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1.
Sensors (Basel) ; 23(7)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37050691

RESUMO

Wireless acoustic sensor networks (WASNs) and intelligent microsystems are crucial components of the Internet of Things (IoT) ecosystem. In various IoT applications, small, lightweight, and low-power microsystems are essential to enable autonomous edge computing and networked cooperative work. This study presents an innovative intelligent microsystem with wireless networking capabilities, sound sensing, and sound event recognition. The microsystem is designed with optimized sensing, energy supply, processing, and transceiver modules to achieve small size and low power consumption. Additionally, a low-computational sound event recognition algorithm based on a Convolutional Neural Network has been designed and integrated into the microsystem. Multiple microsystems are connected using low-power Bluetooth Mesh wireless networking technology to form a meshed WASN, which is easily accessible, flexible to expand, and straightforward to manage with smartphones. The microsystem is 7.36 cm3 in size and weighs 8 g without housing. The microsystem can accurately recognize sound events in both trained and untrained data tests, achieving an average accuracy of over 92.50% for alarm sounds above 70 dB and water flow sounds above 55 dB. The microsystems can communicate wirelessly with a direct range of 5 m. It can be applied in the field of home IoT and border security.

2.
Sensors (Basel) ; 22(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36559962

RESUMO

Microsystems play an important role in the Internet of Things (IoT). In many unattended IoT applications, microsystems with small size, lightweight, and long life are urgently needed to achieve covert, large-scale, and long-term distribution for target detection and recognition. This paper presents for the first time a low-power, long-life microsystem that integrates self-power supply, event wake-up, continuous vibration sensing, and target recognition. The microsystem is mainly used for unattended long-term target perception and recognition. A composite energy source of solar energy and battery is designed to achieve self-powering. The microsystem's sensing module, circuit module, signal processing module, and transceiver module are optimized to further realize the small size and low-power consumption. A low-computational recognition algorithm based on support vector machine learning is designed and ported into the microsystem. Taking the pedestrian, wheeled vehicle, and tracked vehicle as targets, the proposed microsystem of 15 cm3 and 35 g successfully realizes target recognitions both indoors and outdoors with an accuracy rate of over 84% and 65%, respectively. Self-powering of the microsystem is up to 22.7 mW under the midday sunlight, and 11 min self-powering can maintain 24 h operation of the microsystem in sleep mode.


Assuntos
Energia Solar , Vibração , Luz Solar , Fontes de Energia Elétrica , Algoritmos
3.
BMC Bioinformatics ; 21(Suppl 9): 218, 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33272232

RESUMO

BACKGROUND: Lung cancer is the number one cancer killer in the world with more than 142,670 deaths estimated in the United States alone in the year 2019. Consequently, there is an overreaching need to identify the key biomarkers for lung cancer. The aim of this study is to computationally identify biomarker genes for lung cancer that can aid in its diagnosis and treatment. The gene expression profiles of two different types of studies, namely non-treatment and treatment, are considered for discovering biomarker genes. In non-treatment studies healthy samples are control and cancer samples are cases. Whereas, in treatment studies, controls are cancer cell lines without treatment and cases are cancer cell lines with treatment. RESULTS: The Differentially Expressed Genes (DEGs) for lung cancer were isolated from Gene Expression Omnibus (GEO) database using R software tool GEO2R. A total of 407 DEGs (254 upregulated and 153 downregulated) from non-treatment studies and 547 DEGs (133 upregulated and 414 downregulated) from treatment studies were isolated. Two Cytoscape apps, namely, CytoHubba and MCODE, were used for identifying biomarker genes from functional networks developed using DEG genes. This study discovered two distinct sets of biomarker genes - one from non-treatment studies and the other from treatment studies, each set containing 16 genes. Survival analysis results show that most non-treatment biomarker genes have prognostic capability by indicating low-expression groups have higher chance of survival compare to high-expression groups. Whereas, most treatment biomarkers have prognostic capability by indicating high-expression groups have higher chance of survival compare to low-expression groups. CONCLUSION: A computational framework is developed to identify biomarker genes for lung cancer using gene expression profiles. Two different types of studies - non-treatment and treatment - are considered for experiment. Most of the biomarker genes from non-treatment studies are part of mitosis and play vital role in DNA repair and cell-cycle regulation. Whereas, most of the biomarker genes from treatment studies are associated to ubiquitination and cellular response to stress. This study discovered a list of biomarkers, which would help experimental scientists to design a lab experiment for further exploration of detail dynamics of lung cancer development.


