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1.
Purinergic Signal ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879664

RESUMO

The human equilibrative nucleoside transporter 1 (SLC29A1, hENT1) is a solute carrier that modulates the passive transport of nucleosides and nucleobases, such as adenosine. This nucleoside regulates various physiological processes, such as vasodilation and -constriction, neurotransmission and immune defense. Marketed drugs such as dilazep and dipyridamole have proven useful in cardiovascular afflictions, but the application of hENT1 inhibitors can be beneficial in a number of other diseases. In this study, 39 derivatives of dilazep's close analogue ST7092 were designed, synthesized and subsequently assessed using [3H]NBTI displacement assays and molecular docking. Different substitution patterns of the trimethoxy benzoates of ST7092 reduced interactions within the binding pocket, resulting in diminished hENT1 affinity. Conversely, [3H]NBTI displacement by potentially covalent compounds 14b, 14c, and 14d resulted in high affinities (Ki values between 1.1 and 17.5 nM) for the transporter, primarily by the ability of accommodating the inhibitors in various ways in the binding pocket. However, any indication of covalent binding with amino acid residue C439 remained absent, conceivably as a result of decreased nucleophilic residue reactivity. In conclusion, this research introduces novel dilazep derivatives that are active as hENT1 inhibitors, along with the first high affinity dilazep derivatives equipped with an electrophilic warhead. These findings will aid the rational and structure-based development of novel hENT1 inhibitors and pharmacological tools to study hENT1's function, binding mechanisms, and its relevance in (patho)physiological conditions.

2.
ACS Chem Biol ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38920052

RESUMO

Small molecular tool compounds play an essential role in the study of G protein-coupled receptors (GPCRs). However, tool compounds most often occupy the orthosteric binding site, hampering the study of GPCRs upon ligand binding. To overcome this problem, ligand-directed labeling techniques have been developed that leave a reporter group covalently bound to the GPCR, while allowing subsequent orthosteric ligands to bind. In this work, we applied such a labeling strategy to the adenosine A2B receptor (A2BAR). We have synthetically implemented the recently reported N-acyl-N-alkyl sulfonamide (NASA) warhead into a previously developed ligand and show that the binding of the A2BAR is not restricted by NASA incorporation. Furthermore, we have investigated ligand-directed labeling of the A2BAR using SDS-PAGE, flow cytometric, and mass spectrometry techniques. We have found one of the synthesized probes to specifically label the A2BAR, although detection was hindered by nonspecific protein labeling most likely due to the intrinsic reactivity of the NASA warhead. Altogether, this work aids the future development of ligand-directed probes for the detection of GPCRs.

3.
Int J Mol Sci ; 25(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38612509

RESUMO

Cancer remains a leading cause of mortality worldwide and calls for novel therapeutic targets. Membrane proteins are key players in various cancer types but present unique challenges compared to soluble proteins. The advent of computational drug discovery tools offers a promising approach to address these challenges, allowing for the prioritization of "wet-lab" experiments. In this review, we explore the applications of computational approaches in membrane protein oncological characterization, particularly focusing on three prominent membrane protein families: receptor tyrosine kinases (RTKs), G protein-coupled receptors (GPCRs), and solute carrier proteins (SLCs). We chose these families due to their varying levels of understanding and research data availability, which leads to distinct challenges and opportunities for computational analysis. We discuss the utilization of multi-omics data, machine learning, and structure-based methods to investigate aberrant protein functionalities associated with cancer progression within each family. Moreover, we highlight the importance of considering the broader cellular context and, in particular, cross-talk between proteins. Despite existing challenges, computational tools hold promise in dissecting membrane protein dysregulation in cancer. With advancing computational capabilities and data resources, these tools are poised to play a pivotal role in identifying and prioritizing membrane proteins as personalized anticancer targets.


