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1.
PLoS Biol ; 22(5): e3002617, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38696533

RESUMO

BAK and BAX execute intrinsic apoptosis by permeabilising the mitochondrial outer membrane. Their activity is regulated through interactions with pro-survival BCL-2 family proteins and with non-BCL-2 proteins including the mitochondrial channel protein VDAC2. VDAC2 is important for bringing both BAK and BAX to mitochondria where they execute their apoptotic function. Despite this important function in apoptosis, while interactions with pro-survival family members are well characterised and have culminated in the development of drugs that target these interfaces to induce cancer cell apoptosis, the interaction between BAK and VDAC2 remains largely undefined. Deep scanning mutagenesis coupled with cysteine linkage identified key residues in the interaction between BAK and VDAC2. Obstructive labelling of specific residues in the BH3 domain or hydrophobic groove of BAK disrupted this interaction. Conversely, mutating specific residues in a cytosol-exposed region of VDAC2 stabilised the interaction with BAK and inhibited BAK apoptotic activity. Thus, this VDAC2-BAK interaction site can potentially be targeted to either inhibit BAK-mediated apoptosis in scenarios where excessive apoptosis contributes to disease or to promote BAK-mediated apoptosis for cancer therapy.


Assuntos
Apoptose , Canal de Ânion 2 Dependente de Voltagem , Proteína Killer-Antagonista Homóloga a bcl-2 , Canal de Ânion 2 Dependente de Voltagem/metabolismo , Canal de Ânion 2 Dependente de Voltagem/genética , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteína Killer-Antagonista Homóloga a bcl-2/genética , Humanos , Ligação Proteica , Mitocôndrias/metabolismo , Animais , Células HEK293
2.
Cell Metab ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38718793

RESUMO

Obesity alters levels of pituitary hormones that govern hepatic immune-metabolic homeostasis, dysregulation of which leads to nonalcoholic fatty liver disease (NAFLD). However, the impact of obesity on intra-pituitary homeostasis is largely unknown. Here, we uncovered a blunted unfolded protein response (UPR) but elevated inflammatory signatures in pituitary glands of obese mice and humans. Furthermore, we found that obesity inflames the pituitary gland, leading to impaired pituitary inositol-requiring enzyme 1α (IRE1α)-X-box-binding protein 1 (XBP1) UPR branch, which is essential for protecting against pituitary endocrine defects and NAFLD progression. Intriguingly, pituitary IRE1-deletion resulted in hypothyroidism and suppressed the thyroid hormone receptor B (THRB)-mediated activation of Xbp1 in the liver. Conversely, activation of the hepatic THRB-XBP1 axis improved NAFLD in mice with pituitary UPR defect. Our study provides the first evidence and mechanism of obesity-induced intra-pituitary cellular defects and the pathophysiological role of pituitary-liver UPR communication in NAFLD progression.

3.
Methods Mol Biol ; 2660: 357-372, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37191809

RESUMO

Traditionally, disease causal mutations were thought to disrupt gene function. However, it becomes more clear that many deleterious mutations could exhibit a "gain-of-function" (GOF) behavior. Systematic investigation of such mutations has been lacking and largely overlooked. Advances in next-generation sequencing have identified thousands of genomic variants that perturb the normal functions of proteins, further contributing to diverse phenotypic consequences in disease. Elucidating the functional pathways rewired by GOF mutations will be crucial for prioritizing disease-causing variants and their resultant therapeutic liabilities. In distinct cell types (with varying genotypes), precise signal transduction controls cell decision, including gene regulation and phenotypic output. When signal transduction goes awry due to GOF mutations, it would give rise to various disease types. Quantitative and molecular understanding of network perturbations by GOF mutations may provide explanations for 'missing heritability" in previous genome-wide association studies. We envision that it will be instrumental to push current paradigm toward a thorough functional and quantitative modeling of all GOF mutations and their mechanistic molecular events involved in disease development and progression. Many fundamental questions pertaining to genotype-phenotype relationships remain unresolved. For example, which GOF mutations are key for gene regulation and cellular decisions? What are the GOF mechanisms at various regulation levels? How do interaction networks undergo rewiring upon GOF mutations? Is it possible to leverage GOF mutations to reprogram signal transduction in cells, aiming to cure disease? To begin to address these questions, we will cover a wide range of topics regarding GOF disease mutations and their characterization by multi-omic networks. We highlight the fundamental function of GOF mutations and discuss the potential mechanistic effects in the context of signaling networks. We also discuss advances in bioinformatic and computational resources, which will dramatically help with studies on the functional and phenotypic consequences of GOF mutations.


