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1.
J Neurooncol ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38865011

RESUMO

INTRODUCTION: Central Neurocytoma (CN) is a rare, WHO grade 2 brain tumor that predominantly affects young adults. Gross total resection (GTR) is often curative for CNs, but the optimal treatment paradigm including incorporation of RT, following subtotal resection (STR) and for scarcer pediatric cases has yet to be established. METHODS: Patients between 2001 and 2021 with a pathologic diagnosis of CN were reviewed. Demographic, treatment, and tumor characteristics were recorded. Recurrence free survival (RFS) and overall survival (OS) were calculated according to the Kaplan Meier-method. Post-RT tumor volumetric regression analysis was performed. RESULTS: Seventeen adults (≥ 18 years old) and 5 children (< 18 years old) met the criteria for data analysis (n = 22). With a median follow-up of 6.9 years, there was no tumor-related mortality. Patients who received STR and/or had atypical tumors (using a cut-off of Ki-67 > 4%) experienced decreased RFS compared to those who received GTR and/or were without atypical tumors. RFS at 5 years for typical CNs was 67% compared to 22% for atypical CNs. Every pediatric tumor was atypical and 3/5 recurred within 5 years. Salvage RT following tumor recurrence led to no further recurrences within the timeframe of continued follow-up; volumetric analysis for 3 recurrent tumors revealed an approximately 80% reduction in tumor size. CONCLUSION: We provide encouraging evidence that CNs treated with GTR or with RT after tumor recurrence demonstrate good long-term tumor control.

2.
JAMA Netw Open ; 7(1): e2351906, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38231514

RESUMO

Importance: Black patients with endometrial cancer (EC) in the United States have higher mortality than patients of other races with EC. The prevalence of POLE and POLD1 pathogenic alterations in patients of different races with EC are not well studied. Objective: To explore the prevalence of and outcomes associated with POLE and POLD1 alterations in differential racial groups. Design, Setting, and Participants: This retrospective cohort study incorporated the largest available data set of patients with EC, including American Association for Cancer Research Project GENIE (Genomics Evidence Neoplasia Information Exchange; 5087 participants), Memorial Sloan Kettering-Metastatic Events and Tropisms (1315 participants), and the Cancer Genome Atlas Uterine Corpus Endometrial Carcinoma (517 participants), collected from 2015 to 2023, 2013 to 2021, and 2006 to 2012, respectively. The prevalence of and outcomes associated with POLE or POLD1 alterations in EC were evaluated across self-reported racial groups. Exposure: Patients of different racial groups with EC and with or without POLE or POLD1 alterations. Main Outcomes and Measures: The main outcome was overall survival. Data on demographic characteristics, POLE and POLD1 alteration status, histologic subtype, tumor mutation burden, fraction of genome altered, and microsatellite instability score were collected. Results: A total of 6919 EC cases were studied, of whom 444 (6.4%), 694 (10.0%), and 4869 (70.4%) patients were self-described as Asian, Black, and White, respectively. Within these large data sets, Black patients with EC exhibited a lower weighted average prevalence of pathogenic POLE alterations (0.5% [3 of 590 cases]) compared with Asian (6.1% [26 of 424]) or White (4.6% [204 of 4520]) patients. By contrast, the prevalence of POLD1 pathogenic alterations was 5.0% (21 cases), 3.2% (19 cases), and 5.6% (255 cases) in Asian, Black, and White patients with EC, respectively. Patients with POLD1 alterations had better outcomes regardless of race, histology, and TP53 alteration status. For a total of 241 clinically annotated Black patients with EC, a composite biomarker panel of either POLD1 or POLE alterations identified 7.1% (17 patients) with positive outcomes (1 event at 70 months follow up) in the small sample of available patients. Conclusions and Relevance: In this retrospective clinicopathological study of patients of different racial groups with EC, a composite biomarker panel of either POLD1 or POLE alteration could potentially guide treatment de-escalation, which is especially relevant for Black patients.


