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1.
Cell ; 172(4): 857-868.e15, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29336889

RESUMO

The mechanism by which the wild-type KRAS allele imparts a growth inhibitory effect to oncogenic KRAS in various cancers, including lung adenocarcinoma (LUAD), is poorly understood. Here, using a genetically inducible model of KRAS loss of heterozygosity (LOH), we show that KRAS dimerization mediates wild-type KRAS-dependent fitness of human and murine KRAS mutant LUAD tumor cells and underlies resistance to MEK inhibition. These effects are abrogated when wild-type KRAS is replaced by KRASD154Q, a mutant that disrupts dimerization at the α4-α5 KRAS dimer interface without changing other fundamental biochemical properties of KRAS, both in vitro and in vivo. Moreover, dimerization has a critical role in the oncogenic activity of mutant KRAS. Our studies provide mechanistic and biological insights into the role of KRAS dimerization and highlight a role for disruption of dimerization as a therapeutic strategy for KRAS mutant cancers.


Assuntos
Adenocarcinoma de Pulmão , Inibidores Enzimáticos/farmacologia , Neoplasias Pulmonares , MAP Quinase Quinase Quinases/antagonistas & inibidores , Mutação de Sentido Incorreto , Multimerização Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/enzimologia , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Substituição de Aminoácidos , Animais , Linhagem Celular Tumoral , Células HEK293 , Humanos , Perda de Heterozigosidade , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Camundongos , Camundongos Knockout , Multimerização Proteica/genética , Proteínas Proto-Oncogênicas p21(ras)/genética
2.
Cell ; 168(1-2): 59-72.e13, 2017 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-28065413

RESUMO

Chromosomal translocations of the mixed-lineage leukemia (MLL) gene with various partner genes result in aggressive leukemia with dismal outcomes. Despite similar expression at the mRNA level from the wild-type and chimeric MLL alleles, the chimeric protein is more stable. We report that UBE2O functions in regulating the stability of wild-type MLL in response to interleukin-1 signaling. Targeting wild-type MLL degradation impedes MLL leukemia cell proliferation, and it downregulates a specific group of target genes of the MLL chimeras and their oncogenic cofactor, the super elongation complex. Pharmacologically inhibiting this pathway substantially delays progression, and it improves survival of murine leukemia through stabilizing wild-type MLL protein, which displaces the MLL chimera from some of its target genes and, therefore, relieves the cellular oncogenic addiction to MLL chimeras. Stabilization of MLL provides us with a paradigm in the development of therapies for aggressive MLL leukemia and perhaps for other cancers caused by translocations.


Assuntos
Leucemia Aguda Bifenotípica/tratamento farmacológico , Leucemia Aguda Bifenotípica/metabolismo , Proteólise/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Interleucina-1/metabolismo , Quinases Associadas a Receptores de Interleucina-1/antagonistas & inibidores , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteína de Leucina Linfoide-Mieloide/metabolismo , Enzimas de Conjugação de Ubiquitina
3.
Mol Cell ; 77(3): 633-644.e5, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-31836388

RESUMO

Metastatic melanoma is an aggressive disease, despite recent improvements in therapy. Eradicating all melanoma cells even in drug-sensitive tumors is unsuccessful in patients because a subset of cells can transition to a slow-cycling state, rendering them resistant to most targeted therapy. It is still unclear what pathways define these subpopulations and promote this resistant phenotype. In the current study, we show that Wnt5A, a non-canonical Wnt ligand that drives a metastatic, therapy-resistant phenotype, stabilizes the half-life of p53 and uses p53 to initiate a slow-cycling state following stress (DNA damage, targeted therapy, and aging). Inhibiting p53 blocks the slow-cycling phenotype and sensitizes melanoma cells to BRAF/MEK inhibition. In vivo, this can be accomplished with a single dose of p53 inhibitor at the commencement of BRAF/MEK inhibitor therapy. These data suggest that taking the paradoxical approach of inhibiting rather than activating wild-type p53 may sensitize previously resistant metastatic melanoma cells to therapy.