Assuntos
Multiômica , Medicina de Precisão , Estudo de Associação Genômica Ampla , Mutação , Mutação com Ganho de Função
4.
Transl Lung Cancer Res ; 12(2): 257-265, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36895920

RESUMO

Background: Identifying a circulating biomarker predictive of immune checkpoint inhibitor (ICI) benefit in patients with small cell lung cancer (SCLC) remains an unmet need. Characteristics of peripheral and intratumoral T-cell receptor (TCR) repertoires have been shown to predict clinical outcomes in non-small cell lung cancer (NSCLC). Recognizing a knowledge gap, we sought to characterize circulating TCR repertoires and their relationship with clinical outcomes in SCLC. Methods: SCLC patients with limited (n=4) and extensive (n=10) stage disease were prospectively enrolled for blood collection and chart review. Targeted next-generation sequencing of TCR beta and alpha chains of peripheral blood samples was performed. Unique TCR clonotypes were defined by identical CDR3, V gene, and J gene nucleotide sequences of the beta chain and subsequently used to calculate TCR diversity indices. Results: Patients with stable versus progressive and limited versus extensive stage disease did not demonstrate significant differences in V gene usage. Kaplan-Meier curve and log-rank analysis did not identify a statistical difference in progression-free survival (PFS) (P=0.900) or overall survival (OS) (P=0.200) between high and low on-treatment TCR diversity groups, although the high diversity group exhibited a trend toward increased OS. Conclusions: We report the second study investigating peripheral TCR repertoire diversity in SCLC. With a limited sample size, no statistically significant associations between peripheral TCR diversity and clinical outcomes were observed, though further study is warranted.

5.
Nat Med ; 28(11): 2353-2363, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36357680

RESUMO

Circulating tumor DNA (ctDNA) sequencing guides therapy decisions but has been studied mostly in small cohorts without sufficient follow-up to determine its influence on overall survival. We prospectively followed an international cohort of 1,127 patients with non-small-cell lung cancer and ctDNA-guided therapy. ctDNA detection was associated with shorter survival (hazard ratio (HR), 2.05; 95% confidence interval (CI), 1.74-2.42; P < 0.001) independently of clinicopathologic features and metabolic tumor volume. Among the 722 (64%) patients with detectable ctDNA, 255 (23%) matched to targeted therapy by ctDNA sequencing had longer survival than those not treated with targeted therapy (HR, 0.63; 95% CI, 0.52-0.76; P < 0.001). Genomic alterations in ctDNA not detected by time-matched tissue sequencing were found in 25% of the patients. These ctDNA-only alterations disproportionately featured subclonal drivers of resistance, including RICTOR and PIK3CA alterations, and were associated with short survival. Minimally invasive ctDNA profiling can identify heterogeneous drivers not captured in tissue sequencing and expand community access to life-prolonging therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , DNA Tumoral Circulante , Neoplasias Pulmonares , Humanos , DNA Tumoral Circulante/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Biomarcadores Tumorais/genética , Mutação , Sequenciamento de Nucleotídeos em Larga Escala
6.
Transl Lung Cancer Res ; 11(8): 1578-1590, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36090640

RESUMO

Background: Cell free DNA (cfDNA) is an exciting biomarker with applications across the cancer care continuum. Determinants of cfDNA shedding dynamics remain an active research area. We performed a detailed analysis of tumor volume and factors associated with detection of cfDNA mutations. Methods: Patients with advanced non-small cell lung cancers (NSCLCs) were prospectively enrolled on a plasma biomarker protocol. Next generation sequencing (NGS) was performed using a validated, bias-corrected, hybrid-capture panel assay of lung cancer-associated genes. Volume of tumor in different subsites and total tumor volume were determined through manual volume delineation using PET/CT and brain magnetic resonance imaging (MRI) imaging. The primary endpoint was detection of cfDNA mutation; secondary endpoints were overall survival (OS) and variant allele frequency (VAF). Results: There were 110 patients included, 78 of whom had at least one mutation detected. Median total tumor volume for the entire cohort, patients with mutation detected, and patients with no mutation detected were 66 mL (range, 2-1,383 mL), 76 mL (range, 5-1,383 mL), and 45 mL (range, 2-460 mL), respectively (P=0.002; mutation detected vs. not). The optimal total tumor volume threshold to predict increased probability of mutation detection was 65 mL (P=0.006). Total tumor volume greater than 65 mL was a significant predictor of mutation detection on multivariate analysis (OR: 4.30, P=0.003). Significant predictors of OS were age (HR: 1.04, P=0.002), detection of cfDNA mutation (HR: 2.11, P=0.024), and presence of bone metastases (HR: 1.66, P=0.047). Conclusions: Total tumor volume greater than 65 mL was associated with cfDNA mutation detection in patients with advanced NSCLC.

