RESUMO
Receptor-interacting serine/threonine-protein kinase 1 (RIPK1) functions as a critical stress sentinel that coordinates cell survival, inflammation, and immunogenic cell death (ICD). Although the catalytic function of RIPK1 is required to trigger cell death, its non-catalytic scaffold function mediates strong pro-survival signaling. Accordingly, cancer cells can hijack RIPK1 to block necroptosis and evade immune detection. We generated a small-molecule proteolysis-targeting chimera (PROTAC) that selectively degraded human and murine RIPK1. PROTAC-mediated depletion of RIPK1 deregulated TNFR1 and TLR3/4 signaling hubs, accentuating the output of NF-κB, MAPK, and IFN signaling. Additionally, RIPK1 degradation simultaneously promoted RIPK3 activation and necroptosis induction. We further demonstrated that RIPK1 degradation enhanced the immunostimulatory effects of radio- and immunotherapy by sensitizing cancer cells to treatment-induced TNF and interferons. This promoted ICD, antitumor immunity, and durable treatment responses. Consequently, targeting RIPK1 by PROTACs emerges as a promising approach to overcome radio- or immunotherapy resistance and enhance anticancer therapies.
Assuntos
Morte Celular Imunogênica , Proteólise , Proteína Serina-Treonina Quinases de Interação com Receptores , Transdução de Sinais , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Humanos , Animais , Camundongos , Proteólise/efeitos dos fármacos , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Morte Celular Imunogênica/efeitos dos fármacos , Necroptose/efeitos dos fármacos , Necroptose/imunologia , Neoplasias/imunologia , Neoplasias/tratamento farmacológico , Camundongos Endogâmicos C57BL , Antineoplásicos/farmacologia , Imunoterapia/métodosRESUMO
[This corrects the article DOI: 10.1016/j.isci.2023.107059.].
RESUMO
Hedgehog signaling is involved in embryonic development and cancer growth. Functional activity of secreted Hedgehog signaling proteins is dependent on N-terminal palmitoylation, making the palmitoyl transferase Hedgehog acyltransferase (HHAT), a potential drug target and a series of 4,5,6,7-tetrahydrothieno[3,2-c]pyridines have been identified as HHAT inhibitors. Based on structural data, we designed and synthesized 37 new analogues which we profiled alongside 13 previously reported analogues in enzymatic and cellular assays. Our results show that a central amide linkage, a secondary amine, and (R)-configuration at the 4-position of the core are three key factors for inhibitory potency. Several potent analogues with low- or sub-µM IC50 against purified HHAT also inhibit Sonic Hedgehog (SHH) palmitoylation in cells and suppress the SHH signaling pathway. This work identifies IMP-1575 as the most potent cell-active chemical probe for HHAT function, alongside an inactive control enantiomer, providing tool compounds for validation of HHAT as a target in cellular assays.
Assuntos
Proteínas Hedgehog , Proteínas Hedgehog/metabolismo , Piridinas/química , Piridinas/farmacologiaRESUMO
Inflammation is a hallmark of cancer1. In patients with cancer, peripheral blood myeloid expansion, indicated by a high neutrophil-to-lymphocyte ratio, associates with shorter survival and treatment resistance across malignancies and therapeutic modalities2-5. Whether myeloid inflammation drives progression of prostate cancer in humans remain unclear. Here we show that inhibition of myeloid chemotaxis can reduce tumour-elicited myeloid inflammation and reverse therapy resistance in a subset of patients with metastatic castration-resistant prostate cancer (CRPC). We show that a higher blood neutrophil-to-lymphocyte ratio reflects tumour myeloid infiltration and tumour expression of senescence-associated mRNA species, including those that encode myeloid-chemoattracting CXCR2 ligands. To determine whether myeloid cells fuel resistance to androgen receptor signalling inhibitors, and whether inhibiting CXCR2 to block myeloid chemotaxis reverses this, we conducted an investigator-initiated, proof-of-concept clinical trial of a CXCR2 inhibitor (AZD5069) plus enzalutamide in patients with metastatic CRPC that is resistant to androgen receptor signalling inhibitors. This combination was well tolerated without dose-limiting toxicity and it decreased circulating neutrophil levels, reduced intratumour CD11b+HLA-DRloCD15+CD14- myeloid cell infiltration and imparted durable clinical benefit with biochemical and radiological responses in a subset of patients with metastatic CRPC. This study provides clinical evidence that senescence-associated myeloid inflammation can fuel metastatic CRPC progression and resistance to androgen receptor blockade. Targeting myeloid chemotaxis merits broader evaluation in other cancers.