Assuntos
Melanoma/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Wnt-5a/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , MAP Quinase Quinase Quinases/metabolismo , Melanoma/genética , Melanoma/patologia , Terapia de Alvo Molecular , Mutação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Proteína Supressora de Tumor p53/fisiologia
4.
Proc Natl Acad Sci U S A ; 121(13): e2314261121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38513094

RESUMO

By releasing specialized metabolites, plants modify their environment. Whether and how specialized metabolites protect plants against toxic levels of trace elements is not well understood. We evaluated whether benzoxazinoids, which are released into the soil by major cereals, can confer protection against arsenic toxicity. Benzoxazinoid-producing maize plants performed better in arsenic-contaminated soils than benzoxazinoid-deficient mutants in the greenhouse and the field. Adding benzoxazinoids to the soil restored the protective effect, and the effect persisted to the next crop generation via positive plant-soil feedback. Arsenate levels in the soil and total arsenic levels in the roots were lower in the presence of benzoxazinoids. Thus, the protective effect of benzoxazinoids is likely soil-mediated and includes changes in soil arsenic speciation and root accumulation. We conclude that exuded specialized metabolites can enhance protection against toxic trace elements via soil-mediated processes and may thereby stabilize crop productivity in polluted agroecosystems.


Assuntos
Arsênio , Poluentes do Solo , Oligoelementos , Arsênio/metabolismo , Oligoelementos/metabolismo , Zea mays/genética , Zea mays/metabolismo , Benzoxazinas/metabolismo , Plantas/metabolismo , Solo , Poluentes do Solo/análise , Raízes de Plantas/metabolismo
5.
EMBO J ; 40(7): e106177, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33694180

RESUMO

TDP-43 is the major component of pathological inclusions in most ALS patients and in up to 50% of patients with frontotemporal dementia (FTD). Heterozygous missense mutations in TARDBP, the gene encoding TDP-43, are one of the common causes of familial ALS. In this study, we investigate TDP-43 protein behavior in induced pluripotent stem cell (iPSC)-derived motor neurons from three ALS patients with different TARDBP mutations, three healthy controls and an isogenic control. TARDPB mutations induce several TDP-43 changes in spinal motor neurons, including cytoplasmic mislocalization and accumulation of insoluble TDP-43, C-terminal fragments, and phospho-TDP-43. By generating iPSC lines with allele-specific tagging of TDP-43, we find that mutant TDP-43 initiates the observed disease phenotypes and has an altered interactome as indicated by mass spectrometry. Our findings also indicate that TDP-43 proteinopathy results in a defect in mitochondrial transport. Lastly, we show that pharmacological inhibition of histone deacetylase 6 (HDAC6) restores the observed TDP-43 pathologies and the axonal mitochondrial motility, suggesting that HDAC6 inhibition may be an interesting therapeutic target for neurodegenerative disorders linked to TDP-43 pathology.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Transporte Axonal , Proteínas de Ligação a DNA/genética , Desacetilase 6 de Histona/metabolismo , Neurônios Motores/metabolismo , Esclerose Lateral Amiotrófica/genética , Células Cultivadas , Proteínas de Ligação a DNA/metabolismo , Desacetilase 6 de Histona/antagonistas & inibidores , Inibidores de Histona Desacetilases/farmacologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Mitocôndrias/metabolismo , Neurônios Motores/citologia , Neurônios Motores/efeitos dos fármacos , Mutação de Sentido Incorreto
6.
EMBO Rep ; 24(4): e56325, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36794620

RESUMO

The frequency of p53 mutations in colorectal cancer (CRC) is approximately 40-50%. A variety of therapies are being developed to target tumors expressing mutant p53. However, potential therapeutic targets for CRC expressing wild-type p53 are rare. In this study, we show that METTL14 is transcriptionally activated by wild-type p53 and suppresses tumor growth only in p53-wild-type (p53-WT) CRC cells. METTL14 deletion promotes both AOM/DSS and AOM-induced CRC growth in mouse models with the intestinal epithelial cell-specific knockout of METTL14. Additionally, METTL14 restrains aerobic glycolysis in p53-WT CRC, by repressing SLC2A3 and PGAM1 expression via selectively promoting m6 A-YTHDF2-dependent pri-miR-6769b/pri-miR-499a processing. Biosynthetic mature miR-6769b-3p and miR-499a-3p decrease SLC2A3 and PGAM1 levels, respectively, and suppress malignant phenotypes. Clinically, METTL14 only acts as a beneficial prognosis factor for the overall survival of p53-WT CRC patients. These results uncover a new mechanism for METTL14 inactivation in tumors and, most importantly, reveal that the activation of METTL14 is a critical mechanism for p53-dependent cancer growth inhibition, which could be targeted for therapy in p53-WT CRC.


