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1.
World J Microbiol Biotechnol ; 40(5): 136, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38499730

ABSTRACT

Photosynthetic diazotrophs expressing iron-only (Fe-only) nitrogenase can be developed into a promising biofertilizer, as it is independent on the molybdenum availability in the soil. However, the expression of Fe-only nitrogenase in diazotrophs is repressed by the fixed nitrogen of the soil, limiting the efficiency of nitrogen fixation in farmland with low ammonium concentrations that are inadequate for sustainable crop growth. Here, we succeeded in constitutively expressing the Fe-only nitrogenase even in the presence of ammonium by controlling the transcription of Fe-only nitrogenase gene cluster (anfHDGK) with the transcriptional activator of Mo nitrogenase (NifA*) in several different ways, indicating that the engineered NifA* strains can be used as promising chassis cells for efficient expression of different types of nitrogenases. When applied as a biofertilizer, the engineered Rhodopseudomonas palustris effectively stimulated rice growth, contributing to the reduced use of chemical fertilizer and the development of sustainable agriculture.


Subject(s)
Ammonium Compounds , Oryza , Nitrogen Fixation , Nitrogenase/genetics , Nitrogenase/metabolism , Nitrogen/metabolism , Soil
2.
Phys Chem Chem Phys ; 25(17): 12220-12230, 2023 May 03.
Article in English | MEDLINE | ID: mdl-37073883

ABSTRACT

The catalytic performance of titanosilicates involving hydrogen peroxide (H2O2) as the oxidant is strongly influenced by the solvents. Until now, there is still a lack of a universal principle that can guide the choice of a solvent. Herein, the kinetics of H2O2 activation catalyzed by various titanosilicates in different solvents is investigated, and an isokinetic compensation effect is concluded. This indicates that the solvent participates in the H2O2 activation process for the formation of a Ti-OOH species. Additionally, the results of isotopically labeled infrared spectra preliminarily confirm that the solvent acts as the mediator to promote the proton transfer during the H2O2 activation process. The catalytic activities of a series of TS-1 catalysts toward 1-hexene epoxidation are compared, which include Ti(OSi)3OH species with a range of densities but a constant total Ti content. This reveals that the solvent effect is closely related to the Ti active sites of these TS-1 catalysts. Based on these results, a principle for the rational choice of solvent for this catalytic process is proposed. ROH is found to be the mediator for Ti(OSi)4 sites, and methanol, which has a strong proton-donating ability, is the best solvent for these sites. However, for the Ti(OSi)3OH sites, water (H2O) is the mediator, and a weaker hydrogen bonding between H2O molecules promotes proton transfer more effectively. The solvent influences the catalytic performance by perturbing the hydrogen bonds between the H2O molecules, and aprotic acetonitrile, which has a strong ability to break the hydrogen bonding network between H2O molecules, is the best solvent for Ti(OSi)3OH sites. This study provides experimental evidence that the solvent promotes the catalytic performance of titanosilicates by assisting the proton transfer during the catalytic H2O2 activation process, which will pave the way toward the rational choice of solvent for the titanosilicate-catalyzed oxidation systems.

3.
Int J Mol Sci ; 22(19)2021 Sep 30.
Article in English | MEDLINE | ID: mdl-34638991

ABSTRACT

Selenoproteins play important roles in many cellular functions and biochemical pathways in mammals. Our previous study showed that the deficiency of the 15 kDa selenoprotein (Selenof) significantly reduced the formation of aberrant crypt foci (ACF) in a mouse model of azoxymethane (AOM)-induced colon carcinogenesis. The objective of this study was to examine the effects of Selenof on inflammatory tumorigenesis, and whether dietary selenium modified these effects. For 20 weeks post-weaning, Selenof-knockout (KO) mice and littermate controls were fed diets that were either deficient, adequate or high in sodium selenite. Colon tumors were induced with AOM and dextran sulfate sodium. Surprisingly, KO mice had drastically fewer ACF but developed a similar number of tumors as their littermate controls. Expression of genes important in inflammatory colorectal cancer and those relevant to epithelial barrier function was assessed, in addition to structural differences via tissue histology. Our findings point to Selenof's potential role in intestinal barrier integrity and structural changes in glandular and mucin-producing goblet cells in the mucosa and submucosa, which may determine the type of tumor developing.


Subject(s)
Aberrant Crypt Foci/diet therapy , Aberrant Crypt Foci/metabolism , Carcinogenesis/drug effects , Colonic Neoplasms/blood , Colonic Neoplasms/diet therapy , Intestinal Mucosa/metabolism , Selenoproteins/metabolism , Sodium Selenite/administration & dosage , Trace Elements/administration & dosage , Aberrant Crypt Foci/genetics , Animals , Azoxymethane/adverse effects , Carcinogenesis/genetics , Colonic Neoplasms/chemically induced , Colonic Neoplasms/genetics , Cytokines/blood , Dextran Sulfate/adverse effects , Diet/methods , Disease Models, Animal , Gene Expression Regulation, Neoplastic/drug effects , Intestinal Mucosa/drug effects , Male , Mice , Mice, Knockout , Selenoproteins/genetics , Signal Transduction/drug effects , Signal Transduction/genetics
4.
Nature ; 481(7381): 376-9, 2011 Dec 21.
Article in English | MEDLINE | ID: mdl-22190036

