment. METHOD: Papillary thyroid carcinoma tumour tissue of patients undergoing thyroid surgery at the University Medical Centre Mainz underwent analysis of BRAF, TERT promoter and RAS mutational status as well as potential RET and NTRK rearrangements. Mutation status was correlated with clinical course of disease. RESULTS: One hundred and seventy-one patients operated for papillary thyroid carcinoma were included. The median age was 48 years (range 8-85) and 69 per cent (118/171) of patients were females. One hundred and nine papillary thyroid carcinomas were BRAF-V600E mutant, 16 TERT promotor mutant and 12 RAS mutant; 12 papillary thyroid carcinomas harboured RET rearrangements and two papillary thyroid carcinomas showed NTRK rearrangements. TERT promoter mutant papillary thyroid carcinomas had a higher risk of distant metastasis (OR 51.3, 7.0 to 1048.2, P < 0.001) and radioiodine-refractory disease (OR 37.8, 9.9 to 169.5, P < 0.001). Concomitant BRAF and TERT promoter mutations increased the risk of radioiodine-refractory disease in papillary thyroid carcinoma (OR 21.7, 5.6 to 88.9, P < 0.001). RET rearrangements were associated with a higher count of tumour-affected lymph nodes (OR 7950.9, 233.7 to 270495.7, P < 0.001) but did not influence distant metastasis or radioiodine-refractory disease. CONCLUSIONS: Papillary thyroid carcinoma with concomitant BRAF-V600E and TERT promoter mutations demonstrated an aggressive course of disease, suggesting the need for a more extensive surgical strategy. RET rearrangement-positive papillary thyroid carcinoma did not affect the clinical outcome, potentially obviating the need for prophylactic lymphadenectomy.


Assuntos
Carcinoma Papilar , Carcinoma , Telomerase , Neoplasias da Glândula Tireoide , Feminino , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Masculino , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/cirurgia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Carcinoma/patologia , Carcinoma Papilar/genética , Carcinoma Papilar/cirurgia , Proteínas Proto-Oncogênicas B-raf/genética , Radioisótopos do Iodo , Telomerase/genética , Medição de Risco
4.
Cells ; 12(9)2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37174657

RESUMO

Primary liver cancer is the third leading cause of cancer-related death worldwide. An increasing body of evidence suggests that the Hippo tumor suppressor pathway plays a critical role in restricting cell proliferation and determining cell fate during physiological and pathological processes in the liver. Merlin (Moesin-Ezrin-Radixin-like protein) encoded by the NF2 (neurofibromatosis type 2) gene is an upstream regulator of the Hippo signaling pathway. Targeting of Merlin to the plasma membrane seems to be crucial for its major tumor-suppressive functions; this is facilitated by interactions with membrane-associated proteins, including CD44 (cluster of differentiation 44). Mutations within the CD44-binding domain of Merlin have been reported in many human cancers. This study evaluated the relative contribution of CD44- and Merlin-dependent processes to the development and progression of liver tumors. To this end, mice with a liver-specific deletion of the Nf2 gene were crossed with Cd44-knockout mice and subjected to extensive histological, biochemical and molecular analyses. In addition, cells were isolated from mutant livers and analyzed by in vitro assays. Deletion of Nf2 in the liver led to substantial liver enlargement and generation of hepatocellular carcinomas (HCCs), intrahepatic cholangiocarcinomas (iCCAs), as well as mixed hepatocellular cholangiocarcinomas. Whilst deletion of Cd44 had no influence on liver size or primary liver tumor development, it significantly inhibited metastasis formation in Nf2-mutant mice. CD44 upregulates expression of integrin ß2 and promotes transendothelial migration of liver cancer cells, which may facilitate metastatic spreading. Overall, our results suggest that CD44 may be a promising target for intervening with metastatic spreading of liver cancer.


