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Germline BRCA1/2 variants in comprehensive genomic profiling (CGP) often exhibit variant allele frequency (VAF) exceeding 50%. However, when genomic loss occurs at the ipsilateral allele, including the germline variant in tumor cells, the VAF is low. This case report presents a patient with uterine sarcoma with a pathogenic BRCA2 mutation and low VAF in tumor-only CGP, which was later identified as a germline variant. When genomic alterations in BRCA1/2 are identified in tumor-only CGP, the possible germline origin of the variants should be considered, even if their VAF is very low.
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Proteína BRCA2 , Sarcoma , Humanos , Proteína BRCA2/genética , Proteína BRCA1/genética , Predisposição Genética para Doença , Frequência do Gene , Genômica , Células Germinativas , Mutação em Linhagem GerminativaRESUMO
The KEAP1-NRF2 system induces the expression of antioxidant genes in response to various types of oxidative stress. Some cancer cells activate this system, which increases their malignancy through genetic mutations. We performed a retrospective cohort study using the C-CAT database, which contains the gene-panel sequence data from 60,056 cases of diagnosed solid tumors. We analyzed somatic mutations in NRF2 and KEAP1 genes and their associations with clinical outcomes. Variants in the NRF2 gene were clustered in exon 2, which encodes the DLG and ETGE motifs essential for KEAP1 interaction. The NRF2 variants were frequently observed in esophageal and lung squamous cell carcinoma with frequencies of 35.9% and 19.6%, respectively. Among these mutations, the NRF2 variants in the ETGE motif were indicators of a worse prognosis. KEAP1 variants were found in 2.5% of all cases. The variants were frequent in lung cancer and showed a worse prognosis in lung and other types of adenocarcinomas. We then conducted gene expression analysis using TCGA data. While cancers with DLG and ETGE variants were similar in terms of gene expression profiles, there were significant differences between cancers with KEAP1 and NRF2 variants. Our results indicate that genetic alteration of the KEAP1-NRF2 pathway is a major factor in patient prognosis for each cancer type and its genetic variant. Variants in NRF2 and KEAP1 genes can characterize the biological basis of each cancer type and are involved in carcinogenesis, resistance to therapy, and other biological differences.
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Cancer genomic medicine using next-generation sequencers has been developing. However, the number of patients who could receive genomically matched therapy is limited because off-label use or patient-oriented compassionate use was not permitted under National Health Insurance in Japan. To improve patient drug accessibility, we initiated a biomarker-based basket-type clinical trial (NCCH1901) in October 2019 under patient-proposed healthcare services. We listed the drugs that had high medical needs but were not covered by National Healthcare Insurance. Then we included these drugs before patient proposal so that they could access off-label drugs soon after they had the results of CGP tests. All drugs were provided free of charge by pharmaceutical companies. The objective was to administer off-label drugs and to collect efficacy and safety data for these drugs. The primary endpoint was the response rate based on the best overall response for up to 16 weeks. As of January 31, 2022, we included 18 drug cohorts and 295 patients were treated in this study. The most common cancer was brain tumor, followed by carcinoma of endocrine organs and colorectal cancer. BRAF mutations and ERBB2 amplifications were the frequent genomic abnormalities to be enrolled. This study was one way to access off-label drugs, and contributed significantly to providing treatment opportunities for patients in Japan.