Assuntos
DNA Polimerase III , Neoplasias do Endométrio , Proteínas de Ligação a Poli-ADP-Ribose , Feminino , Humanos , Biomarcadores , DNA Polimerase III/genética , Neoplasias do Endométrio/epidemiologia , Neoplasias do Endométrio/genética , Prevalência , Estudos Retrospectivos , Proteínas de Ligação a Poli-ADP-Ribose/genética
3.
Sci Rep ; 14(1): 2126, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38267516

RESUMO

Identification of isocitrate dehydrogenase (IDH)-mutant glioma patients at high risk of early progression is critical for radiotherapy treatment planning. Currently tools to stratify risk of early progression are lacking. We sought to identify a combination of molecular markers that could be used to identify patients who may have a greater need for adjuvant radiation therapy machine learning technology. 507 WHO Grade 2 and 3 glioma cases from The Cancer Genome Atlas, and 1309 cases from AACR GENIE v13.0 datasets were studied for genetic disparities between IDH1-wildtype and IDH1-mutant cohorts, and between different age groups. Genetic features such as mutations and copy number variations (CNVs) correlated with IDH1 mutation status were selected as potential inputs to train artificial neural networks (ANNs) to predict IDH1 mutation status. Grade 2 and 3 glioma cases from the Memorial Sloan Kettering dataset (n = 404) and Grade 3 glioma cases with subtotal resection (STR) from Northwestern University (NU) (n = 21) were used to further evaluate the best performing ANN model as independent datasets. IDH1 mutation is associated with decreased CNVs of EGFR (21% vs. 3%), CDKN2A (20% vs. 6%), PTEN (14% vs. 1.7%), and increased percentage of mutations for TP53 (15% vs. 63%), and ATRX (10% vs. 54%), which were all statistically significant (p < 0.001). Age > 40 was unable to identify high-risk IDH1-mutant with early progression. A glioma early progression risk prediction (GlioPredictor) score generated from the best performing ANN model (6/6/6/6/2/1) with 6 inputs, including CNVs of EGFR, PTEN and CDKN2A, mutation status of TP53 and ATRX, patient's age can predict IDH1 mutation status with over 90% accuracy. The GlioPredictor score identified a subgroup of high-risk IDH1-mutant in TCGA and NU datasets with early disease progression (p = 0.0019, 0.0238, respectively). The GlioPredictor that integrates age at diagnosis, CNVs of EGFR, CDKN2A, PTEN and mutation status of TP53, and ATRX can identify a small cohort of IDH-mutant with high risk of early progression. The current version of GlioPredictor mainly incorporated clinically often tested genetic biomarkers. Considering complexity of clinical and genetic features that correlate with glioma progression, future derivatives of GlioPredictor incorporating more inputs can be a potential supplement for adjuvant radiotherapy patient selection of IDH-mutant glioma patients.


Assuntos
Aprendizado Profundo , Glioma , Adulto , Humanos , Isocitrato Desidrogenase/genética , Variações do Número de Cópias de DNA , Adjuvantes Imunológicos , Adjuvantes Farmacêuticos , Glioma/genética , Glioma/terapia , Proteínas Inibidoras de Quinase Dependente de Ciclina , Receptores ErbB/genética
4.
Thorac Cancer ; 14(23): 2269-2274, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37345618