Assuntos
Biomarcadores Tumorais/genética , Biologia Computacional/métodos , Neoplasias Pulmonares/genética , Biomarcadores Tumorais/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Redes Reguladoras de Genes , Humanos , Prognóstico , Mapas de Interação de Proteínas/genética , Transdução de Sinais/genética , Análise de Sobrevida
4.
Oncologist ; 25(8): e1158-e1169, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32452601

RESUMO

BACKGROUND: Poly(ADP-ribose) polymerase inhibitors (PARPis) are U.S. Food and Drug Administration (FDA) approved for treatment of BRCA-mutated metastatic breast cancer. Furthermore, the BROCADE studies demonstrated benefit of adding an oral PARPi, veliparib, to carboplatin and paclitaxel in patients with metastatic breast cancer harboring BRCA mutation. Given multiple possible dosing schedules and the potential benefit of this regimen for patients with defective DNA repair beyond BRCA, we sought to find the recommended phase II dose (RP2D) and schedule of veliparib in combination with carboplatin in patients with advanced breast cancer, either triple-negative (TNBC) or hormone receptor (HR)-positive, human epidermal growth receptor 2 (HER2) negative with defective Fanconi anemia (FA) DNA-repair pathway based on FA triple staining immunofluorescence assay. MATERIALS AND METHODS: Patients received escalating doses of veliparib on a 7-, 14-, or 21-day schedule with carboplatin every 3 weeks. Patients underwent [18]fluoro-3'-deoxythymidine (18 FLT) positron emission tomography (PET) imaging. RESULTS: Forty-four patients (39 TNBC, 5 HR positive/HER2 negative with a defective FA pathway) received a median of 5 cycles (range 1-36). Observed dose-limiting toxicities were grade (G) 4 thrombocytopenia (n = 4), G4 neutropenia (n = 1), and G3 akathisia (n = 1). Common grade 3-4 toxicities included thrombocytopenia, lymphopenia, neutropenia, anemia, and fatigue. Of the 43 patients evaluable for response, 18.6% achieved partial response and 48.8% had stable disease. Median progression-free survival was 18.3 weeks. RP2D of veliparib was established at 250 mg twice daily on days 1-21 along with carboplatin at area under the curve 5. Patients with partial response had a significant drop in maximum standard uptake value (SUVmax ) of target lesions between baseline and early in cycle 1 based on 18 FLT-PET (day 7-21; ptrend = .006). CONCLUSION: The combination of continuous dosing of veliparib and every-3-week carboplatin demonstrated activity and an acceptable toxicity profile. Decrease in SUVmax on 18 FLT-PET scan during the first cycle of this therapy can identify patients who are likely to have a response. IMPLICATIONS FOR PRACTICE: The BROCADE studies suggest that breast cancer patients with BRCA mutation benefit from addition of veliparib to carboplatin plus paclitaxel. This study demonstrates that a higher dose of veliparib is tolerable and active in combination with carboplatin alone. With growing interest in imaging-based early response assessment, the authors demonstrate that decrease in [18]fluoro-3'-deoxythymidine positron emission tomography (FLT-PET) SUVmax during cycle 1 of therapy is associated with response. Collectively, this study established a safety profile of veliparib and carboplatin in advanced breast cancer while also providing additional data on the potential for FLT-PET imaging modality in monitoring therapy response.


Assuntos
Neoplasias da Mama , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Benzimidazóis , Biomarcadores , Neoplasias da Mama/tratamento farmacológico , Carboplatina/uso terapêutico , Feminino , Humanos , Tomografia por Emissão de Pósitrons
5.
BMC Cancer ; 20(1): 738, 2020 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-32770960

