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1.
J Org Chem ; 89(2): 1209-1219, 2024 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-38192075

RESUMO

Guided by the Global Natural Products Social (GNPS) molecular networking strategy, five undescribed eremophilane-type sesquiterpenoid derivatives (1-5) were isolated and identified from fungus Penicillium roqueforti, which was separated from the root soil of plant Hypericum beanii collected in Shennongjia Forestry District, Hubei Province. Dipeniroqueforins A-B (1-2), representing a lactam-type sesquiterpenoid skeleton with a highly symmetrical and homodimeric 5/6/6-6/6/5 hexacyclic system, are reported within the eremophilane-type family for the first time. Peniroqueforin D (5) represents the first example of a 1,2-seco eremophilane-type sesquiterpenoid derivative featuring an undescribed 7/6-fused ring system. The structures of these compounds were elucidated by various spectroscopic analyses, DP4+ probability analyses, ECD calculations, and single-crystal X-ray diffraction experiments. Furthermore, these isolates were evaluated for cytotoxicity, and the result uncovered that compound 1 displayed broad-spectrum activity. Further mechanistic study revealed that compound 1 could significantly upregulate the mRNA expression of genes related to the oxidative induction, leading to the abnormal ROS levels in tumor cells and ultimately causing tumor cell apoptosis.


Assuntos
Antineoplásicos , Penicillium , Sesquiterpenos , Sesquiterpenos Policíclicos , Estrutura Molecular , Sesquiterpenos/química , Penicillium/química , Antineoplásicos/química
2.
Clin Lymphoma Myeloma Leuk ; 24(4): 260-268.e2, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38216397

RESUMO

INTRODUCTION: Azacitidine (AZA) is an approved frontline therapy for higher-risk myelodysplastic syndromes (HR-MDS); however, poor survival denotes unmet needs to increase depth/duration of response (DOR). METHODS: This retrospective study with patient chart review evaluated AZA effectiveness in 382 treatment-naive patients with HR-MDS from a US electronic health record (EHR)-derived database. Responses were assessed using International Working Group (IWG) 2006 criteria; real-world equivalents were derived from EHRs. Primary endpoint was IWG 2006-based complete remission rate (CRR). Secondary endpoints were EHR-based CRR, IWG 2006- and EHR-based objective response rates (ORRs), duration of CR, DOR, progression-free survival, time-to-next-treatment, and overall survival (OS). RESULTS: Using IWG 2006 criteria, the CRR was 7.9% (n = 30); median duration of CR was 12.0 months (95% CI, 7.7-15.6). In poor cytogenetic risk (n = 101) and TP53 mutation (n = 46) subgroups, CRRs were 7.9% (n = 8) and 8.7% (n = 4), respectively. ORR was 62.8% (n = 240), including a hematologic improvement rate (HIR) of 46.9% (n = 179). Using EHR-based data, CRR was 3.7% (n = 14); median duration of CR was 13.5 months (95% CI, 4.5-21.5). ORR was 67.8% (n = 259), including an HIR of 29.3% (n = 112). Median follow-up was 12.9 months; median OS was 17.9 months (95% CI, 15.5-21.7). CONCLUSIONS: Consistent with other studies, CRRs and median OS with AZA in treatment-naive patients with HR-MDS were low in this large, real-world cohort. Novel agents/combinations are urgently needed to improve these outcomes in HR-MDS.