RESUMO

BACKGROUND: In this study, we evaluated the potential of DNA polymerase epsilon (POLE) and DNA polymerase delta 1 (POLD1) as prognostic biomarkers for immune checkpoint inhibitor (ICI) treatment in patients with advanced stage non-small cell lung cancer (NSCLC). METHODS: Disease stage, PD-L1 positivity, histological subtypes, POLE/POLD1 mutation status, tumor mutation burden (TMB), and response to ICIs in NSCLC cases were derived from AACR GENIE dataset (n = 24 120), TCGA-Pan Lung Cancer dataset (n = 1144), AACR GENIE BPC NSCLC v2.0-public (n = 2004), and Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets dataset (n = 350). The smoking history from TCGA and AACR GENIE datasets was grouped into current, former or never-smokers. RESULTS: POLE and POLD1 genetic alterations were identified in 5% and 2.6% of NSCLC patients, respectively. Current smokers had 9% and 4% of POLE/POLD1 mutations, respectively, versus 1.7% for both POLE and POLD1 mutations prevalence in never-smokers. POLE/POLD1 mutations were associated with elevated mutation counts than those with wild-type (median mutation counts 16 vs. 7, p < 0.0001), more advanced disease stages (stage I disease 15.19% vs. 29.42%), more prevalent squamous histology subtype (21.69% vs. 9.05%, p = 0.0427), and a higher percentage of PD-L1 positivity (66.67% vs. 43.87%, p < 0.001). Treatment with ICIs improved survival in patients with both POLE/POLD1 mutated and those with TMB > 18 (p < 0.001). CONCLUSION: Current smokers have a five-fold increased risk of having POLE mutations than never-smokers. POLE/POLD1 mutation status and TMB > 18 can be a composite biomarker for selecting NSCLC patients with survival benefits to ICI treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Antígeno B7-H1/genética , Mutação , Biomarcadores Tumorais/genética , Imunoterapia , DNA Polimerase III/genética
5.
Gynecol Oncol ; 175: 97-106, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37336081

RESUMO

INTRODUCTION: Treatment for endometrial cancer (EC) is increasingly guided by molecular risk classifications. Here, we aimed at using machine learning (ML) to incorporate clinical and molecular risk factors to optimize risk assessment. METHODS: The Cancer Genome Atlas-Uterine Corpus Endometrial Carcinoma (n = 596), Memorial Sloan Kettering-Metastatic Events and Tropisms (n = 1315) and the American Association for Cancer Research Project Genomics Evidence Neoplasia Information Exchange (n = 4561) datasets were used to identify genetic alterations and clinicopathological features. Software packages including Keras, Pytorch, and Scikit Learn were tested to build artificial neural networks (ANNs) with a binary output as either intra-abdominal metastatic progression ('1') vs. non-metastatic ('0'). RESULTS: Black patients with EC have worse prognosis than White patients, adjusting for TP53 or POLE mutation status. Over 75% of Black patients carry TP53 mutations as compared to approximately 40% of White patients. Older age is associated with an increasing likelihood of TP53 mutation, high risk histology, and distant metastasis. For patients above age 70, 91% of Black and 60% of White EC patients carry TP53 mutations. A ML-based New Unified classifiCATion Score (NU-CATS) that incorporates age, race, histology, mismatch repair status, and TP53 mutation status showed 75% accuracy in prognosticating intra-abdominal progression. A higher NU-CATS is associated with an increasing risk of having positive pelvic or para-aortic lymph nodes and distant metastasis. NU-CATS was shown to outperform Leiden/TransPORTEC model for estimating risk of FIGO Stage I/II disease progression and survival in Black EC patients. CONCLUSION: The NU-CATS, a ML-based, cost-effective algorithm, incorporates diverse clinicopathologic and molecular variables of EC and yields superior prognostication of the risk of nodal involvement, distant metastasis, disease progression, and overall survival.


Assuntos
Neoplasias do Endométrio , Humanos , Feminino , Análise Custo-Benefício , Neoplasias do Endométrio/patologia , Prognóstico , Fatores de Risco , Mutação , Progressão da Doença
6.
7.
Neurooncol Adv ; 4(1): vdab167, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35059640