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Neoplasias , Relatório de Pesquisa , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Biomarcadores , JapãoRESUMO
BACKGROUND: Emerging evidence supports tumor tissue-based comprehensive genomic profiling (CGP) in metastatic colorectal cancer (mCRC). Data on liquid biopsy-based circulating tumor DNA (ctDNA) CGP are scarce and mainly retrospective. Prospective comparison between the two tests is not currently available. MATERIALS AND METHODS: The CAPRI 2-GOIM trial investigates efficacy and safety of ctDNA-driven, cetuximab-based sequence of three treatment lines in patients with RAS/BRAFV600E wild-type (WT) mCRC, as determined by the local laboratory. Before first-line therapy, CGP is carried out with FoundationOne (F1) CDx and F1 Liquid (F1L) CDx (324 genes) on tumor tissue DNA and plasma ctDNA, respectively. RESULTS: For 2/207 (0.96%) patients, no ctDNA was detected by F1L CDx. No patient displayed tumor fraction (TF) below 1%, whereas elevated ctDNA (TF ≥ 10%) was detected among 140/205 (68.3%) patients. One thousand and thirteen genomic variants were identified. F1L CDx found KRAS, NRAS, or BRAFV600E alterations in 19 patients, whose tumors were classified as RAS/BRAFV600E WT by the local laboratory. Both F1 CDx and F1L CDx were available for 164/205 (80%) patients. A concordance of 61.4% between the two tests was observed. The concordance increased to 72.7% for F1L CDx with TF ≥ 10%. Concordance for genes potentially involved in anti-epidermal growth factor receptor resistance was found in 137/164 (83%) patients, increasing to 91.5% for F1L CDx with TF ≥ 10%. A higher number of genomic alterations was detected by F1L CDx compared with F1 CDx, including six cases with KRAS and NRAS alterations. Overall, 109/205 (53.2%) patients displayed at least one actionable genomic alteration (I to IIIB), according to the European Society for Medical Oncology Scale for Clinical Actionability of Molecular Targets (ESCAT). CONCLUSION: Baseline liquid biopsy-based CGP is feasible, has high concordance with tumor tissue-based CGP, could better recapitulate tumor heterogeneity, and is clinically informative by identifying additional actionable genomic alterations in approximately half of RAS/BRAFV600E WT mCRC patients.
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OBJECTIVES: To comprehensively identify and map an exhaustive list of value criteria for the assessment of next-generation sequencing/comprehensive genomic profiling (NGS/CGP), to be used as an aid in decision making. METHODS: We conducted a systematic review to identify existing value frameworks (VFs) applicable to any type of healthcare technology. VFs and criteria were mapped to a previously published Latin American (LA) VF to harmonize definitions and identify additional criteria and or subcriteria. Based on this analysis, we extracted a comprehensive, evidence-based list of criteria and subcriteria to be considered in the design of a NGS/CGP VF. RESULTS: A total of 42 additional VFs were compared with the LA VF, 88% were developed in high-income countries, 30% targeted genomic testing, and 16% specifically targeted oncology. A total of 242 criteria and subcriteria were extracted; 227 (94%) were fully/partially included in the LA VF; and 15 (6%) were new. Clinical benefit and economic aspects were the most common criteria. VFs oriented to genomic testing showed significant overlap with other VFs. Considering all criteria and subcriteria, a total of 18 criteria and 36 individual subcriteria were identified. CONCLUSIONS: Our study provides an evidence-based set of criteria and subcriteria for healthcare decision making useful for NGS/CGP as well as other health technologies. The resulting list can be beneficial to inform decision making and will serve as a foundation to co-create a multistakeholder NGS/CGP VF that is aligned with the needs and values of health systems and could help to improve patient access to high-value technologies.
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Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Sequenciamento de Nucleotídeos em Larga Escala/economia , Análise Custo-Benefício , Testes Genéticos/economia , Testes Genéticos/normas , Testes Genéticos/métodos , Tomada de DecisõesRESUMO
INTRODUCTION: ADP-stimulated elevation of cytosolic Ca2+ is an important effector mechanism for platelet activation. The rapidly elevating cytosolic Ca2+ is also transported to mitochondrial matrix via Mitochondrial Ca2+ Uniporter (MCU) and extruded via Na+/Ca2+/Li+ Exchanger (NCLX). However, the exact contribution of MCU and NCLX in ADP-mediated platelet responses remains incompletely understood. METHODS AND RESULTS: The present study aimed to elucidate the role of mitochondrial Ca2+ transport in ADP-stimulated platelet responses by inhibition of MCU and NCLX with mitoxantrone (MTX) and CGP37157 (CGP), respectively. As these inhibitory strategies are reported to cause distinct effects on matrix Ca2+ concentration, we hypothesized to observe opposite impact of MTX and CGP on ADP-induced platelet responses. Platelet aggregation profiling was performed by microplate-based spectrophotometery while p-selectin externalization and integrin αIIbß3 activation were analyzed by fluorescent immunolabeling using flow cytometery. Our results confirmed the expression of both MCU and NCLX mRNAs with relatively low abundance of NCLX in human platelets. In line with our hypothesis, MTX caused a dose-dependent inhibition of ADP-induced platelet aggregation without displaying any cytotoxicity. Likewise, ADP-induced p-selectin externalization and integrin αIIbß3 activation was also significantly attenuated in MTX-treated platelets. Concordantly, inhibition of NCLX with CGP yielded an accelerated ADP-stimulated platelet aggregation which was associated with an elevation of p-selectin surface expression and αIIbß3 activation. CONCLUSION: Together, these findings uncover a vital and hitherto poorly characterized role of mitochondrial Ca2+ transporters in ADP-induced platelet activation.