ABSTRACT

The human APOBEC3 cytidine deaminases are potent inhibitors of diverse retroviruses, including human immunodeficiency virus-1 (HIV-1). HIV-1 Vif forms an E3 ubiquitin ligase complex with cullin 5 (CUL5), elongin B and elongin C , which promotes the polyubiquitination and degradation of APOBEC3 substrates. Here we demonstrate in human T cells that core binding factor ß (CBF-ß) is a key regulator of the evasion of HIV-1 from the host defence mediated by APOBEC3. CBF-ß, the non-DNA-binding subunit of a heterodimeric transcription factor, regulates the folding and DNA-binding activity of partner RUNX family proteins, which have important roles in the development and differentiation of diverse cell types, including T lymphocytes. In our study, knockdown of endogenous CBF-ß blocked Vif-induced APOBEC3G polyubiquitination and degradation. CBF-ß was not required for the interaction between Vif and APOBEC3G, yet was essential for the assembly of the Vif-CUL5 E3-ubiquitin-ligase complex. CBF-ß proved to be a unique regulator of primate lentiviral Vif and not a general component of the CUL5 E3 ubiquitin ligase. We show that Vif and CBF-ß physically interact, and that the amino-terminal region of Vif is required for this interaction. Furthermore, interactions with Vif required regions in CBF-ß that are not involved in RUNX protein binding. Considering the importance of the interaction between Vif and CBF-ß, disrupting this interaction represents an attractive pharmacological intervention against HIV-1.


Subject(s)
Cell Differentiation , Core Binding Factor beta Subunit/metabolism , HIV-1/physiology , Host-Pathogen Interactions , Immune Evasion , T-Lymphocytes/cytology , vif Gene Products, Human Immunodeficiency Virus/metabolism , APOBEC-3G Deaminase , Cell Line , Core Binding Factor alpha Subunits/metabolism , Core Binding Factor beta Subunit/chemistry , Core Binding Factor beta Subunit/deficiency , Core Binding Factor beta Subunit/genetics , Cullin Proteins/metabolism , Cytidine Deaminase/genetics , Cytidine Deaminase/metabolism , Gene Knockdown Techniques , HEK293 Cells , HIV-1/genetics , HIV-1/immunology , Humans , Immunoprecipitation , Models, Molecular , Protein Binding , Proteolysis , T-Lymphocytes/immunology , Ubiquitin-Protein Ligases/metabolism , Ubiquitination , vif Gene Products, Human Immunodeficiency Virus/chemistry , vif Gene Products, Human Immunodeficiency Virus/genetics
5.
Br J Cancer ; 113(6): 894-901, 2015 Sep 15.
Article in English | MEDLINE | ID: mdl-26291055

ABSTRACT

BACKGROUND: Despite good initial response to chemotherapy, 30% of Ewing's sarcoma (EWS) patients with localised tumours develop recurrent disease, associated with poor prognosis. The aim of this study was to address this challenge by conducting preclinical evaluation of a death receptor targeted agent in vitro and in vivo, and by identifying predictive biomarkers. METHODS: Cell viability assays, drug dose responses, immunoblots, rescue with gene transfer, mice tumour models, and statistical comparisons of tumour growth and Kaplan-Meier survival curves. RESULTS: This study shows that many EWS cell lines are selectively sensitive to a death receptor DR5 antibody and are more resistant to a DR4 antibody. Preclinical evaluation of these cell lines indicates their sensitivity to human DR5 agonist antibody conatumumab in vitro, which induces rapid activation of caspase-8 and apoptosis. We also found that sensitivity to conatumumab correlates with expression of caspase-8. Furthermore, the catalytic activity of caspase-8 is both necessary and sufficient to confer this sensitivity. In vivo, conatumumab is active against an EWS cell line and a patient-derived xenograft with higher caspase-8 expression, but is not effective against another with lower caspase-8 expression. CONCLUSIONS: These studies suggest the potential of conatumumab as a therapeutic agent against EWS and caspase-8 as a predictive biomarker for sensitivity.


Subject(s)
Antibodies, Monoclonal/pharmacology , Biomarkers, Tumor/metabolism , Bone Neoplasms/drug therapy , Caspase 8/metabolism , Receptors, TNF-Related Apoptosis-Inducing Ligand/immunology , Sarcoma, Ewing/drug therapy , Animals , Apoptosis , Biomarkers, Tumor/immunology , Bone Neoplasms/enzymology , Bone Neoplasms/immunology , Cell Line, Tumor , Drug Resistance, Neoplasm , Female , Heterografts , Humans , Mice , Random Allocation , Receptors, TNF-Related Apoptosis-Inducing Ligand/agonists , Sarcoma, Ewing/enzymology , Sarcoma, Ewing/immunology , Xenograft Model Antitumor Assays/methods
6.
BJU Int ; 116(4): 546-55, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25407442