RESUMO

BACKGROUND: Pretreatment assessments for glioblastoma (GBM) patients, especially elderly or frail patients, are critical for treatment planning. However, genetic profiling with intracranial biopsy carries a significant risk of permanent morbidity. We previously demonstrated that the CUL2 gene, encoding the scaffold cullin2 protein in the cullin2-RING E3 ligase (CRL2), can predict GBM radiosensitivity and prognosis. CUL2 expression levels are closely regulated with its copy number variations (CNVs). This study aims to develop artificial neural networks (ANNs) for pretreatment evaluation of GBM patients with inputs obtainable without intracranial surgical biopsies. METHODS: Public datasets including Ivy-GAP, The Cancer Genome Atlas Glioblastoma (TCGA-GBM), and the Chinese Glioma Genome Atlas (CGGA) were used for training and testing of the ANNs. T1 images from corresponding cases were studied using automated segmentation for features of heterogeneity and tumor edge contouring. A ratio comparing the surface area of tumor borders versus the total volume (SvV) was derived from the DICOM-SEG conversions of segmented tumors. The edges of these borders were detected using the canny edge detector. Packages including Keras, Pytorch, and TensorFlow were tested to build the ANNs. A 4-layered ANN (8-8-8-2) with a binary output was built with optimal performance after extensive testing. RESULTS: The 4-layered deep learning ANN can identify a GBM patient's overall survival (OS) cohort with 80%-85% accuracy. The ANN requires 4 inputs, including CUL2 copy number, patients' age at GBM diagnosis, Karnofsky Performance Scale (KPS), and SvV ratio. CONCLUSION: Quantifiable image features can significantly improve the ability of ANNs to identify a GBM patients' survival cohort. Features such as clinical measures, genetic data, and image data, can be integrated into a single ANN for GBM pretreatment evaluation.

8.
Cancers (Basel) ; 13(5)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33804433

RESUMO

Glioblastoma multiforme (GBM) is the most common and devastating type of primary brain tumor, with a median survival time of only 15 months. Having a clinically applicable genetic biomarker would lead to a paradigm shift in precise diagnosis, personalized therapeutic decisions, and prognostic prediction for GBM. Radiogenomic profiling connecting radiological imaging features with molecular alterations will offer a noninvasive method for genomic studies of GBM. To this end, we analyzed over 3800 glioma and GBM cases across four independent datasets. The Chinese Glioma Genome Atlas (CGGA) and The Cancer Genome Atlas (TCGA) databases were employed for RNA-Seq analysis, whereas the Ivy Glioblastoma Atlas Project (Ivy-GAP) and The Cancer Imaging Archive (TCIA) provided clinicopathological data. The Clinical Proteomic Tumor Analysis Consortium Glioblastoma Multiforme (CPTAC-GBM) was used for proteomic analysis. We identified a simple three-gene transcriptome signature-SOCS3, VEGFA, and TEK-that can connect GBM's overall prognosis with genes' expression and simultaneously correlate radiographical features of perfusion imaging with SOCS3 expression levels. More importantly, the rampant development of neovascularization in GBM offers a promising target for therapeutic intervention. However, treatment with bevacizumab failed to improve overall survival. We identified SOCS3 expression levels as a potential selection marker for patients who may benefit from early initiation of angiogenesis inhibitors.

9.
Radiother Oncol ; 154: 36-44, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32918970

RESUMO

BACKGROUND AND PURPOSE: Positive epidermal growth factor receptor (EGFR) immunoreactivity in glioblastoma multiforme (GBM) often predicts poor radiation response. Meanwhile, all attempts to target EGFR pharmaceutically have been unsuccessful, mainly due to molecular heterogeneity of EGFR expression in GBM. A molecular biology-based and efficient way to access cellular protein levels of EGFR is urgently needed. EGFR, together with HIF-1α and Cyclin B1, is degraded via cullin2-RING E3 ligase (CRL2). It is worthwhile to investigate the possible involvement of CRL2 on GBM survival and radiosensitivity. MATERIALS AND METHODS: Clinicopathological features, radiographic images, survival data, RNA-Seq, copy number variations (CNVs), and other genetic changes were studied on over 3800 glioma and GBM cases, which are derived from 5 independent cohorts. These datasets include the Chinese Glioma Genome Atlas, The Cancer Genome Atlas, Ivy Glioblastoma Atlas Project, Clinical Proteomic Tumor Analysis Consortium, and the 2008 Parson's GBM dataset. RESULTS: Expression of CUL2, which encodes the scaffold protein cullin2 in the CRL2 E3 ligase, can predict GBM progression and survival rate. Cullin2 protein levels are inversely related to those of HIF-1α, VEGF-A, Cyclin B1, and EGFR. Elevated CUL2 expression predicts increased radiosensitivity and dampened signal intensities in perfusion imaging. CUL2 expression are regulated via CNVs, which are inheritable structural DNA variations. CONCLUSION: CUL2 expression levels and CNVs can be integrated as potential biomarkers in facilitating GBM and prognosis and radiosensitivity profiling.