Assuntos
Proteínas de Membrana , Neoplasias , Humanos , Reações Cruzadas , Descoberta de Drogas , Aprendizado de Máquina , Neoplasias/tratamento farmacológico
4.
J Clin Oncol ; 42(15): 1799-1809, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38640453

RESUMO

PURPOSE: To compare outcomes after laparoscopic versus open major liver resection (hemihepatectomy) mainly for primary or metastatic cancer. The primary outcome measure was time to functional recovery. Secondary outcomes included morbidity, quality of life (QoL), and for those with cancer, resection margin status and time to adjuvant systemic therapy. PATIENTS AND METHODS: This was a multicenter, randomized controlled, patient-blinded, superiority trial on adult patients undergoing hemihepatectomy. Patients were recruited from 16 hospitals in Europe between November 2013 and December 2018. RESULTS: Of the 352 randomly assigned patients, 332 patients (94.3%) underwent surgery (laparoscopic, n = 166 and open, n = 166) and comprised the analysis population. The median time to functional recovery was 4 days (IQR, 3-5; range, 1-30) for laparoscopic hemihepatectomy versus 5 days (IQR, 4-6; range, 1-33) for open hemihepatectomy (difference, -17.5% [96% CI, -25.6 to -8.4]; P < .001). There was no difference in major complications (laparoscopic 24/166 [14.5%] v open 28/166 [16.9%]; odds ratio [OR], 0.84; P = .58). Regarding QoL, both global health status (difference, 3.2 points; P < .001) and body image (difference, 0.9 points; P < .001) scored significantly higher in the laparoscopic group. For the 281 (84.6%) patients with cancer, R0 resection margin status was similar (laparoscopic 106 [77.9%] v open 122 patients [84.1%], OR, 0.60; P = .14) with a shorter time to adjuvant systemic therapy in the laparoscopic group (46.5 days v 62.8 days, hazard ratio, 2.20; P = .009). CONCLUSION: Among patients undergoing hemihepatectomy, the laparoscopic approach resulted in a shorter time to functional recovery compared with open surgery. In addition, it was associated with a better QoL, and in patients with cancer, a shorter time to adjuvant systemic therapy with no adverse impact on cancer outcomes observed.


Assuntos
Hepatectomia , Laparoscopia , Neoplasias Hepáticas , Qualidade de Vida , Humanos , Hepatectomia/métodos , Hepatectomia/efeitos adversos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/secundário , Idoso , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Adulto , Resultado do Tratamento
6.
Front Mol Biosci ; 10: 1286673, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074092

RESUMO

Glutamate is an essential excitatory neurotransmitter and an intermediate for energy metabolism. Depending on the tumor site, cancer cells have increased or decreased expression of excitatory amino acid transporter 1 or 2 (EAAT1/2, SLC1A3/2) to regulate glutamate uptake for the benefit of tumor growth. Thus, EAAT1/2 may be an attractive target for therapeutic intervention in oncology. Genetic variation of EAAT1 has been associated with rare cases of episodic ataxia, but the occurrence and functional contribution of EAAT1 mutants in other diseases, such as cancer, is poorly understood. Here, 105 unique somatic EAAT1 mutations were identified in cancer patients from the Genomic Data Commons dataset. Using EAAT1 crystal structures and in silico studies, eight mutations were selected based on their close proximity to the orthosteric or allosteric ligand binding sites and the predicted change in ligand binding affinity. In vitro functional assessment in a live-cell, impedance-based phenotypic assay demonstrated that these mutants differentially affect L-glutamate and L-aspartate transport, as well as the inhibitory potency of an orthosteric (TFB-TBOA) and allosteric (UCPH-101) inhibitor. Moreover, two episodic ataxia-related mutants displayed functional responses that were in line with literature, which confirmed the validity of our assay. Of note, ataxia-related mutant M128R displayed inhibitor-induced functional responses never described before. Finally, molecular dynamics (MD) simulations were performed to gain mechanistic insights into the observed functional effects. Taken together, the results in this work demonstrate 1) the suitability of the label-free phenotypic method to assess functional variation of EAAT1 mutants and 2) the opportunity and challenges of using in silico techniques to rationalize the in vitro phenotype of disease-relevant mutants.

7.
J Chem Inf Model ; 63(17): 5433-5445, 2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37616385

RESUMO

Oxidative stress is the consequence of an abnormal increase of reactive oxygen species (ROS). ROS are generated mainly during the metabolism in both normal and pathological conditions as well as from exposure to xenobiotics. Xenobiotics can, on the one hand, disrupt molecular machinery involved in redox processes and, on the other hand, reduce the effectiveness of the antioxidant activity. Such dysregulation may lead to oxidative damage when combined with oxidative stress overpassing the cell capacity to detoxify ROS. In this work, a green fluorescent protein (GFP)-tagged nuclear factor erythroid 2-related factor 2 (NRF2)-regulated sulfiredoxin reporter (Srxn1-GFP) was used to measure the antioxidant response of HepG2 cells to a large series of drug and drug-like compounds (2230 compounds). These compounds were then classified as positive or negative depending on cellular response and distributed among different modeling groups to establish structure-activity relationship (SAR) models. A selection of models was used to prospectively predict oxidative stress induced by a new set of compounds subsequently experimentally tested to validate the model predictions. Altogether, this exercise exemplifies the different challenges of developing SAR models of a phenotypic cellular readout, model combination, chemical space selection, and results interpretation.