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Cálcio , Selectina-P , Humanos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas , Plaquetas , Proteínas de Transporte da Membrana Mitocondrial , MitoxantronaRESUMO
Molecular profiles of thymomas and recurrent thymomas are far from being defined. Herein, we report an analysis of a comprehensive genetic profile (CGP) in a highly selected cohort of recurrent thymomas. Among a cohort of 426 thymomas, the tissue was available in 23 recurrent tumors for matching the biomolecular results obtained from primary and relapse samples. A control group composed of non-recurrent thymoma patients was selected through a propensity score match analysis. CGP was performed using the NGS Tru-SightOncology assay to evaluate TMB, MSI, and molecular alterations in 523 genes. CGP does not differ when comparing initial tumor with tumor relapse. A significantly higher frequency of cell cycle control genes alterations (100.0% vs. 57.1%, p = 0.022) is detected in patients with early recurrence (<32 months) compared to late recurrent cases. The CGPs were similar in recurrent thymomas and non-recurrent thymomas. Finally, based on NGS results, an off-label treatment or clinical trial could be potentially proposed in >50% of cases (oncogenic Tier-IIC variants). In conclusion, CGPs do not substantially differ between initial tumor vs. tumor recurrence and recurrent thymomas vs. non-recurrent thymomas. Cell cycle control gene alterations are associated with an early recurrence after thymectomy. Multiple target therapies are potentially available by performing a comprehensive CGP, suggesting that a precision medicine approach on these patients could be further explored.
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Mutação , Recidiva Local de Neoplasia , Timoma , Neoplasias do Timo , Humanos , Timoma/genética , Timoma/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias do Timo/genética , Neoplasias do Timo/patologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Idoso , Adulto , Genômica/métodos , Terapia de Alvo Molecular , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Biomarcadores Tumorais/genéticaRESUMO
The blood cancer field has played a pioneering role in advancing precision medicine, with milestones such as development of ABL1 inhibitors for chronic myeloid leukemia. The significance of gene mutation information in AML treatment has increased, evident in classifications and guidelines from organizations such as WHO and ELN. This article examines the anticipated roles of cancer genome panels (CGPs) in AML treatment from three perspectives: diagnosis, risk stratification, and treatment selection. Use of CGPs enables more accurate diagnosis and risk stratification. In treatment selection, CGPs not only complements but also substitutes existing companion diagnostics, and is expected to be a crucial information source for future drug adoption and investigation of tumor-agnostic therapies. However, various challenges remain to be addressed, including the purpose and timing of CGPs, the time required for the tests, and how to utilize expert panels.
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Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/diagnóstico , Mutação , Genoma Humano , Medicina de PrecisãoRESUMO
The EU In-Vitro Diagnostic Device Regulation (IVDR) aims for transparent risk-and purpose-based validation of diagnostic devices, traceability of results to uniquely identified devices, and post-market surveillance. The IVDR regulates design, manufacture and putting into use of devices, but not medical services using these devices. In the absence of suitable commercial devices, the laboratory can resort to laboratory-developed tests (LDT) for in-house use. Documentary obligations (IVDR Art 5.5), the performance and safety specifications of ANNEX I, and development and manufacture under an ISO 15189-equivalent quality system apply. LDTs serve specific clinical needs, often for low volume niche applications, or correspond to the translational phase of new tests and treatments, often extremely relevant for patient care. As some commercial tests may disappear with the IVDR roll-out, many will require urgent LDT replacement. The workload will also depend on which modifications to commercial tests turns them into an LDT, and on how national legislators and competent authorities (CA) will handle new competences and responsibilities. We discuss appropriate interpretation of ISO 15189 to cover IVDR requirements. Selected cases illustrate LDT implementation covering medical needs with commensurate management of risk emanating from intended use and/or design of devices. Unintended collateral damage of the IVDR comprises loss of non-profitable niche applications, increases of costs and wasted resources, and migration of innovative research to more cost-efficient environments. Taking into account local specifics, the legislative framework should reduce the burden on and associated opportunity costs for the health care system, by making diligent use of existing frameworks.
