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2.
Cell ; 171(7): 1559-1572.e20, 2017 Dec 14.
Article in English | MEDLINE | ID: mdl-29245011

ABSTRACT

Large-scale transcriptome sequencing efforts have vastly expanded the catalog of long non-coding RNAs (lncRNAs) with varying evolutionary conservation, lineage expression, and cancer specificity. Here, we functionally characterize a novel ultraconserved lncRNA, THOR (ENSG00000226856), which exhibits expression exclusively in testis and a broad range of human cancers. THOR knockdown and overexpression in multiple cell lines and animal models alters cell or tumor growth supporting an oncogenic role. We discovered a conserved interaction of THOR with IGF2BP1 and show that THOR contributes to the mRNA stabilization activities of IGF2BP1. Notably, transgenic THOR knockout produced fertilization defects in zebrafish and also conferred a resistance to melanoma onset. Likewise, ectopic expression of human THOR in zebrafish accelerated the onset of melanoma. THOR represents a novel class of functionally important cancer/testis lncRNAs whose structure and function have undergone positive evolutionary selection.


Subject(s)
Disease Models, Animal , Melanoma/metabolism , RNA, Long Noncoding/metabolism , Zebrafish , Animals , Cell Line, Tumor , Gene Knockout Techniques , Humans , Male , Mice , RNA-Binding Proteins/metabolism , Testis/metabolism
3.
Nature ; 601(7893): 434-439, 2022 01.
Article in English | MEDLINE | ID: mdl-34937944

ABSTRACT

The switch/sucrose non-fermentable (SWI/SNF) complex has a crucial role in chromatin remodelling1 and is altered in over 20% of cancers2,3. Here we developed a proteolysis-targeting chimera (PROTAC) degrader of the SWI/SNF ATPase subunits, SMARCA2 and SMARCA4, called AU-15330. Androgen receptor (AR)+ forkhead box A1 (FOXA1)+ prostate cancer cells are exquisitely sensitive to dual SMARCA2 and SMARCA4 degradation relative to normal and other cancer cell lines. SWI/SNF ATPase degradation rapidly compacts cis-regulatory elements bound by transcription factors that drive prostate cancer cell proliferation, namely AR, FOXA1, ERG and MYC, which dislodges them from chromatin, disables their core enhancer circuitry, and abolishes the downstream oncogenic gene programs. SWI/SNF ATPase degradation also disrupts super-enhancer and promoter looping interactions that wire supra-physiologic expression of the AR, FOXA1 and MYC oncogenes themselves. AU-15330 induces potent inhibition of tumour growth in xenograft models of prostate cancer and synergizes with the AR antagonist enzalutamide, even inducing disease remission in castration-resistant prostate cancer (CRPC) models without toxicity. Thus, impeding SWI/SNF-mediated enhancer accessibility represents a promising therapeutic approach for enhancer-addicted cancers.


Subject(s)
Adenosine Triphosphatases , DNA Helicases , Nuclear Proteins , Prostatic Neoplasms , Transcription Factors , Adenosine Triphosphatases/metabolism , Animals , Benzamides , DNA Helicases/genetics , Enhancer Elements, Genetic , Genes, myc , Hepatocyte Nuclear Factor 3-alpha , Humans , Male , Nitriles , Nuclear Proteins/genetics , Oncogenes , Phenylthiohydantoin , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/genetics , Receptors, Androgen , Transcription Factors/genetics , Transcriptional Regulator ERG , Xenograft Model Antitumor Assays
4.
Proc Natl Acad Sci U S A ; 121(15): e2322563121, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38557192