Assuntos
Estresse Oxidativo , Xenobióticos , Humanos , Espécies Reativas de Oxigênio , Células Hep G2 , Estudos Prospectivos , Relação Estrutura-Atividade
8.
Artigo em Inglês | MEDLINE | ID: mdl-37642704

RESUMO

PURPOSE: Fluorescence-guided surgery (FGS) can play a key role in improving radical resection rates by assisting surgeons to gain adequate visualization of malignant tissue intraoperatively. Designed ankyrin repeat proteins (DARPins) possess optimal pharmacokinetic and other properties for in vivo imaging. This study aims to evaluate the preclinical potential of epithelial cell adhesion molecule (EpCAM)-binding DARPins as targeting moieties for near-infrared fluorescence (NIRF) and photoacoustic (PA) imaging of cancer. METHODS: EpCAM-binding DARPins Ac2, Ec4.1, and non-binding control DARPin Off7 were conjugated to IRDye 800CW and their binding efficacy was evaluated on EpCAM-positive HT-29 and EpCAM-negative COLO-320 human colon cancer cell lines. Thereafter, NIRF and PA imaging of all three conjugates were performed in HT-29_luc2 tumor-bearing mice. At 24 h post-injection, tumors and organs were resected and tracer biodistributions were analyzed. RESULTS: Ac2-800CW and Ec4.1-800CW specifically bound to HT-29 cells, but not to COLO-320 cells. Next, 6 nmol and 24 h were established as the optimal in vivo dose and imaging time point for both DARPin tracers. At 24 h post-injection, mean tumor-to-background ratios of 2.60 ± 0.3 and 3.1 ± 0.3 were observed for Ac2-800CW and Ec4.1-800CW, respectively, allowing clear tumor delineation using the clinical Artemis NIRF imager. Biodistribution analyses in non-neoplastic tissue solely showed high fluorescence signal in the liver and kidney, which reflects the clearance of the DARPin tracers. CONCLUSION: Our encouraging results show that EpCAM-binding DARPins are a promising class of targeting moieties for pan-carcinoma targeting, providing clear tumor delineation at 24 h post-injection. The work described provides the preclinical foundation for DARPin-based bimodal NIRF/PA imaging of cancer.

9.
J Cheminform ; 15(1): 74, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37641107

RESUMO

Proteochemometric (PCM) modelling is a powerful computational drug discovery tool used in bioactivity prediction of potential drug candidates relying on both chemical and protein information. In PCM features are computed to describe small molecules and proteins, which directly impact the quality of the predictive models. State-of-the-art protein descriptors, however, are calculated from the protein sequence and neglect the dynamic nature of proteins. This dynamic nature can be computationally simulated with molecular dynamics (MD). Here, novel 3D dynamic protein descriptors (3DDPDs) were designed to be applied in bioactivity prediction tasks with PCM models. As a test case, publicly available G protein-coupled receptor (GPCR) MD data from GPCRmd was used. GPCRs are membrane-bound proteins, which are activated by hormones and neurotransmitters, and constitute an important target family for drug discovery. GPCRs exist in different conformational states that allow the transmission of diverse signals and that can be modified by ligand interactions, among other factors. To translate the MD-encoded protein dynamics two types of 3DDPDs were considered: one-hot encoded residue-specific (rs) and embedding-like protein-specific (ps) 3DDPDs. The descriptors were developed by calculating distributions of trajectory coordinates and partial charges, applying dimensionality reduction, and subsequently condensing them into vectors per residue or protein, respectively. 3DDPDs were benchmarked on several PCM tasks against state-of-the-art non-dynamic protein descriptors. Our rs- and ps3DDPDs outperformed non-dynamic descriptors in regression tasks using a temporal split and showed comparable performance with a random split and in all classification tasks. Combinations of non-dynamic descriptors with 3DDPDs did not result in increased performance. Finally, the power of 3DDPDs to capture dynamic fluctuations in mutant GPCRs was explored. The results presented here show the potential of including protein dynamic information on machine learning tasks, specifically bioactivity prediction, and open opportunities for applications in drug discovery, including oncology.