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Receptores de Hialuronatos , Neoplasias Hepáticas , Neurofibromatose 2 , Animais , Humanos , Camundongos , Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos , Carcinoma Hepatocelular/genética , Colangiocarcinoma/genética , Genes da Neurofibromatose 2 , Receptores de Hialuronatos/genética , Neoplasias Hepáticas/genética , Neurofibromatose 2/genética , Neurofibromina 2/genética , Neurofibromina 2/metabolismo
5.
Int J Mol Sci ; 23(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35955749

RESUMO

Osteosarcoma is the most common type of pediatric bone tumor. Despite great advances in chemotherapy during the past decades, the survival rates of osteosarcoma patients remain unsatisfactory. Drug resistance is one of the main reasons, leading to treatment failure and poor prognosis. Previous reports correlated expression of cluster of differentiation 44 (CD44) with drug resistance and poor survival of osteosarcoma patients, however the underlying mechanisms are poorly defined. Here, we investigated the role of CD44 in the regulation of drug chemoresistance, using osteosarcoma cells isolated from mice carrying a mutation of the tumor suppressor neurofibromatosis type 2 (Nf2) gene. CD44 expression was knocked-down in the cells using CRISPR/Cas9 approach. Subsequently, CD44 isoforms and mutants were re-introduced to investigate CD44-dependent processes. Sensitivity to doxorubicin was analyzed in the osteosarcoma cells with modified CD44 expression by immunoblot, colony formation- and WST-1 assay. To dissect the molecular alterations induced by deletion of Cd44, RNA sequencing was performed on Cd44-positive and Cd44-negative primary osteosarcoma tissues isolated from Nf2-mutant mice. Subsequently, expression of candidate genes was evaluated by quantitative reverse transcription PCR (qRT-PCR). Our results indicate that CD44 increases the resistance of osteosarcoma cells to doxorubicin by up-regulating the levels of multidrug resistance (MDR) 1 protein expression, and suggest the role of proteolytically released CD44 intracellular domain, and hyaluronan interactions in this process. Moreover, high throughput sequencing analysis identified differential regulation of several apoptosis-related genes in Cd44-positive and -negative primary osteosarcomas, including p53 apoptosis effector related to PMP-22 (Perp). Deletion of Cd44 in osteosarcoma cells led to doxorubicin-dependent p53 activation and a profound increase in Perp mRNA expression. Overall, our results suggest that CD44 might be an important regulator of drug resistance and suggest that targeting CD44 can sensitize osteosarcoma to standard chemotherapy.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Camundongos , Osteossarcoma/tratamento farmacológico , Osteossarcoma/genética , Osteossarcoma/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
6.
Cells ; 12(1)2022 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-36611868

RESUMO

The single nucleotide polymorphism I148M of the lipase patatin-like phospholipase domain containing 3 (PNPLA3) is associated with an unfavorable prognosis in alcoholic and non-alcoholic steatohepatitis (ASH, NASH), with progression to liver cirrhosis and development of hepatocellular carcinoma. In this study, we investigated the mechanistic interaction of PNPLA3 with lipid droplet (LD)-associated proteins of the perilipin family, which serve as gatekeepers for LD degradation. In a collective of 106 NASH, ASH and control liver samples, immunohistochemical analyses revealed increased ballooning, inflammation and fibrosis, as well as an accumulation of PNPLA3-perilipin 5 complexes on larger LDs in patients homo- and heterozygous for PNPLA3(I148M). Co-immunoprecipitation demonstrated an interaction of PNPLA3 with perilipin 5 and the key enzyme of lipolysis, adipose triglyceride lipase (ATGL). Localization studies in cell cultures and human liver showed colocalization of perilipin 5, ATGL and PNPLA3. Moreover, the lipolytic activity of ATGL was negatively regulated by PNPLA3 and perilipin 5, whereas perilipin 1 displaced PNPLA3 from the ATGL complex. Furthermore, ballooned hepatocytes, the hallmark of steatohepatitis, were positive for PNPLA3 and perilipins 2 and 5, but showed decreased perilipin 1 expression with respect to neighboured hepatocytes. In summary, PNPLA3- and ATGL-driven lipolysis is significantly regulated by perilipin 1 and 5 in steatohepatitis.