Assuntos
Neoplasias Colorretais , MicroRNAs , Animais , Camundongos , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Glicólise/genética , MicroRNAs/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
7.
Clin Microbiol Rev ; 36(4): e0010022, 2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-38038445

RESUMO

The characterization of wild-type minimum inhibitory concentration (MIC) and zone diameter distributions with the setting of epidemiological cut-off values (ECOFFs or ECVs) provides a reference for the otherwise relative MIC values in the international system for antimicrobial susceptibility testing. Distributions of MIC values for a species and an agent follow a log-normal distribution, which in the absence of resistance mechanisms is monomodal and designated wild type (WT). The upper end of the WT distribution, the ECOFF, can be identified with statistical methods. In the presence of phenotypically detectable resistance, the distribution has at least one more mode (the non-WT), but despite this, the WT is most often identifiable using the same methods. The ECOFF provides the most sensitive measure of resistance development in a species against an agent. The WT and non-WT modes are independent of the organism´s response to treatment, but when the European Committee on Antimicrobial Susceptibility Testing (EUCAST) determines the clinical breakpoints, the committee avoids breakpoints that split WT distributions of target species. This is to avoid the poorer reproducibility of susceptibility categorization when breakpoints split major populations but also because the EUCAST has failed to identify different clinical outcomes for isolates with different MIC values inside the wild-type distribution. In laboratory practice, the ECOFF is used to screen for and exclude resistance and allows the comparison of resistance between systems with different breakpoints from different breakpoint organizations, breakpoints evolving over time, and different breakpoints between human and animal medicine. The EUCAST actively encourages colleagues to question MIC distributions as presented on the website (https://www.eucast.org/mic_and_zone_distributions_and_ecoffs) and to contribute MIC and inhibition zone diameter data.


Assuntos
Anti-Infecciosos , Animais , Humanos , Reprodutibilidade dos Testes , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia
8.
Curr Issues Mol Biol ; 46(8): 8197-8208, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39194701

RESUMO

Multiple myeloma (MM) first-line treatment algorithms include immuno-chemotherapy (ICT) induction, high-dose chemotherapy (HDCT) and autologous stem cell transplant (ASCT) consolidation, followed by lenalidomide maintenance. After these initial therapies, most patients suffer a disease relapse and require subsequent treatment lines including ICT, additional HDCT and ASCT, or novel immunotherapies. The presence of somatic mutations in peripheral blood cells has been associated with adverse outcomes in a variety of hematological malignancies. Nonsense and frameshift mutations in the PPM1D gene, a frequent driver alteration in clonal hematopoiesis (CH), lead to the gain-of-function of Wip1 phosphatase, which may impair the p53-dependent G1 checkpoint and promote cell proliferation. Here, we determined the presence of PPM1D gene mutations in peripheral blood cells of 75 subsequent myeloma patients in remission after first or second HDCT/ASCT. The prevalence of truncating PPM1D gene mutations emerged at 1.3% after first HDCT/ASCT, and 7.3% after second HDCT/ASCT, with variant allele frequencies (VAF) of 0.01 to 0.05. Clinical outcomes were inferior in the PPM1D-mutated (PPM1Dmut) subset with median progression-free survival (PFS) of 15 vs. 37 months (p = 0.0002) and median overall survival (OS) of 36 vs. 156 months (p = 0.001) for the PPM1Dmut and PPM1Dwt population, respectively. Our data suggest that the occurrence of PPM1D gene mutations in peripheral blood cells correlates with inferior outcomes after ASCT in patients with multiple myeloma.

9.
Oncologist ; 29(3): e337-e344, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38071748

RESUMO

BACKGROUND: Liquid biopsy (LB) is a non-invasive tool to evaluate the heterogeneity of tumors. Since RAS mutations (RAS-mut) play a major role in resistance to antiepidermal growth factor receptor inhibitors (EGFR) monoclonal antibodies (Mabs), serial monitoring of RAS-mut with LB may be useful to guide treatment. The main aim of this study was to evaluate the prognostic value of the loss of RAS-mut (NeoRAS-wt) in LB, during the treatment of metastatic colorectal cancer (mCRC). METHODS: A retrospective study was conducted on patients with mCRC between January 2018 and December 2021. RAS-mut were examined in tissue biopsy, at mCRC diagnosis, and with LB, during treatment. RESULTS: Thirty-nine patients with RAS-mut mCRC were studied. LB was performed after a median of 3 lines (0-7) of systemic treatment including anti-vascular endothelial growth factor (anti-VEGF) Mabs. NeoRAS-wt was detected in 13 patients (33.3%); 9 (69.2%) of them received further treatment with anti-EGFR Mabs with a disease control rate of 44.4%. Median overall survival (OS), from the date of LB testing, was 20 months in the NeoRAS-wt group and 9 months in the persistent RAS-mut group (log-rank 2.985; P = .08), with a 12-month OS of 84.6% and 57.7%, respectively. NeoRAS-wt was identified as a predictor of survival (HR = 0.29; P = .007), with an 11-month improvement in median OS and a 71% decrease in risk of death, in heavily pretreated patients. CONCLUSIONS: In conclusion, monitoring clonal evolution in mCRC by LB may provide an additional treatment line for patients with NeoRAS-wt in advanced disease.