Assuntos
Azacitidina , Síndromes Mielodisplásicas , Humanos , Azacitidina/farmacologia , Azacitidina/uso terapêutico , Antimetabólitos Antineoplásicos/farmacologia , Antimetabólitos Antineoplásicos/uso terapêutico , Síndromes Mielodisplásicas/genética , Estudos Retrospectivos , Mutação , Resultado do Tratamento
3.
Nat Prod Bioprospect ; 13(1): 17, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37261606

RESUMO

Two novel compounds including a cyclohelminthol type polyketide (namely oxaleimide K, 1) and a maleimide derivative (namely peniroquefortine A, 2), and a new natural product (namely 2-(acetylamino)-N-[(1E)-2-phenylethenyl]-acetamide, 3), together with four known compounds (4-7), were isolated and identified from fungus Penicillium roqueforti, which was separated from the root soil of Hypericum beanii N. Robson collected from the Shennongjia Forestry District, Hubei Province. Their structures including absolute configurations were mainly established by the NMR spectroscopy analyses and single-crystal X-ray diffraction experiment. Compound 1 represents the second example of a cyclohelminthol type polyketide, which features a rare 6/6/5/5 tetracyclic system and a branched aliphatic chain containing a terminal olefin (oct-1-en-3-yl) moiety, and compound 2 possesses an unprecedented carbon skeleton that is uniquely defined by a maleimide moiety linked to the respective 4-methylene-2-(3-methylbut-2-en-1-yl)-phenol and para-substituted aromatic moieties via the carbon-carbon bonds. Remarkably, the absolute configuration of a cyclohelminthol type polyketide as exemplified by compound 1 is determined by the single-crystal diffraction analysis for the first time, highlighting an E-configuration for the linkage of a succinimide moiety and a tetrahydrofuran moiety for 1 rather than a Z-configuration as previously reported in the biosynthesis study, which gives a new insight into the structural elucidation of this category of polyketides. Additionally, compound 1 exhibited significant cytotoxic activity against multiple tumor cells, especially against the Farage and SU-DHL-2 cells (IC50 < 20 µM, 48 h). Further mechanism study revealed that compound 1 significantly induced cell cycle arrest in Farage and SU-DHL-2 cells by causing abnormal ROS level and triggering oxidative stress.

4.
Phytochemistry ; 212: 113722, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37230212

RESUMO

Nine undescribed eremophilane sesquiterpenes, one undescribed guaiane sesquiterpene, along with ten known analogues were isolated and identified from fungus Penicillium roqueforti, which was separated from the root soil of Hypericum beanii N. Robson collected from the Shennongjia Forestry District, Hubei Province. Their structures were elucidated on the basis of various spectroscopic analyses, mainly including NMR and HRESIMS data, 13C NMR calculations with DP4+ probability analyses, ECD calculations, and single-crystal X-ray diffraction experiments. Furthermore, all twenty compounds were evaluated for the in vitro cytotoxic activities against seven human tumor cell lines, and the result suggested that 14-hydroxymethylene-1(10)-ene-epi-guaidiol A exhibited considerable cytotoxic activity against the Farage (IC50 < 10 µM, 48 h), SU-DHL-2, and HL-60 cells. Further mechanism study demonstrated that 14-hydroxymethylene-1(10)-ene-epi-guaidiol A could significantly promote apoptosis by inhibiting tumor cell respiration and decreasing intracellular ROS levels, thereby inducing S-phase blockade in tumor cells.


Assuntos
Penicillium , Sesquiterpenos , Humanos , Sesquiterpenos Policíclicos , Sesquiterpenos de Guaiano , Estrutura Molecular , Sesquiterpenos/química , Penicillium/química
5.
Bioorg Chem ; 127: 105988, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35797862