ABSTRACT

OBJECTIVE: TRC105 is a chimeric immunoglobulin G1 monoclonal antibody that binds endoglin (CD105). This phase I open-label study evaluated the safety, pharmacokinetics and pharmacodynamics of TRC105 in patients with metastatic castration-resistant prostate cancer (mCRPC). PATIENTS AND METHODS: Patients with mCRPC received escalating doses of i.v. TRC105 until unacceptable toxicity or disease progression, up to a predetermined dose level, using a standard 3 + 3 phase I design. RESULTS: A total of 20 patients were treated. The top dose level studied, 20 mg/kg every 2 weeks, was the maximum tolerated dose. Common adverse effects included infusion-related reaction (90%), low grade headache (67%), anaemia (48%), epistaxis (43%) and fever (43%). Ten patients had stable disease on study and eight patients had declines in prostate specific antigen (PSA). Significant plasma CD105 reduction was observed at the higher dose levels. In an exploratory analysis, vascular endothelial growth factor (VEGF) was increased after treatment with TRC105 and VEGF levels were associated with CD105 reduction. CONCLUSION: TRC105 was tolerated at 20 mg/kg every other week with a safety profile distinct from that of VEGF inhibitors. A significant induction of plasma VEGF was associated with CD105 reduction, suggesting anti-angiogenic activity of TRC105. An exploratory analysis showed a tentative correlation between the reduction of CD105 and a decrease in PSA velocity, suggestive of potential activity of TRC105 in the patients with mCRPC. The data from this exploratory analysis suggest that rising VEGF level is a possible compensatory mechanism for TRC105-induced anti-angiogenic activity.


Subject(s)
Antibodies, Monoclonal , Antineoplastic Agents , Prostatic Neoplasms, Castration-Resistant/drug therapy , Aged , Aged, 80 and over , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal/blood , Antibodies, Monoclonal/pharmacokinetics , Antibodies, Monoclonal/therapeutic use , Antigens, CD/blood , Antineoplastic Agents/adverse effects , Antineoplastic Agents/blood , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/therapeutic use , Endoglin , Humans , Male , Middle Aged , Prostate-Specific Antigen/blood , Prostatic Neoplasms, Castration-Resistant/epidemiology , Receptors, Cell Surface/antagonists & inhibitors , Receptors, Cell Surface/blood , Vascular Endothelial Growth Factor A/blood
7.
Lancet Oncol ; 15(2): 191-200, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24439931

ABSTRACT

BACKGROUND: No standard treatment exists for refractory or relapsed advanced thymic epithelial tumours. We investigated the efficacy of cixutumumab, a fully human IgG1 monoclonal antibody targeting the insulin-like growth factor 1 receptor in thymic epithelial tumours after failure of previous chemotherapy. METHODS: Between Aug 25, 2009, and March 27, 2012, we did a multicentre, open-label, phase 2 trial in patients aged 18 years or older with histologically confirmed recurrent or refractory thymic epithelial tumours. We enrolled individuals who had progressed after at least one previous regimen of platinum-containing chemotherapy, had an Eastern Cooperative Oncology Group performance status of 0 or 1, and had measurable disease and adequate organ function. Eligible patients received intravenous cixutumumab (20 mg/kg) every 3 weeks until disease progression or development of intolerable toxic effects. The primary endpoint was the frequency of response, analysed on an intention-to-treat basis. We also did pharmacodynamic studies. This trial is registered with ClinicalTrials.gov, number NCT00965250. FINDINGS: 49 patients were enrolled (37 with thymomas and 12 with thymic carcinomas) who received a median of eight cycles of cixutumumab (range 1-46). At the final actuarial analysis when follow-up data were updated (Nov 30, 2012), median potential follow-up (from on-study date to most current follow-up date) was 24·0 months (IQR 17·3-36·9). In the thymoma cohort, five (14%) of 37 patients (95% CI 5-29) achieved a partial response, 28 had stable disease, and four had progressive disease. In the thymic carcinoma cohort, none of 12 patients (95% CI 0-26) had a partial response, five had stable disease, and seven had progressive disease. The most common grade 3-4 adverse events in both cohorts combined were hyperglycaemia (five [10%]), lipase elevation (three [6%]), and weight loss, tumour pain, and hyperuricaemia (two each [4%]). Nine (24%) of 37 patients with thymoma developed autoimmune conditions during treatment (five were new-onset disorders), the most common of which was pure red-cell aplasia. Two (4%) patients died; one was attributed to disease progression and the other to disease-related complications (respiratory failure, myositis, and an acute coronary event), which could have been precipitated by treatment with cixutumumab. INTERPRETATION: Cixutumumab monotherapy is well-tolerated and active in relapsed thymoma. Development of autoimmunity during treatment needs further investigation. FUNDING: Division of Cancer Treatment and Diagnosis at the National Cancer Institute (National Institutes of Health), ImClone Systems.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antineoplastic Agents/therapeutic use , Neoplasm Recurrence, Local/drug therapy , Neoplasms, Glandular and Epithelial/drug therapy , Thymus Neoplasms/drug therapy , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal, Humanized , Antineoplastic Agents/adverse effects , Autoimmunity/drug effects , Disease Progression , Disease-Free Survival , Female , Humans , Intention to Treat Analysis , Kaplan-Meier Estimate , Male , Middle Aged , Neoplasm Recurrence, Local/immunology , Neoplasm Recurrence, Local/mortality , Neoplasm Recurrence, Local/pathology , Neoplasms, Glandular and Epithelial/immunology , Neoplasms, Glandular and Epithelial/mortality , Neoplasms, Glandular and Epithelial/pathology , Receptor, IGF Type 1/antagonists & inhibitors , Receptor, IGF Type 1/immunology , Thymus Neoplasms/immunology , Thymus Neoplasms/mortality , Thymus Neoplasms/pathology , Time Factors , Treatment Outcome
8.
Front Oncol ; 14: 1386190, 2024.
Article in English | MEDLINE | ID: mdl-38706610