Assuntos
Antineoplásicos , Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Humanos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Estudos Retrospectivos , Antineoplásicos/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Biópsia Líquida , Mutação
10.
Microbiology (Reading) ; 170(8)2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39212644

RESUMO

In this opinion piece, we consider the meaning of the term 'wild type' in the context of microbiology. This is especially pertinent in the post-genomic era, where we have a greater awareness of species diversity than ever before. Genomic heterogeneity, in vitro evolution/selection pressures, definition of 'the wild', the size and importance of the pan-genome, gene-gene interactions (epistasis), and the nature of the 'wild-type gene' are all discussed. We conclude that wild type is an outdated and even misleading phrase that should be gradually phased out.


Assuntos
Genoma Bacteriano , Bactérias/genética , Bactérias/classificação , Bactérias/isolamento & purificação , Evolução Molecular , Variação Genética , Genômica
11.
Expert Rev Mol Med ; 26: e5, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563164

RESUMO

Glioblastoma IDH wild type (GBM) is a very aggressive brain tumour, characterised by an infiltrative growth pattern and by a prominent neoangiogenesis. Its prognosis is unfortunately dismal, and the median overall survival of GBM patients is short (15 months). Clinical management is based on bulk tumour removal and standard chemoradiation with the alkylating drug temozolomide, but the tumour invariably recurs leading to patient's death. Clinical options for GBM patients remained unaltered for almost two decades until the encouraging results obtained by the phase II REGOMA trial allowed the introduction of the multikinase inhibitor regorafenib as a preferred regimen in relapsed GBM treatment by the National Comprehensive Cancer Network (NCCN) 2020 Guideline. Regorafenib, a sorafenib derivative, targets kinases associated with angiogenesis (VEGFR 1-3), as well as oncogenesis (c-KIT, RET, FGFR) and stromal kinases (FGFR, PDGFR-b). It was already approved for metastatic colorectal cancers and hepatocellular carcinomas. The aim of the present review is to focus on both the molecular and clinical knowledge collected in these first three years of regorafenib use in GBM.


Assuntos
Antineoplásicos , Glioblastoma , Neoplasias Hepáticas , Compostos de Fenilureia , Piridinas , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Resultado do Tratamento , Neoplasias Hepáticas/tratamento farmacológico
12.
J Clin Microbiol ; 62(4): e0152823, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38501836

RESUMO

Although the Vitek 2 system is broadly used for antifungal susceptibility testing of Candida spp., its performance against Candida auris has been assessed using limited number of isolates recovered from restricted geographic areas. We therefore compared Vitek 2 system with the reference Clinical and Laboratory Standards Institute (CLSI) broth microdilution method using an international collection of 100 C. auris isolates belonging to different clades. The agreement ±1 twofold dilution between the two methods and the categorical agreement (CA) based on the Centers for Disease Control and Prevention's (CDC's) tentative resistance breakpoints and Vitek 2-specific wild-type upper limit values (WT-ULVs) were determined. The CLSI-Vitek 2 agreement was poor for 5-flucytosine (0%), fluconazole (16%), and amphotericin B (29%), and moderate for voriconazole (61%), micafungin (67%), and caspofungin (81%). Significant interpretation errors were recorded using the CDC breakpoints for amphotericin B (31% CA, 69% major errors; MaEs) and fluconazole (69% CA, 31% very major errors; VmEs), but not for echinocandins (99% CA, 1% MaEs for both micafungin and caspofungin) for which the Vitek 2 allowed correct categorization of echinocandin-resistant FKS1 mutant isolates. Discrepancies were reduced when the Vitek 2 WT-ULV of 16 mg/L for amphotericin B (98% CA, 2% MaEs) and of 4 mg/L for fluconazole (96% CA, 1% MaEs, 3% VmEs) were used. In conclusion, the Vitek 2 system performed well for echinocandin susceptibility testing of C .auris. Resistance to fluconazole was underestimated whereas resistance to amphotericin B was overestimated using the CDC breakpoints of ≥32 and ≥2 mg/L, respectively. Vitek 2 minimun inhibitory concentrations (MICs) >4 mg/L indicated resistance to fluconazole and Vitek 2 MICs ≤16 mg/L indicated non-resistance to amphotericin B.