7.
Vet Clin Pathol ; 51(3): 356-375, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35608195

RESUMO

BACKGROUND: Clinical pathology and body weight information for the cynomolgus monkey in the literature is primarily derived from a small number of animals with limited age ranges, varying geographic origins, and mixed genders. OBJECTIVES: This study aimed to summarize the age- and sex-related changes in clinical pathology analytes and body weights in cynomolgus monkeys of Mauritian origin. METHODS: Pre-study age and body weight data were reviewed in 1819 animals, and pre-study hematologic, coagulation, and serum biochemical analytes were reviewed in 1664 animals. RESULTS: Body weights were statistically higher (P < 0.01) in males than females in all age groups (2-10 years). These measurements became prominent after 4 years of age and peaked at 7 to 8 years of age in both sexes. Sex-related differences were noted in reticulocyte (RETIC) counts, creatinine, cholesterol, and triglyceride concentrations, and alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT) activities. Age-related differences were noted in RETIC and lymphocyte counts, creatinine, triglyceride, phosphorus, and globulin concentrations, and ALP and GGT activities. The youngest (2 to <3 year) age group had the fewest number of clinical pathologic analyte differences including ALP and GGT activity differences which occurred in all age groups from 2 to 10 years; they also had age-related lower globulin concentrations. There were no age- or sex-related differences in coagulation measurands. CONCLUSIONS: Sexual dimorphism in body weight was apparent for all ages from 2 to 10 years of age. The only difference in clinical pathology analytes unique to the 2 to <3 years of age group were age-related lower globulin levels.


Assuntos
Globulinas , Patologia Clínica , Animais , Peso Corporal , Creatinina , Feminino , Macaca fascicularis , Masculino , Maurício , Triglicerídeos
9.
Surg Endosc ; 36(7): 4946-4955, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34731300

RESUMO

INTRODUCTION: Bariatric surgery is the most effective modality to stably reduce weight and related comorbidities in patients suffering from class II and III obesity. Data comparing long-term safety and efficacy of the three most effective bariatric operations are limited in patients with BMI ≥ 50 kg/m2, which complicate shared surgeon-patient decision making regarding optimal procedure selection. METHODS: A retrospective analysis was performed on all patients with BMI ≥ 50 kg/m2 who underwent biliopancreatic diversion with duodenal switch (BPD/DS), Roux-en-Y gastric bypass (RYGB), or sleeve gastrectomy (SG) at our institution between 2009 and 2019. Data collected from patients' electronic medical records included operative details as well as BMI and presence and resolution of obesity-related comorbidities at 0, 6, 12, 24, 48, and 60 months post-operatively. RESULTS: Among 537 patients with BMI ≥ 50 kg/m2 who had a primary bariatric procedure, 93 patients underwent BPD/DS (17.3%), 341 patients underwent RYGB (63.5%), and 103 patients underwent SG (19.2%). BMI decreased by 23.7 kg/m2 in BPD/DS, 14.7 kg/m2 in RYGB, and 13.6 kg/m2 in SG cohorts at 60 months post-operatively (p < 0.0001). The greatest %TWL occurred in BPD/DS cohort (38.4%) followed by the RYGB (26.3%) and SG (23.6%) cohorts (p < 0.0001). The thirty-day complication rate was 12.9% for BPD/DS, 4.7% for RYGB, and 8.7% for SG (p = 0.015). CONCLUSIONS: Our study demonstrated that the BPD/DS is the most effective operation at long-term reduction of BMI and achieved highest %TWL while SG and RYGB had similar results at 60 months post-op. BPD/DS is associated with increased early and late surgical complications compared to RYGB and SG.