10.
J Med Chem ; 66(16): 11399-11413, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37531576

RESUMO

The adenosine A3 receptor (A3AR) is a G protein-coupled receptor (GPCR) that exerts immunomodulatory effects in pathophysiological conditions such as inflammation and cancer. Thus far, studies toward the downstream effects of A3AR activation have yielded contradictory results, thereby motivating the need for further investigations. Various chemical and biological tools have been developed for this purpose, ranging from fluorescent ligands to antibodies. Nevertheless, these probes are limited by their reversible mode of binding, relatively large size, and often low specificity. Therefore, in this work, we have developed a clickable and covalent affinity-based probe (AfBP) to target the human A3AR. Herein, we show validation of the synthesized AfBP in radioligand displacement, SDS-PAGE, and confocal microscopy experiments as well as utilization of the AfBP for the detection of endogenous A3AR expression in flow cytometry experiments. Ultimately, this AfBP will aid future studies toward the expression and function of the A3AR in pathologies.


Assuntos
Adenosina , Receptor A3 de Adenosina , Humanos , Adenosina/farmacologia , Receptor A3 de Adenosina/metabolismo , Expressão Gênica , Receptores Acoplados a Proteínas G , Agonistas do Receptor A3 de Adenosina/farmacologia
11.
J Chem Inf Model ; 63(12): 3688-3696, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37294674

RESUMO

Protein kinases are a protein family that plays an important role in several complex diseases such as cancer and cardiovascular and immunological diseases. Protein kinases have conserved ATP binding sites, which when targeted can lead to similar activities of inhibitors against different kinases. This can be exploited to create multitarget drugs. On the other hand, selectivity (lack of similar activities) is desirable in order to avoid toxicity issues. There is a vast amount of protein kinase activity data in the public domain, which can be used in many different ways. Multitask machine learning models are expected to excel for these kinds of data sets because they can learn from implicit correlations between tasks (in this case activities against a variety of kinases). However, multitask modeling of sparse data poses two major challenges: (i) creating a balanced train-test split without data leakage and (ii) handling missing data. In this work, we construct a protein kinase benchmark set composed of two balanced splits without data leakage, using random and dissimilarity-driven cluster-based mechanisms, respectively. This data set can be used for benchmarking and developing protein kinase activity prediction models. Overall, the performance on the dissimilarity-driven cluster-based split is lower than on random split-based sets for all models, indicating poor generalizability of models. Nevertheless, we show that multitask deep learning models, on this very sparse data set, outperform single-task deep learning and tree-based models. Finally, we demonstrate that data imputation does not improve the performance of (multitask) models on this benchmark set.


Assuntos
Aprendizado de Máquina , Proteínas , Proteínas Quinases , Fosforilação , Processamento de Proteína Pós-Traducional
12.
J Cheminform ; 15(1): 24, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36803659

RESUMO

Rational drug design often starts from specific scaffolds to which side chains/substituents are added or modified due to the large drug-like chemical space available to search for novel drug-like molecules. With the rapid growth of deep learning in drug discovery, a variety of effective approaches have been developed for de novo drug design. In previous work we proposed a method named DrugEx, which can be applied in polypharmacology based on multi-objective deep reinforcement learning. However, the previous version is trained under fixed objectives and does not allow users to input any prior information (i.e. a desired scaffold). In order to improve the general applicability, we updated DrugEx to design drug molecules based on scaffolds which consist of multiple fragments provided by users. Here, a  Transformer model was employed to generate molecular structures. The Transformer is a multi-head self-attention deep learning model containing an encoder to receive scaffolds as input and a decoder to generate molecules as output. In order to deal with the graph representation of molecules a novel positional encoding for each atom and bond based on an adjacency matrix was proposed, extending the architecture of the Transformer. The graph Transformer model contains growing and connecting procedures for molecule generation starting from  a given scaffold based on fragments. Moreover, the generator was trained under a reinforcement learning framework to increase the number of desired ligands. As a proof of concept, the method was applied to design ligands for the adenosine A2A receptor (A2AAR) and compared with SMILES-based methods. The results show that 100% of the generated molecules are valid and most of them had a high predicted affinity value towards A2AAR with given scaffolds.