Assuntos
Antagonistas de Receptores de Andrógenos , Antineoplásicos , Quimiotaxia , Resistencia a Medicamentos Antineoplásicos , Células Mieloides , Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Quimiotaxia/efeitos dos fármacos , Progressão da Doença , Inflamação/tratamento farmacológico , Inflamação/patologia , Antígenos CD15/metabolismo , Células Mieloides/efeitos dos fármacos , Células Mieloides/patologia , Metástase Neoplásica , Próstata/efeitos dos fármacos , Próstata/metabolismo , Próstata/patologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Receptores Androgênicos/metabolismo , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêuticoRESUMO
To address the limitation associated with degron based systems, we have developed iTAG, a synthetic tag based on IMiDs/CELMoDs mechanism of action that improves and addresses the limitations of both PROTAC and previous IMiDs/CeLMoDs based tags. Using structural and sequence analysis, we systematically explored native and chimeric degron containing domains (DCDs) and evaluated their ability to induce degradation. We identified the optimal chimeric iTAG(DCD23 60aa) that elicits robust degradation of targets across cell types and subcellular localizations without exhibiting the well documented "hook effect" of PROTAC-based systems. We showed that iTAG can also induce target degradation by murine CRBN and enabled the exploration of natural neo-substrates that can be degraded by murine CRBN. Hence, the iTAG system constitutes a versatile tool to degrade targets across the human and murine proteome.
RESUMO
CCT251236 1, a potent chemical probe, was previously developed from a cell-based phenotypic high-throughput screen (HTS) to discover inhibitors of transcription mediated by HSF1, a transcription factor that supports malignancy. Owing to its activity against models of refractory human ovarian cancer, 1 was progressed into lead optimization. The reduction of P-glycoprotein efflux became a focus of early compound optimization; central ring halogen substitution was demonstrated by matched molecular pair analysis to be an effective strategy to mitigate this liability. Further multiparameter optimization led to the design of the clinical candidate, CCT361814/NXP800 22, a potent and orally bioavailable fluorobisamide, which caused tumor regression in a human ovarian adenocarcinoma xenograft model with on-pathway biomarker modulation and a clean in vitro safety profile. Following its favorable dose prediction to human, 22 has now progressed to phase 1 clinical trial as a potential future treatment for refractory ovarian cancer and other malignancies.
Assuntos
Antineoplásicos , Neoplasias Ovarianas , Humanos , Feminino , Fatores de Transcrição/metabolismo , Neoplasias Ovarianas/patologia , Linhagem Celular Tumoral , Antineoplásicos/farmacologiaRESUMO
B-cell lymphoma 6 (BCL6) is a transcriptional repressor and oncogenic driver of diffuse large B-cell lymphoma (DLBCL). Here, we report the optimization of our previously reported tricyclic quinolinone series for the inhibition of BCL6. We sought to improve the cellular potency and in vivo exposure of the non-degrading isomer, CCT373567, of our recently published degrader, CCT373566. The major limitation of our inhibitors was their high topological polar surface areas (TPSA), leading to increased efflux ratios. Reducing the molecular weight allowed us to remove polarity and decrease TPSA without considerably reducing solubility. Careful optimization of these properties, as guided by pharmacokinetic studies, led to the discovery of CCT374705, a potent inhibitor of BCL6 with a good in vivo profile. Modest in vivo efficacy was achieved in a lymphoma xenograft mouse model after oral dosing.
