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1.
Neurooncol Pract ; 11(3): 336-346, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38737615

RESUMO

Background: Biomarker-based therapies are increasingly used in cancer patients outside clinical trials. Systematic assessment of patient-reported outcomes (PRO) is warranted to take patients' perspectives during biomarker-based therapies into consideration. We assessed the feasibility of an electronic PRO assessment via a smartphone application. Methods: An interdisciplinary expert panel developed a smartphone application based on symptom burden and health-related quality of life (HRQoL) metrics reported in a retrospective analysis of 292 neuro-oncological patients. The app included validated assessments of health-related quality of life (HRQoL), the burden of symptoms, and psychological stress. Feasibility and usability were tested in a pilot study. Semi-structured interviews with patients and health care professionals (HCP) were conducted, transcribed, and analyzed according to Mayring´s qualitative content analysis. Furthermore, we assessed compliance and descriptive data of ePROs. Results: A total of 14 patients have been enrolled, (9 female, 5 male). A total of 4 HCPs, 9 patients, and 1 caregiver were interviewed regarding usability/feasibility. The main advantages were the possibility to complete questionnaires at home and comfortable implementation in daily life. Compliance was high, for example, 82% of the weekly distributed NCCN distress thermometer questionnaires were answered on time, however, with interindividual variability. We observed a median distress score of 5 (range 0-10, 197 results, n = 12, weekly assessed) and a median Global health score of 58.3 according to the EORTC QLQ-C30 instrument (range 16.7-100, 77 results, n = 12, monthly assessed). Conclusions: This pilot study proved the feasibility and acceptance of the app. We will therefore expand its application during biomarker-guided therapies to enable systematic PRO assessments.

2.
Cancers (Basel) ; 16(8)2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38672572

RESUMO

Breast cancer is the leading cause of cancer-related mortality among women in Germany and worldwide. This retrospective claims data analysis utilizing data from AOK Baden-Wuerttemberg, a major statutory German health insurance provider, aimed to construct and assess a real-world data breast cancer disease model. The study included 27,869 female breast cancer patients and 55,738 age-matched controls, analyzing data from 2010 to 2020. Three distinct breast cancer stages were analyzed: Stage A (early breast cancer without lymph node involvement), Stage B (early breast cancer with lymph node involvement), and Stage C (primary distant metastatic breast cancer). Tumor subtypes were estimated based on the prescription of antihormonal or HER2-targeted therapy. The study established that 77.9% of patients had HR+ breast cancer and 9.8% HER2+; HR+/HER2- was the most common subtype (70.9%). Overall survival (OS) analysis demonstrated significantly lower survival rates for stages B and C than for controls, with 5-year OS rates ranging from 79.3% for stage B to 35.4% for stage C. OS rates were further stratified by tumor subtype and stage, revealing varying prognoses. Distant recurrence-free survival (DRFS) analysis showed higher recurrence rates in stage B than in stage A, with HR-/HER2- displaying the worst DRFS. This study, the first to model breast cancer subtypes, stages, and outcomes using German claims data, provides valuable insights into real-world breast cancer epidemiology and demonstrates that this breast cancer disease model has the potential to be representative of treatment outcomes.

3.
Eur J Cancer ; 188: 111-121, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37229835

RESUMO

BACKGROUND: Assessments of health-related quality of life (HRQoL) play an important role in transition to palliative care for women with metastatic breast cancer. We developed machine learning (ML) algorithms to analyse longitudinal HRQoL data and identify patients who may benefit from palliative care due to disease progression. METHODS: We recruited patients from two institutions and administered the EuroQoL Visual Analog Scale (EQ-VAS) via an online platform over a 6-month period. We trained a regularised regression algorithm using 10-fold cross-validation to determine if a patient was at high or low risk of disease progression based on changes in the EQ-VAS scores using data of one institution and validated the performance on data of the other institution. Progression-free survival (PFS) was the end-point. We conducted Kaplan-Meier and Cox regression analysis adjusted for clinical risk factors. RESULTS: Of 179 patients, 98 (54.7%) had progressive disease after a median follow-up of 14weeks. Using EQ-VAS scores collected at weeks 1-6 to predict disease progression at week 12, in the validation set (n = 63), PFS was significantly lower in the intelligent EQ-VAS high-risk versus low-risk group: median PFS 7 versus 10weeks, log-rank P < 0.038). Intelligent EQ-VAS had the strongest association with PFS (adjusted hazard ratio 2.69, 95% confidence interval 1.17-6.18, P = 0.02). CONCLUSION: ML algorithms can analyse changes in longitudinal HRQoL data to identify patients with disease progression earlier than standard follow-up methods. Intelligent EQ-VAS scores were identified as independent prognostic factor. Future studies may validate these results to remotely monitor patients.


