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1.
EMBO Mol Med ; 16(5): 1115-1142, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38570712

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with an overall 5-year survival rate of <12% due to the lack of effective treatments. Novel treatment strategies are urgently needed. Here, PKMYT1 is identified through genome-wide CRISPR screens as a non-mutant, genetic vulnerability of PDAC. Higher PKMYT1 expression levels indicate poor prognosis in PDAC patients. PKMYT1 ablation inhibits tumor growth and proliferation in vitro and in vivo by regulating cell cycle progression and inducing apoptosis. Moreover, pharmacological inhibition of PKMYT1 shows efficacy in multiple PDAC cell models and effectively induces tumor regression without overt toxicity in PDAC cell line-derived xenograft and in more clinically relevant patient-derived xenograft models. Mechanistically, in addition to its canonical function of phosphorylating CDK1, PKMYT1 functions as an oncogene to promote PDAC tumorigenesis by regulating PLK1 expression and phosphorylation. Finally, TP53 function and PRKDC activation are shown to modulate the sensitivity to PKMYT1 inhibition. These results define PKMYT1 dependency in PDAC and identify potential therapeutic strategies for clinical translation.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Proteínas Serina-Treonina Quinases , Humanos , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/patologia , Animais , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Linhagem Celular Tumoral , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Camundongos , Proliferação de Células/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/antagonistas & inibidores , Apoptose/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas de Membrana , Proteínas Tirosina Quinases
2.
J Immunother Cancer ; 11(12)2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38056895

RESUMO

BACKGROUND: Cancer immunotherapies can induce durable tumor regression, but most patients do not respond. SETD2 mutation has been linked to the efficacy of immune checkpoint inhibitors (ICIs) immunotherapy. The functional importance of the SETD2 inactivation and how to modulate immunotherapy response remains unclear. METHODS: To explore the function of SETD2 in immunotherapy, knockout and subsequent functional experiments were conducted. Bulk RNA-seq, ATAC-seq, Chip-seq and single-cell RNA-seq were performed to dissect the mechanism and explore the immune microenvironment of mouse tumor. Flow cytometry was used to assess cell surface antigen and intratumoral T cell levels. RESULTS: We comprehensively determine the effect of SETD2 inactivation in ICIs therapy and elucidate the mechanistic impact on tumor immunity. Murine syngeneic tumors harboring Setd2 inactivation are sensitive to ICIs. By bulk and single-cell RNA-seq, we further reveal that SETD2 inactivation reprograms intratumoral immune cells and inflames the tumor microenvironment, which is characterized by high infiltration of T cells and enhanced antigen presentation to activate CD8+ T cell-mediated killing. Mechanistically, via an integrated multiomics analysis using ATAC-seq, ChIP-seq and RNA-seq, we demonstrate that SETD2 inactivation reduces NR2F1 transcription by impairing H3K36me3 deposition and chromatin accessibility, which activates the STAT1 signaling pathway to promote chemokines and programmed cell death protein-1 (PD-1) expression and enhance antigen presentation. All these regulatory mechanisms synergistically promote the effects of anti-programmed cell death ligand 1 immunotherapy in Setd2-knockout syngeneic mouse models. The SETD2-NR2F1-STAT1 regulatory axis is conserved in human and murine cancers. Finally, cancer patients harboring SETD2 mutations who received ICIs show increased durable clinical benefits and survival. CONCLUSIONS: These findings provide novel insights into the biology of SETD2 inactivation regulation and reveal a new potential therapeutic biomarker for ICIs immunotherapy in various refractory cancers.