Assuntos
Anfotericina B , Fluconazol , Humanos , Fluconazol/farmacologia , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Candida auris , Micafungina , Caspofungina , Testes de Sensibilidade Microbiana , Equinocandinas/farmacologia
13.
J Transl Med ; 22(1): 578, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890658

RESUMO

BACKGROUND: IDH1-wildtype glioblastoma multiforme (IDHwt-GBM) is a highly heterogeneous and aggressive brain tumour characterised by a dismal prognosis and significant challenges in accurately predicting patient outcomes. To address these issues and personalise treatment approaches, we aimed to develop and validate robust multiomics molecular subtypes of IDHwt-GBM. Through this, we sought to uncover the distinct molecular signatures underlying these subtypes, paving the way for improved diagnosis and targeted therapy for this challenging disease. METHODS: To identify stable molecular subtypes among 184 IDHwt-GBM patients from TCGA, we used the consensus clustering method to consolidate the results from ten advanced multiomics clustering approaches based on mRNA, lncRNA, and mutation data. We developed subtype prediction models using the PAM and machine learning algorithms based on mRNA and MRI data for enhanced clinical utility. These models were validated in five independent datasets, and an online interactive system was created. We conducted a comprehensive assessment of the clinical impact, drug treatment response, and molecular associations of the IDHwt-GBM subtypes. RESULTS: In the TCGA cohort, two molecular subtypes, class 1 and class 2, were identified through multiomics clustering of IDHwt-GBM patients. There was a significant difference in survival between Class 1 and Class 2 patients, with a hazard ratio (HR) of 1.68 [1.15-2.47]. This difference was validated in other datasets (CGGA: HR = 1.75[1.04, 2.94]; CPTAC: HR = 1.79[1.09-2.91]; GALSS: HR = 1.66[1.09-2.54]; UCSF: HR = 1.33[1.00-1.77]; UPENN HR = 1.29[1.04-1.58]). Additionally, class 2 was more sensitive to treatment with radiotherapy combined with temozolomide, and this sensitivity was validated in the GLASS cohort. Correspondingly, class 2 and class 1 exhibited significant differences in mutation patterns, enriched pathways, programmed cell death (PCD), and the tumour immune microenvironment. Class 2 had more mutation signatures associated with defective DNA mismatch repair (P = 0.0021). Enriched pathways of differentially expressed genes in class 1 and class 2 (P-adjust < 0.05) were mainly related to ferroptosis, the PD-1 checkpoint pathway, the JAK-STAT signalling pathway, and other programmed cell death and immune-related pathways. The different cell death modes and immune microenvironments were validated across multiple datasets. Finally, our developed survival prediction model, which integrates molecular subtypes, age, and sex, demonstrated clinical benefits based on the decision curve in the test set. We deployed the molecular subtyping prediction model and survival prediction model online, allowing interactive use and facilitating user convenience. CONCLUSIONS: Molecular subtypes were identified and verified through multiomics clustering in IDHwt-GBM patients. These subtypes are linked to specific mutation patterns, the immune microenvironment, prognoses, and treatment responses.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Isocitrato Desidrogenase , Imageamento por Ressonância Magnética , RNA Mensageiro , Humanos , Análise por Conglomerados , Glioblastoma/genética , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Glioblastoma/terapia , Prognóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Isocitrato Desidrogenase/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Mutação/genética , Reprodutibilidade dos Testes , Estudos de Coortes , Resultado do Tratamento , Multiômica
14.
Appl Environ Microbiol ; 90(5): e0233023, 2024 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-38587374

RESUMO

Improving our understanding of the transcriptional changes of Saccharomyces cerevisiae during fermentation of lignocellulosic hydrolysates is crucial for the creation of more efficient strains to be used in biorefineries. We performed RNA sequencing of a CEN.PK laboratory strain, two industrial strains (KE6-12 and Ethanol Red), and two wild-type isolates of the LBCM collection when cultivated anaerobically in wheat straw hydrolysate. Many of the differently expressed genes identified among the strains have previously been reported to be important for tolerance to lignocellulosic hydrolysates or inhibitors therein. Our study demonstrates that stress responses typically identified during aerobic conditions such as glutathione metabolism, osmotolerance, and detoxification processes also are important for anaerobic processes. Overall, the transcriptomic responses were largely strain dependent, and we focused our study on similarities and differences in the transcriptomes of the LBCM strains. The expression of sugar transporter-encoding genes was higher in LBCM31 compared with LBCM109 that showed high expression of genes involved in iron metabolism and genes promoting the accumulation of sphingolipids, phospholipids, and ergosterol. These results highlight different evolutionary adaptations enabling S. cerevisiae to strive in lignocellulosic hydrolysates and suggest novel gene targets for improving fermentation performance and robustness. IMPORTANCE: The need for sustainable alternatives to oil-based production of biochemicals and biofuels is undisputable. Saccharomyces cerevisiae is the most commonly used industrial fermentation workhorse. The fermentation of lignocellulosic hydrolysates, second-generation biomass unsuited for food and feed, is still hampered by lowered productivities as the raw material is inhibitory for the cells. In order to map the genetic responses of different S. cerevisiae strains, we performed RNA sequencing of a CEN.PK laboratory strain, two industrial strains (KE6-12 and Ethanol Red), and two wild-type isolates of the LBCM collection when cultivated anaerobically in wheat straw hydrolysate. While the response to inhibitors of S. cerevisiae has been studied earlier, this has in previous studies been done in aerobic conditions. The transcriptomic analysis highlights different evolutionary adaptations among the different S. cerevisiae strains and suggests novel gene targets for improving fermentation performance and robustness.


