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1.
J Acoust Soc Am ; 155(3): 1813-1824, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38445988

RESUMO

This study assessed whether the effects of contralateral acoustic stimulation (CAS) are consistent with eliciting the medial olivocochlear (MOC) reflex for measurements sensitive to outer hair cell (otoacoustic emissions, OAEs), auditory-nerve (AN; compound action potential, CAP), and brainstem/cortical (envelope-following response, EFR) function. The effects of CAS were evaluated for simultaneous measurement of OAEs, CAPs, and EFRs in participants with normal hearing. Clicks were presented at 40 or 98 Hz in three ipsilateral noise conditions (no noise, 45 dB SPL, and 55 dB SPL). For the no noise condition, CAS suppressed or enhanced EFR amplitudes for 40- and 98-Hz clicks, respectively, while CAS had no significant effect on CAP amplitudes. A follow-up experiment using slower rates (4.4-22.2 Hz) assessed whether this insignificant CAS effect on CAPs was from ipsilateral MOC stimulation or AN adaptation; however, CAS effects remained insignificant despite favorable signal-to-noise ratios. CAS-related enhancements of EFR and CAP amplitudes in ipsilateral noise were not observed, contrary to the anti-masking effect of the MOC reflex. EFR and OAE suppression from CAS were not significantly correlated. Thus, the effects of CAS on EFRs may not be solely mediated by the MOC reflex and may be partially mediated by higher auditory centers.


Assuntos
Potenciais Evocados , Emissões Otoacústicas Espontâneas , Humanos , Potenciais de Ação , Estimulação Acústica , Reflexo
2.
Cancer Discov ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319303

RESUMO

Adding anti-PD1 to 5-FU/platinum improves survival in some advanced gastroesophageal adenocarcinomas (GEA). To understand the effects of chemotherapy and immunotherapy we conducted a phase II frontline trial (n = 47) sequentially adding pembrolizumab to 5-FU/platinum in advanced GEA. Using serial biopsy of the primary tumor at baseline, after one cycle of 5-FU/platinum, and after the addition of pembrolizumab we transcriptionally profiled 358,067 single cells to identify evolving multicellular TME networks. Chemotherapy induced early on-treatment multicellular hubs with tumor-reactive T-cell and M1-like macrophage interactions in slow progressors. Faster progression featured increased MUC5A and MSLN containing treatment-resistance programs in tumor cells and M2-like macrophages with immunosuppressive stromal interactions. After pembrolizumab we observed increased CD8 T-cell infiltration and development of an immunity hub involving tumor-reactive CXCL13 T-cell program and epithelial interferon-stimulated gene programs. Strategies to drive increases in anti-tumor immune hub formation could expand the portion of patients benefiting from anti-PD1 approaches.

3.
Space Sci Rev ; 219(6): 46, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37636325

RESUMO

The Galileo mission to Jupiter revealed that Europa is an ocean world. The Galileo magnetometer experiment in particular provided strong evidence for a salty subsurface ocean beneath the ice shell, likely in contact with the rocky core. Within the ice shell and ocean, a number of tectonic and geodynamic processes may operate today or have operated at some point in the past, including solid ice convection, diapirism, subsumption, and interstitial lake formation. The science objectives of the Europa Clipper mission include the characterization of Europa's interior; confirmation of the presence of a subsurface ocean; identification of constraints on the depth to this ocean, and on its salinity and thickness; and determination of processes of material exchange between the surface, ice shell, and ocean. Three broad categories of investigation are planned to interrogate different aspects of the subsurface structure and properties of the ice shell and ocean: magnetic induction, subsurface radar sounding, and tidal deformation. These investigations are supplemented by several auxiliary measurements. Alone, each of these investigations will reveal unique information. Together, the synergy between these investigations will expose the secrets of the Europan interior in unprecedented detail, an essential step in evaluating the habitability of this ocean world.