Assuntos
Inibidores de Checkpoint Imunológico , Neoplasias , Humanos , Animais , Camundongos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Linfócitos T CD8-Positivos , Biomarcadores , Imunoterapia , Microambiente Tumoral , Fator I de Transcrição COUP/metabolismo , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo
3.
Int J Mol Sci ; 24(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36674734

RESUMO

Biomaterial-based nanofibrous scaffolds are the most effective alternative to bone transplantation therapy. Here, two recombinant minor ampullate spidroins (spider silk proteins), R1SR2 and NR1SR2C, were blended with Poly(lactic-co-glycolic) Acid (PLGA), respectively, to generate nanofiber scaffolds by electrospinning. The N-terminal (N), C-terminal (C), repeating (R1 and R2) and spacer (S) modules were all derived from the minor ampullate spidroins (MiSp). The physical properties and structures of the blended scaffolds were measured by scanning electron microscopy (SEM), water contact angle measurement, Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC), and Tensile mechanical testing. The results showed that blending of MiSp (R1SR2 and NR1SR2C) reduced the diameter of nanofibers, increased the porosity and glass transition temperatures of nanofibrous scaffolds, and effectively improved the hydrophilicity and ultimate strain of scaffolds. It is worth noting that the above changes were more significant in the presence of the N- and C-termini of MiSp. In cell culture assays, human bone mesenchymal stem cells (HBMSCs) grown on NR1SR2C/PLGA (20/80) scaffolds displayed markedly enhanced proliferative and adhesive abilities compared with counterparts grown on pure PLGA scaffolds. Jointly, these findings indicated recombinant MiSp/PLGA, particularly NR1SR2C/PLGA (20/80) blend nanofibrous scaffolds, is promising for bone tissue engineering.


Assuntos
Fibroínas , Nanofibras , Humanos , Engenharia Tecidual/métodos , Nanofibras/química , Alicerces Teciduais/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ácido Poliglicólico/química , Fibroínas/química , Glicóis , Ácido Láctico/química , Proliferação de Células , Proteínas dos Microfilamentos , Fosfoproteínas , Proteínas de Ciclo Celular
4.
J Exp Med ; 218(8)2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34143182

RESUMO

Central precocious puberty (CPP), largely caused by germline mutations in the MKRN3 gene, has been epidemiologically linked to cancers. MKRN3 is frequently mutated in non-small cell lung cancers (NSCLCs) with five cohorts. Genomic MKRN3 aberrations are significantly enriched in NSCLC samples harboring oncogenic KRAS mutations. Low MKRN3 expression levels correlate with poor patient survival. Reconstitution of MKRN3 in MKRN3-inactivated NSCLC cells directly abrogates in vitro and in vivo tumor growth and proliferation. MKRN3 knockout mice are susceptible to urethane-induced lung cancer, and lung cell-specific knockout of endogenous MKRN3 accelerates NSCLC tumorigenesis in vivo. A mass spectrometry-based proteomics screen identified PABPC1 as a major substrate for MKRN3. The tumor suppressor function of MKRN3 is dependent on its E3 ligase activity, and MKRN3 missense mutations identified in patients substantially compromise MKRN3-mediated PABPC1 ubiquitination. Furthermore, MKRN3 modulates cell proliferation through PABPC1 nonproteolytic ubiquitination and subsequently, PABPC1-mediated global protein synthesis. Our integrated approaches demonstrate that the CPP-associated gene MKRN3 is a tumor suppressor.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Proteína I de Ligação a Poli(A)/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Sequência de Aminoácidos , Animais , Carcinogênese/metabolismo , Carcinogênese/patologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Células HEK293 , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação/genética , Ligação Proteica , Biossíntese de Proteínas , Proteínas Proto-Oncogênicas p21(ras)/genética , Reprodutibilidade dos Testes , Análise de Sobrevida , Ubiquitina-Proteína Ligases/química , Ubiquitina-Proteína Ligases/deficiência , Ubiquitina-Proteína Ligases/genética , Uretana
5.
Cancer Res ; 81(9): 2481-2494, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33727226