Assuntos
Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Lipólise , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Perilipina-1 , Perilipina-5
7.
Biomedicines ; 9(10)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34680427

RESUMO

Neurodegenerative diseases, including Alzheimer's (AD) and Parkinson's diseases (PD), are complex heterogeneous diseases with highly variable patient responses to treatment. Due to the growing evidence for ageing-related clinical and pathological commonalities between AD and PD, these diseases have recently been studied in tandem. In this study, we analysed transcriptomic data from AD and PD patients, and stratified these patients into three subclasses with distinct gene expression and metabolic profiles. Through integrating transcriptomic data with a genome-scale metabolic model and validating our findings by network exploration and co-analysis using a zebrafish ageing model, we identified retinoids as a key ageing-related feature in all subclasses of AD and PD. We also demonstrated that the dysregulation of androgen metabolism by three different independent mechanisms is a source of heterogeneity in AD and PD. Taken together, our work highlights the need for stratification of AD/PD patients and development of personalised and precision medicine approaches based on the detailed characterisation of these subclasses.

8.
Chemistry ; 27(68): 17127-17144, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34633707

RESUMO

Perovskites are interesting oxidation catalysts due to their chemical flexibility enabling the tuning of several properties. In this work, we synthesized LaFe1-x Cox O3 catalysts by co-precipitation and thermal decomposition, characterized them thoroughly and studied their 2-propanol oxidation activity under dry and wet conditions to bridge the knowledge gap between gas and liquid phase reactions. Transient tests showed a highly active, unstable low-temperature (LT) reaction channel in conversion profiles and a stable, less-active high-temperature (HT) channel. Cobalt incorporation had a positive effect on the activity. The effect of water was negative on the LT channel, whereas the HT channel activity was boosted for x>0.15. The boost may originate from a slower deactivation rate of the Co3+ sites under wet conditions and a higher amount of hydroxide species on the surface comparing wet to dry feeds. Water addition resulted in a slower deactivation for Co-rich catalysts and higher activity in the HT channel state.

9.
Sci Rep ; 11(1): 16745, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34408162

RESUMO

The current standard for molecular profiling of colorectal cancer (CRC) is using resected or biopsied tissue specimens. However, they are limited regarding sampling frequency, representation of tumor heterogeneity, and sampling can expose patients to adverse side effects. The analysis of cell-free DNA (cfDNA) from blood plasma, which is part of a liquid biopsy, is minimally invasive and in principle enables detection of all tumor-specific mutations. Here, we analyzed cfDNA originating from nucleus and mitochondria and investigated their characteristics and mutation status in a cohort of 18 CRC patients and 10 healthy controls using targeted next-generation sequencing (NGS) and digital PCR. Longitudinal analyses of nuclear cfDNA level and size during chemotherapy revealed a decreasing cfDNA content and a shift from short to long fragments, indicating an appropriate therapy response, while shortened cfDNAs and increased cfDNA content corresponded with tumor recurrence. Comparative NGS analysis of nuclear tissue and plasma DNA demonstrated a good patient-level concordance and cfDNA revealed additional variants in three of the cases. Analysis of mitochondrial cfDNA surprisingly revealed a higher plasma copy number in healthy subjects than in CRC patients. These results highlight the potential clinical utility of liquid biopsies in routine diagnostics and surveillance of CRC patients as complementation to tissue biopsies or as an attractive alternative in cases where tissue biopsies are risky or the quantity/quality does not allow testing.


Assuntos
Neoplasias Colorretais/genética , DNA Mitocondrial/genética , DNA de Neoplasias/genética , Sequenciamento de Nucleotídeos em Larga Escala , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/patologia , Feminino , Humanos , Biópsia Líquida , Masculino , Pessoa de Meia-Idade
10.
ACS Nano ; 15(4): 7421-7429, 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33759515

RESUMO

Like other 2D materials, the boron-based borophene exhibits interesting structural and electronic properties. While borophene is typically prepared by molecular beam epitaxy, we report here on an alternative way of synthesizing large single-phase borophene domains by segregation-enhanced epitaxy. X-ray photoelectron spectroscopy shows that borazine dosing at 1100 °C onto Ir(111) yields a boron-rich surface without traces of nitrogen. At high temperatures, the borazine thermally decomposes, nitrogen desorbs, and boron diffuses into the substrate. Using time-of-flight secondary ion mass spectrometry, we show that during cooldown the subsurface boron segregates back to the surface where it forms borophene. In this case, electron diffraction reveals a (6 × 2) reconstructed borophene χ6-polymorph, and scanning tunneling spectroscopy suggests a Dirac-like behavior. Studying the kinetics of borophene formation in low energy electron microscopy shows that surface steps are bunched during the borophene formation, resulting in elongated and extended borophene domains with exceptional structural order.