13.
Molecules ; 27(15)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35897852

RESUMO

The adenosine A2A receptor (A2AAR) is a class A G-protein-coupled receptor (GPCR). It is an immune checkpoint in the tumor micro-environment and has become an emerging target for cancer treatment. In this study, we aimed to explore the effects of cancer-patient-derived A2AAR mutations on ligand binding and receptor functions. The wild-type A2AAR and 15 mutants identified by Genomic Data Commons (GDC) in human cancers were expressed in HEK293T cells. Firstly, we found that the binding affinity for agonist NECA was decreased in six mutants but increased for the V275A mutant. Mutations A165V and A265V decreased the binding affinity for antagonist ZM241385. Secondly, we found that the potency of NECA (EC50) in an impedance-based cell-morphology assay was mostly correlated with the binding affinity for the different mutants. Moreover, S132L and H278N were found to shift the A2AAR towards the inactive state. Importantly, we found that ZM241385 could not inhibit the activation of V275A and P285L stimulated by NECA. Taken together, the cancer-associated mutations of A2AAR modulated ligand binding and receptor functions. This study provides fundamental insights into the structure-activity relationship of the A2AAR and provides insights for A2AAR-related personalized treatment in cancer.


Assuntos
Adenosina , Neoplasias , Adenosina/farmacologia , Adenosina-5'-(N-etilcarboxamida) , Células HEK293 , Humanos , Ligantes , Mutação , Neoplasias/tratamento farmacológico , Neoplasias/genética , Receptor A2A de Adenosina/genética , Receptor A2A de Adenosina/metabolismo , Microambiente Tumoral
14.
Cancer Radiother ; 26(8): 1075-1077, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35843781

RESUMO

The purpose of this article is to remind the importance of the inverse square law in radiotherapy and especially in brachytherapy. Indeed, beyond the impact in radiation therapy with high energy beam, there is the use of radionuclides and low energy photons with short FSD where it is still more important. Comparisons between Iridium Brachytherapy and low energy X-rays brachytherapy show equivalent dose distributions in the first few centimeters. If the inverse square law is not the only element influencing the dose distributions calculations, it must not be forgotten. And it is playing a major role in brachytherapy with short FSD (<6cm).


Assuntos
Braquiterapia , Radioterapia (Especialidade) , Humanos , Fótons/uso terapêutico , Radioisótopos/uso terapêutico , Raios X , Dosagem Radioterapêutica , Radioisótopos de Irídio/uso terapêutico
15.
Molecules ; 27(12)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35744872

RESUMO

Overexpression of the adenosine A1 receptor (A1AR) has been detected in various cancer cell lines. However, the role of A1AR in tumor development is still unclear. Thirteen A1AR mutations were identified in the Cancer Genome Atlas from cancer patient samples. We have investigated the pharmacology of the mutations located at the 7-transmembrane domain using a yeast system. Concentration-growth curves were obtained with the full agonist CPA and compared to the wild type hA1AR. H78L3.23 and S246T6.47 showed increased constitutive activity, while only the constitutive activity of S246T6.47 could be reduced to wild type levels by the inverse agonist DPCPX. Decreased constitutive activity was observed on five mutant receptors, among which A52V2.47 and W188C5.46 showed a diminished potency for CPA. Lastly, a complete loss of activation was observed in five mutant receptors. A selection of mutations was also investigated in a mammalian system, showing comparable effects on receptor activation as in the yeast system, except for residues pointing toward the membrane. Taken together, this study will enrich the view of the receptor structure and function of A1AR, enlightening the consequences of these mutations in cancer. Ultimately, this may provide an opportunity for precision medicine for cancer patients with pathological phenotypes involving these mutations.


Assuntos
Neoplasias , Receptor A1 de Adenosina , Adenosina/metabolismo , Adenosina/farmacologia , Animais , Humanos , Mamíferos , Mutação , Neoplasias/tratamento farmacológico , Neoplasias/genética , Estrutura Secundária de Proteína , Receptor A1 de Adenosina/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
16.
FASEB J ; 36(6): e22358, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35604751