RESUMO

BACKGROUND: Lung cancer is the number one cancer killer worldwide. A major drawback in the lung cancer treatment field is the lack of realistic mouse models that replicate the complexity of human malignancy and immune contexture within the tumor microenvironment. Such models are urgently needed. Mutations of the tumor protein p53 are among the most common alterations in human lung cancers. METHODS: Previously, we developed a line of lung cancer mouse model where mutant human TP53-273H is expressed in a lung specific manner in FVB/N background. To investigate whether the human TP53 mutant has a similar oncogenic potential when it is expressed in another strain of mouse, we crossed the FVB/N-SPC-TP53-273H mice to A/J strain and created A/J-SPC-TP53-273H transgenic mice. We then compared lung tumor formation between A/J-SPC-TP53-273H and FVB/N-SPC-TP53-273H. RESULTS: We found the TP53-273H mutant gene has a similar oncogenic potential in lung tumor formation in both mice strains, although A/J strain mice have been found to be a highly susceptible strain in terms of carcinogen-induced lung cancer. Both transgenic lines survived more than 18 months and developed age related lung adenocarcinomas. With micro CT imaging, we found the FVB-SPC-TP53-273H mice survived more than 8 weeks after initial detection of lung cancer, providing a sufficient window for evaluating new anti-cancer agents. CONCLUSIONS: Oncogenic potential of the most common genetic mutation, TP53-273H, in human lung cancer is unique when it is expressed in different strains of mice. Our mouse models are useful tools for testing novel immune checkpoint inhibitors or other therapeutic strategies in the treatment of lung cancer.


Assuntos
Modelos Animais de Doenças , Genes p53 , Neoplasias Pulmonares/genética , Camundongos Transgênicos , Mutação , Fatores Etários , Animais , Cruzamentos Genéticos , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos A , Microambiente Tumoral
6.
Int J Cancer ; 145(9): 2418-2426, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30873587

RESUMO

TP53 and K-ras mutations are two of the major genetic alterations in human nonsmall cell lung cancers. The association between these two genes during lung tumorigenesis is unknown. We evaluated the potential of two common Type I (273H, contact) and Type II (175H, conformational) TP53 mutations to induce lung tumors in transgenic mice, as well as K-ras status, and other driver mutations in these tumors. Among 516 (138 nontransgenic, 207 SPC-TP53-273H, 171 SPC-TP53-175H) mice analyzed, 91 tumors, all adenocarcinomas, were observed. Type II mutants developed tumors more frequently (as compared to nontransgenics, p = 0.0003; and Type I, p = 0.010), and had an earlier tumor onset compared to Type I (p = 0.012). K-ras mutations occurred in 21 of 50 (42%) of murine lung tumors sequenced. For both the nontransgenic and the SPC-TP53-273H transgenics, tumor K-ras codon 12-13 mutations occurred after 13 months with a peak incidence at 16-18 months. However, for the SPC-TP53-175H transgenics, K-ras codon 12-13 mutations were observed as early as 6 months, with a peak incidence between the ages of 10-12 months. Codons 12-13 transversion mutations were the predominant changes in the SPC-TP53-175H transgenics, whereas codon 61 transition mutations were more common in the SPC-TP53-273H transgenics. The observation of accelerated tumor onset, early appearance and high frequency of K-ras codon 12-13 mutations in the Type II TP53-175H mice suggests an enhanced oncogenic function of conformational TP53 mutations, and gains in early genetic instability for tumors containing these mutations compared to contact mutations.


Assuntos
Adenocarcinoma de Pulmão/patologia , Neoplasias Pulmonares/patologia , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína Supressora de Tumor p53/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Idade de Início , Animais , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Conformação Proteica , Análise de Sequência de DNA , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/metabolismo
7.
Proc Natl Acad Sci U S A ; 111(11): 4179-84, 2014 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-24586049

RESUMO

Neuroblastoma rat sarcoma (RAS) viral oncogene homolog (NRAS), a small GTPase, is one of the most thoroughly studied oncogenes that controls cell growth, differentiation, and survival by facilitating signal transduction. Here, we identify four novel naturally occurring NRAS isoforms (isoforms 2-5) in addition to the canonical isoform (isoform 1). Expression analyses performed on a panel of several different human malignancies and matching normal tissue revealed distinct isoform expression patterns. Two of the novel isoforms were found in the nucleus and cytoplasm, whereas the others were exclusively cytoplasmic. The isoforms varied in their binding affinities to known downstream targets and differentially regulated the RAS signaling pathway. Strikingly, forced expression of isoform 5, which encodes only a 20-aa peptide, led to increased cell proliferation and to transformation by activation of known NRAS targets. These discoveries open new avenues in the study of NRAS.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Transformação Celular Neoplásica/genética , GTP Fosfo-Hidrolases/genética , Regulação Neoplásica da Expressão Gênica/genética , Proteínas de Membrana/genética , Isoformas de Proteínas/genética , Transdução de Sinais/genética , Animais , Sequência de Bases , Western Blotting , Células COS , Chlorocebus aethiops , Clonagem Molecular , Primers do DNA/genética , Humanos , Imunoprecipitação , Camundongos , Microscopia Confocal , Dados de Sequência Molecular , Células NIH 3T3 , Análise de Sequência de DNA , Estatísticas não Paramétricas
8.
Sensors (Basel) ; 17(6)2017 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-28587115