Assuntos
Linfoma Difuso de Grandes Células B , Quinolonas , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Modelos Animais de Doenças , Linfoma Difuso de Grandes Células B/patologia , Proteínas Proto-Oncogênicas c-bcl-6/química , Fatores de TranscriçãoRESUMO
Circadian rhythms influence physiology, metabolism, and molecular processes in the human body. Estimation of individual body time (circadian phase) is therefore highly relevant for individual optimization of behavior (sleep, meals, sports), diagnostic sampling, medical treatment, and for treatment of circadian rhythm disorders. Here, we provide a partial least squares regression (PLSR) machine learning approach that uses plasma-derived metabolomics data in one or more samples to estimate dim light melatonin onset (DLMO) as a proxy for circadian phase of the human body. For this purpose, our protocol was aimed to stay close to real-life conditions. We found that a metabolomics approach optimized for either women or men under entrained conditions performed equally well or better than existing approaches using more labor-intensive RNA sequencing-based methods. Although estimation of circadian body time using blood-targeted metabolomics requires further validation in shift work and other real-world conditions, it currently may offer a robust, feasible technique with relatively high accuracy to aid personalized optimization of behavior and clinical treatment after appropriate validation in patient populations.
Assuntos
Corpo Humano , Melatonina , Masculino , Humanos , Feminino , Luz , Ritmo Circadiano/fisiologia , Sono/fisiologia , Melatonina/metabolismo , MetabolômicaRESUMO
By suppressing gene transcription through the recruitment of corepressor proteins, B-cell lymphoma 6 (BCL6) protein controls a transcriptional network required for the formation and maintenance of B-cell germinal centres. As BCL6 deregulation is implicated in the development of Diffuse Large B-Cell Lymphoma, we sought to discover novel small molecule inhibitors that disrupt the BCL6-corepressor protein-protein interaction (PPI). Here we report our hit finding and compound optimisation strategies, which provide insight into the multi-faceted orthogonal approaches that are needed to tackle this challenging PPI with small molecule inhibitors. Using a 1536-well plate fluorescence polarisation high throughput screen we identified multiple hit series, which were followed up by hit confirmation using a thermal shift assay, surface plasmon resonance and ligand-observed NMR. We determined X-ray structures of BCL6 bound to compounds from nine different series, enabling a structure-based drug design approach to improve their weak biochemical potency. We developed a time-resolved fluorescence energy transfer biochemical assay and a nano bioluminescence resonance energy transfer cellular assay to monitor cellular activity during compound optimisation. This workflow led to the discovery of novel inhibitors with respective biochemical and cellular potencies (IC50s) in the sub-micromolar and low micromolar range.
Assuntos
Linfoma Difuso de Grandes Células B , Humanos , Cristalografia por Raios X , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Desenho de Fármacos , LigantesRESUMO
Caco-2 screens are routinely used in laboratories to measure the permeability of compounds and can identify substrates of efflux transporters. In this study, we hypothesized that efflux transporter inhibition of a compound can be predicted by an intracellular metabolic signature in Caco-2 cells in the assay used to test intestinal permeability. Using selective inhibitors and transporter knock-out (KO) cells and a targeted Liquid Chromatography tandem Mass Spectrometry (LC-MS) method, we identified 11 metabolites increased in cells with depleted P-glycoprotein (Pgp) activity. Four metabolites were altered with Breast Cancer Resistance (BCRP) inhibition and nine metabolites were identified in the Multidrug Drug Resistance Protein 2 (MRP2) signature. A scoring system was created that could discriminate among the three transporters and validated with additional inhibitors. Pgp and MRP2 substrates did not score as inhibitors. In contrast, BCRP substrates and inhibitors showed a similar intracellular metabolomic signature. Network analysis of signature metabolites led us to investigate changes of enzymes in one-carbon metabolism (folate and methionine cycles). Our data shows that methylenetetrahydrofolate reductase (MTHFR) protein levels increased with Pgp inhibition and Thymidylate synthase (TS) protein levels were reduced with Pgp and MRP2 inhibition. In addition, the methionine cycle is also affected by both Pgp and MRP2 inhibition. In summary, we demonstrated that the routine Caco-2 assay has the potential to identify efflux transporter inhibitors in parallel with substrates in the assays currently used in many DMPK laboratories and that inhibition of efflux transporters has biological consequences.