Assuntos
Desvio Biliopancreático , Derivação Gástrica , Obesidade Mórbida , Desvio Biliopancreático/métodos , Índice de Massa Corporal , Gastrectomia/métodos , Derivação Gástrica/métodos , Humanos , Obesidade/cirurgia , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Estudos Retrospectivos , Redução de Peso
10.
Cell Rep ; 37(7): 110003, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34788615

RESUMO

Brown adipose tissue (BAT) thermogenic activity is tightly regulated by cellular redox status, but the underlying molecular mechanisms are incompletely understood. Protein S-nitrosylation, the nitric-oxide-mediated cysteine thiol protein modification, plays important roles in cellular redox regulation. Here we show that diet-induced obesity (DIO) and acute cold exposure elevate BAT protein S-nitrosylation, including UCP1. This thermogenic-induced nitric oxide bioactivity is regulated by S-nitrosoglutathione reductase (GSNOR; alcohol dehydrogenase 5 [ADH5]), a denitrosylase that balances the intracellular nitroso-redox status. Loss of ADH5 in BAT impairs cold-induced UCP1-dependent thermogenesis and worsens obesity-associated metabolic dysfunction. Mechanistically, we demonstrate that Adh5 expression is induced by the transcription factor heat shock factor 1 (HSF1), and administration of an HSF1 activator to BAT of DIO mice increases Adh5 expression and significantly improves UCP1-mediated respiration. Together, these data indicate that ADH5 controls BAT nitroso-redox homeostasis to regulate adipose thermogenesis, which may be therapeutically targeted to improve metabolic health.


Assuntos
Tecido Adiposo Marrom/metabolismo , Álcool Desidrogenase/metabolismo , Óxido Nítrico/metabolismo , Álcool Desidrogenase/fisiologia , Animais , Dieta , Células HEK293 , Homeostase/fisiologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Obesos , Óxido Nítrico/química , Obesidade/metabolismo , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Termogênese/fisiologia , Proteína Desacopladora 1/metabolismo , Proteína Desacopladora 1/fisiologia
11.
Nature ; 599(7886): 679-683, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34759319

RESUMO

Inactive state-selective KRAS(G12C) inhibitors1-8 demonstrate a 30-40% response rate and result in approximately 6-month median progression-free survival in patients with lung cancer9. The genetic basis for resistance to these first-in-class mutant GTPase inhibitors remains under investigation. Here we evaluated matched pre-treatment and post-treatment specimens from 43 patients treated with the KRAS(G12C) inhibitor sotorasib. Multiple treatment-emergent alterations were observed across 27 patients, including alterations in KRAS, NRAS, BRAF, EGFR, FGFR2, MYC and other genes. In preclinical patient-derived xenograft and cell line models, resistance to KRAS(G12C) inhibition was associated with low allele frequency hotspot mutations in KRAS(G12V or G13D), NRAS(Q61K or G13R), MRAS(Q71R) and/or BRAF(G596R), mirroring observations in patients. Single-cell sequencing in an isogenic lineage identified secondary RAS and/or BRAF mutations in the same cells as KRAS(G12C), where they bypassed inhibition without affecting target inactivation. Genetic or pharmacological targeting of ERK signalling intermediates enhanced the antiproliferative effect of G12C inhibitor treatment in models with acquired RAS or BRAF mutations. Our study thus suggests a heterogenous pattern of resistance with multiple subclonal events emerging during G12C inhibitor treatment. A subset of patients in our cohort acquired oncogenic KRAS, NRAS or BRAF mutations, and resistance in this setting may be delayed by co-targeting of ERK signalling intermediates. These findings merit broader evaluation in prospective clinical trials.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Mutação , Neoplasias/tratamento farmacológico , Neoplasias/genética , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética , Acetonitrilas/farmacologia , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular , Estudos de Coortes , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Piridinas/farmacologia , Piridinas/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Mol Ther Nucleic Acids ; 26: 307-320, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34513312