RESUMO

G protein-coupled receptors (GPCRs) are known to be involved in tumor progression and metastasis. The adenosine A1 receptor (A1 AR) has been detected to be over-expressed in various cancer cell lines. However, the role of A1 AR in tumor development is not yet well characterized. A series of A1 AR mutations were identified in the Cancer Genome Atlas from cancer patient samples. In this study, we have investigated the pharmacology of mutations located outside of the 7-transmembrane domain by using a "single-GPCR-one-G protein" yeast system. Concentration-growth curves were obtained with the full agonist CPA for 12 mutant receptors and compared to the wild-type hA1 AR. Most mutations located at the extracellular loops (EL) reduced the levels of constitutive activity of the receptor and agonist potency. For mutants at the intracellular loops (ILs) of the receptor, an increased constitutive activity was found for mutant receptor L211R5.69 , while a decreased constitutive activity and agonist response were found for mutant receptor L113F34.51 . Lastly, mutations identified on the C-terminus did not significantly influence the pharmacological function of the receptor. A selection of mutations was also investigated in a mammalian system. Overall, similar effects on receptor activation compared to the yeast system were found with mutations located at the EL, but some contradictory effects were observed for mutations located at the IL. Taken together, this study will enrich the insight of A1 AR structure and function, enlightening the consequences of these mutations in cancer. Ultimately, this may provide potential precision medicine in cancer treatment.


Assuntos
Neoplasias , Adenosina/farmacologia , Animais , Linhagem Celular , Humanos , Mamíferos/metabolismo , Mutação , Neoplasias/tratamento farmacológico , Neoplasias/genética , Receptor A1 de Adenosina/genética , Receptor A1 de Adenosina/metabolismo , Saccharomyces cerevisiae/genética
17.
J Chem Inf Model ; 62(24): 6323-6335, 2022 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-35274943

RESUMO

Integration of statistical learning methods with structure-based modeling approaches is a contemporary strategy to identify novel lead compounds in drug discovery. Hepatic organic anion transporting polypeptides (OATP1B1, OATP1B3, and OATP2B1) are classical off-targets, and it is well recognized that their ability to interfere with a wide range of chemically unrelated drugs, environmental chemicals, or food additives can lead to unwanted adverse effects like liver toxicity and drug-drug or drug-food interactions. Therefore, the identification of novel (tool) compounds for hepatic OATPs by virtual screening approaches and subsequent experimental validation is a major asset for elucidating structure-function relationships of (related) transporters: they enhance our understanding about molecular determinants and structural aspects of hepatic OATPs driving ligand binding and selectivity. In the present study, we performed a consensus virtual screening approach by using different types of machine learning models (proteochemometric models, conformal prediction models, and XGBoost models for hepatic OATPs), followed by molecular docking of preselected hits using previously established structural models for hepatic OATPs. Screening the diverse REAL drug-like set (Enamine) shows a comparable hit rate for OATP1B1 (36% actives) and OATP1B3 (32% actives), while the hit rate for OATP2B1 was even higher (66% actives). Percentage inhibition values for 44 selected compounds were determined using dedicated in vitro assays and guided the prioritization of several highly potent novel hepatic OATP inhibitors: six (strong) OATP2B1 inhibitors (IC50 values ranging from 0.04 to 6 µM), three OATP1B1 inhibitors (2.69 to 10 µM), and five OATP1B3 inhibitors (1.53 to 10 µM) were identified. Strikingly, two novel OATP2B1 inhibitors were uncovered (C7 and H5) which show high affinity (IC50 values: 40 nM and 390 nM) comparable to the recently described estrone-based inhibitor (IC50 = 41 nM). A molecularly detailed explanation for the observed differences in ligand binding to the three transporters is given by means of structural comparison of the detected binding sites and docking poses.


Assuntos
Transportadores de Ânions Orgânicos , Transportadores de Ânions Orgânicos/metabolismo , Transportador 1 de Ânion Orgânico Específico do Fígado/metabolismo , Simulação de Acoplamento Molecular , Ligantes , Membro 1B3 da Família de Transportadores de Ânion Orgânico Carreador de Soluto/metabolismo , Transporte Biológico/fisiologia , Fígado/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Peptídeos/metabolismo , Interações Medicamentosas
18.
Trials ; 23(1): 206, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35264216