Assuntos
Proteínas Associadas à Resistência a Múltiplos Medicamentos , Timidilato Sintase , Humanos , Células CACO-2 , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Timidilato Sintase/metabolismo , Metilenotetra-Hidrofolato Redutase (NADPH2) , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Proteínas de Neoplasias/metabolismo , Proteína 2 Associada à Farmacorresistência Múltipla , Proteínas de Membrana Transportadoras , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Permeabilidade , Ácido Fólico , Metionina , Carbono/metabolismoRESUMO
PURPOSE: CT900 is a novel small molecule thymidylate synthase inhibitor that binds to α-folate receptor (α-FR) and thus is selectively taken up by α-FR-overexpressing tumors. PATIENTS AND METHODS: A 3+3 dose escalation design was used. During dose escalation, CT900 doses of 1-6 mg/m2 weekly and 2-12 mg/m2 every 2 weeks (q2Wk) intravenously were evaluated. Patients with high-grade serous ovarian cancer were enrolled in the expansion cohorts. RESULTS: 109 patients were enrolled: 42 patients in the dose escalation and 67 patients in the expansion cohorts. At the dose/schedule of 12 mg/m2/q2Wk (with and without dexamethasone, n = 40), the most common treatment-related adverse events were fatigue, nausea, diarrhea, cough, anemia, and pneumonitis, which were predominantly grade 1 and grade 2. Levels of CT900 more than 600 nmol/L needed for growth inhibition in preclinical models were achieved for >65 hours at a dose of 12 mg/m2. In the expansion cohorts, the overall response rate (ORR), was 14/64 (21.9%). Thirty-eight response-evaluable patients in the expansion cohorts receiving 12 mg/m2/q2Wk had tumor evaluable for quantification of α-FR. Patients with high or medium expression had an objective response rate of 9/25 (36%) compared with 1/13 (7.7%) in patients with negative/very low or low expression of α-FR. CONCLUSIONS: The dose of 12 mg/m2/q2Wk was declared the recommended phase II dose/schedule. At this dose/schedule, CT900 exhibited an acceptable side effect profile with clinical benefit in patients with high/medium α-FR expression and warrants further investigation.
Assuntos
Neoplasias , Neoplasias Ovarianas , Humanos , Feminino , Timidilato Sintase/genética , Dose Máxima Tolerável , Neoplasias/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Ácido FólicoRESUMO
The transcriptional repressor BCL6 is an oncogenic driver found to be deregulated in lymphoid malignancies. Herein, we report the optimization of our previously reported benzimidazolone molecular glue-type degrader CCT369260 to CCT373566, a highly potent probe suitable for sustained depletion of BCL6 in vivo. We observed a sharp degradation SAR, where subtle structural changes conveyed the ability to induce degradation of BCL6. CCT373566 showed modest in vivo efficacy in a lymphoma xenograft mouse model following oral dosing.
Assuntos
Carcinogênese , Regulação Neoplásica da Expressão Gênica , Animais , Humanos , Camundongos , Proteínas Proto-Oncogênicas c-bcl-6/metabolismoRESUMO
To identify new chemical series with enhanced binding affinity to the BTB domain of B-cell lymphoma 6 protein, we targeted a subpocket adjacent to Val18. With no opportunities for strong polar interactions, we focused on attaining close shape complementarity by ring fusion onto our quinolinone lead series. Following exploration of different sized rings, we identified a conformationally restricted core which optimally filled the available space, leading to potent BCL6 inhibitors. Through X-ray structure-guided design, combined with efficient synthetic chemistry to make the resulting novel core structures, a >300-fold improvement in activity was obtained by the addition of seven heavy atoms.