RESUMO

Micropeptides (microproteins) encoded by transcripts previously annotated as long noncoding RNAs (lncRNAs) are emerging as important mediators of fundamental biological processes in health and disease. Here, we applied two computational tools to identify putative micropeptides encoded by lncRNAs that are expressed in the human pancreas. We experimentally verified one such micropeptide encoded by a ß cell- and neural cell-enriched lncRNA TCL1 Upstream Neural Differentiation-Associated RNA (TUNAR, also known as TUNA, HI-LNC78, or LINC00617). We named this highly conserved 48-amino-acid micropeptide beta cell- and neural cell-regulin (BNLN). BNLN contains a single-pass transmembrane domain and localizes at the endoplasmic reticulum (ER) in pancreatic ß cells. Overexpression of BNLN lowered ER calcium levels, maintained ER homeostasis, and elevated glucose-stimulated insulin secretion in pancreatic ß cells. We further assessed the BNLN expression in islets from mice fed a high-fat diet and a regular diet and found that BNLN is suppressed by diet-induced obesity (DIO). Conversely, overexpression of BNLN enhanced insulin secretion in islets from lean and obese mice as well as from humans. Taken together, our study provides the first evidence that lncRNA-encoded micropeptides play a critical role in pancreatic ß cell functions and provides a foundation for future comprehensive analyses of micropeptide function and pathophysiological impact on diabetes.

14.
Lung Cancer ; 159: 66-73, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34311346

RESUMO

OBJECTIVES: Liquid biopsy for plasma circulating tumor DNA (ctDNA) next-generation sequencing (NGS) can detect ALK fusions, though data on clinical utility of this technology in the real world is limited. MATERIALS AND METHODS: Patients with lung cancer without known oncogenic drivers or who had acquired resistance to therapy (n = 736) underwent prospective plasma ctDNA NGS. A subset of this cohort (n = 497) also had tissue NGS. We evaluated ALK fusion detection, turnaround time (TAT), plasma and tissue concordance, matching to therapy, and treatment response. RESULTS: ctDNA identified an ALK fusion in 21 patients (3%) with a variety of breakpoints and fusion partners, including EML4, CLTC, and PON1, a novel ALK fusion partner. TAT for ctDNA NGS was shorter than tissue NGS (10 vs. 20 days; p < 0.001). Among ALK fusions identified by ctDNA, 93% (13/14, 95% CI 66%-99%) were concordant with tissue evaluation. Among ALK fusions detected by tissue NGS, 54% (13/24, 95% CI 33%-74%) were concordant with plasma ctDNA. ctDNA matched patients to ALK-directed therapy with subsequent clinical response, including four patients matched on the basis of ctDNA results alone due to inadequate or delayed tissue testing. Serial ctDNA analysis detected MET amplification (n = 2) and ALK G1202R mutation (n = 2) as mechanisms of acquired resistance to ALK-directed therapy. CONCLUSION: Our findings support a complementary role for ctDNA in detection of ALK fusions and other alterations at diagnosis and therapeutic resistance settings.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , DNA Tumoral Circulante , Neoplasias Pulmonares , Arildialquilfosfatase , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , DNA Tumoral Circulante/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Mutação , Estudos Prospectivos , Receptores Proteína Tirosina Quinases/genética
15.
Clin Cancer Res ; 27(16): 4539-4548, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34112710

RESUMO

PURPOSE: In the placebo-controlled SPARTAN study, apalutamide added to androgen-deprivation therapy (ADT) improved metastasis-free survival, second progression-free survival (PFS2), and overall survival (OS) in patients with nonmetastatic castration-resistant prostate cancer (nmCRPC). Mechanisms of resistance to apalutamide in nmCRPC require evaluation. PATIENTS AND METHODS: In a subset of patients from SPARTAN, aberrations were assessed at baseline and end of study treatment (EOST) using targeted next-generation sequencing or qRT-PCR. Circulating-tumor DNA (ctDNA) levels were assessed qualitatively. Select aberrations in androgen receptor (AR) and other common PC-driving genes were detected and summarized by the treatment group; genomic aberrations were summarized in ctDNA-positive samples. Association between detection of aberrations in all patients and outcomes was assessed using Cox proportional-hazards models and multivariate analysis. RESULTS: In 247 patients, the overall prevalence of ctDNA, AR aberrations, and TP53 inactivation increased from baseline (40.6%, 13.6%, and 22.2%) to EOST (57.1%, 25.4%, and 35.0%) and was comparable between treatment groups at EOST. In patients who received subsequent androgen signaling inhibition after study treatment, detectable biomarkers at EOST were significantly associated with poor outcomes: ctDNA with PFS2 or OS (HR, 2.01 or 2.17, respectively; P < 0.0001 for both), any AR aberration with PFS2 (1.74; P = 0.024), and TP53 or BRCA2 inactivation with OS (2.06; P = 0.003; or 3.1; P < 0.0001). CONCLUSIONS: Apalutamide plus ADT did not increase detectable AR/non-AR aberrations over ADT alone. Detectable ctDNA, AR aberrations, and TP53/BRCA2 inactivation at EOST were associated with poor outcomes in patients treated with first subsequent androgen signaling inhibitor.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Biomarcadores Tumorais/sangue , Neoplasias de Próstata Resistentes à Castração/sangue , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Tioidantoínas/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Quimioterapia Combinada , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias de Próstata Resistentes à Castração/mortalidade , Neoplasias de Próstata Resistentes à Castração/patologia , Medição de Risco , Taxa de Sobrevida
16.
N Engl J Med ; 384(25): 2382-2393, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34161704