11.
Int J Cancer ; 147(9): 2564-2577, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32525563

RESUMO

Merlin is a versatile tumor suppressor protein encoded by the NF2 gene. Several lines of evidence suggest that Merlin exerts its tumor suppressor activity, at least in part, by forming an inhibitory complex with cluster of differentiation 44 (CD44). Consistently, numerous NF2 mutations in cancer patients are predicted to perturb the interaction of Merlin with CD44. We hypothesized that disruption of the Merlin-CD44 complex through loss of Merlin, unleashes putative tumor- or metastasis-promoting functions of CD44. To evaluate the relevance of the Merlin-CD44 interaction in vivo, we compared tumor growth and progression in Cd44-positive and Cd44-negative Nf2-mutant mice. Heterozygous Nf2-mutant mice were prone to developing highly metastatic osteosarcomas. Importantly, while the absence of the Cd44 gene had no effect on the frequency of primary osteosarcoma development, it strongly diminished osteosarcoma metastasis formation in the Nf2-mutant mice. In vitro assays identified transendothelial migration as the most prominent cellular phenotype dependent on CD44. Adhesion to endothelial cells was blocked by interfering with integrin α4ß1 (very late antigen-4, VLA-4) on osteosarcoma cells and CD44 upregulated levels of integrin VLA-4 ß1 subunit. Among other putative functions of CD44, which may contribute to the metastatic behavior, the passage through the endothelial cells also appears to be critical in vivo, as CD44 significantly promoted formation of lung metastasis upon intravenous injection of osteosarcoma cells into immunocompromised mice. Altogether, our results strongly suggest that CD44 plays a metastasis-promoting role in the absence of Merlin.


Assuntos
Neoplasias Ósseas/genética , Receptores de Hialuronatos/metabolismo , Neoplasias Pulmonares/genética , Neurofibromina 2/genética , Osteossarcoma/genética , Animais , Neoplasias Ósseas/patologia , Osso e Ossos/patologia , Adesão Celular/genética , Linhagem Celular Tumoral/transplante , Proliferação de Células/genética , Modelos Animais de Doenças , Progressão da Doença , Humanos , Receptores de Hialuronatos/genética , Pulmão/patologia , Neoplasias Pulmonares/secundário , Masculino , Camundongos , Camundongos Knockout , Osteossarcoma/secundário
12.
Cancer Genet ; 238: 10-17, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31425920

RESUMO

BACKGROUND: Rearrangements of RET are drivers of oncogenesis, traceable in different cancer types as papillary thyroid carcinoma (PTC), non-small cell lung cancer, colorectal or breast cancer. Anchored multiplex PCR based next-generation sequencing (NGS) can detect RET rearrangements involving previously unknown partner genes. METHODS: A sample of PTC underwent NGS, following detection of RET rearrangement by fluorescence in situ hybridization. Expression analysis of ANKRD26 and RET was performed for the tumor harboring ANKRD26-RET, for corresponding normal thyroid tissue and PTC tumors with representative genetic alterations (BRAFV600E, CCDC6-RET), complemented by a comparative search in the "UniProt" database. RESULTS: NGS analysis resulted in the discovery of the fusion ANKRD26-RET. ANKRD26 mRNA was expressed in all PTC tumors (ANKRD26-RET, BRAFV600E, CCDC6-RET) and in normal thyroid tissue, whereas RET mRNA was detected only in the tumors with RET rearrangement. On protein level, ANKRD26-RET combines the RET tyrosine kinase to ankyrin repeat and coiled-coil domains. CONCLUSIONS: ANKRD26-RET is a novel rearrangement of the RET gene, associated with RET expression in thyroid tissue. The result is a fusion of the RET tyrosine kinase to prominent protein-protein interaction motifs. Further studies are required to investigate the influence of different RET rearrangements on metastasis and disease-free survival in PTC.