Assuntos
Domínio BTB-POZ , Ligação Proteica , Proteínas Proto-Oncogênicas c-bcl-6RESUMO
We hypothesize that the study of acute protein perturbation in signal transduction by targeted anticancer drugs can predict drug sensitivity of these agents used as single agents and rational combination therapy. We assayed dynamic changes in 52 phosphoproteins caused by an acute exposure (1 hour) to clinically relevant concentrations of seven targeted anticancer drugs in 35 non-small cell lung cancer (NSCLC) cell lines and 16 samples of NSCLC cells isolated from pleural effusions. We studied drug sensitivities across 35 cell lines and synergy of combinations of all drugs in six cell lines (252 combinations). We developed orthogonal machine-learning approaches to predict drug response and rational combination therapy. Our methods predicted the most and least sensitive quartiles of drug sensitivity with an AUC of 0.79 and 0.78, respectively, whereas predictions based on mutations in three genes commonly known to predict response to the drug studied, for example, EGFR, PIK3CA, and KRAS, did not predict sensitivity (AUC of 0.5 across all quartiles). The machine-learning predictions of combinations that were compared with experimentally generated data showed a bias to the highest quartile of Bliss synergy scores (P = 0.0243). We confirmed feasibility of running such assays on 16 patient samples of freshly isolated NSCLC cells from pleural effusions. We have provided proof of concept for novel methods of using acute ex vivo exposure of cancer cells to targeted anticancer drugs to predict response as single agents or combinations. These approaches could complement current approaches using gene mutations/amplifications/rearrangements as biomarkers and demonstrate the utility of proteomics data to inform treatment selection in the clinic.
Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Derrame Pleural , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Inteligência Artificial , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , MutaçãoRESUMO
Human xenografts are extremely useful models to study the biology of human cancers and the effects of novel potential therapies. Deregulation of metabolism, including changes in amino acids (AAs), is a common characteristic of many human neoplasms. Plasma AAs undergo daily variations, driven by circadian endogenous and exogenous factors. We compared AAs concentration in triple negative breast cancer MDA-MB-231 cells and MCF10A non-tumorigenic immortalized breast epithelial cells. We also measured plasma AAs in mice bearing xenograft MDA-MB-231 and compared their levels with non-tumor-bearing control animals over 24 h. In vitro studies revealed that most of AAs were significantly different in MDA-MB-231 cells when compared with MCF10A. Plasma concentrations of 15 AAs were higher in cancer cells, two were lower and four were observed to shift across 24 h. In the in vivo setting, analysis showed that 12 out of 20 AAs varied significantly between tumor-bearing and non-tumor bearing mice. Noticeably, these metabolites peaked in the dark phase in non-tumor bearing mice, which corresponds to the active time of these animals. Conversely, in tumor-bearing mice, the peak time occurred during the light phase. In the early period of the light phase, these AAs were significantly higher in tumor-bearing animals, yet significantly lower in the middle of the light phase when compared with controls. This pilot study highlights the importance of well controlled experiments in studies involving plasma AAs in human breast cancer xenografts, in addition to emphasizing the need for more precise examination of exometabolomic changes using multiple time points.