4.
J Plast Reconstr Aesthet Surg ; 82: 176-185, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37186973

RESUMO

BACKGROUND: Common mental disorders (CMD) are highly morbid conditions not routinely screened for in chronic wound care. A comorbid psychiatric condition's influence on a patient with chronic wounds' quality of life (QoL) is unknown. This study investigates the implications of CMD on QoL in patients with chronic lower extremity (LE) wounds. METHODS: This cross-sectional study surveyed patients with chronic LE wounds evaluated in our multidisciplinary clinic between June-July 2022. Surveys included validated physical and social QoL questionnaires, including the Lower Extremity Functional Scale (LEFS), Patient-Reported Outcomes Measurement Information System (PROMIS-3a) Scale v2.0, 12-Item Short-Form (SF-12), and a screening tool for common mental disorders, the Self-Reporting Questionnaire 20 (SRQ-20). Data regarding patient demographics, comorbidities, psychiatric diagnoses, and wound care history were retrospectively collected. RESULTS: Of the 265 identified patients, 39 (14.7%) had documented psychiatric diagnoses, most often depression or anxiety. The diagnosed cohort had higher median SRQ-20 scores (6, IQR: 6 vs. 3, IQR: 5; P < 0.001) and a higher proportion of positive screens for CMD (30.8% vs. 15.5%; P = 0.020) than non-diagnosed patients. There were no differences in physical or social QoL in patients with and without a psychiatric diagnosis. However, individuals screening positively for CMD experienced significantly more pain (T-score 60.2 vs. 51.4, P = 0.0052) and reduced function (LEFS 26.0 vs. 41.0, P < 0.0000). CONCLUSION: This study illustrates that patients with chronic LE wounds experience potentially meaningful psychologic distress. Further, symptoms of a CMD (SRQ-20 ≥8), rather than a previous diagnosis, may influence pain and functional outcomes. These findings emphasize the potential relevance of psychological distress in this population and reinforce the need for further investigation of actionable responses to this apparent need.


Assuntos
Transtornos Mentais , Qualidade de Vida , Humanos , Estudos Transversais , Estudos Retrospectivos , Transtornos Mentais/complicações , Transtornos Mentais/epidemiologia , Inquéritos e Questionários , Dor
5.
Space Sci Rev ; 219(3): 22, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37007705

RESUMO

The objective of the Psyche Magnetometry Investigation is to test the hypothesis that asteroid (16) Psyche formed from the core of a differentiated planetesimal. To address this, the Psyche Magnetometer will measure the magnetic field around the asteroid to search for evidence of remanent magnetization. Paleomagnetic measurements of meteorites and dynamo theory indicate that a diversity of planetesimals once generated dynamo magnetic fields in their metallic cores. Likewise, the detection of a strong magnetic moment ( > 2 × 10 14 Am 2 ) at Psyche would likely indicate that the body once generated a core dynamo, implying that it formed by igneous differentiation. The Psyche Magnetometer consists of two three-axis fluxgate Sensor Units (SUs) mounted 0.7 m apart along a 2.15-m long boom and connected to two Electronics Units (EUs) located within the spacecraft bus. The Magnetometer samples at up to 50 Hz, has a range of ± 80 , 000 nT , and an instrument noise of 39 pT axis - 1 3 σ integrated over 0.1 to 1 Hz. The two pairs of SUs and EUs provide redundancy and enable gradiometry measurements to suppress noise from flight system magnetic fields. The Magnetometer will be powered on soon after launch and acquire data for the full duration of the mission. The ground data system processes the Magnetometer measurements to obtain an estimate of Psyche's dipole moment.

6.
Ann Surg ; 278(2): 153-158, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37066793

RESUMO

OBJECTIVE: We sought to perform a large-scale systematic review across all sham-controlled studies currently present in the literature to better characterize the ethical considerations of these studies. BACKGROUND: Innovative surgical procedures are often introduced into the clinical setting without the robust clinical trials required for medicinal treatments. Sham surgeries serve as placebos by performing all steps of a surgical intervention aside from those deemed therapeutically necessary. Yet, sham trials are underutilized because of ethical controversy. METHODS: Ovid MEDLINE was queried through April 2022 with combinations of the Medical Subject (MeSH) headings and keywords including, but not limited to, "surgery," "endoscopy," "randomized controlled trial," and "sham procedure." Primary outcomes were surgical indications and characteristics, outcome measurements, and whether the investigational treatment was offered to the sham cohort. RESULTS: One hundred seventy-two articles fit our inclusion criteria, with gastrointestinal pathologies being the most common surgical indication. Participants, personnel, and outcome assessment were all blinded in 8.7% of trials (n=15). Study populations included adult subjects (age ≥18) in 170 studies (98.8%), and two involved children. The most common level of dissection and type of anesthesia were deep (n=66, 38.4%) and general (n=49, 28.5%), respectively. An open surgical approach was utilized in 20.9% of studies (n=36). Primary outcomes were objective in 75 studies (43.6%) and subjective in 97 (56.4%), 62 of which used validated outcome measures (36.0%). Four trials explicitly did not offer the surgery to the sham arm (2.3%), whereas 106 had no mention of whether the intervention was offered (61.6%). CONCLUSIONS: Our systematic review of 172 randomized, sham-controlled trials highlights the ethical considerations that must be considered in these studies, namely the importance of transparent study design and objective outcome reporting, the difficulty of informed consent, and the inherent risks associated with surgical interventions.