ABSTRACT

Background: LMB-100 is a mesothelin (MSLN)-targeting recombinant immunotoxin (iTox) carrying a Pseudomonas exotoxin A payload that has shown promise against solid tumors, however, efficacy is limited by the development of neutralizing anti-drug antibodies (ADAs). Tofacitinib is an oral Janus Kinase (JAK) inhibitor that prevented ADA formation against iTox in preclinical studies. Methods: A phase 1 trial testing LMB-100 and tofacitinib in patients with MSLN-expressing cancers (pancreatic adenocarcinoma, n=13; cholangiocarcinoma, n=1; appendiceal carcinoma, n=1; cystadenocarcinoma, n=1) was performed to assess safety and to determine if tofacitinib impacted ADA formation. Participants were treated for up to 3 cycles with LMB-100 as a 30-minute infusion on days 4, 6, and 8 at two dose levels (100 and 140 µg/kg) while oral tofacitinib was administered for the first 10 days of the cycle (10 mg BID). Peripheral blood was collected for analysis of ADA levels, serum cytokines and circulating immune subsets. Results: The study was closed early due to occurrence of drug-induced pericarditis in 2 patients. Pericarditis with the combination was not reproducible in a transgenic murine model containing human MSLN. Two of 4 patients receiving all 3 cycles of treatment maintained effective LMB-100 levels, an unusual occurrence. Sustained increases in systemic IL-10 and TNF-α were seen, a phenomenon not observed in prior LMB-100 studies. A decrease in activated T cell subsets and an increase in circulating immunosuppressive myeloid populations occurred. No radiologic decreases in tumor volume were observed. Discussion: Further testing of tofacitinib to prevent ADA formation is recommended in applicable non-malignant disease settings. Clinical trial registration: https://www.clinicaltrials.gov/study/NCT04034238.

9.
Cancer Med ; 12(4): 4236-4249, 2023 02.
Article in English | MEDLINE | ID: mdl-36208017

ABSTRACT

LMB-100 is a novel immune-conjugate (immunotoxin) that targets mesothelin. A phase 1/2 clinical trial was conducted (NCT02810418) with primary objectives assessing the safety and efficacy of LMB-100 ± nab-paclitaxel. Participant blood samples were analyzed for changes in serum cytokines and circulating immune cell subsets associated with response or toxicity. On Arm A, participants (n = 20) received standard 30-minute LMB-100 infusion with nab-paclitaxel. Although clinical efficacy was observed, the combination caused intolerable capillary leak syndrome (CLS), a major toxicity of unclear etiology that affects many immunotoxin drugs. Participants developing CLS experienced rapid elevations in IFNγ and IL-8 compared to those without significant CLS, along with midcycle increases in Ki-67- CD4 T cells that were CD38, HLA-DR, or TIM3 positive. Additionally, a strong increase in activated CD4 and CD8 T cells and a concurrent decrease in Tregs were seen in the single Arm A patient achieving a partial response. In Arm B, administration of single agent LMB-100 to participants (n = 20) as a long infusion given over 24-48 h was investigated based on pre-clinical data that this format could reduce CLS. An optimal dose and schedule of long infusion LMB-100 were identified, but no clinical efficacy was observed even in patients receiving LMB-100 in combination with nab-paclitaxel. Despite this, both Arm A and B participants experienced increases in specific subsets of proliferating CD4 and CD8 T cells following Cycle 1 treatment. In summary, LMB-100 treatment causes systemic immune activation. Inflammatory and immune changes that accompany drug associated CLS were characterized for the first time.


Subject(s)
Immunoconjugates , Immunotoxins , Humans , Immunotoxins/therapeutic use , Antibodies, Monoclonal , Paclitaxel/therapeutic use , Albumins
10.
Int J Cancer ; 131(9): 2143-52, 2012 Nov 01.
Article in English | MEDLINE | ID: mdl-22323052

ABSTRACT

Insulin growth factor-I receptor (IGF-IR) is expressed in mesothelioma and therefore an attractive target for therapy. The antitumor activity of cixutumumab, a humanized monoclonal antibody to IGF-IR, in mesothelioma and relationship to IGF-IR expression was investigated using eight early passage tumor cells obtained from patients, nine established cell lines and an in vivo human mesothelioma tumor xenograft model. Although IGF-IR expression at the mRNA and protein level was present in all mesothelioma cells, using a quantitative ELISA immunoassay, there was considerable variability of IGF-IR expression ranging from 1 to 14 ng/mg of lysate. Using flow cytometry, the number of IGF-IR surface receptors varied from ≈ 2,000 to 50,000 sites/cell. Cells expressing >10,000 sites/cell had greater than 10% growth inhibition when treated with cixutumumab (100 µg/ml). Cixutumumab also induced antibody-dependent cell-mediated toxicity (>10% specific lysis) in cell lines, which had >20,000 IGF-IR sites/cell. Treatment with cixutumumab decreased phosphorylation of IGF-IR, Akt and Erk in cell lines, H226 and H28 having 24,000 and 51,000 IGF-IR sites/cell, respectively, but not in the cell line H2052 with 3,000 IGF-IR sites/cell. In vivo, cixutumumab treatment delayed growth of H226 mesothelioma tumor xenografts in mice and improved the overall survival of these mice compared to mice treated with saline (p < 0.004). Our results demonstrate that the antitumor efficacy of cixutumumab including inhibition of IGF-IR downstream signaling is highly correlated with IGF-IR sites/cell. A phase II clinical trial of cixutumumab is currently ongoing for the treatment of patients with mesothelioma.