Assuntos
Neoplasias da Mama , Qualidade de Vida , Humanos , Feminino , Estudos Retrospectivos , Neoplasias da Mama/terapia , Neoplasias da Mama/patologia , Progressão da Doença , Medidas de Resultados Relatados pelo Paciente , Inquéritos e Questionários
4.
ACS Chem Biol ; 17(3): 576-589, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35262340

RESUMO

Protease inhibitors represent a promising therapeutic option for the treatment of parasitic diseases such as malaria and human African trypanosomiasis. Falcitidin was the first member of a new class of inhibitors of falcipain-2, a cysteine protease of the malaria parasite Plasmodium falciparum. Using a metabolomics dataset of 25 Chitinophaga strains for molecular networking enabled identification of over 30 natural analogues of falcitidin. Based on MS/MS spectra, they vary in their amino acid chain length, sequence, acyl residue, and C-terminal functionalization; therefore, they were grouped into the four falcitidin peptide families A-D. The isolation, characterization, and absolute structure elucidation of two falcitidin-related pentapeptide aldehyde analogues by extensive MS/MS spectrometry and NMR spectroscopy in combination with advanced Marfey's analysis was in agreement with the in silico analysis of the corresponding biosynthetic gene cluster. Total synthesis of chosen pentapeptide analogues followed by in vitro testing against a panel of proteases revealed selective parasitic cysteine protease inhibition and, additionally, low-micromolar inhibition of α-chymotrypsin. The pentapeptides investigated here showed superior inhibitory activity compared to falcitidin.


Assuntos
Antimaláricos , Cisteína Proteases , Malária , Parasitos , Animais , Antimaláricos/farmacologia , Inibidores de Cisteína Proteinase/química , Inibidores de Cisteína Proteinase/farmacologia , Humanos , Plasmodium falciparum , Espectrometria de Massas em Tandem
5.
Chemistry ; 26(56): 12738-12742, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-32716576

RESUMO

Hydrogen isotopically labelled compounds are essential diagnostic tools in drug research and development, as they provide vital information about the biological metabolism of drug candidates and their metabolites. Herein we report a photoredox-initiated hydrogen atom transfer (HAT) protocol which efficiently and selectively introduces deuterium or tritium at C(sp3 )-H bonds, utilizing heavy water (D2 O or T2 O) as the hydrogen isotope source, and a guanidine base. This protocol has been successfully applied to the incorporation of deuterium in several amino acids (lysine, glycine and proline) and small peptides. Finally, the method has been applied to tritium, because tritium-labelled peptides are essential for application in biological experiments, such as ligand-binding assays, or absorption, distribution, metabolism, and excretion (ADME) studies.


Assuntos
Preparações Farmacêuticas , Aminoácidos , Deutério , Hidrogênio , Marcação por Isótopo , Peptídeos
6.
Geburtshilfe Frauenheilkd ; 80(6): 619-627, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32565552

RESUMO

Background Multigene assays are being used increasingly to aid in decision-making about chemotherapy in breast cancer. Here, we present the 21-gene recurrence score (RS) of patients tested in routine clinical practice in Germany. Patients and Methods In a retrospective analysis, 4695 patients with hormone receptor-positive and HER2-negative early breast cancer (pT1 - 3, pN0 - 1, M0) were included in whom RS testing was conducted in Germany between November 2015 and July 2018. RS groups as defined in the TAILORx trial (RS result 0 - 10; 11 - 25; 26 - 100) were used. Results Of these patients, 21% were assigned to the low RS group, 63% to the midrange RS group, and 15% to the high RS group. 1772 (81%) of 2175 node-negative patients over 50 years of age were grouped either into the low RS group or the midrange RS group. The portion of patients with a low or midrange RS was 90% among node-positive patients (1284 of 1432 patients), 79% among patients with Ki-67-high (≥ 20%) tumors (1829 of 2310 patients), 86% vs. 70% among patients with G2 and G3 tumors (3244 of 3762 patients and 368 of 522 patients), respectively, 88% among patients with a tumor size of > 5 cm (140 of 159 patients), and 82% among node-negative patients at high clinical risk (1110 of 1352). Conclusions The distribution of the 21-gene RS in German patients that were tested in routine clinical practice indicates that, according to the results of the TAILORx trial, chemotherapy may not be beneficial in most of these.