RESUMO

Fifteen secondary metabolites, including five new sesquiterpenoids (1-5), one new benzofuranoid (10), one new ophiobolin sesterterpenoid (11), and one new 3,5-dimethylorsellinic acid (DMOA)-based meroterpenoid (15), as well as seven known analogues (6-9 and 12-14), were isolated and characterized from fungus Aspergillus calidoustus, which was separated from the wetland soil collected at Dianchi Lake, Yunnan Province. Compound 5 featured an unusual dioxolane moiety, and compound 15 was a rare austin meroterpenoid analogue with the opened A ring, and also featured an undescribed oxygen bridge between C-3 and C-16 to construct an unexpected tetrahydrofuran ring. Their structures were established by widespread spectroscopic methods, single-crystal X-ray diffraction experiments, and ECD calculation. All the isolated drimane sesquiterpenoids were evaluated for the in vitro cytotoxicity against five tumor cell lines, including SW480 (colon cancer), IOMM-Lee (meningioma), HeLa (cervical cancer), FARAGE (diffuse large B-cell lymphoma), and SU-DHL-4 (diffuse large B-cell lymphoma). Compound 9 exhibited significant cytotoxicity against FARAGE and SU-DHL-4 tumor cell lines with IC50 values of 5.54 and 9.78 µM, respectively. Further mechanism study showed that 9 could significantly promote apoptosis in FARAGE and SU-DHL-4 cell lines by interfering with mitochondrial function.


Assuntos
Linfoma Difuso de Grandes Células B , Sesquiterpenos , Aspergillus , China , Fungos , Humanos , Estrutura Molecular , Sesquiterpenos/química , Solo
6.
Nat Prod Res ; 36(2): 531-538, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32643425

RESUMO

A new abietane-type diterpenoid, dalterpenoid A (1), a new long-chain alkenone derivative, (3E,5E,10E)-8-hydroxytrideca-3,5,10,12-tetraen-2-one (2), together with six known compounds (3-8), namely epi-guaidiol A (3), xylaranol A (4), daldinone C (5), trans-3,4-dihydroxy-3,4-dihydro-anofinic acid (6), (R)-6-hydroxymellein (7), helicascolide A (8), were obtained from fungus Daldinia sp. TJ403-LS1, which was originally isolated from roots of the medicinally valuable plant Anoectochilus roxburghii. The structures of compounds 1 and 2 were established based on widespread spectroscopic methods, mainly including 1D & 2D NMR and HRESIMS analyses, and the absolute configuration of 1 was further confirmed by electronic circular dichroism (ECD) calculation. All new compounds were tested for the in vitro cytotoxicity against five human cancer cell lines.


Assuntos
Diterpenos , Xylariales , Abietanos/farmacologia , Dicroísmo Circular , Diterpenos/farmacologia , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular
7.
Phytochemistry ; 190: 112892, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34343886

RESUMO

Large-scale culture is a complementary and practical method for genome mining and OSMAC approaches to discover novel natural products through accumulation and reprocessing effects. By employing a large-scale culture approach, twelve 3,5-dimethylorsellinic acid (DMOA)-based meroterpenoids, including five undescribed compounds, namely asperanstinoids A-E, were obtained from fungus Aspergillus calidoustus, which was isolated from the wetland soil collected at Dianchi Lake, Yunnan Province. The structures and absolute configurations of asperanstinoids A-E were determined by various spectroscopic analyses, including NMR spectroscopy, high-resolution electrospray ionization mass spectrometry (HRESIMS), single-crystal X-ray diffraction, and electronic circular dichroism (ECD) calculations, and the absolute configurations of three known compounds, dehydroaustinol, austinol, and austin, were confirmed via single-crystal X-ray diffraction for the first time. Notably, asperanstinoid A represents the second example of a DMOA-based meroterpenoid featuring a unique 6/5/6/6/6/5-fused hexacyclic skeleton with a rare "1,13-epoxy" moiety. The cytotoxicity assay of all these isolates revealed that asperanstinoid D, dehydroaustinol, and austin displayed considerable cytotoxicity against the HL-60 and SU-DHL-4 tumor cell lines with IC50 values ranging from 15.7 to 27.8 µM.