RESUMO

Magnetometers combined with inertial sensors are widely used for orientation estimation, and calibrations are necessary to achieve high accuracy. This paper presents a complete tri-axis magnetometer calibration algorithm with a gyro auxiliary. The magnetic distortions and sensor errors, including the misalignment error between the magnetometer and assembled platform, are compensated after calibration. With the gyro auxiliary, the magnetometer linear interpolation outputs are calculated, and the error parameters are evaluated under linear operations of magnetometer interpolation outputs. The simulation and experiment are performed to illustrate the efficiency of the algorithm. After calibration, the heading errors calculated by magnetometers are reduced to 0.5° (1σ). This calibration algorithm can also be applied to tri-axis accelerometers whose error model is similar to tri-axis magnetometers.

9.
Mol Cancer ; 15(1): 47, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27296891

RESUMO

BACKGROUND: Fusion proteins have unique oncogenic properties and their identification can be useful either as diagnostic or therapeutic targets. Next generation sequencing data have previously shown a fusion gene formed between Rad51C and ATXN7 genes in the MCF7 breast cancer cell line. However, the existence of this fusion gene in colorectal patient tumor tissues is largely still unknown. METHODS: We evaluated for the presence of Rad51C-ATXN7 fusion gene in colorectal tumors and cells by RT-PCR, PCR, Topo TA cloning, Real time PCR, immunoprecipitation and immunoblotting techniques. RESULTS: We identified two forms of fusion mRNAs between Rad51C and ATXN7 in the colorectal tumors, including a Variant 1 (fusion transcript between Rad51C exons 1-7 and ATXN7 exons 6-13), and a Variant 2 (between Rad51C exons 1-6 and ATXN7 exons 6-13). In silico analysis showed that the Variant 1 produces a truncated protein, whereas the Variant 2 was predicted to produce a fusion protein with molecular weight of 110 KDa. Immunoprecipitation and Western blot analysis further showed a 110 KDa protein in colorectal tumors. 5-Azacytidine treatment of LS-174 T cells caused a 3.51-fold increase in expression of the fusion gene (Variant 2) as compared to no treatment controls evaluated by real time PCR. CONCLUSION: In conclusion we found a fusion gene between DNA repair gene Rad51C and neuro-cerebral ataxia Ataxin-7 gene in colorectal tumors. The in-frame fusion transcript of Variant 2 results in a fusion protein with molecular weight of 110 KDa. In addition, we found that expression of fusion gene is associated with functional impairment of Fanconi Anemia (FA) DNA repair pathway in colorectal tumors. The expression of Rad51C-ATXN7 in tumors warrants further investigation, as it suggests the potential of the fusion gene in treatment and predictive value in colorectal cancers.


Assuntos
Ataxina-7/genética , Clonagem Molecular/métodos , Neoplasias Colorretais/genética , Proteínas de Ligação a DNA/genética , Proteínas de Fusão Oncogênica/genética , Ataxina-7/metabolismo , Azacitidina/farmacologia , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Simulação por Computador , Metilação de DNA/efeitos dos fármacos , Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Variação Genética , Humanos , Peso Molecular , Proteínas de Fusão Oncogênica/efeitos dos fármacos , Proteínas de Fusão Oncogênica/metabolismo
10.
Front Neurosci ; 17: 1177118, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37113143

RESUMO

Information in conventional digital computing platforms is encoded in the steady states of transistors and processed in a quasi-static way. Memristors are a class of emerging devices that naturally embody dynamics through their internal electrophyiscal processes, enabling nonconventional computing paradigms with enhanced capability and energy efficiency, such as reservoir computing. Here, we report on a dynamic memristor based on LiNbO3. The device has nonlinear I-V characteristics and exhibits short-term memory, suitable for application in reservoir computing. By time multiplexing, a single device can serve as a reservoir with rich dynamics which used to require a large number of interconnected nodes. The collective states of five memristors after the application of trains of pulses to the respective memristors are unique for each combination of pulse patterns, which is suitable for sequence data classification, as demonstrated in a 5 × 4 digit image recognition task. This work broadens the spectrum of memristive materials for neuromorphic computing.