Assuntos
Endoscopia , Projetos de Pesquisa , Adulto , Criança , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
bioRxiv ; 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36945655

RESUMO

Bacterial populations that originate from a single bacterium are not strictly clonal. Often, they contain subgroups with distinct phenotypes. Bacteria can generate heterogeneity through phase variation: a preprogrammed, reversible mechanism that alters gene expression levels across a population. One well studied type of phase variation involves enzyme-mediated inversion of specific intergenic regions of genomic DNA. Frequently, these DNA inversions flip the orientation of promoters, turning ON or OFF adjacent coding regions within otherwise isogenic populations. Through this mechanism, inversion can affect fitness, survival, or group dynamics. Here, we develop and apply bioinformatic approaches to discover thousands of previously undescribed phase-variable regions in prokaryotes using long-read datasets. We identify 'intragenic invertons', a surprising new class of invertible elements found entirely within genes, in bacteria and archaea. To date, inversions within single genes have not been described. Intragenic invertons allow a gene to encode two or more versions of a protein by flipping a DNA sequence within the coding region, thereby increasing coding capacity without increasing genome size. We experimentally characterize specific intragenic invertons in the gut commensal Bacteroides thetaiotaomicron, presenting a 'roadmap' for investigating this new gene-diversifying phenomenon.

8.
Acad Radiol ; 30(8): 1721-1726, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36184379

RESUMO

OBJECTIVES: The aim of this exploratory preclinical study was to evaluate the efficacy of 18F-FMAU PET in quantitatively measuring cellular proliferation changes in response to a chemotherapeutic agent in experimental prostate cancer models. METHODS AND MATERIALS: Docetaxel (DTX) ‒ a standard therapy agent in castrate-resistant metastatic prostate cancer was used as the chemotherapy drug. Athymic male nu/nu mice were inoculated with PC-3 cells in the right flank. After the tumor diameter reached 5 mm, DTX (24 mg/kg) was injected intravenously twice a week, whereas the control group was intravenously administered with saline. The tumor size and body weight were monitored, and longitudinal PET scans were acquired with 18F-FMAU to evaluate tumor cellular proliferation. 18F-FMAU PET scans were performed at 2 hours post-injection of 18F-FMAU on days 0, 11, 18, and 22. Biodistribution studies were carried out after the PET scan on day 22. RESULTS: Consecutive administrations of DTX were effective in inhibiting PC-3 tumor growth compared to the control group. For PET imaging, PC-3 tumor uptake of 18F-FMAU in the DTX group was increased significantly from 3.09 ± 0.60 %ID/g (day 0) to 5.32 ± 0.37 %ID/g (day 22), whereas the 18F-FMAU tumor update in the control group remained relatively stable on day 0 (2.37 ± 0.51 %ID/g) vs. day 22 (1.83 ± 0.22 %ID/g). The tumor-to-muscle uptake ratio of 18F-FMAU was increased from 2.63 ± 0.20 (day 0) to 5.91 ± 1.1 (day 22) in the DTX group. On day 22, no statistical significance was observed in the tumor-to-muscle uptake ratio of 18F-FMAU in the DTX group vs. the control group. The tumor-to-liver uptake ratio of 18F-FMAU was also similar on day 22 in the DTX group (4.29 ± 0.09) vs. the control group (3.83 ± 0.59). CONCLUSION: 18F-FMAU uptake in implanted PC-3 tumors increases with DTX despite inhibiting tumor growth. Further investigation is needed to decipher the underlying biological mechanism of this apparent flare effect and its relation to the predictability of tumor response to DTX.