Assuntos
Neoplasias Encefálicas , Proteínas Culina/genética , Glioblastoma , Biomarcadores , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA , Glioblastoma/genética , Glioblastoma/radioterapia , Humanos , Prognóstico , Proteômica , Tolerância a Radiação/genética , Ubiquitina-Proteína Ligases/genética
10.
Clin Case Rep ; 8(10): 1940-1942, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33088524

RESUMO

The mortality rates for Klebsiella pneumoniae invasive syndrome range from 4% to 11% with diabetes as a major risk factor. Early diagnosis of KPIS can decrease mortality rate with good outcomes due to sensitivity of K pneumoniae to antibiotics in KPIS.

11.
Transl Oncol ; 13(12): 100863, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32898767

RESUMO

About 70% of ovarian cancer (OvCa) cases are diagnosed at advanced stages (stage III/IV) with only 20-40% of them survive over 5 years after diagnosis. A reliably screening marker could enable a paradigm shift in OvCa early diagnosis and risk stratification. Age is one of the most significant risk factors for OvCa. Older women have much higher rates of OvCa diagnosis and poorer clinical outcomes. In this article, we studied the correlation between aging and genetic alterations in The Cancer Genome Atlas Ovarian Cancer dataset. We demonstrated that copy number variations (CNVs) and expression levels of the F-Box and Leucine-Rich Repeat Protein 20 (FBXL20), a substrate recognizing protein in the SKP1-Cullin1-F-box-protein E3 ligase, can predict OvCa overall survival, disease-free survival and progression-free survival. More importantly, FBXL20 copy number loss predicts the diagnosis of OvCa at a younger age, with over 60% of patients in that subgroup have OvCa diagnosed at age less than 60 years. Clinicopathological studies further demonstrated malignant histological and radiographical features associated with elevated FBXL20 expression levels. This study has thus identified a potential biomarker for OvCa prognosis.

12.
Front Oncol ; 10: 1517, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983997

RESUMO

As a dynamic regulator for short-lived protein degradation and turnover, the ubiquitin-proteasome system (UPS) plays important roles in various biological processes, including response to cellular stress, regulation of cell cycle progression, and carcinogenesis. Over the past decade, research on targeting the cullin-RING (really interesting new gene) E3 ligases (CRLs) in the UPS has gained great momentum with the entry of late-phase clinical trials of its novel inhibitors MLN4924 (pevonedistat) and TAS4464. Several preclinical studies have demonstrated the efficacy of MLN4924 as a radiosensitizer, mainly due to its unique cytotoxic properties, including induction of DNA damage response, cell cycle checkpoints dysregulation, and inhibition of NF-κB and mTOR pathways. Recently, the PROteolysis TArgeting Chimeras (PROTACs) technology was developed to recruit the target proteins for CRL-mediated polyubiquitination, overcoming the resistance that develops inevitably with traditional targeted therapies. First-in-class cell-permeable PROTACs against critical radioresistance conferring proteins, including the epidermal growth factor receptor (EGFR), androgen receptor (AR) and estrogen receptor (ER), cyclin-dependent kinases (CDKs), MAP kinase kinase 1 (MEK1), and MEK2, have emerged in the past 5 years. In this review article, we will summarize the most important research findings of targeting CRLs for radiosensitization.