Subject(s)
Antibodies, Monoclonal/pharmacology , Mesothelioma/drug therapy , Receptor, IGF Type 1/metabolism , Animals , Antibodies, Monoclonal, Humanized , Binding Sites , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Insulin-Like Growth Factor I/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Mesothelioma/immunology , Mice , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , RNA Interference , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Small Interfering , Receptor, IGF Type 1/antagonists & inhibitors , Receptor, IGF Type 1/genetics , Receptor, IGF Type 1/immunology , Transplantation, Heterologous , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
11.
Transl Oncol ; 21: 101440, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35523008

ABSTRACT

Mesothelin (MSLN) is overexpressed by many cancers, including pancreatic ductal adenocarcinoma (PDAC) and has consequently become a target for anti-cancer therapeutics. Mature, membrane bound MSLN is cleaved by proteases, releasing a shed form that transits to the circulation. Many patients with mesothelioma and ovarian cancer have abnormally high serum MSLN concentration. However, serum MSLN concentration in PDAC patients rarely exceeds levels of healthy controls. Here, serum MSLN concentration in advanced PDAC patients was examined pre- and post-treatment. Serum MSLN did not correlate with tumor MSLN expression, nor with changes in tumor burden as assessed by PDAC serum tumor marker CA19-9. Subsequently, tumor-bearing mouse models were used to investigate the fate of shed MSLN in PDAC versus a control cervical cancer model. Efficiency of MSLN secretion into the serum was cell-line dependent. Tumors from some PDAC lines had poor MSLN secretion efficiency although these lines had similar or higher MSLN shedding rate, total and surface MSLN expression. Measurements of compartment-specific MSLN concentration taken at equilibrium suggested that tumors with poor MSLN secretion efficiency trapped shed MSLN in the tumor microenvironment (TME), a finding confirmed by dynamic experiments using a doxycycline-inducible MSLN expression system. Tumors with the poorest MSLN secretion efficiency had higher collagen density and increased abundance of MSLN binding partner MUC16. The tumor with the worst secretion efficiency could rebind shed MSLN to the cancer cell surface. Altogether, these data suggest that PDAC can trap shed MSLN within the TME. This finding has potential significance for design of MSLN-targeted therapeutics.

12.
Sci Rep ; 12(1): 2628, 2022 02 16.
Article in English | MEDLINE | ID: mdl-35173254

ABSTRACT

Several variants of SARS-CoV-2 have emerged. Those with mutations in the angiotensin-converting enzyme (ACE2) receptor binding domain (RBD) are associated with increased transmission and severity. In this study, we developed both antibody quantification and functional neutralization assays. Analyses of both COVID-19 convalescent and diagnostic cohorts strongly support the use of RBD antibody levels as an excellent surrogate to biochemical neutralization activities. Data further revealed that the samples from mRNA vaccinated individuals had a median of 17 times higher RBD antibody levels and a similar degree of increased neutralization activities against RBD-ACE2 binding than those from natural infections. Our data showed that N501Y RBD had fivefold higher ACE2 binding than the original variant. While some antisera from naturally infected subjects had substantially reduced neutralization ability against N501Y RBD, all blood samples from vaccinated individuals were highly effective in neutralizing it. Thus, our data indicates that mRNA vaccination may generate more neutralizing RBD antibodies than natural immunity. It further suggests a potential need to maintain high RBD antibody levels to control the more infectious SARS-CoV-2 variants.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/metabolism , mRNA Vaccines/immunology , Angiotensin-Converting Enzyme 2/metabolism , COVID-19/virology , Humans , Neutralization Tests , SARS-CoV-2/metabolism
13.
Clin Cancer Res ; 28(7): 1353-1362, 2022 04 01.
Article in English | MEDLINE | ID: mdl-35031545

ABSTRACT

PURPOSE: This study investigated the efficacy and tolerability of cabozantinib plus nivolumab (CaboNivo) in patients with metastatic urothelial carcinoma (mUC) that progressed on checkpoint inhibition (CPI). PATIENTS AND METHODS: A phase I expansion cohort of patients with mUC who received prior CPI was treated with cabozantinib 40 mg/day and nivolumab 3 mg/kg every 2 weeks until disease progression/unacceptable toxicity. The primary goal was objective response rate (ORR) per RECIST v.1.1. Secondary objectives included progression-free survival (PFS), duration of response (DoR), overall survival (OS), safety, and tolerability. RESULTS: Twenty-nine out of 30 patients enrolled were evaluable for efficacy. Median follow-up was 22.2 months. Most patients (86.7%) received prior chemotherapy and all patients received prior CPI (median seven cycles). ORR was 16.0%, with one complete response and three partial responses (PR). Among 4 responders, 2 were primary refractory, 1 had a PR, and 1 had stable disease on prior CPI. Median DoR was 33.5 months [95% confidence interval (CI), 3.7-33.5], median PFS was 3.6 months (95% CI, 2.1-5.5), and median OS was 10.4 months (95% CI, 5.8-19.5). CaboNivo decreased immunosuppressive subsets such as regulatory T cells (Tregs) and increased potential antitumor immune subsets such as nonclassical monocytes and effector T cells. A lower percentage of monocytic myeloid-derived suppressor cells (M-MDSC) and polymorphonuclear MDSCs, lower CTLA-4 and TIM-3 expression on Tregs, and higher effector CD4+ T cells at baseline were associated with better PFS and/or OS. CONCLUSIONS: CaboNivo was clinically active, well tolerated, and favorably modulated peripheral blood immune subsets in patients with mUC refractory to CPI.