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Serviços de Laboratório Clínico , Kit de Reagentes para Diagnóstico , Humanos , Kit de Reagentes para Diagnóstico/normas , União Europeia , Serviços de Laboratório Clínico/legislação & jurisprudênciaRESUMO
Two diazotrophic cyanobacteria (Anabaena cylindrica PCC 7122 and Nostoc sp. PCC 7120) were cultivated to produce cyanophycin, a nitrogen reserve compound, under nitrogen fixing conditions. In preliminary continuous experiments, Nostoc sp. was shown to be more efficient, accumulating a higher amount of cyanophycin and showing a greater capability to fix atmospheric nitrogen in the biomass (67 mgN d-1 of fixed nitrogen per liter of culture). The operating conditions were then optimized to maximize the cyanophycin productivity: the effect of incident light intensity, residence time and nitrogen availability were investigated. Nitrogen availability and/or pH played a major role with respect to biomass production, whereas phosphorus limitation was the main variable to maximize cyanophycin accumulation. In this way, it was possible to achieve a stable and continuous production of cyanophycin (CGP) under diazotrophic conditions, obtaining a maximum cyanophycin productivity of 15 mgCGP L-1 d-1. KEY POINTS: ⢠Diazotrophic cyanobacteria produce stable amount of cyanophycin in continuous PBR. ⢠Nostoc sp. proved to be more efficient in producing cyanophycin than Anabaena sp. ⢠P deprivation is the major variable to increase cyanophycin productivity in continuous.
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Anabaena , Nostoc , Proteínas de Bactérias , NitrogênioRESUMO
Insulin-like growth factor-1 (IGF-1) function declines with age and is associated with brain ageing and the progression of age-related neurological conditions. The reversible binding of IGF-1 to IGF binding protein (IGFBP)-3 regulates the amount of bioavailable, functional IGF-1 in circulation. Cyclic glycine-proline (cGP), a metabolite from the binding site of IGF-1, retains its affinity for IGFBP-3 and competes against IGF-1 for IGFBP-3 binding. Thus, cGP and IGFBP-3 collectively regulate the bioavailability of IGF-1. The molar ratio of cGP/IGF-1 represents the amount of bioavailable and functional IGF-1 in circulation. The cGP/IGF-1 molar ratio is low in patients with age-related conditions, including hypertension, stroke, and neurological disorders with cognitive impairment. Stroke patients with a higher cGP/IGF-1 molar ratio have more favourable clinical outcomes. The elderly with more cGP have better memory retention. An increase in the cGP/IGF-1 molar ratio with age is associated with normal cognition, whereas a decrease in this ratio with age is associated with dementia in Parkinson disease. In addition, cGP administration reduces systolic blood pressure, improves memory, and aids in stroke recovery. These clinical and experimental observations demonstrate the role of cGP in regulating IGF-1 function and its potential clinical applications in age-related brain diseases as a plasma biomarker for-and an intervention to improve-IGF-1 function.
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Doenças do Sistema Nervoso , Doença de Parkinson , Acidente Vascular Cerebral , Humanos , Idoso , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina , Fator de Crescimento Insulin-Like I/metabolismo , Relevância Clínica , Acidente Vascular Cerebral/tratamento farmacológico , Encéfalo/metabolismo , EnvelhecimentoRESUMO
BACKGROUND: Determining the tissue of origin (TOO) is essential for managing cancer of unknown primary (CUP). In this study, we evaluated the concordance between genome profiling and DNA methylation analysis in determining TOO for lung-specific CUP and assessed their performance by comparing the clinical responses and survival outcomes of patients predicted with multiple primary or with metastatic cancer. METHODS: We started by retrospectively screening for CUP patients who presented with both intra- and extrathoracic tumors. Tumor samples from included patients were analyzed with targeted sequencing with a 520-gene panel and targeted bisulfite sequencing. TOO inferences were made in parallel via an algorithm using genome profiles and time interval between tumors and via machine learning-based classification of DNA methylation profiles. RESULTS: Four hundred patients were screened retrospectively. Excluding patients definitively diagnosed with conventional diagnostic work-up or without available samples, 16 CUP patients were included. Both molecular approaches alone enabled inference of clonality for all analyzed patients. Genome profile enabled TOO inference for 43.8% (7/16) patients, and the percentage rose to 68.8% (11/16) after considering inter-tumor time lag. On the other hand, DNA methylation analysis was conclusive for TOO prediction for 100% (14/14) patients with available samples. The two approaches gave 100% (9/9) concordant inferences regarding clonality and TOO identity. Moreover, patients predicted with metastatic disease showed significantly shorter overall survival than those with multiple primary tumors. CONCLUSIONS: Genome and DNA methylation profiling have shown promise as individual analysis for TOO identification. This study demonstrated the feasibility of incorporating the two methods and proposes an integrative scheme to facilitate diagnosing and treating lung-specific CUPs.