13.
Aging (Albany NY) ; 12(17): 17380-17392, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32931454

RESUMO

Glioblastoma multiforme (GBM) is the deadliest type of brain tumor. The median survival time for patients with GBM is only 15 months, even following maximal surgical resection and chemotherapy and radiation therapy. A genetic biomarker could enable a paradigm shift in precise diagnosis, personalized therapeutics and prognosis. In this study, we employed the Chinese Glioma Genome Atlas, The Cancer Genome Atlas, and the Ivy Glioblastoma Atlas Project databases for RNA sequencing (RNA-seq) analysis and clinicopathological studies. We demonstrated that elevated expression of the RNF7, TCEB1, SOCS1 and SOCS3 genes, which encode components of cullin5-RING E3 ligase (CRL5), predict unfavorable GBM prognoses. In GBM and glioma cases carrying IDH1 mutations, SOCS1 and SOCS3 methylation was increased and their expression was downregulated. This study has thus identified a simple transcriptome signature for GBM prognosis.

14.
J Cancer ; 10(1): 92-104, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30662529

RESUMO

The novel tumor targeted nano-drug C-PC/CMC-CD59sp nanoparticles were constructed with carbocymethyl chitosan (CMC), C-phycocyanin (C-PC) and CD59 specific ligand peptide (CD59sp). The anti-tumor drug mechanism of the C-PC/CMC-CD59sp NPs was further explored in cervical cancer cells (HeLa and SiHa) in vitro and in vivo. We found that the C-PC/CMC-CD59sp NPs could inhibit the proliferation and induce G0/G1 cell cycle arrest in cervical cancer HeLa and SiHa cells, and the cell proliferation was reduced in a dose-dependent manner. We further found that the C-PC/CMC-CD59sp NPs regulated the cell cycle via up-regulating the expression of p21, and then down-regulating the expressions of Cyclin D1 and CDK4 in vivo. Compared with C-PC and C-PC/CMC NPs, the pro-apoptosis effects of the C-PC/CMC-CD59sp NPs were more significant for HeLa and SiHa cells in vitro. Moreover, the C-PC/CMC-CD59sp NPs up-regulated the expression of cleaved caspase-3 and down-regulated the expression of bcl-2. In addition, compared with C-PC and C-PC/CMC, the C-PC/CMC-CD59sp NPs significantly inhibited MMP-2 protein expression in vivo. Our data suggested that the anti-tumor effects of C-PC/CMC-CD59sp NPs were better than C-PC and C-PC/CMC NPs. Our laboratory constructed a new drug delivery system and proved the effective antitumor effects of C-PC/CMC-CD59sp, which would widen the application of C-PC as a potential anti cervical cancer drug.

15.
Chemosphere ; 210: 1185-1192, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30208544

RESUMO

Antibiotic pollution in nitrogen contained wastewater is an urgent issue. In this study, the nitrogen removal, biofilm property and microbial community of Anammox system were investigated with elevated norfloxacin (NOR) feeding. Batch experiments were carried out to detect the specific anammox activity (SAA) in each phase. Anammox system could resist NOR in 0.001-50 mg L-1, in which the nitrogen removal was firstly limited to 0.220 from the initial 0.345 by NOR suppression and then regained to 0.354 kg m-3 d-1 after acclimatization. SAA decreased to 7.56 from the initial 10.84 and then climbed up to 11.01 mg g-1 SS, while the relative abundance of Candidatus Kuenenia decreased to 11.33% and then picked up to 25.28% from the initial 20.74%. The suppression threshold on Anammox was calculated as 50-100 mg L-1 NOR, the NRR, SAA and Candidatus Kuenenia abundance all recovered to almost the initial level when NOR feeding was terminated.