11.
Nat Commun ; 14(1): 6134, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37783711

RESUMO

Artificial neural networks (ANNs) have gained considerable momentum in the past decade. Although at first the main task of the ANN paradigm was to tune the connection weights in fixed-architecture networks, there has recently been growing interest in evolving network architectures toward the goal of creating artificial general intelligence. Lagging behind this trend, current ANN hardware struggles for a balance between flexibility and efficiency but cannot achieve both. Here, we report on a novel approach for the on-demand generation of complex networks within a single memristor where multiple virtual nodes are created by time multiplexing and the non-trivial topological features, such as small-worldness, are generated by exploiting device dynamics with intrinsic cycle-to-cycle variability. When used for reservoir computing, memristive complex networks can achieve a noticeable increase in memory capacity a and respectable performance boost compared to conventional reservoirs trivially implemented as fully connected networks. This work expands the functionality of memristors for ANN computing.

12.
Nanoscale ; 14(14): 5537-5544, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35343557

RESUMO

Exciton-exciton annihilation (EEA), as typical nonradiative recombination, plays an unpopular role in semiconductors. The nonradiative process significantly reduces the quantum yield of photoluminescence, which substantially inhibits the maximum efficiency of optoelectronic devices. Recently, laser irradiation, introducing defects and applying strain have become effective means to restrain EEA in two-dimensional (2D) transition metal dichalcogenides (TMDCs). However, these methods destroy the atomic structure of 2D materials and limit their practical applications. Fortunately, twisted structures are expected to validly suppress EEA through excellent interface quality. Here, we develop a non-destructive way to control EEA in WS2 homostructures by changing the interlayer twist angle, and systematically study the effect of interlayer twist angle on EEA, using fluorescence lifetime imaging measurement (FLIM) technology. Due to the large moiré potential at a small interlayer twist angle, the diffusion of excitons is hindered, and the EEA rate decreases from 1.01 × 10-1 cm2 s-1 in a 9° twisted WS2 homostructure to 4.26 × 10-2 cm2 s-1 in a 1° twisted WS2 homostructure. The results reveal the important role of the interlayer twist angle and EEA interaction in high photoluminescence quantum yield optoelectronic devices based on TMDC homostructures.

13.
Mol Cancer Res ; 20(3): 425-433, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34810212

RESUMO

Lung squamous cell carcinoma (LUSC) accounts for one of three of non-small cell lung carcinoma (NSCLC) and 30% of LUSC patients present with locally advanced, unresectable/medically inoperable disease, who are commonly treated with definitive chemoradiation. However, disease relapse in the radiation fields occurs in one of three cases. We aim to explore the underlying molecular mechanisms of chemoradiation resistance of LUSC. Patient-derived xenograft (PDX) models of LUSC were established in immunodeficient mice, followed by treatment with cisplatin in combination with clinically relevant courses of ionizing radiation (20, 30, and 40 Gy). The recurrent tumors were extracted for functional proteomics using reverse phase protein analysis (RPPA). We found that phospho-AKT-S473, phospho-AKT-T308, phospho-S6-S235/6, and phospho-GSK3ß-S9 were upregulated in the chemoradiation-resistant 20 Gy + cisplatin and 40 Gy + cisplatin tumors compared with those in the control tumors. Ingenuity pathway analysis of the RPPA data revealed that AKT-mTOR signaling was the most activated signaling pathway in the chemoradiation-resistant tumors. Similarly, elevated AKT-mTOR signaling was observed in stable 40 Gy and 60 Gy resistant HARA cell lines compared with the parental cell line. Accordingly, pharmacologic inhibition of mTOR kinase by Torin2 significantly sensitized LUSC cell lines to ionizing radiation. In conclusion, using chemoradiation-resistant PDX models coupled with RPPA proteomics analysis, we revealed that deregulation of AKT-mTOR signaling may contribute to the chemoradiation resistance of LUSC. IMPLICATIONS: Clonal selection of subpopulations with high AKT-mTOR signaling in heterogeneous tumors may contribute to relapse of LUSC after chemoradiation. mTOR kinase inhibitors may be promising radiosensitizing agents in upfront treatment to prevent acquired resistance.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/radioterapia , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Humanos , Pulmão/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Camundongos , Recidiva Local de Neoplasia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
14.
Nat Metab ; 4(5): 575-588, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35534729