Assuntos
Neoplasias da Próstata , Humanos , Masculino , Animais , Camundongos , Docetaxel/uso terapêutico , Docetaxel/farmacologia , Distribuição Tecidual , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Tomografia por Emissão de Pósitrons , Proliferação de Células , Linhagem Celular Tumoral
9.
Pharmaceuticals (Basel) ; 15(9)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36145258

RESUMO

It is estimated that hearing loss currently affects more than 1.5 billion people, or approximately 20% of the global population; however, presently, there are no Food and Drug Administration-approved therapeutics or prophylactics for this condition. While continued research on the development of otoprotective drugs to target this clear unmet need is an obvious path, there are numerous challenges to translating promising therapeutic candidates into human clinical testing. The screening of promising drug candidates relies exclusively on preclinical models. Current models do not permit the rapid high-throughput screening of promising drug candidates, and their relevance to clinical scenarios is often ambiguous. With the current study, we seek to understand the drug permeability properties of the cadaveric tympanic and round window membranes with the goal of generating knowledge that could inform the design and/or evaluation of in vitro organotypic models. The development of such models could enable the early high-throughput screening of topical therapeutic candidates and should address some of the limitations of currently used animal models.

10.
Nat Commun ; 13(1): 4632, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36042221

RESUMO

The Juno spacecraft has been collecting data to shed light on the planet's origin and characterize its interior structure. The onboard gravity science experiment based on X-band and Ka-band dual-frequency Doppler tracking precisely measured Jupiter's zonal gravitational field. Here, we analyze 22 Juno's gravity passes to investigate the gravity field. Our analysis provides evidence of new gravity field features, which perturb its otherwise axially symmetric structure with a time-variable component. We show that normal modes of the planet could explain the anomalous signatures present in the Doppler data better than other alternative explanations, such as localized density anomalies and non-axisymmetric components of the static gravity field. We explain Juno data by p-modes having an amplitude spectrum with a peak radial velocity of 10-50 cm/s at 900-1200 µHz (compatible with ground-based observations) and provide upper bounds on lower frequency f-modes (radial velocity smaller than 1 cm/s). The new Juno results could open the possibility of exploring the interior structure of the gas giants through measurements of the time-variable gravity or with onboard instrumentation devoted to the observation of normal modes, which could drive spacecraft operations of future missions.

11.
Med ; 3(6): 371-387.e9, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35434682

RESUMO

Background: COVID-19 manifests with respiratory, systemic, and gastrointestinal (GI) symptoms.1, SARS-CoV-2 RNA is detected in respiratory and fecal samples, and recent reports demonstrate viral replication in both the lung and intestinal tissue.2, 3, 4 Although much is known about early fecal RNA shedding, little is known about long-term shedding, especially in those with mild COVID-19. Furthermore, most reports of fecal RNA shedding do not correlate these findings with GI symptoms.5. Methods: We analyzed the dynamics of fecal RNA shedding up to 10 months after COVID-19 diagnosis in 113 individuals with mild to moderate disease. We also correlated shedding with disease symptoms. Findings: Fecal SARS-CoV-2 RNA is detected in 49.2% [95% confidence interval, 38.2%-60.3%] of participants within the first week after diagnosis. Whereas there was no ongoing oropharyngeal SARS-CoV-2 RNA shedding in subjects at 4 months, 12.7% [8.5%-18.4%] of participants continued to shed SARS-CoV-2 RNA in the feces at 4 months after diagnosis and 3.8% [2.0%-7.3%] shed at 7 months. Finally, we found that GI symptoms (abdominal pain, nausea, vomiting) are associated with fecal shedding of SARS-CoV-2 RNA. Conclusions: The extended presence of viral RNA in feces, but not in respiratory samples, along with the association of fecal viral RNA shedding with GI symptoms suggest that SARS-CoV-2 infects the GI tract and that this infection can be prolonged in a subset of individuals with COVID-19. Funding: This research was supported by a Stanford ChemH-IMA grant; fellowships from the AACR and NSF; and NIH R01-AI148623, R01-AI143757, and UL1TR003142.


Assuntos
COVID-19 , Doenças Transmissíveis , Gastroenteropatias , COVID-19/diagnóstico , Teste para COVID-19 , Fezes , Gastroenteropatias/diagnóstico , Humanos , Pulmão , RNA Viral/genética , SARS-CoV-2/genética
12.
Space Sci Rev ; 218(3): 17, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35431348