Assuntos
Aspergillus , China , Dicroísmo Circular , Resorcinóis
8.
J Hepatol ; 73(6): 1368-1378, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32707225

RESUMO

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is the leading cause of death in patients with chronic hepatitis. In this international collaboration, we sought to develop a global universal HCC risk score to predict the HCC development for patients with chronic hepatitis. METHODS: A total of 17,374 patients, comprising 10,578 treated Asian patients with chronic hepatitis B (CHB), 2,510 treated Caucasian patients with CHB, 3,566 treated patients with hepatitis C virus (including 2,489 patients with cirrhosis achieving a sustained virological response) and 720 patients with non-viral hepatitis (NVH) from 11 international prospective observational cohorts or randomised controlled trials, were divided into a training cohort (3,688 Asian patients with CHB) and 9 validation cohorts with different aetiologies and ethnicities (n = 13,686). RESULTS: We developed an HCC risk score, called the aMAP score (ranging from 0 to 100), that involves only age, male, albumin-bilirubin and platelets. This metric performed excellently in assessing HCC risk not only in patients with hepatitis of different aetiologies, but also in those with different ethnicities (C-index: 0.82-0.87). Cut-off values of 50 and 60 were best for discriminating HCC risk. The 3- or 5-year cumulative incidences of HCC were 0-0.8%, 1.5-4.8%, and 8.1-19.9% in the low- (n = 7,413, 43.6%), medium- (n = 6,529, 38.4%), and high-risk (n = 3,044, 17.9%) groups, respectively. The cut-off value of 50 was associated with a sensitivity of 85.7-100% and a negative predictive value of 99.3-100%. The cut-off value of 60 resulted in a specificity of 56.6-95.8% and a positive predictive value of 6.6-15.7%. CONCLUSIONS: This objective, simple, reliable risk score based on 5 common parameters accurately predicted HCC development, regardless of aetiology and ethnicity, which could help to establish a risk score-guided HCC surveillance strategy worldwide. LAY SUMMARY: In this international collaboration, we developed and externally validated a simple, objective and accurate prognostic tool (called the aMAP score), that involves only age, male, albumin-bilirubin and platelets. The aMAP score (ranged from 0 to 100) satisfactorily predicted the risk of hepatocellular carcinoma (HCC) development among over 17,000 patients with viral and non-viral hepatitis from 11 global prospective studies. Our findings show that the aMAP score had excellent discrimination and calibration in assessing the 5-year HCC risk among all the cohorts irrespective of aetiology and ethnicity.


Assuntos
Carcinoma Hepatocelular , Saúde Global/estatística & dados numéricos , Hepatite Crônica , Neoplasias Hepáticas , Medição de Risco/métodos , Antivirais/uso terapêutico , Povo Asiático/estatística & dados numéricos , Bilirrubina/análise , Plaquetas/patologia , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Feminino , Hepatite Crônica/sangue , Hepatite Crônica/complicações , Hepatite Crônica/diagnóstico , Hepatite Crônica/etnologia , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco , Albumina Sérica/análise , População Branca/estatística & dados numéricos
9.
Org Biomol Chem ; 17(22): 5526-5532, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-31041978

RESUMO

Marine-derived fungi have been regarded as an under-explored and promising reservoir of structurally novel and bioactive natural products. In this study, five new γ-pyrone-containing polyketides, fusaresters A-E (1-5), were isolated and identified from the culture extracts of a marine-derived fungus Fusarium sp. Hungcl. The structures of compounds 1-5 were elucidated on the basis of their HRESIMS and NMR spectroscopic data as well as 13C NMR calculation and electronic circular dichroism (ECD) analyses. Remarkably, the structure of fusariumin D was revised to (9S*,11S*)-3. All these isolates were tested for the cytotoxicity against seven human cancer cell lines, including SW480, HL-60, A549, MCF-7, HepG2, HeLa and SMMC-7721, and the inhibitory activity against protein tyrosine phosphatase 1B (PTP1B). The results revealed that only compound 2 showed a weak inhibition rate of 56% at 40 µM.