RESUMO

Tumorigenesis is associated with elevated glucose and glutamine consumption, but how cancer cells can sense their levels to activate lipid synthesis is unknown. Here, we reveal that ammonia, released from glutamine, promotes lipogenesis via activation of sterol regulatory element-binding proteins (SREBPs), endoplasmic reticulum-bound transcription factors that play a central role in lipid metabolism. Ammonia activates the dissociation of glucose-regulated, N-glycosylated SREBP-cleavage-activating protein (SCAP) from insulin-inducible gene protein (Insig), an endoplasmic reticulum-retention protein, leading to SREBP translocation and lipogenic gene expression. Notably, 25-hydroxycholesterol blocks ammonia to access its binding site on SCAP. Mutating aspartate D428 to alanine prevents ammonia binding to SCAP, abolishes SREBP-1 activation and suppresses tumour growth. Our study characterizes the unknown role, opposite to sterols, of ammonia as a key activator that stimulates SCAP-Insig dissociation and SREBP-1 activation to promote tumour growth and demonstrates that SCAP is a critical sensor of glutamine, glucose and sterol levels to precisely control lipid synthesis.


Assuntos
Lipogênese , Neoplasias , Amônia , Glucose , Glutamina/metabolismo , Humanos , Insulina/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Esteróis/metabolismo
15.
Biomark Res ; 10(1): 39, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35658948

RESUMO

BACKGROUND: Given the observed antitumor activity of immune-checkpoint-inhibitors in patients with mismatch-repair deficient (MSI-H) tumors, we hypothesized that deficiency in homologous-recombination-repair (HRR) can also influence susceptibility. METHODS: Patients with disease progression on standard of care and for whom pembrolizumab had no FDA approved indication received pembrolizumab. Patients with MSI-H tumors were excluded. Objectives included immune-related objective response rate (iORR), progression-free survival (PFS) and 20-weeks-PFS. Pembrolizumab was given every 3 weeks and scans performed every six. We evaluated a triple-stain (FANCD2foci/DAPI/Ki67) functional assay of the Fanconi Anemia (FA) pathway: FATSI, in treated patients' archived tumors. The two-stage sample size of 20/39 patients evaluated an expected iORR≥20% in the whole population vs. the null hypothesis of an iORR≤5%, based on an assumed iORR≥40% in patients with functional FA deficiency, and < 10% in patients with intact HRR. An expansion cohort of MSI stable endometrial cancer (MS-EC) followed. Exploratory stool microbiome analyses in selected patients were performed. RESULTS: Fifty-two patients (45F,7M;50-evaluable) were enrolled. For the 39 in the two-stage cohort, response evaluation showed 2CR,5PR,11SD,21PD (iORR-18%). FATSI tumor analyses showed 29 competent (+) and 10 deficient (-). 2PR,9SD,17PD,1NE occurred among the FATSI+ (iORR-7%) and 2CR,3PR,2SD,3PD among the FATSI(-) patients (iORR-50%). mPFS and 20w-PFS were 43 days and 21% in FATSI+, versus 202 days and 70% in FATSI(-) patients. One PR occurred in the MS-EC expansion cohort. CONCLUSIONS: Pembrolizumab has meaningful antitumor activity in malignancies with no current FDA approved indications and FA functional deficiency. The results support further evaluation of FATSI as a discriminatory biomarker for population-selected studies.