Assuntos
Fusão Gênica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas Proto-Oncogênicas c-ret/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Análise de Sobrevida
13.
Nat Commun ; 10(1): 2459, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31150008

RESUMO

The original version of this Article contained an error in the spelling of the author Jule Müller, which was incorrectly given as Julia Müller. Additionally, in Fig. 4a, the blue-red colour scale for fold change in ageing/disease regulation included a blue stripe in place of a red stripe at the right-hand end of the scale. These errors have been corrected in both the PDF and HTML versions of the Article.

14.
BMC Gastroenterol ; 19(1): 21, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30717682

RESUMO

BACKGROUND: Carcinomas of the small bowel are rare tumors usually with dismal prognosis. Most recently, some potentially treatable molecular alterations were described. We emphasize the growing evidence of individualized treatment options in small bowel carcinoma. METHODS: We performed a DNA- based multi-gene panel using ultra-deep sequencing analysis (including 14 genes with up to 452 amplicons in total; KRAS, NRAS, HRAS, BRAF, DDR2, ERBB2, KEAP1, NFE2L2, PIK3CA, PTEN, RHOA, BRCA1, BRCA2 and TP53) as well as an RNA-based gene fusion panel including ALK, BRAF, FGFR1, FGFR2, FGFR3, MET, NRG1, NTRK1, NTRK2, NTRK3, RET and ROS1 on eleven formalin fixed and paraffin embedded small bowel carcinomas. Additionally, mismatch-repair-deficiency was analyzed by checking the microsatellite status using the five different mononucleotide markers BAT25, BAT26, NR-21, NR-22 and NR-27 and loss of mismatch repair proteins using four different markers (MLH1, MSH6, MSH2, PMS2). RESULTS: In five out of eleven small bowel carcinomas we found potentially treatable genetic alterations. Three patients demonstrated pathogenic (class 5) BRCA1 or BRCA2 mutations - one germline-related in a mixed neuroendocrine-non neuroendocrine neoplasm (MiNEN). Two additional patients revealed an activating ERBB2 mutation or PIK3CA mutation. Furthermore two tumors were highly microsatellite-instable (MSI-high), in one case associated to Lynch-syndrome. We did not find any gene fusions. CONCLUSION: Our results underscore, in particular, the relevance of potentially treatable molecular alterations (like ERBB2, BRCA and MSI) in small bowel carcinomas. Further studies are needed to proof the efficacy of these targeted therapies in small bowel carcinomas.


Assuntos
Adenocarcinoma/terapia , Proteína BRCA2/genética , Neoplasias Intestinais/terapia , Intestino Delgado , Instabilidade de Microssatélites , Medicina de Precisão , Receptor ErbB-2/genética , Ubiquitina-Proteína Ligases/genética , Adenocarcinoma/genética , Idoso , Reparo do DNA/genética , Humanos , Neoplasias Intestinais/genética , Pessoa de Meia-Idade , Mutação
15.
Cancer Genet ; 230: 13-20, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30466862

RESUMO

BACKGROUND: In the field of gene fusions driving tumorigenesis in papillary thyroid carcinoma (PTC), rearrangement of the proto-oncogene RET is the most frequent alteration. Apart from the most common rearrangement of RET to CCDC6, more than 15 partner genes are yet reported. The landscape of RET rearrangements in PTC ("RET-PTC") can notably be enlarged by modern targeted next-generation sequencing, indicating similarities between oncogenic pathways in other cancer types with identical genetic alterations. METHODS: Targeted next-generation sequencing was performed for two cases of BRAF-wild type PTC with confirmation of the results by Sanger sequencing. A "UniProt" database research was performed to assess protein alterations resulting from RET rearrangements. RESULTS: RUFY2-RET and KIAA1468-RET were detected. The fusion genes were not present in normal tissue of the index patients. The rearrangement RUFY2-RET lead to a fusion of the RET tyrosine kinase domain to a RUN domain and a coiled-coil domain. For KIAA1468-RET, a fusion to a LisH domain and two coiled-coil domains resulted. CONCLUSIONS: RUFY2-RET and KIAA1468-RET are novel RET/PTC rearrangements. The fusions were previously described in non-small cell lung cancer. The rearrangement results in a fusion of the RET tyrosine kinase to regulatory domains of RUFY2 and KIAA1468.