RESUMO

BACKGROUND: Clinical trials of the KRAS inhibitors adagrasib and sotorasib have shown promising activity in cancers harboring KRAS glycine-to-cysteine amino acid substitutions at codon 12 (KRASG12C). The mechanisms of acquired resistance to these therapies are currently unknown. METHODS: Among patients with KRASG12C -mutant cancers treated with adagrasib monotherapy, we performed genomic and histologic analyses that compared pretreatment samples with those obtained after the development of resistance. Cell-based experiments were conducted to study mutations that confer resistance to KRASG12C inhibitors. RESULTS: A total of 38 patients were included in this study: 27 with non-small-cell lung cancer, 10 with colorectal cancer, and 1 with appendiceal cancer. Putative mechanisms of resistance to adagrasib were detected in 17 patients (45% of the cohort), of whom 7 (18% of the cohort) had multiple coincident mechanisms. Acquired KRAS alterations included G12D/R/V/W, G13D, Q61H, R68S, H95D/Q/R, Y96C, and high-level amplification of the KRASG12C allele. Acquired bypass mechanisms of resistance included MET amplification; activating mutations in NRAS, BRAF, MAP2K1, and RET; oncogenic fusions involving ALK, RET, BRAF, RAF1, and FGFR3; and loss-of-function mutations in NF1 and PTEN. In two of nine patients with lung adenocarcinoma for whom paired tissue-biopsy samples were available, histologic transformation to squamous-cell carcinoma was observed without identification of any other resistance mechanisms. Using an in vitro deep mutational scanning screen, we systematically defined the landscape of KRAS mutations that confer resistance to KRASG12C inhibitors. CONCLUSIONS: Diverse genomic and histologic mechanisms impart resistance to covalent KRASG12C inhibitors, and new therapeutic strategies are required to delay and overcome this drug resistance in patients with cancer. (Funded by Mirati Therapeutics and others; ClinicalTrials.gov number, NCT03785249.).


Assuntos
Acetonitrilas/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pulmonares/tratamento farmacológico , Mutação , Piperazinas/uso terapêutico , Proteínas Proto-Oncogênicas p21(ras)/genética , Pirimidinas/uso terapêutico , Neoplasias do Apêndice/tratamento farmacológico , Neoplasias do Apêndice/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Colorretais/genética , Humanos , Neoplasias Pulmonares/genética , Conformação Proteica , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/ultraestrutura , Piridinas/uso terapêutico
17.
Autophagy ; 17(8): 1841-1855, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32597296