Assuntos
Aminoácidos/sangue , Ritmo Circadiano/fisiologia , Neoplasias Mamárias Experimentais/fisiopatologia , Neoplasias de Mama Triplo Negativas/fisiopatologia , Aminoácidos/metabolismo , Animais , Neoplasias da Mama/fisiopatologia , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Transplante de Neoplasias , Projetos PilotoRESUMO
Rhabdomyosarcomas are aggressive pediatric soft-tissue sarcomas and include high-risk PAX3-FOXO1 fusion-gene-positive cases. Fibroblast growth factor receptor 4 (FGFR4) is known to contribute to rhabdomyosarcoma progression; here, we sought to investigate the involvement and potential for therapeutic targeting of other FGFRs in this disease. Cell-based screening of FGFR inhibitors with potential for clinical repurposing (NVP-BGJ398, nintedanib, dovitinib, and ponatinib) revealed greater sensitivity of fusion-gene-positive versus fusion-gene-negative rhabdomyosarcoma cell lines and was shown to be correlated with high expression of FGFR2 and its specific ligand, FGF7. Furthermore, patient samples exhibit higher mRNA levels of FGFR2 and FGF7 in fusion-gene-positive versus fusion-gene-negative rhabdomyosarcomas. Sustained intracellular mitogen-activated protein kinase (MAPK) activity and FGF7 secretion into culture media during serum starvation of PAX3-FOXO1 rhabdomyosarcoma cells together with decreased cell viability after genetic silencing of FGFR2 or FGF7 was in keeping with a novel FGF7-FGFR2 autocrine loop. FGFR inhibition with NVP-BGJ398 reduced viability and was synergistic with SN38, the active metabolite of irinotecan. In vivo, NVP-BGJ398 abrogated xenograft growth and warrants further investigation in combination with irinotecan as a therapeutic strategy for fusion-gene-positive rhabdomyosarcomas.
Assuntos
Comunicação Autócrina , Rabdomiossarcoma , Linhagem Celular Tumoral , Criança , Resistencia a Medicamentos Antineoplásicos , Fator 7 de Crescimento de Fibroblastos , Humanos , Irinotecano , Inibidores de Proteínas Quinases/farmacologia , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos , Rabdomiossarcoma/tratamento farmacológico , Rabdomiossarcoma/genéticaRESUMO
OBJECTIVES: Novel therapies, such as, small protein molecule inhibitors and immunotherapies are first tested clinically in Phase I trials. Moving on to later phase trials and ultimately standard practice. A key aim of these early clinical trials is to define a toxicity profile; however, the emphasis is often on safety. The concern is cognitive toxicity is poorly studied in this context and may be under-reported. The aim of this review is to map evidence of cognitive assessment, toxicity, and confounding factors within reports from Phase I trials and consider putative mechanisms of impairment aligned with mechanisms of novel therapies. METHODS: A scoping review methodology was applied to the search of databases, including Embase, MEDLINE, Clinicaltrials.gov. A [keyword search was conducted, results screened for duplication then inclusion/exclusion criteria applied. Articles were further screened for relevance; data organised into categories and charted in a tabular format]. Evidence was collated and summarised into a narrative synthesis. RESULTS: Despite the availability of robust ways to assess cognitive function, these are not routinely included in the conduct of early clinical trials. Reports of cognitive toxicity in early Phase I trials are limited and available evidence on this shows that a proportion of patients experience impaired cognitive function over the course of participating in a Phase I trial. Links are identified between the targeted action of some novel therapies and putative mechanisms of cognitive impairment. CONCLUSION: The review provides rationale for research investigating cognitive function in this context. A study exploring the cognitive function of patients on Phase I trials and the feasibility of formally assessing this within early clinical trials is currently underway at the Royal Marsden.