RESUMO

The asteroid (16) Psyche may be the metal-rich remnant of a differentiated planetesimal, or it may be a highly reduced, metal-rich asteroidal material that never differentiated. The NASA Psyche mission aims to determine Psyche's provenance. Here we describe the possible solar system regions of origin for Psyche, prior to its likely implantation into the asteroid belt, the physical and chemical processes that can enrich metal in an asteroid, and possible meteoritic analogs. The spacecraft payload is designed to be able to discriminate among possible formation theories. The project will determine Psyche's origin and formation by measuring any strong remanent magnetic fields, which would imply it was the core of a differentiated body; the scale of metal to silicate mixing will be determined by both the neutron spectrometers and the filtered images; the degree of disruption between metal and rock may be determined by the correlation of gravity with composition; some mineralogy (e.g., modeled silicate/metal ratio, and inferred existence of low-calcium pyroxene or olivine, for example) will be detected using filtered images; and the nickel content of Psyche's metal phase will be measured using the GRNS.

13.
J Scleroderma Relat Disord ; 7(1): 33-41, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35386940

RESUMO

Background: Immunosuppression remains the main treatment for progressing skin involvement, interstitial lung disease and inflammatory joint or muscle disease in systemic sclerosis. This study investigated the pattern and trends in immunosuppressive agents used in early systemic sclerosis (diagnosed before and after 2007) to determine whether the changes in the preferred type, timing and combination of immunosuppression took place over the past decade. Methods: In total, 397 Canadian Scleroderma Research Group database patients (183 diffuse cutaneous systemic sclerosis and 214 limited cutaneous systemic sclerosis) who had baseline and follow-up visits within 3 years (mean: 1.8 ± 0.8) after disease onset were included: 82% females, age at diagnosis 53 ± 13 years. Bivariate, chi-square, analysis of variance and adjusted regression analyses were used. Results: In total, 115 diffuse cutaneous systemic sclerosis patients (63%) and 62 limited cutaneous systemic sclerosis (29%) received immunosuppressive drugs, most commonly methotrexate, followed by mycophenolate mofetil and cyclophosphamide. In diffuse cutaneous systemic sclerosis, immunosuppressants were prescribed after 2007 more often (74% vs 50%, p = 0.001), especially methotrexate (p = 0.02) and mycophenolate mofetil (p = 0.04), and earlier (peak at 2 years after onset). Immunosuppressive therapy was associated with male gender, interstitial lung disease, anti-Scl70 positivity, ACA negativity and inflammatory joint disease in limited cutaneous systemic sclerosis and with ACA negativity and a higher modified Rodnan skin score in diffuse cutaneous systemic sclerosis. Multivariate regression analysis showed that the use of immunosuppressants after 2007 was predicted only by ACA negativity in limited cutaneous systemic sclerosis and by younger age in diffuse cutaneous systemic sclerosis. Conclusion: Over the past decade, there has been a trend to prescribe immunosuppressants more often and earlier in diffuse cutaneous systemic sclerosis patients, regardless of modified Rodnan skin score. Methotrexate is being more frequently used, and mycophenolate mofetil has gained favour over cyclophosphamide. Autoantibody status was the most consistent predictor of immunosuppressive therapy.

14.
Cell ; 184(17): 4401-4413.e10, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34265281

RESUMO

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants that escape convalescent and vaccine-induced antibody responses has renewed focus on the development of broadly protective T-cell-based vaccines. Here, we apply structure-based network analysis and assessments of HLA class I peptide stability to define mutationally constrained CD8+ T cell epitopes across the SARS-CoV-2 proteome. Highly networked residues are conserved temporally among circulating variants and sarbecoviruses and disproportionately impair spike pseudotyped lentivirus infectivity when mutated. Evaluation of HLA class I stabilizing activity for 18 globally prevalent alleles identifies CD8+ T cell epitopes within highly networked regions with limited mutational frequencies in circulating SARS-CoV-2 variants and deep-sequenced primary isolates. Moreover, these epitopes elicit demonstrable CD8+ T cell reactivity in convalescent individuals but reduced recognition in recipients of mRNA-based vaccines. These data thereby elucidate key mutationally constrained regions and immunogenic epitopes in the SARS-CoV-2 proteome for a global T-cell-based vaccine against emerging variants and SARS-like coronaviruses.