Assuntos
Fermentação , Lignina , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Lignina/metabolismo , Estresse Fisiológico , Transcriptoma , Triticum/microbiologia , Triticum/metabolismo , Regulação Fúngica da Expressão Gênica
15.
J Med Virol ; 96(2): e29400, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38293843

RESUMO

Serum hepatitis B virus (HBV) spliced RNAs (spRNAs) are ubiquitous in HBV-infected patients; however, their clinical significance remains unknown. Therefore, we aimed to explore the relationship between HBV spRNAs and liver disease progression in chronic hepatitis B (CHB) patients; in vitro cell line assessment was also performed. The serum HBV wild-type RNA (wtRNA) and spRNA levels were individually quantified in a cohort of 279 treatment-naïve, hepatitis B e antigen positive CHB patients with or without cirrhosis. The spRNA proportion was determined as (spRNA × 100%)/(spRNAs + wtRNA). 20 patients' serum samples underwent spRNA species profiling using next-generation sequencing. Serum spRNA species 1, 2, 3, 4, and 5 were the most common variants. The spRNA proportion varied from 0.00% to 19.02%, with higher levels in HBV genotype C patients than in those with genotype B (1.76% vs. 0.84%, p < 0.001). The spRNA proportion was positively associated with the alanine aminotransferase levels (r = 0.144, p = 0.053) and significantly higher in cirrhotic than in non-cirrhotic patients (1.69% vs. 1.04%, p = 0.001). Multivariate analysis revealed a 2.566-fold higher risk of cirrhosis in patients with elevated spRNA proportion (p = 0.024). In vitro experiments confirmed that spRNAs contributed to hepatic stellate cell activation, which is critical in liver fibrosis development. Therefore, increased HBV spRNA expression poses a risk for liver disease progression. Quantifying serum HBV spRNAs can aid in monitoring liver disease progression. Furthermore, the therapeutic targeting of spRNAs may improve the prognosis of patients with CHB.


Assuntos
Vírus da Hepatite B , Hepatite B Crônica , Humanos , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , RNA/uso terapêutico , Cirrose Hepática/complicações , Antígenos E da Hepatite B , Progressão da Doença , DNA Viral/genética
16.
Respir Res ; 25(1): 215, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38764025

RESUMO

BACKGROUND: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of lung cancer patients with mutated EGFR. However, the efficacy of EGFR-TKIs in wild-type EGFR tumors has been shown to be marginal. Methods that can sensitize EGFR-TKIs to EGFR wild-type NSCLC remain rare. Hence, we determined whether combination treatment can maximize the therapeutic efficacy of EGFR-TKIs. METHODS: We established a focused drug screening system to investigate candidates for overcoming the intrinsic resistance of wild-type EGFR NSCLC to EGFR-TKIs. Molecular docking assays and western blotting were used to identify the binding mode and blocking effect of the candidate compounds. Proliferation assays, analyses of drug interactions, colony formation assays, flow cytometry and nude mice xenograft models were used to determine the effects and investigate the molecular mechanism of the combination treatment. RESULTS: Betulinic acid (BA) is effective at targeting EGFR and synergizes with EGFR-TKIs (gefitinib and osimertinib) preferentially against wild-type EGFR. BA showed inhibitory activity due to its interaction with the ATP-binding pocket of EGFR and dramatically enhanced the suppressive effects of EGFR-TKIs by blocking EGFR and modulating the EGFR-ATK-mTOR axis. Mechanistic studies revealed that the combination strategy activated EGFR-induced autophagic cell death and that the EGFR-AKT-mTOR signaling pathway was essential for completing autophagy and cell cycle arrest. Activation of the mTOR pathway or blockade of autophagy by specific chemical agents markedly attenuated the effect of cell cycle arrest. In vivo administration of the combination treatment caused marked tumor regression in the A549 xenografts. CONCLUSIONS: BA is a potential wild-type EGFR inhibitor that plays a critical role in sensitizing EGFR-TKI activity. BA combined with an EGFR-TKI effectively suppressed the proliferation and survival of intrinsically resistant lung cancer cells via the inhibition of EGFR as well as the induction of autophagy-related cell death, indicating that BA combined with an EGFR-TKI may be a potential therapeutic strategy for overcoming the primary resistance of wild-type EGFR-positive lung cancers.