Subject(s)
Carcinoma, Transitional Cell , Urinary Bladder Neoplasms , Anilides , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Carcinoma, Transitional Cell/drug therapy , Humans , Immune Checkpoint Inhibitors , Nivolumab , Pyridines , Urinary Bladder Neoplasms/drug therapy
14.
Physiol Meas ; 42(8)2021 08 27.
Article in English | MEDLINE | ID: mdl-34315149

ABSTRACT

Objective. Sleep apnea (SA) is a chronic condition that fragments sleep and results in intermittent hypoxemia, which in long run leads to cardiovascular diseases like stroke. Diagnosis of SA through polysomnography is costly, inconvenient, and has long waiting list. Wearable devices provide a low-cost solution to the ambulatory detection of SA syndrome for undiagnosed patients. One of the wearables are the ones based on minute-by-minute analysis of single-lead electrocardiogram (ECG) signal. Processing ECG segments online at wearables contributes to memory conservation and privacy protection in long-term SA monitoring, and light-weight models are required due to stringent computation resource.Approach.We propose fast apnea syndrome screening neural network (FASSNet), an effective end-to-end neural network to perform minute-apnea event detection. Low-frequency components of filtered ECG spectrogram are selected as input. The model initially processes the spectrogram via convolution blocks. Bidirectional long-short-term memory blocks are used along the frequency axis to complement position information of frequency bands. Layer normalisation is implemented to retain in-epoch information since apnea periods have variable lengths. Experiments were carried out on 70 recordings of Apnea-ECG database, where each 60 s ECG segment is manually labelled as an apnea or normal minute by technician. Both ten-fold and patient-agnostic validation protocols are adopted.Main results.FASSNet is light-weighted, since its value of model parameters and multiply accumulates are 0.06% and 28.33% of those of an AlexNet benchmark, respectively. Meanwhile, FASSNet achieves an accuracy of 87.09%, a sensitivity of 77.96%, a specificity of 91.74%, and an F1 score of 81.61% in apnea event detection. Its accuracy of diagnosing SA syndrome severity exceeds 90% under the patient-agnostic protocol.Significance:FASSNet is a computationally efficient and accurate neural network for wearables to detect SA events and estimate SA severity based on minute-level diagnosis.


Subject(s)
Sleep Apnea Syndromes , Wearable Electronic Devices , Electrocardiography , Humans , Neural Networks, Computer , Polysomnography , Sleep Apnea Syndromes/diagnosis
15.
ACS Appl Mater Interfaces ; 13(41): 48934-48948, 2021 Oct 20.
Article in English | MEDLINE | ID: mdl-34615351

ABSTRACT

Propane nonoxidative dehydrogenation (PDH) is a promising route to produce propylene with the development of shale gas exploration technology. Co-based catalysts with low cost and low toxicity could activate C-H effectively, but they suffer from deactivation with coke formation. In this work, a catalyst formed by incorporating highly dispersed Co sites into a Silicalite-1 zeolite framework (Co-Silicalite-1) is synthesized by a hydrothermal protocol in the presence of ammonia, which exhibits superior propane dehydrogenation catalytic performance with 0.0946 mmol C3H6·s-1·gCo-1 and propylene selectivity higher than 98.5%. It also shows outstanding catalytic stability and coking resistance in a 3560 min time-on-stream. Combined characterization results demonstrate that the tetrahedrally coordinated Co2+ site serves as the PDH catalytic active site, which is stabilized by Si-O units of the zeolite framework. Incorporation of Co sites into the zeolite framework could avoid the reduction of Co species to metallic Co. Moreover, the catalytic performance is improved by the enhanced propane adsorption and propylene desorption.

16.
Bone Marrow Transplant ; 56(12): 2934-2939, 2021 12.
Article in English | MEDLINE | ID: mdl-34433916

ABSTRACT

Limited information is available regarding clinical and biological properties of fatigue in patients with chronic graft-versus-host disease (cGvHD). Patients with moderate-to-severe cGvHD per NIH criteria were enrolled on a cross-sectional study and categorized as "fatigued" if SF-36 vitality score was <40. Clinical and laboratory parameters of fatigued (n = 109) and nonfatigued patients (n = 72) were compared. In univariate analysis, walk velocity, NIH joint-fascia score, human activity profile, and SF-36 physical and mental health self-report scales were correlates of fatigue. No cGvHD biomarkers were associated with fatigue. NIH joint score, Lee sleep and depression questions, and PG-SGA activities and function score jointly predicted fatigue. Though higher rates of depression and insomnia were reported in the fatigued group, antidepressant or sleep aid use did not differ between groups. Survival ratio was not significantly different by fatigue status. Pathophysiology of fatigue in patients with cGvHD is complex and may involve mechanisms unrelated to disease activity. Patients with cGvHD experiencing fatigue had higher rates of untreated depression and insomnia, highlighting the need to focus clinical management of these conditions to improve health-related quality of life.