Assuntos
Vacinas contra COVID-19/imunologia , Epitopos de Linfócito T , Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/química , Antígenos HLA/imunologia , Humanos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
15.
Cell Rep ; 36(2): 109378, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34260940

RESUMO

Defining factors that govern CD8+ T cell immunodominance is critical for the rational design of vaccines for viral pathogens. Here, we assess the contribution of human leukocyte antigen (HLA) class-I-peptide stability for 186 optimal HIV epitopes across 18 HLA alleles using transporter associated with antigen processing (TAP)-deficient mono-allelic HLA-expressing cell lines. We find that immunodominant HIV epitopes increase surface stabilization of HLA class-I molecules in comparison to subdominant epitopes. HLA class-I-peptide stability is also strongly correlated with overall immunodominance hierarchies, particularly for epitopes from high-abundance proteins (e.g., Gag). Moreover, HLA alleles associated with HIV protection are preferentially stabilized by epitopes derived from topologically important viral regions at a greater frequency than neutral and risk alleles. These findings indicate that relative stabilization of HLA class-I is a key factor for CD8+ T cell epitope immunodominance hierarchies, with implications for HIV control and the design of T-cell-based vaccines.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Epitopos Imunodominantes/imunologia , Peptídeos/imunologia , Alelos , Feminino , Células HEK293 , Humanos , Desnaturação Proteica , Estabilidade Proteica , Propriedades de Superfície
16.
Oncogene ; 40(20): 3624-3632, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33931739

RESUMO

Lung cancer is the leading cause of cancer mortality worldwide and KRAS is the most commonly mutated gene in lung adenocarcinoma (LUAD). The 78-kDa glucose-regulated protein GRP78/BiP is a key endoplasmic reticulum chaperone protein and a major pro-survival effector of the unfolded protein response (UPR). Analysis of the Cancer Genome Atlas database and immunostain of patient tissues revealed that compared to normal lung, GRP78 expression is generally elevated in human lung cancers, including tumors bearing the KRASG12D mutation. To test the requirement of GRP78 in human lung oncogenesis, we generated mouse models containing floxed Grp78 and Kras Lox-Stop-Lox G12D (KrasLSL-G12D) alleles. Simultaneous activation of the KrasG12D allele and knockout of the Grp78 alleles were achieved in the whole lung or selectively in lung alveolar epithelial type 2 cells known to be precursors for adenomas that progress to LUAD. Here we report that GRP78 haploinsufficiency is sufficient to suppress KrasG12D-mediated lung tumor progression and prolong survival. Furthermore, GRP78 knockdown in human lung cancer cell line A427 (KrasG12D/+) leads to activation of UPR and apoptotic markers and loss of cell viability. Our studies provide evidence that targeting GRP78 represents a novel therapeutic approach to suppress mutant KRAS-mediated lung tumorigenesis.


Assuntos
Chaperona BiP do Retículo Endoplasmático/metabolismo , Neoplasias Pulmonares/patologia , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Resposta a Proteínas não Dobradas , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Progressão da Doença , Chaperona BiP do Retículo Endoplasmático/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Transdução de Sinais
17.
Amino Acids ; 51(10-12): 1569-1575, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31621030

RESUMO

A novel recombinant disintegrin, vicrostatin (VCN), displays high binding affinity to a broad range of human integrins in substantial competitive biological advantage over other integrin-based antagonists. In this study, we synthesized a new 64Cu-labeled VCN probe and evaluated its imaging properties for prostate cancer in PC-3 tumor-bearing mice. Macrocyclic chelating agent 1,8-diamino-3,6,10,13,16,19-hexaazabicyclo[6.6.6]-eicosine (DiAmSar) was conjugated with PEG unit and followed by coupling with VCN. The precursor was then radiolabeled with positron emitter 64Cu (t1/2 = 12.7 h) in ammonium acetate buffer to provide 64Cu-Sar-PEG-VCN, which was subsequently subjected to in vitro studies, small animal PET, and biodistribution studies. The PC-3 tumor-targeting efficacy of 64Cu-Sar-PEG-VCN was compared to a cyclic RGD peptide-based PET probe (64Cu-Sar-RGD). 64Cu labeling was achieved in 75% decay-corrected yield with radiochemical purity of > 98%. The specific activity of 64Cu-Sar-PEG-VCN was estimated to be 37 MBq/nmol. MicroPET imaging results showed that 64Cu-Sar-PEG-VCN has preferential tumor uptake and good tumor retention in PC-3 tumor xenografts. As compared to 64Cu-Sar-RGD, 64Cu-Sar-PEG-VCN produces higher tumor-to-muscle (T/M) imaging contrast ratios at 2 h (4.66 ± 0.34 vs. 2.88 ± 0.46) and 24 h (4.98 ± 0.80 vs. 3.22 ± 0.30) post-injection (pi) and similar tumor-to-liver ratios at 2 h (0.43 ± 0.09 vs. 0.37 ± 0.04) and 24 h (0.57 ± 0.13 vs. 0.52 ± 0.07) pi. The biodistribution results were consistent with the quantitative analysis of microPET imaging, demonstrating good T/M ratio (2.73 ± 0.36) of 64Cu-Sar-PEG-VCN at 48 h pi in PC-3 tumor xenografts. For both microPET and biodistribution studies at 48 h pi, the PC-3 tumor uptake of 64Cu-Sar-PEG-VCN is lower than that of 64Cu-Sar-RGD. 64Cu-Sar-PEG-VCN has the potential for in vivo imaging of prostate cancer with PET, which may provide a unique non-invasive method to quantitatively localize and characterize prostate cancer.