RESUMO

Oncogenic KIT or PDGFRA receptor tyrosine kinase mutations are compelling therapeutic targets in gastrointestinal stromal tumor (GIST), and treatment with the KIT/PDGFRA inhibitor imatinib is the standard of care for patients with advanced GIST. Polyclonal emergence of KIT/PDGFRA secondary mutations is the main mechanism of imatinib progression, making it challenging to overcome KIT/PDGFRA-inhibitor resistance. It is unclear whether there are other therapeutic targets in advanced GIST. Using genome-wide transcriptomic profiling of advanced versus early-stage GIST and CRISPR knockout functional screens, we demonstrate that CDK1 is frequently highly expressed in advanced GIST but not in early-stage GIST across three patient cohorts. High expression of CDK1 was associated with malignancy in GIST. CDK1 was critically required for advanced GIST, including imatinib-resistant GIST. CDK1 ablation led to robust proliferation inhibition. A mass spectrometry-based proteomics screen further revealed that AKT is a novel substrate of CDK1 kinase in GIST. CDK1 bound AKT and regulated its phosphorylation, thereby promoting GIST proliferation and progression. Importantly, a pharmacologic inhibitor of CDK1, RO-3306, disrupted GIST cell proliferation in CDK1 highly expressed GIST but not in CDK1-negative GIST cells and nontransformed fibroblast cells. Treatment with RO-3306 reduced tumor growth in both imatinib-resistant and imatinib-sensitive GIST xenograft mouse models. Our findings suggest that CDK1 represents a druggable therapeutic target in GIST and warrants further testing in clinical trials. SIGNIFICANCE: These findings propose CDK1 as a novel cell-cycle-independent vulnerability in gastrointestinal stromal tumors, representing a new therapeutic opportunity for patients with advanced disease.


Assuntos
Antineoplásicos/administração & dosagem , Proteína Quinase CDC2/metabolismo , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/metabolismo , Mesilato de Imatinib/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Quinolinas/administração & dosagem , Tiazóis/administração & dosagem , Adulto , Idoso , Animais , Proteína Quinase CDC2/antagonistas & inibidores , Proteína Quinase CDC2/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/genética , Estudos de Coortes , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Tumores do Estroma Gastrointestinal/patologia , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Transfecção , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Cardiovasc Ther ; 2020: 3987065, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32411300

RESUMO

OBJECTIVE: The drug efficacy may differ among different statins, and evidence from head-to-head comparisons is sparse and inconsistent. The study is aimed at comparing the lipid-lowering/increasing effects of 7 different statins in patients with dyslipidemia, cardiovascular diseases, or diabetes mellitus by conducting systematic review and network meta-analyses (NMA) of the lipid changes after certain statins' use. METHODS: In this study, we searched four electronic databases for randomized controlled trials (RCTs) published through February 25, 2020, comparing the lipid-lowering efficacy of no less than two of the included statins (or statin vs. placebo). Three reviewers independently extracted data in duplicate. Firstly, mixed treatment overall comparison analyses, in the form of frequentist NMAs, were conducted using STATA 15.0 software. Then, subgroup analyses were conducted according to different baseline diseases. At last, sensitivity analyses were conducted according to age and follow-up duration. The trial was registered with PROSPERO (number CRD42018108799). RESULTS: As a result, seven statin monotherapy treatments in 50 studies (51956 participants) were used for the analyses. The statins included simvastatin (SIM), fluvastatin (FLU), atorvastatin (ATO), rosuvastatin (ROS), lovastatin (LOV), pravastatin (PRA), and pitavastatin (PIT). In terms of LDL-C lowering, rosuvastatin ranked 1st with a surface under cumulated ranking (SUCRA) value of 93.1%. The comparative treatment efficacy for LDL-C lowering was ROS>ATO>PIT>SIM>PRA>FLU>LOV>PLA. All of the other ranking and NMA results were reported in SUCRA plots and league tables. CONCLUSIONS: According to the NMAs, it can be concluded that rosuvastatin ranked 1st in LDL-C, ApoB-lowering efficacy and ApoA1-increasing efficacy. Lovastatin ranked 1st in TC- and TG-lowering efficacy, and fluvastatin ranked 1st in HDL-C-increasing efficacy. The results should be interpreted with caution due to some limitations in our review. However, they can provide references and evidence-based foundation for drug selection in both statin monotherapies and statin combination therapies.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Diabetes Mellitus/tratamento farmacológico , Dislipidemias/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Lipídeos/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus/sangue , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Regulação para Baixo , Dislipidemias/sangue , Dislipidemias/diagnóstico , Dislipidemias/epidemiologia , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Masculino , Pessoa de Meia-Idade , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Adulto Jovem
7.
J Exp Clin Cancer Res ; 39(1): 53, 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32293499