Subject(s)
Graft vs Host Disease , Hematologic Neoplasms , Chronic Disease , Cross-Sectional Studies , Cytokines , Fatigue/etiology , Graft vs Host Disease/etiology , Graft vs Host Disease/pathology , Hematologic Neoplasms/complications , Hematologic Neoplasms/pathology , Hematologic Neoplasms/therapy , Humans , Quality of Life
17.
J Virol ; 82(17): 8656-63, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18562529

ABSTRACT

Human immunodeficiency virus (HIV) virion infectivity factor (Vif) causes the proteasome-mediated destruction of human antiviral protein APOBEC3G by tethering it to a cellular E3 ubiquitin ligase composed of ElonginB, ElonginC, Cullin5, and Rbx2. It has been proposed that HIV Vif hijacks the E3 ligase through two regions within its C-terminal domain: a BC box region that interacts with ElonginC and a novel zinc finger motif that interacts with Cullin5. We have determined the crystal structure of the HIV Vif BC box in complex with human ElonginB and ElonginC. This complex presents direct structural evidence of the recruitment of a human ubiquitin ligase by a viral BC box protein that mimics the conserved interactions of cellular ubiquitin ligases. We further mutated conserved hydrophobic residues in a region downstream of the Vif BC box. These mutations demonstrate that this region, the Vif Cullin box, composes a third E3-ligase recruiting site critical for interaction between Vif and Cullin5. Furthermore, our homology modeling reveals that the Vif Cullin box and zinc finger motif may be positioned adjacent to the N terminus of Cullin5 for interaction with loop regions in the first cullin repeat of Cullin5.


Subject(s)
Gene Products, vif/chemistry , Gene Products, vif/metabolism , HIV/genetics , Alanine/metabolism , Amino Acid Sequence , Amino Acid Substitution , Cell Line , Consensus Sequence , Conserved Sequence , Crystallization , Cullin Proteins/chemistry , Cullin Proteins/metabolism , Escherichia coli/genetics , Gene Products, vif/genetics , Humans , Hydrophobic and Hydrophilic Interactions , Kidney/cytology , Models, Biological , Models, Molecular , Molecular Sequence Data , Mutation , Plasmids , Protein Binding , Protein Structure, Secondary , Protein Structure, Tertiary , Sequence Homology, Amino Acid , Transfection , Ubiquitin-Protein Ligases/chemistry , Ubiquitin-Protein Ligases/metabolism , X-Ray Diffraction
18.
Clin Cancer Res ; 14(1): 209-14, 2008 Jan 01.
Article in English | MEDLINE | ID: mdl-18172272

ABSTRACT

PURPOSE: To determine if sorafenib is associated with a 4-month probability of progression-free survival, which is consistent with 50%, as determined by clinical, radiographic, and prostate-specific antigen (PSA) criteria in patients with metastatic androgen-independent prostate cancer (AIPC). EXPERIMENTAL DESIGN: Patients with progressive metastatic AIPC were enrolled in an open-label, single-arm phase II study. Sorafenib was given continuously at a dose of 400 mg orally twice daily in 28-day cycles. Clinical assessment and PSA measurement were done every cycle whereas radiographic measurements were carried out every two cycles. RESULTS: Twenty-two patients were enrolled in the study to date, completing a planned first stage of the trial. Baseline patient characteristics included a median age of 63.9 years (range, 50-77 years), Gleason score of 9 (range, 4-9.5), and PSA concentration of 53.3 ng/mL (range, 2-1,905 ng/mL). Fifty-nine percent of patients had received one prior chemotherapy regimen. Of the 21 patients with progressive disease, 13 progressed only by PSA criteria in the absence of evidence of clinical and radiographic progression. Two patients were found to have dramatic reduction of bone metastatic lesions as shown by bone scan, although they met PSA progression criteria at the time when scans were obtained. Toxicities likely related to treatment included one grade 3 hypertension; one grade 3 hand-foot syndrome; and grade 1/2 toxicities: fatigue, anorexia, hypertension, skin rash, nausea, and diarrhea. Results from in vitro studies suggested that PSA is not a good marker of sorafenib activity. The geometric mean exposure (AUC(0-12)) and maximum concentration (C(max)) were 9.76 h mg/L and 1.28 mg/L, respectively. The time to maximum concentration (t(max)) and accumulation ratio (after second dose) ranged from 2 to 12 h and 0.68 to 6.43, respectively. CONCLUSIONS: Sorafenib is relatively well tolerated in AIPC with two patients showing evidence of improved bony metastatic lesions. Interpretation of this study is complicated by discordant radiographic and PSA responses. PSA may not be an adequate biomarker for monitoring sorafenib activity. Based on these observations, further investigation using only clinical and radiographic end points as progression criteria is warranted. Accrual to the second stage of trial is ongoing.