16.
Theranostics ; 12(16): 7051-7066, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36276640

RESUMO

Rationale: The mitogen-activated protein kinase pathway (MAPK) is one of the major cancer-driving pathways found in non-small cell lung cancer (NSCLC) patients. ERK inhibitors (ERKi) have been shown to be effective in NSCLC patients with MAPK pathway mutations. However, like other MAPK inhibitors, ERKi rarely confers complete and durable responses. The mechanism of tumor relapse after ERKi treatment is yet defined. Methods: To best study the mechanism of tumor relapse after ERK inhibitor treatment in NSCLC patients, we treated various NSCLC cell lines and patient-derived xenograft (PDX) with ERK inhibitors and evaluated the enrichment of cancer stem cell (CSC) population. We then performed a Next-generation sequencing (NGS) to identify potential pathways that are responsible for the CSC enrichment. Further, the involvement of specific pathways was examined using molecular and cellular methods. Finally, we investigated the therapeutic benefits of ERKi treatment combined with JAK/STAT pathway inhibitor using cellular and xenograft NSCLC models. Results: We found that ERKi treatment expands the CSC population in NSCLC cells through enhanced epithelial-to-mesenchymal transition (EMT)-mediated cancer cell dedifferentiation. Mechanistically, ERK inactivation induces EMT via pSTAT3-mediated upregulation of Slug, in which, upregulation of miR-204 and downregulation of SPDEF, a transcription repressor of Slug, are involved. Finally, the JAK/STAT pathway inhibitor Ruxolitinib blocks the ERK inactivation-induced EMT and CSC expansion, as well as the tumor progression in xenograft models after ERKi treatment. Conclusions: This study revealed a potential tumor relapse mechanism of NSCLC after ERK inhibition through the unintended activation of the EMT program, ascertained the pSTAT-miR-204-SPDEF-Slug axis, and provided a promising combination inhibitor approach to prevent tumor relapse in patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Janus Quinases/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Transdução de Sinais , Fatores de Transcrição STAT/metabolismo , Recidiva Local de Neoplasia/genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Fatores de Transcrição/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , MicroRNAs/farmacologia , Regulação Neoplásica da Expressão Gênica
17.
Cancer Chemother Pharmacol ; 89(5): 721-735, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35435472

RESUMO

PURPOSE: BRCA1 or BRCA2 mutated cancers (BRCAmut) have intrinsic sensitivity to PARP inhibitors due to deficiency in homologous recombination-mediated DNA repair. There are similarities between BRCAmut and BRCAwt ovarian and basal-like breast cancers. This phase I study determined the recommended phase II dose (RP2D) and preliminary efficacy of the PARP inhibitor, veliparib (ABT-888), in these patients. PATIENTS AND METHODS: Patients (n = 98) were dosed with veliparib 50-500 mg twice daily (BID). The BRCAmut cohort (n = 70) contained predominantly ovarian (53%) and breast (23%) cancers; the BRCAwt cohort (n = 28) consisted primarily of breast cancer (86%). The MTD, DLT, adverse events, PK, PD, and clinical response were assessed. RESULTS: DLTs were grade 3 nausea/vomiting at 400 mg BID in a BRCAmut carrier, grade 2 seizure at 400 mg BID in a patient with BRCAwt cancer, and grade 2 seizure at 500 mg BID in a BRCAmut carrier. Common toxicities included nausea (65%), fatigue (45%), and lymphopenia (38%). Grade 3/4 toxicities were rare (highest lymphopenia at 15%). Overall response rate (ORR) was 23% (95% CI 13-35%) in BRCAmut overall, and 37% (95% CI 21-55%) at 400 mg BID and above. In BRCAwt, ORR was 8% (95% CI 1-26%), and clinical benefit rate was 16% (95% CI 4-36%), reflecting prolonged stable disease in some patients. PK was linear with dose and was correlated with response and nausea. CONCLUSIONS: Continuous veliparib is safe and tolerable. The RP2D was 400 mg BID. There is evidence of clinical activity of veliparib in patients with BRCAmut and BRCAwt cancers.


Assuntos
Linfopenia , Neoplasias Ovarianas , Neoplasias de Mama Triplo Negativas , Protocolos de Quimioterapia Combinada Antineoplásica , Proteína BRCA1/genética , Proteína BRCA2/genética , Benzimidazóis , Feminino , Humanos , Linfopenia/induzido quimicamente , Linfopenia/tratamento farmacológico , Náusea/induzido quimicamente , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Platina/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/efeitos adversos , Convulsões/induzido quimicamente , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
18.
Methods ; 52(4): 281-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20888418