RESUMO

BACKGROUND: Epithelial ovarian cancer (EOC) is a highly lethal malignancy. Improvement in genetic characterization of EOC patients is required to propose new potential targets, since surgical resection coupled to chemotherapy, presents several limits such as cancer recurrence and drug resistance. Targeted therapies have more efficacy and less toxicity than standard treatments. One of the most relevant cancer-specific actionable targets are protein tyrosine kinases (PTKs) whose role in EOC need to be better investigated. METHODS: EOC genomic datasets are retrieved and analyzed. The biological and clinical significance of RET genomic aberrations in ovarian cancer context are investigated by a series of in vitro and in vivo experiments. RESULTS: Epithelial ovarian cancer sequencing projects identify recurrent genomic RET missense mutations in 1.98% of patients, ranking as the top-five hit among the 100 receptor tyrosine kinases-encoding genes. RET mutants R693H and A750T show oncogenic transformation properties in NIH3T3 cells. Introduction of the RET mutants into human EOC cells increases RET signaling, cell viability, anchorage-independent cell growth and tumor xenograft growth in nude mice, demonstrating that they are activating mutations. RET mutants significantly enhance the activation of RET and its downstream MAPK and AKT signaling pathway in ovarian cancer cells. Vandetanib, a clinical approved RET inhibitor, inhibits the cell viability and decreases the activation of RET-MAPK signaling pathways in EOC cells expressing oncogenic RET mutants. CONCLUSIONS: The discovery of RET pathogenic variants in the EOC patients, suggests a previously underestimated role for RET in EOC tumorigenesis. The identification of the gain-of-function RET mutations in EOC highlights the potential use of RET in targeted therapy to treat ovarian cancer patients.


Assuntos
Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/genética , Mutação , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Proteínas Proto-Oncogênicas c-ret/genética , Proteínas Proto-Oncogênicas c-ret/metabolismo , Animais , Carcinogênese , Carcinoma Epitelial do Ovário/enzimologia , Linhagem Celular Tumoral , Feminino , Células HEK293 , Humanos , Camundongos , Camundongos Nus , Terapia de Alvo Molecular , Células NIH 3T3 , Neoplasias Ovarianas/enzimologia , Inibidores de Proteínas Quinases/farmacologia , Transfecção
8.
Gastric Cancer ; 23(5): 837-847, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32291709

RESUMO

BACKGROUND: The majority of GISTs express mutationally activated KIT. Imatinib and sunitinib are approved KIT-inhibiting therapies. Their efficacy is usually hampered by the acquired multiple secondary drug-resistance KIT mutations. The most problematic resistance subset is GISTs with acquisition of secondary mutations in the KIT activation loop. Here, we establish the spectrum of activity of dasatinib against a comprehensive collection of clinically relevant KIT mutants associated with drug-sensitive and drug-resistant GIST. METHODS: The cellular and in vitro activities of tyrosine kinase inhibitors (TKIs) against mutant KIT were assessed using a panel of engineered and GIST-derived cell lines. The in vivo activities of dasatinib were determined using TKI-resistant xenograft models. RESULTS: In engineered and GIST-derived cell lines, dasatinib potently inhibited KIT with primary mutations in exon 11 or 9 and a range of secondary imatinib-resistant mutations in exons 13 and 14, encoding the ATP-binding pocket, and in exons 17 and 18, encoding the activation loop, with the exception of a substitution at codon T670. Our data show that dasatinib is more potent than imatinib or sunitinib at inhibiting the activity of drug-resistant KIT mutants. Dasatinib also induces regression in GIST-derived xenograft models containing these secondary mutations. A major determinant of the efficacy of dasatinib for the treatment of advanced GIST is the activity of this inhibitor against KIT mutants. CONCLUSION: Dasatinib shows efficacy in cancer models, inhibiting a wide range of oncogenic primary and drug-resistant KIT mutants. These results have implications for the further development of dasatinib precision therapy in GIST patients.