Assuntos
Proteínas de Fusão Oncogênica/genética , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas c-ret/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Adulto , Proteínas de Transporte/genética , Feminino , Rearranjo Gênico , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Proteínas Nucleares , Proto-Oncogene Mas
16.
Int J Cancer ; 144(11): 2782-2794, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30485423

RESUMO

Primary liver cancer (PLC) ranks among the most lethal solid cancers worldwide due to lack of effective biomarkers for early detection and limited treatment options in advanced stages. Development of primary culture models that closely recapitulate phenotypic and molecular diversities of PLC is urgently needed to improve the patient outcome. Long-term cultures of 7 primary liver cancer cell lines of hepatocellular and cholangiocellular origin were established using defined culture conditions. Morphological and histological characteristics of obtained cell lines and xenograft tumors were analyzed and compared to original tumors. Time course analyses of transcriptomic and genomic changes were performed using next-generation sequencing (NGS). Key oncogenic alterations were identified by targeted NGS and cell lines carrying potentially actionable mutations were treated with corresponding specific inhibitors. PDCL fully resembled morphological features of the primary cancers in vitro and in vivo over extended period in culture. Genomic alterations as well as transcriptome profiles showed high similarity with primary tumors and remained stable during long-term culturing. Targeted-NGS confirmed that key oncogenic mutations such as TP53, KRAS, CTNNB1 as well as actionable mutations (e.g. MET, cKIT, KDR) were highly conserved in PDCL and amenable for individualized therapeutic approaches. Integrative genomic and transcriptomic approaches further demonstrated that PDCL more closely resemble molecular and prognostic features of PLC than established cell lines and are valuable tool for direct target evaluation. Our integrative analysis demonstrates that PDCL represents refined model for discovery of relevant molecular subgroups and exploration of precision medicine approaches for the treatment of this deadly disease.


Assuntos
Linhagem Celular Tumoral/patologia , Neoplasias Hepáticas/patologia , Medicina de Precisão/métodos , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/antagonistas & inibidores , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinogênese/genética , Análise Mutacional de DNA , Perfilação da Expressão Gênica/métodos , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Camundongos , Mutação , Cultura Primária de Células/métodos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
17.
Nat Commun ; 9(1): 327, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29382830

RESUMO

Disease epidemiology during ageing shows a transition from cancer to degenerative chronic disorders as dominant contributors to mortality in the old. Nevertheless, it has remained unclear to what extent molecular signatures of ageing reflect this phenomenon. Here we report on the identification of a conserved transcriptomic signature of ageing based on gene expression data from four vertebrate species across four tissues. We find that ageing-associated transcriptomic changes follow trajectories similar to the transcriptional alterations observed in degenerative ageing diseases but are in opposite direction to the transcriptomic alterations observed in cancer. We confirm the existence of a similar antagonism on the genomic level, where a majority of shared risk alleles which increase the risk of cancer decrease the risk of chronic degenerative disorders and vice versa. These results reveal a fundamental trade-off between cancer and degenerative ageing diseases that sheds light on the pronounced shift in their epidemiology during ageing.