RESUMO

BACKGROUND: A shift towards parenchymal-sparing liver resections in open and laparoscopic surgery emerged in the last few years. Laparoscopic liver resection is technically feasible and safe, and consensus guidelines acknowledge the laparoscopic approach in the posterosuperior segments. Lesions situated in these segments are considered the most challenging for the laparoscopic approach. The aim of this trial is to compare the postoperative time to functional recovery, complications, oncological safety, quality of life, survival and costs after laparoscopic versus open parenchymal-sparing liver resections in the posterosuperior liver segments within an enhanced recovery setting. METHODS: The ORANGE Segments trial is an international multicentre randomised controlled superiority trial conducted in centres experienced in laparoscopic liver resection. Eligible patients for minor resections in the posterosuperior segments will be randomised in a 1:1 ratio to undergo laparoscopic or open resections in an enhanced recovery setting. Patients and ward personnel are blinded to the treatment allocation until postoperative day 4 using a large abdominal dressing. The primary endpoint is time to functional recovery. Secondary endpoints include intraoperative outcomes, length of stay, resection margin, postoperative complications, 90-day mortality, time to adjuvant chemotherapy initiation, quality of life and overall survival. Laparoscopic liver surgery of the posterosuperior segments is hypothesised to reduce time to functional recovery by 2 days in comparison with open surgery. With a power of 80% and alpha of 0.04 to adjust for interim analysis halfway the trial, a total of 250 patients are required to be randomised. DISCUSSION: The ORANGE Segments trial is the first multicentre international randomised controlled study to compare short- and long-term surgical and oncological outcomes of laparoscopic and open resections in the posterosuperior segments within an enhanced recovery programme. TRIAL REGISTRATION: ClinicalTrials.gov NCT03270917 . Registered on September 1, 2017. Before start of inclusion. PROTOCOL VERSION: version 12, May 9, 2017.


Assuntos
Hepatectomia , Laparoscopia , Neoplasias Hepáticas , Hepatectomia/efeitos adversos , Hepatectomia/métodos , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Tempo de Internação , Neoplasias Hepáticas/cirurgia , Estudos Multicêntricos como Assunto , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
19.
Drug Discov Today ; 27(6): 1661-1670, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35301149

RESUMO

The integration of machine learning and structure-based methods has proven valuable in the past as a way to prioritize targets and compounds in early drug discovery. In oncological research, these methods can be highly beneficial in addressing the diversity of neoplastic diseases portrayed by the different hallmarks of cancer. Here, we review six use case scenarios for integrated computational methods, namely driver prediction, computational mutagenesis, (off)-target prediction, binding site prediction, virtual screening, and allosteric modulation analysis. We address the heterogeneity of integration approaches and individual methods, while acknowledging their current limitations and highlighting their potential to bring drugs for personalized oncological therapies to the market faster.


Assuntos
Inteligência Artificial , Descoberta de Drogas , Descoberta de Drogas/métodos , Aprendizado de Máquina
20.
Cancer Radiother ; 26(1-2): 272-278, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34953708

RESUMO

We present the updated recommendations of the French society of oncological radiotherapy for rectal cancer radiotherapy. The standard treatment for locally advanced rectal cancer consists in chemoradiotherapy followed by radical surgery with total mesorectal resection and adjuvant chemotherapy according to nodal status. Although this strategy efficiently reduced local recurrences rates below 5% in expert centres, functional sequelae could not be avoided resulting in 20 to 30% morbidity rates. The early introduction of neoadjuvant chemotherapy has proven beneficial in recent trials, in terms of recurrence free and metastasis free survivals. Complete pathological responses were obtained in 15% of tumours treated by chemoradiation, even reaching up to 30% of tumours when neoadjuvant chemotherapy is associated to chemoradiotherapy. These good results question the relevance of systematic radical surgery in good responders. Personalized therapeutic strategies are now possible by improved imaging modalities with circumferential margin assessed by magnetic resonance imaging, by intensity modulated radiotherapy and by refining surgical techniques, and contribute to morbidity reduction. Keeping the same objectives, ongoing trials are now evaluating therapeutic de-escalation strategies, in particular rectal preservation for good responders after neoadjuvant treatment, or radiotherapy omission in selected cases (Greccar 12, Opera, Norad).


Assuntos
Radioterapia de Intensidade Modulada/métodos , Neoplasias Retais/radioterapia , Quimiorradioterapia , Quimioterapia Adjuvante , França , Humanos , Terapia Neoadjuvante , Recidiva Local de Neoplasia/prevenção & controle , Tratamentos com Preservação do Órgão/métodos , Órgãos em Risco/diagnóstico por imagem , Posicionamento do Paciente , Radioterapia (Especialidade) , Dosagem Radioterapêutica , Radioterapia Guiada por Imagem , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Reto/cirurgia , Carga Tumoral
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