7.
J Org Chem ; 82(12): 6032-6043, 2017 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-28489377

RESUMO

Seven new halogenated peptides termed svetamycins A-G (1-7) have been isolated from laboratory cultures of a Streptomyces sp. Svetamycins A-D, F, and G are cyclic depsipeptides, whereas svetamycin E is a linear analogue of svetamycin C. Their structures were determined using extensive spectroscopic analysis, and their stereochemical configuration was established by a combination of NMR data, quantum mechanical calculations, and chemical derivatizations. Svetamycins are characterized by the presence of a hydroxyl acetic acid and five amino acids including a rare 4,5-dihydroxy-2,3,4,5-tetrahydropyridazine-3-carboxylic acid, a γ-halogenated piperazic acid, and a novel δ-methylated piperazic acid in svetamycins B-C, E, and G. Moreover, isotope-labeled substrate feeding experiments demonstrated ornithine as the precursor of piperazic acid and that methylation at the δ position of the piperazyl scaffold is S-adenosyl-l-methionine (SAM)-dependent. Svetamycin G, the most potent antimicrobial of this suite of compounds, inhibited the growth of Mycobacterium smegmatis with an MIC80 value of 2 µg/mL.


Assuntos
Peptídeos/química , Piridazinas/química , Streptomyces/química , Conformação Molecular , Peptídeos/isolamento & purificação , Piridazinas/isolamento & purificação , Estereoisomerismo
8.
Tuberculosis (Edinb) ; 100: 95-101, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27553416

RESUMO

The lack of proper treatment for serious infectious diseases due to the emergence of multidrug resistance reinforces the need for the discovery of novel antibiotics. This is particularly true for tuberculosis (TB) for which 3.7% of new cases and 20% of previously treated cases are estimated to be caused by multi-drug resistant strains. In addition, in the case of TB, which claimed 1.5 million lives in 2014, the treatment of the least complicated, drug sensitive cases is lengthy and disagreeable. Therefore, new drugs with novel targets are urgently needed to control resistant Mycobacterium tuberculosis strains. In this manuscript we report the characterization of the thiopeptide micrococcin P1 as an anti-tubercular agent. Our biochemical experiments show that this antibiotic inhibits the elongation step of protein synthesis in mycobacteria. We have further identified micrococcin resistant mutations in the ribosomal protein L11 (RplK); the mutations were located in the proline loop at the N-terminus. Reintroduction of the mutations into a clean genetic background, confirmed that they conferred resistance, while introduction of the wild type RplK allele into resistant strains re-established sensitivity. We also identified a mutation in the 23S rRNA gene. These data, in good agreement with previous structural studies suggest that also in M. tuberculosis micrococcin P1 functions by binding to the cleft between the 23S rRNA and the L11 protein loop, thus interfering with the binding of elongation factors Tu and G (EF-Tu and EF-G) and inhibiting protein translocation.


Assuntos
Antibióticos Antituberculose/farmacologia , Bacteriocinas/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Peptídeos/farmacologia , Animais , Antibióticos Antituberculose/administração & dosagem , Proteínas de Bactérias/biossíntese , Bacteriocinas/administração & dosagem , Células Cultivadas , Contagem de Colônia Microbiana , Relação Dose-Resposta a Droga , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos/métodos , Farmacorresistência Bacteriana/genética , Humanos , Macrófagos/microbiologia , Testes de Sensibilidade Microbiana/métodos , Mutação , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/isolamento & purificação , Elongação Traducional da Cadeia Peptídica/efeitos dos fármacos , Peptídeos/administração & dosagem , Proteínas Ribossômicas/genética
9.
Angew Chem Int Ed Engl ; 54(35): 10145-8, 2015 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-26031409

RESUMO

Microbial natural products are a rich source of bioactive molecules to serve as drug leads and/or biological tools. We investigated a little-explored myxobacterial genus, Nannocystis sp., and discovered a novel 21-membered macrocyclic scaffold that is composed of a tripeptide and a polyketide part with an epoxyamide moiety. The relative and absolute configurations of the nine stereocenters was determined by NMR spectroscopy, molecular dynamics calculations, chemical degradation, and X-ray crystallography. The compound, named nannocystin A (1), was found to inhibit cell proliferation at low nanomolar concentrations through the early induction of apoptosis. The mode of action of 1 could not be matched to that of standard drugs by transcriptional profiling and biochemical experiments. An initial investigation of the structure-activity relationship based on seven analogues demonstrated the importance of the epoxide moiety for high activity.


Assuntos
Antifúngicos/química , Antineoplásicos/química , Produtos Biológicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Compostos Macrocíclicos/farmacologia , Myxococcales/fisiologia , Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Produtos Biológicos/química , Candida albicans/efeitos dos fármacos , Cristalografia por Raios X , Descoberta de Drogas , Humanos , Compostos Macrocíclicos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
10.
Science ; 348(6239): 1106-12, 2015 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-26045430

RESUMO

The discovery of Streptomyces-produced streptomycin founded the age of tuberculosis therapy. Despite the subsequent development of a curative regimen for this disease, tuberculosis remains a worldwide problem, and the emergence of multidrug-resistant Mycobacterium tuberculosis has prioritized the need for new drugs. Here we show that new optimized derivatives from Streptomyces-derived griselimycin are highly active against M. tuberculosis, both in vitro and in vivo, by inhibiting the DNA polymerase sliding clamp DnaN. We discovered that resistance to griselimycins, occurring at very low frequency, is associated with amplification of a chromosomal segment containing dnaN, as well as the ori site. Our results demonstrate that griselimycins have high translational potential for tuberculosis treatment, validate DnaN as an antimicrobial target, and capture the process of antibiotic pressure-induced gene amplification.