RESUMO

Defective macroautophagy/autophagy and a failure to initiate the adaptive unfolded protein response (UPR) in response to the endoplasmic reticulum (ER) stress contributes to obesity-associated metabolic dysfunction. However, whether and how unresolved ER stress leads to defects in the autophagy pathway and to the progression of obesity-associated hepatic pathologies remains unclear. Obesity suppresses the expression of hepatic spliced XBP1 (X-box binding protein 1; sXBP1), the key transcription factor that promotes the adaptive UPR. Our RNA-seq analysis revealed that sXBP1 regulates genes involved in lysosomal function in the liver under fasting conditions. Chromatin immunoprecipitation (ChIP) analyzes of both primary hepatocytes and whole livers further showed that sXBP1 occupies the -743 to -523 site of the promoter of Tfeb (transcription factor EB), a master regulator of autophagy and lysosome biogenesis. Notably, this occupancy was significantly reduced in livers from patients with steatosis. In mice, hepatic deletion of Xbp1 (xbp1 LKO) suppressed the transcription of Tfeb as well as autophagy, whereas hepatic overexpression of sXbp1 enhanced Tfeb transcription and autophagy. Moreover, overexpression of Tfeb in the xbp1 LKO mouse liver ameliorated glucose intolerance and steatosis in mice with diet-induced obesity (DIO). Conversely, loss of TFEB function impaired the protective role of sXBP1 in hepatic steatosis in mice with DIO. These data indicate that sXBP1-Tfeb signaling has direct functional consequences in the context of obesity. Collectively, our data provide novel insight into how two organelle stress responses are integrated to protect against obesity-associated metabolic dysfunction.Abbreviations: AAV8: adeno-associated virus serotype 8; ACTB: actin, beta; ANOVA: analysis of variance; ATF6: activating transcription factor-6; ATG: autophagy related; BECN1: beclin 1; BMI: body mass index; ChIP: chromatin immunoprecipitation; CLEAR: coordinated lysosomal expression and regulation; Cre: cre recombinase; DIO: diet-induced obesity; EBSS: Earle's balanced salt solution; EIF2AK3/PERK: eukaryotic translation initiation factor 2 alpha kinase 3; ER: endoplasmic reticulum; ERN1/IRE1: endoplasmic reticulum (ER) to nucleus signaling 1; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GFP: green fluorescent protein; HFD: high-fat diet; h: hours; HSCs: hepatic stellate cells; INS: insulin; L/A: ammonium chloride and leupeptin; MAP1LC3B/LC3B: microtubule-associated protein 1 light chain 3 beta; mRNA: messenger RNA; NAFLD: nonalcoholic fatty liver disease; NASH: nonalcoholic steatohepatitis; RD: regular diet; RFP: red fluorescent protein; SERPINA7/TBG: serpin family A member 7; SQSTM1/p62: sequestome 1; sXbp1 LOE: liver-specific overexpression of spliced Xbp1; TFEB: transcription factor EB; TG: thapsigargin; TN: tunicamycin; UPR: unfolded protein response; wks: weeks; WT: wild type; XBP1: X-box binding protein 1; xbp1 LKO: liver-specific Xbp1 knockout.


Assuntos
Autofagia/fisiologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Proteína 1 de Ligação a X-Box/metabolismo , Animais , Autofagia/genética , Estresse do Retículo Endoplasmático , Humanos , Fígado/metabolismo , Lisossomos/metabolismo , Camundongos , Resposta a Proteínas não Dobradas/fisiologia
18.
Stem Cells Transl Med ; 10(3): 385-397, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33098750

RESUMO

To optimize the regenerative proficiency of stem cells, a cardiopoietic protein-based cocktail consisting of multiple growth factors has been developed and advanced into clinical trials for treatment of ischemic heart failure. Streamlining the inductors of cardiopoiesis would address the resource intensive nature of the current stem cell enhancement protocol. To this end, the microencapsulated-modified-mRNA (M3 RNA) technique was here applied to introduce early cardiogenic genes into human adipose-derived mesenchymal stem cells (AMSCs). A single mesodermal transcription factor, Brachyury, was sufficient to trigger high expression of cardiopoietic markers, Nkx2.5 and Mef2c. Engineered cardiopoietic stem cells (eCP) featured a transcriptome profile distinct from pre-engineered AMSCs. In vitro, eCP demonstrated protective antioxidant capacity with enhanced superoxide dismutase expression and activity; a vasculogenic secretome driving angiogenic tube formation; and macrophage polarizing immunomodulatory properties. In vivo, in a murine model of myocardial infarction, intramyocardial delivery of eCP (600 000 cells per heart) improved cardiac performance and protected against decompensated heart failure. Thus, heart repair competent stem cells, armed with antioxidant, vasculogenic, and immunomodulatory traits, are here engineered through a protein-independent single gene manipulation, expanding the available regenerative toolkit.