ABSTRACT

Mammalian switch/sucrose nonfermentable (mSWI/SNF) ATPase degraders have been shown to be effective in enhancer-driven cancers by functioning to impede oncogenic transcription factor chromatin accessibility. Here, we developed AU-24118, an orally bioavailable proteolysis-targeting chimera (PROTAC) degrader of mSWI/SNF ATPases (SMARCA2 and SMARCA4) and PBRM1. AU-24118 demonstrated tumor regression in a model of castration-resistant prostate cancer (CRPC) which was further enhanced with combination enzalutamide treatment, a standard of care androgen receptor (AR) antagonist used in CRPC patients. Importantly, AU-24118 exhibited favorable pharmacokinetic profiles in preclinical analyses in mice and rats, and further toxicity testing in mice showed a favorable safety profile. As acquired resistance is common with targeted cancer therapeutics, experiments were designed to explore potential mechanisms of resistance that may arise with long-term mSWI/SNF ATPase PROTAC treatment. Prostate cancer cell lines exposed to long-term treatment with high doses of a mSWI/SNF ATPase degrader developed SMARCA4 bromodomain mutations and ABCB1 (ATP binding cassette subfamily B member 1) overexpression as acquired mechanisms of resistance. Intriguingly, while SMARCA4 mutations provided specific resistance to mSWI/SNF degraders, ABCB1 overexpression provided broader resistance to other potent PROTAC degraders targeting bromodomain-containing protein 4 and AR. The ABCB1 inhibitor, zosuquidar, reversed resistance to all three PROTAC degraders tested. Combined, these findings position mSWI/SNF degraders for clinical translation for patients with enhancer-driven cancers and define strategies to overcome resistance mechanisms that may arise.


Subject(s)
Adenosine Triphosphatases , Prostatic Neoplasms, Castration-Resistant , Male , Humans , Rats , Mice , Animals , Adenosine Triphosphatases/genetics , Adenosine Triphosphatases/metabolism , Prostatic Neoplasms, Castration-Resistant/drug therapy , Prostatic Neoplasms, Castration-Resistant/genetics , Cell Line , Chromatin , Mammals/genetics , Androgen Receptor Antagonists , DNA Helicases/genetics , Nuclear Proteins/genetics , Transcription Factors/genetics
5.
Proc Natl Acad Sci U S A ; 120(30): e2221809120, 2023 07 25.
Article in English | MEDLINE | ID: mdl-37459541

ABSTRACT

Early in the COVID-19 pandemic, data suggested that males had a higher risk of developing severe disease and that androgen deprivation therapy might be associated with protection. Combined with the fact that TMPRSS2 (transmembrane serine protease 2), a host entry factor for the SARS-CoV-2 virus, was a well-known androgen-regulated gene, this led to an upsurge of research investigating androgen receptor (AR)-targeting drugs. Proxalutamide, an AR antagonist, was shown in initial clinical studies to benefit COVID-19 patients; however, further validation is needed as one study was retracted. Due to continued interest in proxalutamide, which is in phase 3 trials, we examined its ability to impact SARS-CoV-2 infection and downstream inflammatory responses. Proxalutamide exerted similar effects as enzalutamide, an AR antagonist prescribed for advanced prostate cancer, in decreasing AR signaling and expression of TMPRSS2 and angiotensin-converting enzyme 2 (ACE2), the SARS-CoV-2 receptor. However, proxalutamide led to degradation of AR protein, which was not observed with enzalutamide. Proxalutamide inhibited SARS-CoV-2 infection with an IC50 value of 97 nM, compared to 281 nM for enzalutamide. Importantly, proxalutamide inhibited infection by multiple SARS-CoV-2 variants and synergized with remdesivir. Proxalutamide protected against cell death in response to tumor necrosis factor alpha and interferon gamma, and overall survival of mice was increased with proxalutamide treatment prior to cytokine exposure. Mechanistically, we found that proxalutamide increased levels of NRF2, an essential transcription factor that mediates antioxidant responses, and decreased lung inflammation. These data provide compelling evidence that proxalutamide can prevent SARS-CoV-2 infection and cytokine-induced lung damage, suggesting that promising clinical data may emerge from ongoing phase 3 trials.


Subject(s)
COVID-19 , Prostatic Neoplasms , Male , Humans , Animals , Mice , SARS-CoV-2/metabolism , Androgens , Androgen Antagonists/therapeutic use , Pandemics , Peptidyl-Dipeptidase A/metabolism , Prostatic Neoplasms/drug therapy , Interferon-gamma/therapeutic use
6.
Proc Natl Acad Sci U S A ; 120(49): e2314416120, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-38011559