Assuntos
Antituberculosos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Terapia de Alvo Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Peptídeos Cíclicos/farmacologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Animais , Antituberculosos/química , Antituberculosos/uso terapêutico , Linhagem Celular Tumoral , Cristalografia por Raios X , DNA Polimerase Dirigida por DNA , Modelos Animais de Doenças , Desenho de Fármacos , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Mycobacterium smegmatis/efeitos dos fármacos , Mycobacterium smegmatis/enzimologia , Mycobacterium tuberculosis/enzimologia , Peptídeos Cíclicos/química , Peptídeos Cíclicos/uso terapêutico , Estrutura Secundária de Proteína , Streptomyces/química , Streptomyces/efeitos dos fármacos , Streptomyces/metabolismo , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
11.
J Am Chem Soc ; 137(24): 7692-705, 2015 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-26043159

RESUMO

Telomycin (TEM) is a cyclic depsipeptide antibiotic active against Gram-positive bacteria. In this study, five new natural telomycin analogues produced by Streptomyces canus ATCC 12646 were identified. To understand the biosynthetic machinery of telomycin and to generate more analogues by pathway engineering, the TEM biosynthesis gene cluster has been characterized from S. canus ATCC 12646: it spans approximately 80.5 kb and consists of 34 genes encoding fatty acid ligase, nonribosomal peptide synthetases (NRPSs), regulators, transporters, and tailoring enzymes. The gene cluster was heterologously expressed in Streptomyces albus J1074 setting the stage for convenient biosynthetic engineering, mutasynthesis, and production optimization. Moreover, in-frame deletions of one hydroxylase and two P450 monooxygenase genes resulted in the production of novel telomycin derivatives, revealing these genes to be responsible for the specific modification by hydroxylation of three amino acids found in the TEM backbone. Surprisingly, natural lipopeptide telomycin precursors were identified when characterizing an unusual precursor deacylation mechanism during telomycin maturation. By in vivo gene inactivation and in vitro biochemical characterization of the recombinant enzyme Tem25, the maturation process was shown to involve the cleavage of previously unknown telomycin precursor-lipopeptides, to yield 6-methylheptanoic acid and telomycins. These lipopeptides were isolated from an inactivation mutant of tem25 encoding a (de)acylase, structurally elucidated, and then shown to be deacylated by recombinant Tem25. The TEM precursor and several semisynthetic lipopeptide TEM derivatives showed rapid bactericidal killing and were active against several multidrug-resistant (MDR) Gram-positive pathogens, opening the path to future chemical optimization of telomycin for pharmaceutical application.


Assuntos
Antibacterianos/metabolismo , Lipopeptídeos/metabolismo , Família Multigênica , Peptídeos/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Amidoidrolases/genética , Amidoidrolases/metabolismo , Antibacterianos/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Vias Biossintéticas , Hidroxilação , Lipopeptídeos/química , Lipopeptídeos/genética , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Peptídeo Sintases/genética , Peptídeo Sintases/metabolismo , Peptídeos/química , Peptídeos/genética , Streptomyces/química
12.
Bioorg Med Chem Lett ; 22(19): 6292-6, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22921279

RESUMO

Armeniaspiroles, a novel class of natural products isolated from Streptomyces armeniacus, are characterized by a novel spiro[4.4]non-8-ene scaffold. Various derivatives of Armeniaspiroles could be obtained by halogenation, alkylation, addition/elimination or reductions. A total synthesis of the 5-chloro analog of Armeniaspirole A has been accomplished in a linear six-step sequence. 5-Chloro-Armeniaspirole A exhibits good activity against a range of multidrug-resistant, Gram-positive bacterial pathogens.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Lactamas/farmacologia , Compostos de Espiro/farmacologia , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Produtos Biológicos/síntese química , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Relação Dose-Resposta a Droga , Canal de Potássio ERG1 , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/crescimento & desenvolvimento , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Humanos , Lactamas/química , Lactamas/isolamento & purificação , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Camundongos , Estrutura Molecular , Compostos de Espiro/química , Compostos de Espiro/isolamento & purificação , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/crescimento & desenvolvimento , Relação Estrutura-Atividade
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