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Neoplasias Primárias Desconhecidas , Metilação de DNA/genética , Perfilação da Expressão Gênica/métodos , Humanos , Pulmão/patologia , Neoplasias Primárias Desconhecidas/genética , Neoplasias Primárias Desconhecidas/patologia , Estudos RetrospectivosRESUMO
For years, the AT2R-selective ligand CGP42112 has been erroneously characterized as a partial agonist, partly due to its ability to also interact with the AT1R at high concentrations. As late as 2009, it was still being characterized as an antagonist as well. In this perspective/opinion piece, we try to resolve the ambiguity that surrounds the efficacy of this compound by extensively reviewing the literature, tracing its beginnings to 1989, showing that CGP42112 has never been convincingly shown to be a partial agonist or an antagonist at the AT2R. While CGP42112 is now routinely characterized as an AT2R agonist, regrettably, there is a paucity of studies that can validate its efficacy as a full agonist at the AT2R, leaving the door open for continuing speculation regarding the extent of its efficacy. Hopefully, the information presented in this perspective/opinion piece will firmly establish CGP42112 as a full agonist at the AT2R such that it can once again be used as a tool to study the AT2R.
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Receptor Tipo 2 de Angiotensina , Sistema Renina-Angiotensina , Receptor Tipo 2 de Angiotensina/agonistas , Oligopeptídeos , LigantesRESUMO
Severe plastic deformation (SPD) is a widely used technique to obtain superior material properties specially mechanical properties. Constrained groove pressing (CGP) is found to be the most attractive SPD technique for the deformation of sheets and plates. However, this technique results in microstructural inhomogeneity during processing. The microstructural inhomogeneity can be alleviated by employing a thermal cycle, which assists in controlled recovery and recrystallisation. The current work focuses on, the microstructure evolution of one pass as-deform CGP sample followed by a short heat-treated (SHT). A correlative imaging technique of transmission Kikuchi diffraction (TKD) and transmission electron microscopy (TEM) showed the presence of dislocation cell structure in an as-deformed condition. The short heat treatment resulted in the transformation of the dislocation cell wall to high-angle boundaries, with a further increase in heat-treatment time resulting in grain growth.
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A majority of patients with metastatic colorectal cancer (mCRC) experience recurrence post curative-intent surgery. The addition of adjuvant chemotherapy has shown to provide limited survival benefits when applied to all patients. Therefore, a biomarker to assess molecular residual disease (MRD) accurately and guide treatment selection is highly desirable for high-risk patients. This feasibility study evaluated the prognostic value of a tissue comprehensive genomic profiling (CGP)-informed, personalized circulating tumor DNA (ctDNA) assay (FoundationOne®Tracker) (Foundation Medicine, Inc., Cambridge, MA, USA) by correlating MRD status with clinical outcomes. ctDNA analysis was performed retrospectively on plasma samples from 69 patients with resected mCRC obtained at the MRD and the follow-up time point. Tissue CGP identified potentially actionable alterations in 54% (37/69) of patients. MRD-positivity was significantly associated with lower disease-free survival (DFS) (HR: 4.97, 95% CI: 2.67−9.24, p < 0.0001) and overall survival (OS) (HR: 27.05, 95% CI: 3.60−203.46, p < 0.0001). Similarly, ctDNA positive status at the follow-up time point correlated with a marked reduction in DFS (HR: 8.78, 95% CI: 3.59−21.49, p < 0.0001) and OS (HR: 20.06, 95% CI: 2.51−160.25, p < 0.0001). The overall sensitivity and specificity at the follow-up time point were 69% and 100%, respectively. Our results indicate that MRD detection using the tissue CGP-informed ctDNA assay is prognostic of survival outcomes in patients with resected mCRC. The concurrent MRD detection and identification of actionable alterations has the potential to guide perioperative clinical decision-making.