Assuntos
Radioisótopos de Cobre/farmacocinética , Desintegrinas/farmacocinética , Tomografia por Emissão de Pósitrons/métodos , Neoplasias da Próstata/diagnóstico por imagem , Animais , Radioisótopos de Cobre/química , Desintegrinas/química , Avaliação Pré-Clínica de Medicamentos , Compostos Heterocíclicos/química , Humanos , Masculino , Camundongos , Camundongos Nus , Especificidade de Órgãos , Células PC-3 , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacocinética , Polietilenoglicóis/química , Neoplasias da Próstata/metabolismo , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Sarcosina/análogos & derivados , Sarcosina/química , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Gastroenterology ; 156(8): 2297-2312, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30836096

RESUMO

BACKGROUND & AIMS: Interleukin 6 (IL6) and tumor necrosis factor contribute to the development of colitis-associated cancer (CAC). We investigated these signaling pathways and the involvement of G protein subunit alpha i1 (GNAI1), GNAI2, and GNAI3 in the development of CAC in mice and humans. METHODS: B6;129 wild-type (control) or mice with disruption of Gnai1, Gnai2, and/or Gnai3 or conditional disruption of Gnai2 in CD11c+ or epithelial cells were given dextran sulfate sodium (DSS) to induce colitis followed by azoxymethane (AOM) to induce carcinogenesis; some mice were given an antibody against IL6. Feces were collected from mice, and the compositions of microbiomes were analyzed by polymerase chain reactions. Dendritic cells (DCs) and myeloid-derived suppressor cells (MDSCs) isolated from spleen and colon tissues were analyzed by flow cytometry. We performed immunoprecipitation and immunoblot analyses of colon tumor tissues, MDSCs, and mouse embryonic fibroblasts to study the expression levels of GNAI1, GNAI2, and GNAI3 and the interactions of GNAI1 and GNAI3 with proteins in the IL6 signaling pathway. We analyzed the expression of Gnai2 messenger RNA by CD11c+ cells in the colonic lamina propria by PrimeFlow, expression of IL6 in DCs by flow cytometry, and secretion of cytokines in sera and colon tissues by enzyme-linked immunosorbent assay. We obtained colon tumor and matched nontumor tissues from 83 patients with colorectal cancer having surgery in China and 35 patients with CAC in the United States. Mouse and human colon tissues were analyzed by histology, immunoblot, immunohistochemistry, and/or RNA-sequencing analyses. RESULTS: GNAI1 and GNAI3 (GNAI1;3) double-knockout (DKO) mice developed more severe colitis after administration of DSS and significantly more colonic tumors than control mice after administration of AOM plus DSS. Development of increased tumors in DKO mice was not associated with changes in fecal microbiomes but was associated with activation of nuclear factor (NF) κB and signal transducer and activator of transcription (STAT) 3; increased levels of GNAI2, nitric oxide synthase 2, and IL6; increased numbers of CD4+ DCs and MDSCs; and decreased numbers of CD8+ DCs. IL6 was mainly produced by CD4+/CD11b+, but not CD8+, DCs in DKO mice. Injection of DKO mice with a blocking antibody against IL6 reduced the expansion of MDSCs and the number of tumors that developed after CAC induction. Incubation of MDSCs or mouse embryonic fibroblasts with IL6 induced activation of either NF-κB by a JAK2-TRAF6-TAK1-CHUK/IKKB signaling pathway or STAT3 by JAK2. This activation resulted in expression of GNAI2, IL6 signal transducer (IL6ST, also called GP130) and nitric oxide synthase 2, and expansion of MDSCs; the expression levels of these proteins and expansion of MDSCs were further increased by the absence of GNAI1;3 in cells and mice. Conditional disruption of Gnai2 in CD11c+ cells of DKO mice prevented activation of NF-κB and STAT3 and changes in numbers of DCs and MDSCs. Colon tumor tissues from patients with CAC had reduced levels of GNAI1 and GNAI3 and increased levels of GNAI2 compared with normal tissues. Further analysis of a public human colorectal tumor DNA microarray database (GSE39582) showed that low Gani1 and Gnai3 messenger RNA expression and high Gnai2 messenger RNA expression were significantly associated with decreased relapse-free survival. CONCLUSIONS: GNAI1;3 suppresses DSS-plus-AOM-induced colon tumor development in mice, whereas expression of GNAI2 in CD11c+ cells and IL6 in CD4+/CD11b+ DCs appears to promote these effects. Strategies to induce GNAI1;3, or block GNAI2 and IL6, might be developed for the prevention or therapy of CAC in patients.