Assuntos
Autofagia , Ácido Betulínico , Carcinoma Pulmonar de Células não Pequenas , Sinergismo Farmacológico , Receptores ErbB , Neoplasias Pulmonares , Triterpenos Pentacíclicos , Inibidores de Proteínas Quinases , Animais , Humanos , Camundongos , Células A549 , Acrilamidas/farmacologia , Compostos de Anilina/farmacologia , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Autofagia/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Receptores ErbB/antagonistas & inibidores , Gefitinibe/farmacologia , Indóis , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas , Transdução de Sinais/efeitos dos fármacos , Triterpenos/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
17.
Virol J ; 21(1): 264, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39449007

RESUMO

OBJECTIVE: To analyze the genotypes of VZV in Jiangsu province to identify vaccine strains and wild strains, providing a molecular biological background for the effective prevention and control of varicella. METHOD: Stratified sampling was used to collect herpes fluid or throat swab from patients diagnosed with varicella. ORF22 was carried out, and the restriction enzyme site of ORF38, ORF54 and ORF62 were detected. RESULTS: All 207 virus strains were Clade 2 type by sequencing the PCR products of ORF22. The sequencing results showed that five SNP sites changed compared to the Dumas reference strain(Clade 1). From A to G at 37,902, from T to c at 38,055, from A to C at 38,081, and from G to A at 38,177, from G to A at 39,394. The prevalent VZV genotypes in Jiangsu is consistent with the P-Oka. The restriction enzyme site analysis of PCR amplification products from ORF38 (PstI), ORF54 (BglI), ORF62 (SmaI) showed that all 207 virus strains were wild-type. There were two different types of the wild strains, and 183 strains (88.4%) were PstI (+), BglI (+), SmaI (-). The wild strains between different regions showed no significant differences (χ2 = 0.05, P = 0.982). CONCLUSIONS: The prevalent VZV genotypes are Clade 2 and the prevalent virus strains are wild strains in Jiangsu Province, the primary wild strain observed is mainly PstI (+), BglI (+), SmaI (-).


Assuntos
Genótipo , Herpesvirus Humano 3 , Humanos , China/epidemiologia , Herpesvirus Humano 3/genética , Herpesvirus Humano 3/isolamento & purificação , Herpesvirus Humano 3/classificação , Criança , Adulto , Adolescente , Feminino , Pré-Escolar , Adulto Jovem , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA , Lactente , DNA Viral/genética , Varicela/virologia , Varicela/epidemiologia , Idoso , Filogenia , Reação em Cadeia da Polimerase
18.
J Neurooncol ; 169(1): 61-72, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38762828

RESUMO

PURPOSE: Frailty increases the risk of mortality among patients. We studied the prognostic significance of frailty using the modified 5-item frailty index (5-mFI) in patients harboring a newly diagnosed supratentorial glioblastoma, IDH-wildtype. METHODS: We retrospectively reviewed records of patients surgical treated at a single neurosurgical institution at the standard radiochemotherapy era (January 2006 - December 2021). Inclusion criteria were: age ≥ 18, newly diagnosed glioblastoma, IDH-wildtype, supratentorial location, available data to assess the 5-mFI index. RESULTS: A total of 694 adult patients were included. The median overall survival was longer in the non-frail subgroup (5-mFI < 2, n = 538 patients; 14.3 months, 95%CI 12.5-16.0) than in the frail subgroup (5-mFI ≥ 2, n = 156 patients; 4.7 months, 95%CI 4.0-6.5 months; p < 0.001). 5-mFI ≥ 2 (adjusted Hazard Ratio (aHR) 1.31; 95%CI 1.07-1.61; p = 0.009) was an independent predictor of a shorter overall survival while age ≤ 60 years (aHR 0.78; 95%CI 0.66-0.93; p = 0.007), KPS score ≥ 70 (aHR 0.71; 95%CI 0.58-0.87; p = 0.001), unilateral location (aHR 0.67; 95%CI 0.52-0.87; p = 0.002), total removal (aHR 0.54; 95%CI 0.44-0.64; p < 0.0001), and standard radiochemotherapy protocol (aHR 0.32; 95%CI 0.26-0.38; p < 0.0001) were independent predictors of a longer overall survival. Frailty remained an independent predictor of overall survival within the subgroup of patients undergoing a first-line oncological treatment after surgery (n = 549) and within the subgroup of patients who benefited from a total removal plus adjuvant standard radiochemotherapy (n = 209). CONCLUSION: In newly diagnosed supratentorial glioblastoma, IDH-wildtype patients treated at the standard combined radiochemotherapy era, frailty, defined using a 5-mFI score ≥ 2 was an independent predictor of overall survival.