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DNA Tumoral Circulante , Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Biomarcadores Tumorais/genética , DNA Tumoral Circulante/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/cirurgia , Progressão da Doença , Genômica , Humanos , Neoplasia Residual/diagnóstico , Neoplasia Residual/genética , Neoplasia Residual/patologia , Estudos RetrospectivosRESUMO
Based on the approvals of crizotinib and entrectinib by the Food and Drug Administration for the treatment of ROS1 positive nonsmall cell lung cancer (NSCLC), we sought to examine the mutational profile of a variety of solid tumors (excluding sarcomas) with ROS1 fusions that underwent comprehensive genomic profiling. A review of our database was performed to extract all nonsarcoma patients with ROS1 fusions that were discovered by the hybrid capture-based DNA only sequencing assays. We examined the coalterations representing potentially targetable biomarkers, resistance alterations and other alterations in these cases. In addition, we examined the histologic characteristics and protein expression with immunohistochemistry (IHC). From a series of clinically advanced nonsarcoma solid tumors, 356 unique cases with ROS1 fusions included 275 (77.2%) NSCLC and 81 (22.8%) non-NSCLC. Ten novel ROS1 fusions were discovered. Importantly, the NSCLC ROS1 fusionpos tumors had a higher PD-L1 IHC expression positivity when compared to the NSCLC ROS1 fusionneg population (P = .012, Chi-squared). The frequency of known and likely anti-ROS1 targeted therapy resistance genomic alterations in NSCLC was 7.3% (20/275) and in non-NSCLC was 4.9% (4/81). Overall, the coalteration profile of ROS1 fusionpos NSCLC and non-NSCLC was similar with only three genes altered significantly more frequently in non-NSCLC vs NSCLC: TERT, PTEN, APC. In our study, we characterized a large cohort of ROS1 fusionpos NSCLC and non-NSCLC solid tumors and discovered 10 novel ROS1 fusions.
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Biomarcadores Tumorais/genética , Neoplasias Pulmonares/genética , Fusão Oncogênica/genética , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Idoso , Antígeno B7-H1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Estudos de Coortes , Bases de Dados Genéticas , Feminino , Genômica , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/metabolismo , Estudos RetrospectivosRESUMO
Adaptive responses to stress are critical to enhance physical and mental well-being, but excessive or prolonged stress may cause inadaptability and increase the risks of psychiatric disorders, such as depression. GABABR signaling is fundamental to brain function and has been identified in neuropsychiatric disorders. KCTD12 is a critical auxiliary subunit in GABABR signaling, but its role in mental disorders, such as depression is unclear. In the present study, we used a well-validated mice model, chronic social defeat stress (CSDS) to investigate behavioral responses to stress and explore the role of Kctd12 in stress response, as well as the relevant mechanisms. We found that CSDS increased the expression of Kctd12 in the dentate gyrus (DG), a subregion of hippocampus. Overexpression of Kctd12 in DG induced higher responsiveness to acute stress and increased vulnerability to social stress in mice, whereas knock-down of Kctd12 in DG prevented the social avoidance. Furthermore, an increased expression of GABAB receptor 2 (GB2) in the DG of CSDS-treated mice was observed, and CGP35348, an antagonist of GABABR, improved the stress-induced behavior responses along with suppressing the excess expression of Kctd12. In addition, Kctd12 regulated the excitability of granule cell in DG, and the stimulation of neuronal activity by silencing Kctd12 contributed to the antidepressant-like effect of fluoxetine. These findings identify that the Kctd12 in DG works as a critical mediator of stress responses, providing a promising therapeutic target in stress-related psychiatric disorders, including depression.