Assuntos
Cumarínicos/química , Fusarium/química , Policetídeos/isolamento & purificação , Pironas/isolamento & purificação , Estrutura Molecular , Policetídeos/química , Pironas/química
10.
Lancet Oncol ; 16(5): 550-60, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25882987

RESUMO

BACKGROUND: Nilotinib inhibits the tyrosine kinase activity of ABL1/BCR-ABL1 and KIT, platelet-derived growth factor receptors (PDGFRs), and the discoidin domain receptor. Gain-of-function mutations in KIT or PDGFRα are key drivers in most gastrointestinal stromal tumours (GISTs). This trial was designed to test the efficacy and safety of nilotinib versus imatinib as first-line therapy for patients with advanced GISTs. METHODS: In this randomised, open-label, multicentre, phase 3 trial (ENESTg1), participants from academic centres were aged 18 years or older and had previously untreated, histologically confirmed, metastatic or unresectable GISTs. Patients were stratified by previous adjuvant therapy and randomly assigned (1:1) via a randomisation list to receive oral imatinib 400 mg once daily or oral nilotinib 400 mg twice daily. The primary endpoint was centrally reviewed progression-free survival. Efficacy endpoints were assessed by intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT00785785. FINDINGS: Because the futility boundary was crossed at a preplanned interim analysis, trial accrual terminated in April, 2011. Between March 16, 2009, and April 21, 2011, 647 patients were enrolled; of whom 324 were allocated nilotinib and 320 were allocated imatinib. At final analysis of the core study (data cutoff, October, 2012), 2-year progression-free survival was higher in the imatinib group (59·2% [95% CI 50·9-66·5]) than in the nilotinib group (51·6% [43·0-59·5]; hazard ratio 1·47 [95% CI 1·10-1·95]). In the imatinib group, the most common grade 3-4 adverse events were hypophosphataemia (19 [6%]), anaemia (17 [5%]), abdominal pain (13; 4%), and elevated lipase level (15; 5%), and in the nilotinib group were anaemia (18; 6%), elevated lipase level (15; 5%), elevated alanine aminotransferase concentration (12; 4%), and abdominal pain (11; 3%). The most common serious adverse event in both groups was abdominal pain (11 [4%] in the imatinib group, 14 [4%] in the nilotinib group). INTERPRETATION: Nilotinib cannot be recommended for broad use to treat first-line GIST. However, future studies might identify patient subsets for whom first-line nilotinib could be of clinical benefit. FUNDING: Novartis Pharmaceuticals.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Benzamidas/administração & dosagem , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Piperazinas/administração & dosagem , Pirimidinas/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Tumores do Estroma Gastrointestinal/patologia , Humanos , Mesilato de Imatinib , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Resultado do Tratamento
11.
Lifetime Data Anal ; 21(2): 218-40, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25053470

RESUMO

Sometimes in clinical trials, the hazard rates are anticipated to be nonproportional, resulting in potentially crossing survival curves. In these cases, researchers are usually interested in which treatment has better long-term survival. The log-rank test and the weighted log-rank test may not be appropriate or efficient to use here, because they are sensitive to differences in survival at any time and don't just focus on long-term outcomes. Also in a prospective clinical trial, patients are entered sequentially over calendar time, so that group sequential designs may be considered for ethical, administrative and economic concerns. Here we develop group sequential methods for testing the null hypothesis that the survival curves are identical after a prespecified time point. Several classes of tests are considered, including an integrated difference in survival probabilities after this time point, and linear or quadratic combinations of two component test statistics (pointwise comparisons of survival at the time point and comparisons of hazard rates after the time point). We examine the type I errors, stopping probabilities, and powers of these tests through simulation studies under the null and different alternatives, and we apply them to a real bone marrow transplant clinical trial.


Assuntos
Biometria/métodos , Modelos Estatísticos , Análise de Sobrevida , Viés , Transplante de Medula Óssea , Ensaios Clínicos como Assunto , Simulação por Computador , Humanos , Modelos Lineares , Método de Monte Carlo , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia
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