Assuntos
Dasatinibe/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Gastrointestinais/tratamento farmacológico , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Mutação , Proteínas Proto-Oncogênicas c-kit/genética , Animais , Antineoplásicos/farmacologia , Apoptose , Movimento Celular , Proliferação de Células , Feminino , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Clin Pharm Ther ; 45(5): 904-917, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32107837

RESUMO

OBJECTIVE: In patients with asthma and chronic obstructive pulmonary disease (COPD), disease control is still suboptimal-incorrect inhalation technique and medication non-adherence are two important reasons for this outcome. Pharmacists' interventions have been shown to have a positive effect on the clinical outcomes of asthma and COPD. Quantitative assessment of the efficacy of pharmacist-led interventions, mainly on inhalation techniques and medication adherence, is needed. Evidence for different interventions is not totally conclusive, and no results of theory-based adherence promotion interventions for asthma and COPD have been published. The objective of our study is to evaluate the effect of pharmacist-led interventions on asthma and COPD management, focusing mainly on inhalation technique and medication adherence, and whether the content of interventions (categorized based on Information-Motivation-Behavioural skills (IMB) model) affects the effectiveness and whether the IMB model is worthy of clinical promotion and application in adults with asthma or COPD. METHODS: The PubMed, EMBASE, The Cochrane Library, Web of Science and ClinicalTrials.gov databases were searched for randomized controlled trials that involved pharmacist-led interventions among patients with asthma or COPD. We used database-specific vocabulary (eg, Medical Subject Headings) and free text terms expanding from 'asthma', 'COPD' and 'pharmacist' to identify relevant articles. Two reviewers independently selected the studies, assessed the risk of bias and extracted the data. The meta-analysis was performed in Review Manager 5.3 provided by the Cochrane Collaboration. PROSPERO registration number: CRD42019144793. RESULTS AND DISCUSSION: Thirteen studies were eligible for qualitative analysis, and 12 studies were included in the meta-analysis. Pharmacist-led interventions showed a positive effect on medication adherence (1.34 [95% CI 1.18-1.53], P < .0001) and inhalation technique (1.85 [95% CI 1.57-2.17], P < .00001) in COPD and asthma patients. In the subgroup meta-analysis, significant medication adherence improvement was found only in COPD patients (1.41 [1.24-1.61], P < .0001). The subgroup meta-analysis also noted that interventions that included all three Information-Motivation-Behavioural skills (IMB) constructs had a significant improvement in medication adherence (1.41 [1.24-1.61], P < .0001). Subgroup meta-analysis conducted between different diseases, different intervention contents, and different measure tools did not significantly change the heterogeneity. WHAT IS NEW AND CONCLUSION: Pharmacist-led interventions can improve inhalation technique in adult asthma and COPD patients. Significant improvement in medication adherence was found only in COPD patients. The effect among asthmatic patients requires further study. Interventions based on the IMB model may be worthy of clinical promotion and application. More future research is needed to establish solid evidence base for effective interventions and uniform measurement of medication adherence.


Assuntos
Asma/tratamento farmacológico , Farmacêuticos/organização & administração , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Administração por Inalação , Adulto , Humanos , Adesão à Medicação/estatística & dados numéricos , Assistência Farmacêutica/organização & administração , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Carcinogenesis ; 41(1): 44-55, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-31046123