Assuntos
Transformação Celular Neoplásica/genética , Colite/patologia , Neoplasias do Colo/patologia , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Animais , Biópsia por Agulha , Carcinogênese , Colite/genética , Neoplasias do Colo/genética , Modelos Animais de Doenças , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Imuno-Histoquímica , Interleucina-16/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Distribuição Aleatória , Valores de Referência , Sensibilidade e Especificidade , Transdução de Sinais/genética
19.
Brief Funct Genomics ; 18(2): 133-139, 2019 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-30137232

RESUMO

Immune checkpoints have been the subject of a wave of new studies. Among these checkpoints are tytotoxic T-lymphocyte-associated antigen 4, checkpoints programmed death-1 and programmed death-ligand 1; their blockades have been approved by the Food and Drug Administration for therapy of melanoma and other types of cancers. Immunogenomics, which combines the latest nucleic acid sequencing strategy with immunotherapy, provides precise information about genomic alterations (e.g. mutations) and enables a paradigm shift of immune checkpoint therapy from tumor types to molecular signatures. Studying these critical checkpoints in relation to genomic mutations and neoantigens has produced groundbreaking results. This article examines these studies and delves into the relationships between immune checkpoint blockade and tumors harboring certain genomic mutations. Moreover, this article reviews recent studies on resistance to immune checkpoint therapy.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Genômica/métodos , Imunoterapia/métodos , Proteínas de Neoplasias/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Animais , Humanos , Proteínas de Neoplasias/genética , Neoplasias/genética , Neoplasias/imunologia
20.
Anticancer Res ; 37(2): 475-479, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28179292

RESUMO

AIM: We assessed the association between the presence and absence of androgen on the normal biodistribution of the positron emission tomography (PET) cellular proliferation imaging biomarker, [18F]-2'-Fluoro-5-methyl-1-beta-D-arabinofuranosyluracil (18F-FMAU), in mice. MATERIALS AND METHODS: Non-castrated (n=4) and castrated (n=4) athymic non-tumor-bearing male mice served as models for presence and absence, respectively, of androgen. MicroPET-CT scans were performed 1 h following tail vein administration of 200 uCi of 18F-FMAU. Imaging was performed at baseline and then at 7-day intervals longitudinally for 35 days only in castrated mice following subcutaneous introduction of a 12.5 mg, 21-day release, dihydrotestosterone pellet. Mean standardized uptake values (SUVmean) were obtained for liver, heart, and muscle. Several two-group comparisons of average of SUVmean were performed. RESULTS: Pre-pellet baseline average SUVmean (±s.d.) values in castrated mice were significantly lower than baseline non-castrated values, increased on day 15 and reached peak values on day 28, at which time they were significantly higher than corresponding baseline levels in both non-castrated and pre-pellet castrated mice. The peak values decreased significantly following dihydrotestosterone withdrawal. CONCLUSION: There is a significant modulatory effect of androgen on normal 18F-FMAU uptake levels in mice liver, heart and muscle tissues.


Assuntos
Androgênios/metabolismo , Arabinofuranosiluracila/análogos & derivados , Compostos Radiofarmacêuticos/farmacocinética , Animais , Arabinofuranosiluracila/farmacocinética , Preparações de Ação Retardada , Di-Hidrotestosterona/administração & dosagem , Radioisótopos de Flúor/análise , Masculino , Camundongos , Camundongos Nus , Orquiectomia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Distribuição Tecidual
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