Subject(s)
Antineoplastic Agents/therapeutic use , Benzenesulfonates/therapeutic use , Prostatic Neoplasms/drug therapy , Pyridines/therapeutic use , Aged , Antineoplastic Agents/pharmacokinetics , Benzenesulfonates/pharmacokinetics , Disease-Free Survival , Extracellular Signal-Regulated MAP Kinases/drug effects , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Niacinamide/analogs & derivatives , Phenylurea Compounds , Prostate-Specific Antigen/blood , Prostate-Specific Antigen/drug effects , Prostatic Neoplasms/blood , Prostatic Neoplasms/mortality , Pyridines/pharmacokinetics , Sorafenib , Survival Analysis , Treatment Outcome
19.
Cancer Epidemiol Biomarkers Prev ; 28(1): 110-118, 2019 01.
Article in English | MEDLINE | ID: mdl-30297515

ABSTRACT

BACKGROUND: Previously, we observed a strong relationship between circulating serum inflammation proteins in relation to lung cancer diagnosis and risk, both in case-control and prospective cohorts. Low-dose computed tomography (LDCT) screening has a high prevalence of false-positive nodules, thus companion noninvasive biomarkers that can distinguish between benign and malignant nodules could have clinical utility and positive impact on patient outcomes. METHODS: We conducted a nested case-control study within the National Lung Screening Trial. Concentrations of 30 inflammation proteins were measured on plasma samples of 262 cases and 528 controls using a highly sensitive and analytically validated electrochemiluminescence V-PLEX immunoassay. RESULTS: Comparing the fourth quartile with the first quartile, we found increased IFNγ and IL12/IL23p40 associated with increased odds of a lung cancer diagnosis [OR 1.89, 95% confidence intervals (CI), 1.16-3.09; OR 2.49, 95% CI, 1.46-4.23, respectively]. Confirming our previous observations, we also detected a relationship between increased IL6, IL8, and C-reactive protein (CRP) with lung cancer diagnosis. These relationships were significant after adjustment for age, gender, race, smoking, body mass index (BMI), family history of lung cancer, and previous diagnoses of inflammatory conditions. However, none of these proteins could distinguish between a benign and malignant lung nodule (IL6: OR 1.25, 95% CI, 0.59-2.64; IL8: OR 1.40, 95% CI, 0.70-2.81; CRP: OR 0.98, 95% CI, 0.45-2.12). CONCLUSIONS: We have discovered new associations for IFNγ and IL12/IL23p40 with lung cancer but have no evidence that these proteins can distinguish between benign and malignant lung nodules. IMPACT: Circulating inflammation proteins are unlikely to have utility as companion LDCT biomarkers.


Subject(s)
C-Reactive Protein/analysis , Cytokines/blood , Inflammation , Lung Neoplasms/blood , Aged , Biomarkers, Tumor/blood , Case-Control Studies , Female , Humans , Lung Neoplasms/diagnosis , Male , Middle Aged , Random Allocation
20.
J Thorac Oncol ; 14(7): 1192-1203, 2019 07.
Article in English | MEDLINE | ID: mdl-30953795

ABSTRACT

INTRODUCTION: Lung cancer incidence is higher among African Americans (AAs) compared with European Americans (EAs) in the United States. We and others have previously shown a relationship between immune and inflammation proteins with lung cancer in EAs. Our aim was to investigate the etiologic relationship between inflammation and lung cancer in AAs. METHODS: We adopted a two-stage, independent study design (discovery cases, n = 316; control cases, n = 509) (validation cases, n = 399; control cases, n = 400 controls) and measured 30 inflammation proteins in blood using Meso Scale Discovery V- PLEX multiplex assays. RESULTS: We identified and validated 10 proteins associated with lung cancer in AAS, some that were common between EAs and AAs (C-reactive proteins [OR: 2.90; 95% confidence interval (CI): 1.99-4.22], interferon γ [OR: 1.55; 95% CI: 1.10-2.19], interleukin 6 [OR: 6.28; 95% CI: 4.10-9.63], interleukin 8 [OR: 2.76; 95% CI: 1.92-3.98]) and some that are only observed among AAs (interleukin 10 [OR: 1.69; 95% CI: 1.20-2.38], interleukin 15 [OR: 2.83; 95% CI: 1.96-4.07], interferon gamma-induced protein 10 [OR: 1.54; 95% CI: 1.09-2.18], monocyte chemotactic protein-4 [OR: 0.54; 95% CI: 0.38-0.76], macrophage inflammatory protein-1 alpha [OR: 1.57; 95% CI: 1.12-2.21], and tumor necrosis factor ß [OR: 0.52; 95% CI: 0.37-0.74]). We did not find evidence that either menthol cigarette smoking or global genetic ancestry drove these population differences. CONCLUSIONS: Our results highlight a distinct inflammation profile associated with lung cancer in AAs compared with EAs. These data provide new insight into the etiology of lung cancer in AAs. Further work is needed to understand what drives this relationship with lung cancer and whether these proteins have utility in the setting of early diagnosis.


Subject(s)
Biomarkers/blood , Black or African American/statistics & numerical data , Inflammation Mediators/blood , Inflammation/complications , Lung Neoplasms/blood , White People/statistics & numerical data , Adult , Aged , Aged, 80 and over , Case-Control Studies , Female , Follow-Up Studies , Humans , Lung Neoplasms/etiology , Lung Neoplasms/pathology , Male , Middle Aged , Prognosis , Survival Rate , Young Adult
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