ABSTRACT

Despite the remarkable clinical success of immunotherapies in a subset of cancer patients, many fail to respond to treatment and exhibit resistance. Here, we found that genetic or pharmacologic inhibition of the lipid kinase PIKfyve, a regulator of autophagic flux and lysosomal biogenesis, upregulated surface expression of major histocompatibility complex class I (MHC-I) in cancer cells via impairing autophagic flux, resulting in enhanced cancer cell killing mediated by CD8+ T cells. Genetic depletion or pharmacologic inhibition of PIKfyve elevated tumor-specific MHC-I surface expression, increased intratumoral functional CD8+ T cells, and slowed tumor progression in multiple syngeneic mouse models. Importantly, enhanced antitumor responses by Pikfyve-depletion were CD8+ T cell- and MHC-I-dependent, as CD8+ T cell depletion or B2m knockout rescued tumor growth. Furthermore, PIKfyve inhibition improved response to immune checkpoint blockade (ICB), adoptive cell therapy, and a therapeutic vaccine. High expression of PIKFYVE was also predictive of poor response to ICB and prognostic of poor survival in ICB-treated cohorts. Collectively, our findings show that targeting PIKfyve enhances immunotherapies by elevating surface expression of MHC-I in cancer cells, and PIKfyve inhibitors have potential as agents to increase immunotherapy response in cancer patients.


Subject(s)
CD8-Positive T-Lymphocytes , Neoplasms , Mice , Animals , Humans , Genes, MHC Class I , Histocompatibility Antigens Class I , Immunotherapy/methods , Lipids , Neoplasms/genetics , Neoplasms/therapy
8.
Proc Natl Acad Sci U S A ; 118(36)2021 09 07.
Article in English | MEDLINE | ID: mdl-34413211

ABSTRACT

The global spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and the associated disease COVID-19, requires therapeutic interventions that can be rapidly identified and translated to clinical care. Traditional drug discovery methods have a >90% failure rate and can take 10 to 15 y from target identification to clinical use. In contrast, drug repurposing can significantly accelerate translation. We developed a quantitative high-throughput screen to identify efficacious agents against SARS-CoV-2. From a library of 1,425 US Food and Drug Administration (FDA)-approved compounds and clinical candidates, we identified 17 hits that inhibited SARS-CoV-2 infection and analyzed their antiviral activity across multiple cell lines, including lymph node carcinoma of the prostate (LNCaP) cells and a physiologically relevant model of alveolar epithelial type 2 cells (iAEC2s). Additionally, we found that inhibitors of the Ras/Raf/MEK/ERK signaling pathway exacerbate SARS-CoV-2 infection in vitro. Notably, we discovered that lactoferrin, a glycoprotein found in secretory fluids including mammalian milk, inhibits SARS-CoV-2 infection in the nanomolar range in all cell models with multiple modes of action, including blockage of virus attachment to cellular heparan sulfate and enhancement of interferon responses. Given its safety profile, lactoferrin is a readily translatable therapeutic option for the management of COVID-19.


Subject(s)
Antiviral Agents/pharmacology , Immunologic Factors/pharmacology , Lactoferrin/pharmacology , SARS-CoV-2/drug effects , Virus Internalization/drug effects , Virus Replication/drug effects , Animals , COVID-19/immunology , COVID-19/prevention & control , COVID-19/virology , Caco-2 Cells , Cell Line, Tumor , Chlorocebus aethiops , Dose-Response Relationship, Drug , Drug Discovery , Drug Repositioning/methods , Epithelial Cells , Heparitin Sulfate/antagonists & inhibitors , Heparitin Sulfate/immunology , Heparitin Sulfate/metabolism , Hepatocytes , High-Throughput Screening Assays , Humans , SARS-CoV-2/growth & development , SARS-CoV-2/pathogenicity , Vero Cells , COVID-19 Drug Treatment
9.
Proc Natl Acad Sci U S A ; 118(1): e2021450118, 2021 Jan 05.
Article in English | MEDLINE | ID: mdl-33310900

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for COVID-19, employs two key host proteins to gain entry and replicate within cells, angiotensin-converting enzyme 2 (ACE2) and the cell surface transmembrane protease serine 2 (TMPRSS2). TMPRSS2 was first characterized as an androgen-regulated gene in the prostate. Supporting a role for sex hormones, males relative to females are disproportionately affected by COVID-19 in terms of mortality and morbidity. Several studies, including one employing a large epidemiological cohort, suggested that blocking androgen signaling is protective against COVID-19. Here, we demonstrate that androgens regulate the expression of ACE2, TMPRSS2, and androgen receptor (AR) in subsets of lung epithelial cells. AR levels are markedly elevated in males relative to females greater than 70 y of age. In males greater than 70 y old, smoking was associated with elevated levels of AR and ACE2 in lung epithelial cells. Transcriptional repression of the AR enhanceosome with AR or bromodomain and extraterminal domain (BET) antagonists inhibited SARS-CoV-2 infection in vitro. Taken together, these studies support further investigation of transcriptional inhibition of critical host factors in the treatment or prevention of COVID-19.