Assuntos
Proteínas Fetais , Insuficiência Cardíaca , Transplante de Células-Tronco Mesenquimais , Células-Tronco , Proteínas com Domínio T , Tecido Adiposo/citologia , Animais , Proteínas Fetais/genética , Insuficiência Cardíaca/terapia , Humanos , Camundongos , Infarto do Miocárdio/terapia , Secretoma , Proteínas com Domínio T/genética , Transcriptoma
19.
Nucl Med Biol ; 90-91: 23-30, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32957056

RESUMO

INTRODUCTION: Radiolabeling of stem cells with a positron emitting radioisotope represents a major advancement in regenerative biotherapy enabling non-invasive imaging. To assess the value of such an approach in a clinically relevant scenario, the tolerability and therapeutic aptitude of [89Zr]zirconium-p-isothiocyanatobenzyl-desferrioxamine ([89Zr]Zr-DBN) labeled human cardiopoietic stem cells (CPs) were evaluated in a model of ischemic heart failure. METHODS AND RESULTS: [89Zr]Zr-DBN based radiolabeling of human CPs yielded [89Zr]Zr-DBN-CPs with radioactivity yield of 0.70 ± 0.20 MBq/106 cells and excellent label stability. Compared to unlabeled cell counterparts, [89Zr]Zr-DBN-CPs maintained morphology, viability, and proliferation capacity with characteristic expression of mesodermal and pro-cardiogenic transcription factors defining the cardiopoietic phenotype. Administered in chronically infarcted murine hearts, [89Zr]Zr-DBN-CPs salvaged cardiac pump failure, documented by improved left ventricular ejection fraction not inferior to unlabeled CPs and notably superior to infarcted hearts without cell treatment. CONCLUSION: The present study establishes that [89Zr]Zr-DBN labeling does not compromise stem cell identity or efficacy in the setting of heart failure, offering a non-invasive molecular imaging platform to monitor regenerative biotherapeutics post-transplantation.


Assuntos
Desferroxamina/análogos & derivados , Insuficiência Cardíaca/patologia , Isotiocianatos/química , Radioisótopos/química , Células-Tronco/metabolismo , Zircônio/química , Animais , Desferroxamina/química , Camundongos , Tomografia por Emissão de Pósitrons , Coloração e Rotulagem , Células-Tronco/patologia , Volume Sistólico
20.
Oncologist ; 25(8): 641-649, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32558067

RESUMO

Since its discovery in 2007, we have seen the lives of patients diagnosed with advanced anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancers (NSCLC) transform with the advent of molecular therapies with first-, second-, and third-generation ALK inhibitors now available in the clinic. Despite great gains in patient survival now measured in years and preserved quality of life with targeted therapies, drug resistance is unfortunately inevitably encountered in this rare and unique molecular subset of lung cancer, and patients will eventually succumb to the disease. As these patients are often young, fit, and never smokers, the clinical and scientific communities have aligned to expedite drug development and access. Drug resistance profiling and further strategies are being explored through clinical trials, including the evaluation of specific drug sequencing and combinations to overcome such resistance and promote patient longevity. The cases of this report focus on precision medicine and aim to portray the pertinent aspects to consider when treating ALK-rearranged NSCLC in 2020, an ever-shifting space. By way of case examples, this report offers valuable information to the treating clinician, including the evolution of systemic treatments and the management of oligo-progression and multisite drug resistance. With the maturation of real-world data, we are fortunate to be experiencing quality and length of life for patients with this disease surpassing prior expectations in advanced lung cancer. KEY POINTS: This report focuses on the importance of genetic analysis of serial biopsies to capture the dynamic therapeutic vulnerabilities of a patient's tumor, providing a perspective on the complexity of ALK tyrosine kinase inhibitor (ALKi) treatment sequencing. These case examples contribute to the literature on ALK-rearranged and oncogene addicted non-small cell lung cancer (NSCLC), providing a framework for care in the clinic. In oligo-progressive disease, local ablative therapy and continuation of ALKi postprogression should be considered with potential for sustained disease control. ALK G1202R kinase domain mutations (KDM), highly prevalent at resistance to second-generation ALKi resistances, may emerge in non-EML4-ALK variant 3 cases and is sensitive to third-generation lorlatinib. When in compound with one or more ALK KDMs, resistance to lorlatinib is expected. In the case of rampantly progressive disease, rebiopsy and redefining biology in a timely manner may be informative.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Quinase do Linfoma Anaplásico/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Qualidade de Vida
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