Assuntos
Cognição , HumanosRESUMO
Somatic mutations in ACVR1 are found in a quarter of children with diffuse intrinsic pontine glioma (DIPG), but there are no ACVR1 inhibitors licensed for the disease. Using an artificial intelligence-based platform to search for approved compounds for ACVR1-mutant DIPG, the combination of vandetanib and everolimus was identified as a possible therapeutic approach. Vandetanib, an inhibitor of VEGFR/RET/EGFR, was found to target ACVR1 (K d = 150 nmol/L) and reduce DIPG cell viability in vitro but has limited ability to cross the blood-brain barrier. In addition to mTOR, everolimus inhibited ABCG2 (BCRP) and ABCB1 (P-gp) transporters and was synergistic in DIPG cells when combined with vandetanib in vitro. This combination was well tolerated in vivo and significantly extended survival and reduced tumor burden in an orthotopic ACVR1-mutant patient-derived DIPG xenograft model. Four patients with ACVR1-mutant DIPG were treated with vandetanib plus an mTOR inhibitor, informing the dosing and toxicity profile of this combination for future clinical studies. SIGNIFICANCE: Twenty-five percent of patients with the incurable brainstem tumor DIPG harbor somatic activating mutations in ACVR1, but there are no approved drugs targeting the receptor. Using artificial intelligence, we identify and validate, both experimentally and clinically, the novel combination of vandetanib and everolimus in these children based on both signaling and pharmacokinetic synergies.This article is highlighted in the In This Issue feature, p. 275.
Assuntos
Receptores de Ativinas Tipo I/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Tronco Encefálico/tratamento farmacológico , Everolimo/uso terapêutico , Glioma/tratamento farmacológico , Piperidinas/uso terapêutico , Quinazolinas/uso terapêutico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias do Tronco Encefálico/mortalidade , Criança , Pré-Escolar , Reposicionamento de Medicamentos , Everolimo/administração & dosagem , Feminino , Glioma/mortalidade , Humanos , Masculino , Camundongos , Camundongos SCID , Piperidinas/administração & dosagem , Quinazolinas/administração & dosagem , Ratos , Resultado do TratamentoRESUMO
We describe the optimization of modestly active starting points to potent inhibitors of BCL6 by growing into a subpocket, which was occupied by a network of five stably bound water molecules. Identifying potent inhibitors required not only forming new interactions in the subpocket but also perturbing the water network in a productive, potency-increasing fashion while controlling the physicochemical properties. We achieved this goal in a sequential manner by systematically probing the pocket and the water network, ultimately achieving a 100-fold improvement of activity. The most potent compounds displaced three of the five initial water molecules and formed hydrogen bonds with the remaining two. Compound 25 showed a promising profile for a lead compound with submicromolar inhibition of BCL6 in cells and satisfactory pharmacokinetic (PK) properties. Our work highlights the importance of finding productive ways to perturb existing water networks when growing into solvent-filled protein pockets.
Assuntos
Antineoplásicos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-6/antagonistas & inibidores , Antineoplásicos/química , Cristalografia por Raios X , Desenho de Fármacos , Humanos , Ligação de Hidrogênio , Solubilidade , Relação Estrutura-AtividadeRESUMO
Recurrence of prostate cancer after radical prostatectomy is a consequence of incomplete tumor resection. Systemic chemotherapy after surgery is associated with significant toxicity. Improved delivery methods for toxic drugs capable of targeting positive resection margins can reduce tumor recurrence and avoid their known toxicity. This study evaluates the effectiveness and toxicity of docetaxel (DTX) release from highly porous biodegradable microparticles intended for delivery into the tissue cavity created during radical prostatectomy to target residual tumor cells. The microparticles, composed of poly(dl-lactide-co-glycolide) (PLGA), are processed using thermally induced phase separation (TIPS) and loaded with DTX via antisolvent precipitation. Sustained drug release and effective toxicity in vitro are observed against PC3 human prostate cells. Peritumoral injection in a PC3 xenograft tumor model results in tumor growth inhibition equivalent to that achieved with intravenous delivery of DTX. Unlike intravenous delivery of DTX, implantation of DTX-TIPS microparticles is not accompanied by toxicity or elevated systemic levels of DTX in organ tissues or plasma. DTX-TIPS microparticles provide localized and sustained release of nontoxic therapeutic amounts of DTX. This may offer novel therapeutic strategies for improving management of patients with clinically localized high-risk disease requiring radical prostatectomy and other solid cancers at high risk of positive resection margins.