RESUMO

Clinical trials and correlative laboratory research are increasingly reliant upon archived paraffin-embedded samples. Therefore, the proper processing of biological samples is an important step to sample preservation and for downstream analyses like the detection of a wide variety of targets including micro RNA, DNA and proteins. This paper analyzed the question whether routine fixation of cells and tissues in 10% buffered formalin is optimal for in situ and solution phase analyses by comparing this fixative to a variety of cross linking and alcohol (denaturing) fixatives. We examined the ability of nine commonly used fixative regimens to preserve cell morphology and DNA/RNA/protein quality for these applications. Epstein-Barr virus (EBV) and bovine papillomavirus (BPV)-infected tissues and cells were used as our model systems. Our evaluation showed that the optimal fixative in cell preparations for molecular hybridization techniques was "gentle" fixative with a cross-linker such as paraformaldehyde or a short incubation in 10% buffered formalin. The optimal fixatives for tissue were either paraformaldehyde or low concentration of formalin (5% of formalin). Methanol was the best of the non cross-linking fixatives for in situ hybridization and immunohistochemistry. For PCR-based detection of DNA or RNA, some denaturing fixatives like acetone and methanol as well as "gentle" cross-linking fixatives like paraformaldehyde out-performed other fixatives. Long term fixation was not proposed for DNA/RNA-based assays. The typical long-term fixation of cells and tissues in 10% buffered formalin is not optimal for combined analyses by in situ hybridization, immunohistochemistry, or--if one does not have unfixed tissues--solution phase PCR. Rather, we recommend short term less intense cross linking fixation if one wishes to use the same cells/tissue for in situ hybridization, immunohistochemistry, and solution phase PCR.


Assuntos
Fixadores , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Animais , Bovinos , Linhagem Celular , DNA Viral/análise , Formaldeído , Herpesvirus Humano 4 , Humanos , MicroRNAs/análise , Hibridização de Ácido Nucleico , Papillomaviridae , Inclusão em Parafina , Reação em Cadeia da Polimerase , Polímeros , Preservação Biológica , RNA , Fixação de Tecidos/métodos
19.
Sci Rep ; 11(1): 4420, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33627769

RESUMO

The Fanconi Anemia (FA) pathway is essential for human cells to maintain genomic integrity following DNA damage. This pathway is involved in repairing damaged DNA through homologous recombination. Cancers with a defective FA pathway are expected to be more sensitive to cross-link based therapy or PARP inhibitors. To evaluate downstream effectors of the FA pathway, we studied the expression of 734 different micro RNAs (miRNA) using NanoString nCounter miRNA array in two FA defective lung cancer cells and matched control cells, along with two lung tumors and matched non-tumor tissue samples that were deficient in the FA pathway. Selected miRNA expression was validated with real-time PCR analysis. Among 734 different miRNAs, a cluster of microRNAs were found to be up-regulated including an important cancer related micro RNA, miR-200C. MiRNA-200C has been reported as a negative regulator of epithelial-mesenchymal transition (EMT) and inhibits cell migration and invasion by promoting the upregulation of E-cadherin through targeting ZEB1 and ZEB2 transcription factors. miRNA-200C was increased in the FA defective lung cancers as compared to controls. AmpliSeq analysis showed significant reduction in ZEB1 and ZEB2 mRNA expression. Our findings indicate the miRNA-200C potentially play a very important role in FA pathway downstream regulation.


Assuntos
Anemia de Fanconi/genética , MicroRNAs/genética , Transdução de Sinais/genética , Células A549 , Caderinas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Proteínas de Homeodomínio/genética , Humanos , Neoplasias Pulmonares , Regulação para Cima/genética , Homeobox 2 de Ligação a E-box com Dedos de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética
20.
Nat Commun ; 12(1): 6081, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34667171

RESUMO

The development of the resistive switching cross-point array as the next-generation platform for high-density storage, in-memory computing and neuromorphic computing heavily relies on the improvement of the two component devices, volatile selector and nonvolatile memory, which have distinct operating current requirements. The perennial current-volatility dilemma that has been widely faced in various device implementations remains a major bottleneck. Here, we show that the device based on electrochemically active, low-thermal conductivity and low-melting temperature semiconducting tellurium filament can solve this dilemma, being able to function as either selector or memory in respective desired current ranges. Furthermore, we demonstrate one-selector-one-resistor behavior in a tandem of two identical Te-based devices, indicating the potential of Te-based device as a universal array building block. These nonconventional phenomena can be understood from a combination of unique electrical-thermal properties in Te. Preliminary device optimization efforts also indicate large and unique design space for Te-based resistive switching devices.

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