10.
Neurol Sci ; 44(10): 3615-3627, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37162664

ABSTRACT

OBJECTIVE: To develop and validate a machine learning (ML)-based model to predict functional outcome in Chinese patients with intracerebral hemorrhage (ICH). METHODS: This retrospective cohort study enrolled patients with ICH between November 2017 and November 2020. The follow-up period ended in February 2021. The study population was divided into training and testing sets with a ratio of 7:3. All variables were included in the least absolute shrinkage and selection operator (LASSO) regression for feature selection. The selected variables were incorporated into the random forest algorithm to construct the prediction model. The predictive performance of the model was evaluated via the area under the curve (AUC), accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and calibration curve. RESULTS: A total of 412 ICH patients were included, with 288 in the training set, and 124 in the testing set. Twelve attributes were selected: neurological deterioration, Glasgow Coma Scale (GCS) score at 24 h, baseline GCS score, time from onset to the emergency room, blood glucose, diastolic blood pressure (DBP) change in 24 h, hematoma volume change in 24 h, systemic immune-inflammatory index (SII), systolic blood pressure (SBP) change in 24 h, serum creatinine, serum sodium, and age. In the testing set, the accuracy, AUC, sensitivity, specificity, PPV, and NPV of the model were 0.895, 0.964, 0.872, 0.906, 0.810, and 0.939, respectively. The calibration curves showed a good calibration capability of the model. CONCLUSION: This developed random forest model performed well in predicting 3-month poor functional outcome for Chinese ICH patients.


Subject(s)
Cerebral Hemorrhage , Random Forest , Humans , Retrospective Studies , Cerebral Hemorrhage/diagnosis , Predictive Value of Tests , Hematoma
11.
Inorg Chem ; 61(42): 16528-16532, 2022 Oct 24.
Article in English | MEDLINE | ID: mdl-36239584

ABSTRACT

A novel telluroniobate, K8Na6H7{[Co(en)2(SO3)][Te4Nb24O79]}·42H2O (en = ethylenediamine), has been synthesized through a diffusion strategy. It consists of a heteropolyoxoniobate [B-ß-TeNb9O33]17- cluster and isopolyoxoniobate {Nb7O22} building blocks. In addition, its structure was fully characterized by a series of spectroscopic methods. Furthermore, it exhibits an efficient catalytic performance in the transesterification of ethylene carbonate and methanol to prepare dimethyl carbonate with good catalytic reusability. Also, it demonstrates interesting proton conduction properties, with conductivity achieved at 3.05 × 10-4 S cm-1 (60 °C, 75% relative humidity).