Assuntos
Antibacterianos/efeitos adversos , Biofilmes/crescimento & desenvolvimento , Nitrogênio/química , Norfloxacino/efeitos adversos
16.
Oncotarget ; 9(5): 5529-5544, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29464016

RESUMO

De novo and acquired drug resistance and subsequent relapse remain major challenges in acute lymphoblastic leukemia (ALL). We previously identified that pevonedistat (TAK-924, MLN4924), a first-in-class inhibitor of NEDD8 activating enzyme (NAE), elicits ER stress and has potent in vitro and in vivo efficacy against ALL. However, in pevonedistat-treated ALL cell lines, we found consistent activation of the pro-survival MEK/ERK pathway, which has been associated with relapse and poor outcome in ALL. We uncovered that inhibition of the MEK/ERK pathway in vitro and in vivo sensitized ALL cells to pevonedistat. The observed synergistic apoptotic effect appears to be mediated by inhibition of the MEK/ERK pro-survival cascade leading to de-repression of the pro-apoptotic BIM protein. Mechanistically, Ca2+ influx via the Ca2+-release-activated Ca2+ (CRAC) channel induced protein kinase C ß2 (PKC-ß2) was responsible for activation of the MEK/ERK pathway in pevonedistat-treated ALL cells. Sequestration of Ca2+ using BAPTA-AM or blockage of store-operated Ca2+ entry (SOCE) using BTP-2 both attenuated the compensatory activation of MEK/ERK signaling in pevonedistat-treated ALL cells. Pevonedistat significantly altered the expression of Orai1 and stromal interaction molecule 1 (STIM1), resulting in significantly decreased STIM1 protein levels relative to Orai1. Further, we identified eIF2α as an important post-transcriptional regulator of STIM1, suggesting that pevonedistat-induced eIF2α de-phosphorylation selectively down-regulates translation of STIM1 mRNA. Consequently, our data suggest that pevonedistat potentially activates SOCE and promotes Ca2+ influx leading to activation of the MEK/ERK pathway by altering the stoichiometric Orai1:STIM1 ratio and inducing ER stress in ALL cells.

17.
Bioresour Technol ; 243: 93-99, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28668561

RESUMO

In this study, a membrane bioreactor (MBR) was adopted for completely autotrophic nitrogen removal over nitrite (CANON) process. Zinc oxide nanoparticles (ZnO NPs) was step-wise increased to analyze the influence on nitrogen removal, microbial activity and microbial communities. Finally ZnO NPs was removed to study its recovery capability. The bioactivities of ammonia-oxidizing bacteria (AOB), anaerobic ammonia-oxidizing bacteria (AAOB) and nitrite-oxidizing bacteria (NOB) were detected by batch experiments. Results showed that the ZnO NPs with low concentration (≤5mgL-1) was profitable for nitrogen removal while the high concentration performed inhibition, and it lowered the abundance of both AOB and NOB while enhanced that of AAOB. ZnO NPs with high concentration (≥10mgL-1) suppressed both AOB and AAOB, and long-term exposure within ZnO NPs led to microbial diversity decrease. The inhibition threshold of ZnO NPs on CANON process was 10mgL-1, and the profitable concentration was 1mgL-1.


Assuntos
Desnitrificação , Nanopartículas , Óxido de Zinco , Reatores Biológicos , Nitritos , Nitrogênio
18.
Leuk Res ; 50: 1-10, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27626202

RESUMO

Acute lymphoblastic leukemia (ALL) is the leading cause of cancer-related death in children, and cure rates for adults remain dismal. Further, effective treatment strategies for relapsed/refractory ALL remain elusive. We previously uncovered that ALL cells are prone to apoptosis via endoplasmic reticulum (ER) stress/unfolded protein response (UPR)-mediated mechanisms. We investigated the antineoplastic activity of pevonedistat®, a novel NEDD8-activating enzyme inhibitor that targets E3 cullin-RING ligases (CRLs) dependent proteasomal protein degradation, in ALL. Herein, we report that pevonedistat induces apoptosis in ALL cells by dysregulating the translational machinery leading to induction of proteotoxic/ER stress and UPR-mediated cell death. Mechanistically, pevonedistat led to P-eIF2a dephosphorylation causing atypical proteotoxic/ER stress from failure to halt protein translation via the UPR and upregulation of mTOR/p70S6K. Additional studies revealed that pevonedistat re-balanced the homeostasis of pro- and anti-apoptotic proteins to favor cell death through altered expression and/or activity of Mcl-1, NOXA, and BIM, suggesting that pevonedistat has a "priming" effect on ALL by altering the apoptotic threshold through modulation of Mcl-1 activity. Further, we demonstrated that pevonedistat synergizes with selected anti-leukemic agents in vitro, and prolongs survival of NSG mice engrafted with ALL cells, lending support for the use of pevonedistat as part of a multi-agent approach.