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Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Comportamento Animal , Derrota Social , Estresse Psicológico/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Antidepressivos/farmacologia , Giro Denteado/metabolismo , Depressão/metabolismo , Modelos Animais de Doenças , Fluoxetina/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Subunidades Proteicas , RNA Interferente Pequeno/genética , Receptores de GABA-BRESUMO
We have previously shown that cannabinoid CB1 and CB2 receptor antagonists, AM251 and AM630, respectively, modulate cardiostimulatory effects of isoprenaline in atria of Wistar rats. The aim of the present study was to examine whether such modulatory effects can also be observed (a) in the human atrium and (b) in spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto rats (WKY). Inotropic effects of isoprenaline and/or CGP12177 (that activate the high- and low-affinity site of ß1 -adrenoceptors, respectively) were examined in paced human atrial trabeculae and rat left atria; chronotropic effects were studied in spontaneously beating right rat atria. AM251 modified cardiostimulatory effects more strongly than AM630. Therefore, AM251 (1 µM) enhanced the chronotropic effect of isoprenaline in WKY and SHR as well as inotropic action of isoprenaline in WKY and in human atria. It also increased the inotropic influence of CGP12177 in SHR. AM630 (1 µM) decreased the inotropic effect of isoprenaline and CGP12177 in WKY, but enhanced the isoprenaline-induced inotropic effect in SHR and human atria. Furthermore, AM251 (0.1 and 3 µM) and AM630 (0.1 µM) reduced the inotropic action of isoprenaline in human atria. In conclusion, cannabinoid receptor antagonists have potentially harmful and beneficial effects through their amplificatory effects on ß-adrenoceptor-mediated positive chronotropic and inotropic actions, respectively.
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IsoproterenolRESUMO
In excitable cells, mitochondria play a key role in the regulation of the cytosolic Ca2+ levels. A dysregulation of the mitochondrial Ca2+ buffering machinery derives in serious pathologies, where neurodegenerative diseases highlight. Since the mitochondrial Na+/Ca2+ exchanger (NCLX) is the principal efflux pathway of Ca2+ to the cytosol, drugs capable of blocking NCLX have been proposed to act as neuroprotectants in neuronal damage scenarios exacerbated by Ca2+ overload. In our search of optimized NCLX blockers with augmented drug-likeness, we herein describe the synthesis and pharmacological characterization of new benzothiazepines analogues to the first-in-class NCLX blocker CGP37157 and its further derivative ITH12575, synthesized by our research group. As a result, we found two new compounds with an increased neuroprotective activity, neuronal Ca2+ regulatory activity and improved drug-likeness and pharmacokinetic properties, such as clog p or brain permeability, measured by PAMPA experiments.
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Doenças Neurodegenerativas/tratamento farmacológico , Neurônios/efeitos dos fármacos , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores , Acidente Vascular Cerebral/tratamento farmacológico , Tiazepinas , Animais , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/síntese química , Bloqueadores dos Canais de Cálcio/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Mitocôndrias , Neurônios/patologia , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/farmacologia , Ratos , Tiazepinas/síntese química , Tiazepinas/farmacologiaRESUMO
Shrm4 is a protein that is exclusively expressed in polarized tissues. The physiological function of Shrm4 in the brain was required to be elucidated. Thus, we aimed to explore how the Shrm4-mediated gamma-aminobutyric acid (GABA) pathway affected neural stem cells (NSCs). At first, the Nestin expression in cultured NSCs was identified. After determination of the interaction of Shrm4 and GABAB1, a series of in vitro experiment were performed to detect cell proliferation, the ability of cell colony formation, degree that NSCs differentiated into neurons, the apoptosis rate, and cell cycle. The levels of Shrm4, GABAB1, Bcl-2-associated protein x (Bax), B cell lymphoma 2 (Bcl-2), cleaved Caspase-3, microtubule-associated protein 2 (MAP-2) as well as suppressor of cytokine signaling 2 (SOCS2) were detected to further assess the role of Shrm4 and GABA pathway in NSCs. Initially, we found that Shrm4 could bind to GABAB1, and overexpression of Shrm4 or activation of GABAB1 increased the number of positive cells, and promoted cell viability, colony formation rate and differentiation of NSCs. After overexpression of Shrm4 or activation of GABAB1, cells in the G1 phase were decreased, while those in the S phase were increased with an inhibited cell apoptosis rate in the NSCs. Besides, the overexpression of Shrm4 or activation of GABAB1 upregulated the levels of Shrm4, GABAB1, Bcl-2, MAP-2 and SOCS2, while downregulated Bax and cleaved Caspase-3 in NSCs. Overall, overexpression of Shrm4 activated GABAB1 to stimulate the proliferation and differentiation of NSCs. Thus, Shrm4 might be considered as a novel target for promoting the proliferation and differentiation of NSCs.