12.
Phys Chem Chem Phys ; 23(1): 617-627, 2021 Jan 06.
Article in English | MEDLINE | ID: mdl-33331372

ABSTRACT

The entire reaction mechanism of the dry reforming of methane (DRM) as well as the competition processes over perfect and boron-vacancy-containing h-BN sheet-supported Ni-catalysts (labeled Ni2/h-BN and Ni2/h-BN-B-D) was studied by density functional theory calculations in the present work. Our calculation results show that B-defected h-BN strongly binds to the Ni2 active sites (i.e., shows a strong metal-support interaction (SMSI) character) due to the better electron transfer between Ni2 sites and the support. It was found that CH4 is easier to activate than molecular CO2. The activation of CO2 occurs on the surface of Ni2/h-BN through a direct route, whereas it is prone to follow a hydrogen-assisted path for Ni2/h-BN-B-D via the COOH* intermediate, and the results show that the oxidant O* is easily formed on the surface of Ni2/h-BN-B-D. It was also found that O* is the main oxidant agent for CHx* intermediates through the CH3-O oxidation mechanism. The reaction kinetic analysis indicated that the reverse water gas shift reaction (RWGS) is much more favorable than DRM (1.30 vs. 1.72 eV) over the Ni2/h-BN system, whereas the RWGS and DRM are comparable on Ni2/h-BN-B-D (1.77 vs. 1.66 eV), suggesting a high DRM activity on Ni2/h-BN-B-D. Moreover, neither methane cracking nor a Boudouard reaction to form C* species is thermodynamically and kinetically unfavorable over Ni2/h-BN-B-D; hence, Ni2/h-BN-B-D has strong resistance to carbon deposition. Compared to Ni(111), both Ni2/h-BN-B-D and Ni2/h-BN show strong resistance to carbon deposition. Our results provide a further mechanistic understanding of the DRM over an Ni-based catalyst through the SMSI characteristic and the SMSI favors strong resistance to carbon deposition.

13.
Inorg Chem ; 59(12): 7895-7899, 2020 Jun 15.
Article in English | MEDLINE | ID: mdl-32496063

ABSTRACT

A new organic-inorganic hybrid heteropolyoxoniobate, [{Cu(en)(H2O)4}{Cu(en)2(H2O)}{Cu(en)2(H2O)2}]1.5[H8SiTe8Nb15O64]·6H2O (1; en = ethanediamine), has been successfully synthesized by a conventional method. The compound was directed by pairs of [TeO3]2-/[SiO3]2- ions, generating two novel {TeNb9} and {SiTeNb6} subunits in situ owing to the mixed heteroanion. In addition, the solution behavior of compound 1 was investigated.

14.
Inorg Chem ; 59(3): 1967-1972, 2020 Feb 03.
Article in English | MEDLINE | ID: mdl-31940183

ABSTRACT

A novel polyoxoniobate cluster directed by AsO33-, {[Cu(phen)]5[Nb6O19][As2Nb6O22]}2 (1a), has been successfully synthesized by a "two-pot" strategy, namely, the conventional aqueous solution and diffusional methods. It incorporates two {[Cu(phen)]2Nb6O19} and two {[Cu(phen)]3As2Nb6O22} subunits. Surprisingly, by changing the reaction conditions, one of the subunits {[Cu(phen)]2Nb6O19} was isolated as a guanidinium salt. These architectures were structurally characterized by single crystal X-ray diffraction, TGA, IR, elemental analysis and PXRD, etc. Furthermore, the behavior of 1 in aqueous solution was measured by electrospray ionization mass spectrometry, and the magnetic property in the low temperature range indicates the presence of antiferromagnetic interactions.

15.
Sensors (Basel) ; 20(9)2020 Apr 25.
Article in English | MEDLINE | ID: mdl-32344855

ABSTRACT

Vehicle evaluation parameters, which are increasingly of concern for governments and consumers, quantify performance indicators, such as vehicle performance, emissions, and driving experience to help guide consumers in purchasing cars. While past approaches for driving cycle prediction have been proven effective and used in many countries, these algorithms are difficult to use in China with its complex traffic environment and increasingly high frequency of traffic jams. Meanwhile, we found that the vehicle dataset used by the driving cycle prediction problem is usually unbalanced in real cases, which means that there are more medium and high speed samples and very few samples at low and ultra-high speeds. If the ordinary clustering algorithm is directly applied to the unbalanced data, it will have a huge impact on the performance to build driving cycle maps, and the parameters of the map will deviate considerable from actual ones. In order to address these issues, this paper propose a novel driving cycle map algorithm framework based on an ensemble learning method named multi-clustering algorithm, to improve the performance of traditional clustering algorithms on unbalanced data sets. It is noteworthy that our model framework can be easily extended to other complicated structure areas due to its flexible modular design and parameter configuration. Finally, we tested our method based on actual traffic data generated in Fujian Province in China. The results prove the multi-clustering algorithm has excellent performance on our dataset.