Assuntos
Envelhecimento/genética , Doenças Cardiovasculares/genética , Diabetes Mellitus/genética , Neoplasias/genética , Doenças Neurodegenerativas/genética , Transcriptoma , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/patologia , Criança , Pré-Escolar , Doença Crônica , Diabetes Mellitus/sangue , Diabetes Mellitus/patologia , Fundulidae/genética , Fundulidae/crescimento & desenvolvimento , Fundulidae/metabolismo , Ontologia Genética , Genoma Humano , Humanos , Lactente , Fígado/crescimento & desenvolvimento , Fígado/metabolismo , Camundongos , Pessoa de Meia-Idade , Anotação de Sequência Molecular , Neoplasias/metabolismo , Neoplasias/patologia , Doenças Neurodegenerativas/sangue , Doenças Neurodegenerativas/patologia , Pele/crescimento & desenvolvimento , Pele/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo
18.
Endocr Connect ; 7(1): 47-55, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29133385

RESUMO

Poorly differentiated thyroid carcinoma (PDTC) is a rare malignancy with higher mortality than well-differentiated thyroid carcinoma. The histological diagnosis can be difficult as well as the therapy. Improved diagnosis and new targeted therapies require knowledge of DNA sequence changes in cancer-relevant genes. The TruSeq Amplicon Cancer Panel was used to screen cancer genomes from 25 PDTC patients for somatic single-nucleotide variants in 48 genes known to represent mutational hotspots. A total of 4490 variants were found in 23 tissue samples of PDTC. Ninety-eight percent (4392) of these variants did not meet the inclusion criteria, while 98 potentially pathogenic or pathogenic variants remained after filtering. These variants were distributed over 33 genes and were all present in a heterozygous state. Five tissue samples harboured not a single variant. Predominantly, variants in P53 (43% of tissue samples) were identified, while less frequently, variants in APC, ERBB4, FLT3, KIT, SMAD4 and BRAF (each in 17% of tissue samples) as well as ATM, EGFR and FBXW7 (each in 13% of tissue samples) were observed. This study identified new potential genetic targets for further research in PDTC. Of particular interest are four observed ERBB4 (alias HER4) variants, which have not been connected to this type of thyroid carcinoma so far. In addition, APC and SMAD4 mutations have not been reported in this subtype of cancer either. In contrast to other reports, we did not find CTNNB1 variants.

19.
Sci Rep ; 7(1): 13161, 2017 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-29030573

RESUMO

Highly active, structurally disordered CoFe2O4/CoO electrocatalysts are synthesized by pulsed laser fragmentation in liquid (PLFL) of a commercial CoFe2O4 powder dispersed in water. A partial transformation of the CoFe2O4 educt to CoO is observed and proposed to be a thermal decomposition process induced by the picosecond pulsed laser irradiation. The overpotential in the OER in aqueous alkaline media at 10 mA cm-2 is reduced by 23% compared to the educt down to 0.32 V with a Tafel slope of 71 mV dec-1. Importantly, the catalytic activity is systematically adjustable by the number of PLFL treatment cycles. The occurrence of thermal melting and decomposition during one PLFL cycle is verified by modelling the laser beam energy distribution within the irradiated colloid volume and comparing the by single particles absorbed part to threshold energies. Thermal decomposition leads to a massive reduction in particle size and crystal transformations towards crystalline CoO and amorphous CoFe2O4. Subsequently, thermal melting forms multi-phase spherical and network-like particles. Additionally, Fe-based layered double hydroxides at higher process cycle repetitions emerge as a byproduct. The results show that PLFL is a promising method that allows modification of the structural order in oxides and thus access to catalytically interesting materials.

20.
Dalton Trans ; 46(18): 6039-6048, 2017 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-28426069

RESUMO

Indium tin oxide (ITO) particle coatings are known for high transparency in the visible, good conductive properties and near-infrared absorption. These properties depend on ITO particle's stoichiometric composition, defects and size. Here we present a method to gradually change ITO particle's optical properties by a simple and controlled laser irradiation process. The defined irradiation process and controlled energy dose input allows one to engineer the absorption and transmission of coatings made from these particles. We investigate the role of the surrounding solvent, influence of laser fluence and the specific energy dose targeting modification of the ITO particle's morphology and chemistry by stepwise laser irradiation in a free liquid jet. TEM, SEM, EDX, XPS, XRD and Raman are used to elucidate the structural, morphological and chemical changes of the laser-induced ITO particles. On the basis of these results the observed modification of the optical properties is tentatively attributed to chemical changes, e.g. laser-induced defects or partial reduction.

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