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with few therapeutic options, representing one of the great challenges in oncology. Activating KRAS mutation, occurring in >90% PDACs, is present in pancreatic intraepithelial neoplasia lesions, the precursor ductal lesions of PDAC, indicating additional genetic alterations contribute to the pathogenesis of PDAC. PDAC sequencing projects identify recurrent genomic ERBB2 alterations, mutations and amplifications, in 8.5% of PDAC patients, ranking as the top hit among the 100 receptor tyrosine kinases-encoding genes. Introduction of the ERBB2 mutations encoding protein variants S310F, S423R, R678Q, Q679L, E717D, L755S, V777L and V842I into human pancreatic epithelial cells causes oncogenic transformation, increasing ERBB2 signaling, anchorage-independent cell growth and tumor xenograft growth in nude mice, demonstrating that they are activating mutations. Interestingly, in many PDACs, mutations in ERBB2 and KRAS occur together. ERBB2 activating mutants facilitate KRAS-driven oncogenic properties. Introduction of ERBB2 mutations into KRAS-mutant PDAC cells activates ERBB2 signaling, promotes tumor growth and attenuates KRAS dependency. In contrast, a CRISPR-mediated knockout (KO) of ERBB2 in ERBB2-amplified PDAC cells inhibits ERBB2 signaling, colony formation, anchorage-independent growth and tumor xenograft formation. Finally, oncogenic ERBB2 aberrations can be abrogated by treatment with small-molecule inhibitors. ERBB2 and KRAS inhibition cooperate to suppress PDAC cell growth in vitro and to promote tumor regression in nude mice, providing a rationale for testing an anti-ERBB2 drug in combination with a KRAS inhibitor in ERBB2-mutant PDAC patients that are currently untreatable.


Assuntos
Carcinoma Ductal Pancreático/genética , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Receptor ErbB-2/genética , Animais , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Variações do Número de Cópias de DNA , Conjuntos de Dados como Assunto , Progressão da Doença , Sinergismo Farmacológico , Técnicas de Inativação de Genes , Células HEK293 , Humanos , Masculino , Camundongos , Mutagênese Sítio-Dirigida , Mutação , Ductos Pancreáticos/patologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Receptor ErbB-2/antagonistas & inibidores , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Asian Nat Prod Res ; 22(5): 496-502, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31738087

RESUMO

Bistachybotrysin K (1), one new phenylspirodrimane dimer with a central 6/7 oxygen heterocycle core, was isolated from the fungus Stachybotrys chartarum CGMCC 3.5365. Its structure was elucidated by extensive spectroscopic data and single-crystal X-ray diffraction. Compound 1 showed significant cytotoxicity against human tumor cell lines HCT116, NCI-H460, BGC823, Daoy, and HepG2 with IC50 values in the range of 1.1-4.7 µM.


Assuntos
Antineoplásicos , Compostos de Espiro , Stachybotrys , Linhagem Celular Tumoral , Humanos , Estrutura Molecular
12.
Proc Natl Acad Sci U S A ; 116(45): 22746-22753, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31636198

RESUMO

Gastrointestinal stromal tumors (GISTs) are the most common human sarcoma and are initiated by activating mutations in the KIT or PDGFRA receptor tyrosine kinases. Chromosome 22q deletions are well-recognized frequent abnormalities in GISTs, occurring in ∼50% of GISTs. These deletions are thought to contribute to the pathogenesis of this disease via currently unidentified tumor suppressor mechanisms. Using whole exome sequencing, we report recurrent genomic inactivated DEPDC5 gene mutations in GISTs (16.4%, 9 of 55 patients). The demonstration of clonal DEPDC5 inactivation mutations in longitudinal specimens and in multiple metastases from individual patients suggests that these mutations have tumorigenic roles in GIST progression. DEPDC5 inactivation promotes GIST tumor growth in vitro and in nude mice. DEPDC5 reduces cell proliferation through the mTORC1-signaling pathway and subsequently induces cell-cycle arrest. Furthermore, DEPDC5 modulates the sensitivity of GIST to KIT inhibitors, and the combination therapy with mTOR inhibitor and KIT inhibitor may work better in GIST patients with DEPDC5 inactivation. These findings of recurrent genomic alterations, together with functional data, validate the DEPDC5 as a bona fide tumor suppressor contributing to GIST progression and a biologically relevant target of the frequent chromosome 22q deletions.