Assuntos
Ciclopentanos/farmacologia , Fator de Iniciação 2 em Eucariotos/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Pirimidinas/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Ubiquitinas/antagonistas & inibidores , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Animais , Antineoplásicos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ciclopentanos/uso terapêutico , Estresse do Retículo Endoplasmático , Inibidores Enzimáticos , Xenoenxertos , Humanos , Camundongos , Proteína NEDD8 , Pirimidinas/uso terapêutico
19.
Biotechnol Lett ; 38(12): 2059-2069, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27578392

RESUMO

OBJECTIVES: To analyze the anti-insect mechanism of viral pesticide AcMNPV-BmK IT(P10/PH) in the host Spodoptera frugiperda 9 (Sf9) cells. RESULTS: Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV)- mediated expression of BmK IT, regulated by P10 protein promoter (P10) and polyhedrosis promoter (PH), promoted the replication of progeny virus in host Sf9 cells. AcMNPV-BmK IT(P10) could accelerate the budding process (or speed) of budded virus (BV) in Sf9 cells. The impact of AcMNPV-BmK IT(P10) on the nuclear polymerization of filamentous actin (F-actin) participated in regulating the accelerated budding process. Unexpectedly, both AcMNPV-BmK IT(P10) and AcMNPV-BmK IT(PH) delayed the nuclear polymerization of F-actin and promoted the clearance of F-actin in the nucleus. SfP53, an important apoptosis factor, was involved in the regulation of AcMNPV-BmK IT(P10/PH) in Sf9 cells. AcMNPV-BmK IT(P10/PH) could also delay and promote the nuclear recruitment of SfP53 after 27 h post infection (h p.i.). CONCLUSION: SfP53 and F-actin are the targets of viral pesticide AcMNPV-BmK IT (P10/PH) in host Sf9 cells, which provides the experimental basis for the development of recombinant baculovirus biopesticides.


Assuntos
Actinas/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Animais , Western Blotting , Imunofluorescência , Gliceraldeído-3-Fosfato Desidrogenases/genética , Nucleopoliedrovírus/metabolismo , Nucleopoliedrovírus/patogenicidade , Praguicidas/metabolismo , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Sf9
20.
Biotechnol Lett ; 38(10): 1673-81, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27323750

RESUMO

OBJECTIVES: To analyze the mechanisms underlying the impact of recombinant Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV)-mediated BmK IT expression on the function of baculovirus GP64 envelope fusion protein and progeny virus production. RESULTS: Viral propagation assay indicated that overexpression GP64 could promote replication of AcMNPV. AcMNPV-mediated expression of BmK IT also promoted replication of AcMNPV. Immunofluorescence analysis showed BmK IT, which was regulated by very early promoter IE1 in AcMNPV, could make the GP64 protein move to the cytomembrane soon after transfection. BmK IT, which is regulated by P10 protein promoter (P10) and polyhedrosis promoter (PH), could promote the expression of GP64. CONCLUSION: BmK IT, regulated by very early promoter IE1, P10 protein promoter (P10) and PH, accelerated the expression of GP64 protein, promoted its early cytomembrane localization and then triggered virus budding and progeny virus production.


Assuntos
Nucleopoliedrovírus/fisiologia , Venenos de Escorpião/metabolismo , Spodoptera/virologia , Proteínas Virais de Fusão/metabolismo , Animais , Membrana Celular/metabolismo , Regulação Viral da Expressão Gênica , Nucleopoliedrovírus/genética , Regiões Promotoras Genéticas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Venenos de Escorpião/genética , Células Sf9 , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Proteínas Virais de Fusão/genética , Ensaio de Placa Viral , Replicação Viral
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