16.
Int J Cancer ; 145(2): 415-426, 2019 07 15.
Article in English | MEDLINE | ID: mdl-30628724

ABSTRACT

Polycomb group proteins are important epigenetic regulators for cell proliferation and differentiation, organ development, as well as initiation and progression of lethal diseases, including cancer. Upregulated Polycomb group proteins, including Enhancer of zeste homolog 2 (EZH2), promote proliferation, migration, invasion and metastasis of cancer cells, as well as self-renewal of cancer stem cells. In our study, we report that EZH2 and embryonic ectoderm development (EED) indicate respective direct interaction with androgen receptor (AR). In the context of AR-positive prostate cancer, EZH2 and EED regulate AR expression levels and AR downstream targets. More importantly, we demonstrate that targeting EZH2 with the small-molecule inhibitor astemizole in cancer significantly represses the EZH2 and AR expression as well as the neoplastic capacities. These results collectively suggest that pharmacologically targeting EZH2 might be a promising strategy for advanced prostate cancer.


Subject(s)
Astemizole/administration & dosage , Enhancer of Zeste Homolog 2 Protein/metabolism , Polycomb Repressive Complex 2/metabolism , Prostatic Neoplasms/pathology , Receptors, Androgen/metabolism , Animals , Astemizole/pharmacology , Cell Line, Tumor , Gene Expression Regulation, Neoplastic/drug effects , Humans , Male , Mice , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/metabolism , Receptors, Androgen/genetics , Sequence Analysis, RNA , Signal Transduction/drug effects , Xenograft Model Antitumor Assays
17.
Inorg Chem ; 58(19): 13030-13036, 2019 Oct 07.
Article in English | MEDLINE | ID: mdl-31518117

ABSTRACT

Eight novel lanthanide-containing polyoxotantalates, Cs3[Ln(H2O)6{H4(TaO2)6As4O24}]·7H2O (Ln = Sm (1), Eu (2), Tb (3), Dy (4), Er (5), Tm (6), Yb (7), Lu (8)), have been obtained via a one-pot reaction methodology. Each of these compounds is made up of the new type polyanion [(TaO2)6As4O24]10- with Ln3+ linkers, giving a one-dimensional chain. The compounds represent the first family of "pure" Ta-based polyoxometalate lanthanide derivatives. These architectures were characterized by various physicochemical analyses. Furthermore, the photoluminescence properties of compounds 2-Eu and 8-Lu were also explored, and meanwhile time-resolved emission spectroscopy indicated that the {As4Ta6} segment makes a contribution to the energy transfer of compound 2 from the polyoxotantalate to the EuIII center, which efficiently facilitates emissions of the Eu3+ center.

18.
Clin Lab ; 65(7)2019 Jul 01.
Article in English | MEDLINE | ID: mdl-31307159

ABSTRACT

BACKGROUND: Recently, many broadly applicable and potent neutralizing antibodies have been screened from HIV-1-infected patients. However, all these effective neutralizing antibodies were isolated from patients naive to anti-retroviral treatment (ART). METHODS: To better understand the induction of neutralizing antibodies in patients on ART, we screened 3 patients with an over ten-year infection history on ART from 350 patients in China for a cross-reactive neutralizing antibody response based on the use of different antigens and recombinant viruses. We studied the evolution of neutralizing activity in two patients during a one-year period with previously described recombinant viruses NL4-3 and SF162 using ELISA and neutralization assays. RESULTS: Antibodies purified from sera were able to react with recombinant virus antigens R2-gp120 and SF162-gp140 and neutralize SF162 recombinant virus but not NL4-3 recombinant virus. In addition, we observed a significant increase in the neutralizing response of immunoglobulin G (IgG) isolated from the serum sample in Patient 1 and compared it with the serum from Patient 1 six months ago. CONCLUSIONS: We thus confirm the possibility of production of neutralizing antibodies in patients infected for over ten years on ART, and it is possible over time of the improvement of HIV-1 potent neutralizing activity associated with viremia and immune reconstruction.