Assuntos
Proteínas Ativadoras de GTPase/genética , Neoplasias Gastrointestinais/genética , Tumores do Estroma Gastrointestinal/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Mutação , Animais , Deleção Cromossômica , Cromossomos Humanos Par 22 , Progressão da Doença , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/patologia , Xenoenxertos , Humanos , Sequenciamento do Exoma
13.
Adv Prev Med ; 2019: 8392348, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31093375

RESUMO

BACKGROUND AND OBJECTIVE: Current cardiovascular disease (CVD) risk models are typically based on traditional laboratory-based predictors. The objective of this research was to identify key risk factors that affect the CVD risk prediction and to develop a 10-year CVD risk prediction model using the identified risk factors. METHODS: A Cox proportional hazard regression method was applied to generate the proposed risk model. We used the dataset from Framingham Original Cohort of 5079 men and women aged 30-62 years, who had no overt symptoms of CVD at the baseline; among the selected cohort 3189 had a CVD event. RESULTS: A 10-year CVD risk model based on multiple risk factors (such as age, sex, body mass index (BMI), hypertension, systolic blood pressure (SBP), cigarettes per day, pulse rate, and diabetes) was developed in which heart rate was identified as one of the novel risk factors. The proposed model achieved a good discrimination and calibration ability with C-index (receiver operating characteristic (ROC)) being 0.71 in the validation dataset. We validated the model via statistical and empirical validation. CONCLUSION: The proposed CVD risk prediction model is based on standard risk factors, which could help reduce the cost and time required for conducting the clinical/laboratory tests. Healthcare providers, clinicians, and patients can use this tool to see the 10-year risk of CVD for an individual. Heart rate was incorporated as a novel predictor, which extends the predictive ability of the past existing risk equations.

14.
Fitoterapia ; 136: 104158, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31051194

RESUMO

Bistachybotrysins F-J (1-5), five new phenylspirodrimane dimers with a central cyclopentanone core were isolated from Stachybotrys chartarum CGMCC 3.5365. The structures of 1-5 were elucidated through extensive spectroscopic data analysis, including 1D/2D NMR, HR-MS, and ECD spectra. Compounds 3-5 displayed moderate cytotoxic activity against the cell lines HCT116, NCI-H460, and HepG2 with IC50 values ranging from 9.1 to 12.2 µM, making them promising as lead compounds for drug research and discovery.


Assuntos
Compostos de Espiro/farmacologia , Stachybotrys/química , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Compostos de Espiro/química
15.
J Asian Nat Prod Res ; 21(9): 887-894, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30614271

RESUMO

Three new phenylspirodrimanes derivatives named stachybotrysins H and I (1 and 2) and stachybotrin E (3), together with one known compound stachybotrylactam (4), were isolated from Stachybotrys chartarum CGMCC 3.5365. Their structures were determined by extensive NMR data and mass spectroscopic analysis. Compounds 1 and 2 showed inhibitory effect towards potassium channel Kv1.3 with IC50 values of 13.4 and 10.9 µM, respectively.


Assuntos
Canal de Potássio Kv1.3/antagonistas & inibidores , Compostos de Espiro/química , Stachybotrys/química , Animais , Células CHO , Linhagem Celular , Cricetinae , Cricetulus
16.
Oncotarget ; 8(36): 60589-60604, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28947997

RESUMO

Gastrointestinal stromal tumors (GISTs) are the most common sarcomas in humans. Constitutively activating mutations in the KIT or PDGFRA receptor tyrosine kinases are the initiating oncogenic events. Most metastatic GISTs respond dramatically to therapies with KIT/PDGFRA inhibitors. Asymptomatic and mitotically-inactive KIT/PDGFRA-mutant "microGISTs" are found in one third of adults, but most of these small tumors never progress to malignancy, underscoring that a progression of oncogenic mutations is required. Recent studies have identified key genomic abnormalities in GIST progression. Novel insights into the genetic progression of GISTs are shedding new light on therapeutic innovations.

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