Assuntos
Fragilidade , Glioblastoma , Isocitrato Desidrogenase , Humanos , Glioblastoma/mortalidade , Glioblastoma/terapia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fragilidade/mortalidade , Isocitrato Desidrogenase/genética , Idoso , Adulto , Prognóstico , Taxa de Sobrevida , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Seguimentos , Neoplasias Supratentoriais/mortalidade , Neoplasias Supratentoriais/terapia
19.
J Neurooncol ; 167(1): 89-97, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38376766

RESUMO

PURPOSE: Glioblastomas (GBM) with subventricular zone (SVZ) contact have previously been associated with a specific epigenetic fingerprint. We aim to validate a reported bulk methylation signature to determine SVZ contact. METHODS: Methylation array analysis was performed on IDHwt GBM patients treated at our institution. The v11b4 classifier was used to ensure the inclusion of only receptor tyrosine kinase (RTK) I, II, and mesenchymal (MES) subtypes. Methylation-based assignment (SVZM ±) was performed using hierarchical cluster analysis. Magnetic resonance imaging (MRI) (T1ce) was independently reviewed for SVZ contact by three experienced readers. RESULTS: Sixty-five of 70 samples were classified as RTK I, II, and MES. Full T1ce MRI-based rater consensus was observed in 54 cases, which were retained for further analysis. Epigenetic SVZM classification and SVZ were strongly associated (OR: 15.0, p = 0.003). Thirteen of fourteen differential CpGs were located in the previously described differentially methylated LRBA/MAB21L2 locus. SVZ + tumors were linked to shorter OS (hazard ratio (HR): 3.80, p = 0.02) than SVZM + at earlier time points (time-dependency of SVZM, p < 0.05). Considering the SVZ consensus as the ground truth, SVZM classification yields a sensitivity of 96.6%, specificity of 36.0%, positive predictive value (PPV) of 63.6%, and negative predictive value (NPV) of 90.0%. CONCLUSION: Herein, we validated the specific epigenetic signature in GBM in the vicinity of the SVZ and highlighted the importance of methylation of a part of the LRBA/MAB21L2 gene locus. Whether SVZM can replace MRI-based SVZ assignment as a prognostic and diagnostic tool will require prospective studies of large, homogeneous cohorts.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Ventrículos Laterais/diagnóstico por imagem , Ventrículos Laterais/patologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Glioblastoma/diagnóstico por imagem , Glioblastoma/genética , Glioblastoma/patologia , Estudos Prospectivos , Metilação , Proteínas Adaptadoras de Transdução de Sinal , Proteínas do Olho , Peptídeos e Proteínas de Sinalização Intracelular
20.
J Neurooncol ; 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39377994

RESUMO

PURPOSE: To investigate the relationship between the tumor microenvironment (TME), tumor-related seizures (TRS), and cerebrospinal fluid (CSF) markers that predict preoperative seizures in patients with glioblastoma. METHODS: In total, 47 patients with isocitrate dehydrogenase (IDH) wild-type glioblastoma who underwent preoperative CSF examination, 3-T magnetic resonance spectroscopy (MRS), and neurological surgery between January 2017 and December 2023 were included. We measured the concentrations of soluble CD163 (sCD163), a soluble form of the M2 macrophage marker, in the CSF, the metabolite concentration on MRS, and the number of CD163-positive M2 macrophages in the tumor tissue. Factors associated with preoperative seizures were examined. RESULTS: Twelve patients (25.5%) had preoperative seizures. sCD163 levels in the CSF were positively correlated with the number of CD163-positive M2 macrophages in the tumor tissue, and both were significantly lower in the preoperative seizure group than in the non-preoperative seizure group (p = 0.0124 and p < 0.0001, respectively). MRS indicated that only glutathione (GSH) concentrations were higher in the preoperative seizure group than in the non-preoperative seizure group (2.55 mM and 1.87 mM, respectively; p = 0.0171). CD163-positive M2 macrophages were inversely correlated with GSH levels. sCD163 in the CSF had a high predictive accuracy (sensitivity, 91.7%; specificity, 54.3%; and area under the receiver operator curve, 0.745) for preoperative seizures. CONCLUSIONS: The CSF level of sCD163 is useful for predicting the TME and preoperative seizures in IDH wild-type glioblastoma.

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