Subject(s)
Anti-Retroviral Agents/therapeutic use , Antibodies, Neutralizing/immunology , Antiretroviral Therapy, Highly Active , HIV Antibodies/immunology , HIV Infections/drug therapy , HIV-1/drug effects , Anti-Retroviral Agents/immunology , Antibodies, Neutralizing/blood , CD4 Lymphocyte Count , Cross Reactions/immunology , HIV Antibodies/blood , HIV Envelope Protein gp120/immunology , HIV Infections/immunology , HIV Infections/virology , HIV-1/immunology , HIV-1/physiology , Humans , Immunoglobulin G/blood , Immunoglobulin G/immunology , Male , Viremia/drug therapy , Viremia/immunology , env Gene Products, Human Immunodeficiency Virus/immunology
19.
J Therm Biol ; 76: 29-37, 2018 Aug.
Article in English | MEDLINE | ID: mdl-30143294

ABSTRACT

The treatment of hypothermia suffered by naval fighters owing to seawater immersion has been a focus of research in recent years. Currently, the treatment of hypothermia in China is limited to external rewarming, which is of low efficiency and is not effective for patients suffering moderate to severe hypothermia. We thus proposed a vascular interventional heating method which directly heats the blood flow via a minimally invasive heating needle for rewarming. And a numerical simulation using a compartment model based on finite difference method was conducted. A set of whole body heating treatment simulation was also developed. Appropriate treatment parameters and procedures can be set and adjusted based on patient physical parameters. Here temperature response curves of different heating modes were obtained and analyzed. It was demonstrated that the desired thermal response can be achieved by adjusting the heating power and heating time, ensuring controllable accuracy in the treatment of patients with severe hypothermia. The proposed treatment for hypothermia is a new and effective alternative, and further progress is expected in clinical trials.


Subject(s)
Cardiovascular Physiological Phenomena , Hypothermia/therapy , Models, Biological , Rewarming/instrumentation , Rewarming/methods , Body Temperature , Humans
20.
J Virol ; 89(24): 12467-79, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26446597

ABSTRACT

UNLABELLED: The peptide drug enfuvirtide (T20) is the only HIV-1 fusion inhibitor in clinical use, but it easily induces drug resistance, calling for new strategies for developing effective drugs. On the basis of the M-T hook structure, we recently developed highly potent short-peptide HIV-1 fusion inhibitors (MTSC22 and HP23), which mainly target the conserved gp41 pocket and possess high genetic barriers to resistance. Here, we focused on the selection and characterization of HIV-1 escape mutants of MTSC22, which revealed new resistance pathways and mechanisms. Two mutations (E49K and L57R) located at the inhibitor-binding site and two mutations (N126K and E136G) located at the C-terminal heptad repeat region of gp41 were identified as conferring high resistance either singly or in combination. While E49K reduced the C-terminal binding of inhibitors via an electrostatic repulsion, L57R dramatically disrupted the N-terminal binding of M-T hook structure and pocket-binding domain. Unlike E49K and N126K, which enhanced the stability of the endogenous viral six-helical bundle core (6-HB), L57R and E136G conversely destabilized the 6-HB structure. We also demonstrated that both primary and secondary mutations caused the structural changes in 6-HB and severely impaired the capability for HIV-1 entry. Collectively, our data provide novel insights into the mechanisms of short-peptide fusion inhibitors targeting the gp41 pocket site and help increase our understanding of the structure and function of gp41 and HIV-1 evolution. IMPORTANCE: The deep pocket on the N-trimer of HIV-1 gp41 has been considered an ideal drug target because of its high degree of conservation and essential role in viral entry. Short-peptide fusion inhibitors, which contain an M-T hook structure and mainly target the pocket site, show extremely high binding and inhibitory activities as well as high genetic barriers to resistance. In this study, the HIV-1 mutants resistant to MTSC22 were selected and characterized, which revealed that the E49K and L57R substitutions at the inhibitor-binding site and the N126K and E136G substitutions at the C-terminal heptad repeat region of gp41 critically determine the resistance phenotype. The data provide novel insights into the mechanisms of action of the M-T hook structure-based fusion inhibitors which will help further our understanding of the structure-function relationship of gp41 and molecular pathways of HIV-1 evolution and eventually facilitate the development of new anti-HIV drugs.


Subject(s)
Drug Resistance, Viral , HIV Envelope Protein gp41 , HIV Fusion Inhibitors/chemistry , HIV-1 , Mutation, Missense , Virus Internalization , Amino Acid Substitution , Cell Line , HIV Envelope Protein gp41/chemistry , HIV Envelope Protein gp41/genetics , HIV Envelope Protein gp41/metabolism , HIV-1/chemistry , HIV-1/genetics , HIV-1/metabolism , Humans , Protein Structure, Secondary
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