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1.
Nature ; 591(7850): 413-419, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33618348

RESUMEN

The deep population history of East Asia remains poorly understood owing to a lack of ancient DNA data and sparse sampling of present-day people1,2. Here we report genome-wide data from 166 East Asian individuals dating to between 6000 BC and AD 1000 and 46 present-day groups. Hunter-gatherers from Japan, the Amur River Basin, and people of Neolithic and Iron Age Taiwan and the Tibetan Plateau are linked by a deeply splitting lineage that probably reflects a coastal migration during the Late Pleistocene epoch. We also follow expansions during the subsequent Holocene epoch from four regions. First, hunter-gatherers from Mongolia and the Amur River Basin have ancestry shared by individuals who speak Mongolic and Tungusic languages, but do not carry ancestry characteristic of farmers from the West Liao River region (around 3000 BC), which contradicts theories that the expansion of these farmers spread the Mongolic and Tungusic proto-languages. Second, farmers from the Yellow River Basin (around 3000 BC) probably spread Sino-Tibetan languages, as their ancestry dispersed both to Tibet-where it forms approximately 84% of the gene pool in some groups-and to the Central Plain, where it has contributed around 59-84% to modern Han Chinese groups. Third, people from Taiwan from around 1300 BC to AD 800 derived approximately 75% of their ancestry from a lineage that is widespread in modern individuals who speak Austronesian, Tai-Kadai and Austroasiatic languages, and that we hypothesize derives from farmers of the Yangtze River Valley. Ancient people from Taiwan also derived about 25% of their ancestry from a northern lineage that is related to, but different from, farmers of the Yellow River Basin, which suggests an additional north-to-south expansion. Fourth, ancestry from Yamnaya Steppe pastoralists arrived in western Mongolia after around 3000 BC but was displaced by previously established lineages even while it persisted in western China, as would be expected if this ancestry was associated with the spread of proto-Tocharian Indo-European languages. Two later gene flows affected western Mongolia: migrants after around 2000 BC with Yamnaya and European farmer ancestry, and episodic influences of later groups with ancestry from Turan.


Asunto(s)
Genoma Humano/genética , Genómica , Migración Humana/historia , China , Producción de Cultivos/historia , Femenino , Haplotipos/genética , Historia Antigua , Humanos , Japón , Lenguaje/historia , Masculino , Mongolia , Nepal , Oryza , Polimorfismo de Nucleótido Simple/genética , Siberia , Taiwán
2.
J Am Chem Soc ; 146(12): 8668-8676, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38498937

RESUMEN

Understanding the valency and structural variations of metal centers during reactions is important for mechanistic studies of single-atom catalysis, which could be beneficial for optimizing reactions and designing new protocols. Herein, we precisely developed a single-atom Cu(I)-N4 site catalyst via a photoinduced ligand exchange (PILE) strategy. The low-valent and electron-rich copper species could catalyze hydrophosphinylation via a novel single-electron oxidative addition (OA) pathway under light irradiation, which could considerably decrease the energy barrier compared with the well-known hydrogen atom transfer (HAT) and single electron transfer (SET) processes. The Cu(I)-Cu(II)-Cu(I) catalytic cycle, via single-electron oxidative addition and photoreduction, has been proven by multiple in situ or operando techniques. This catalytic system demonstrates high efficiency and requires room temperature conditions and no additives, which improves the turnover frequency (TOF) to 1507 h-1. In particular, this unique mechanism has broken through the substrate limitation and shows a broad scope for different electronic effects of alkenes and alkynes.

3.
Small ; 20(25): e2308265, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38225704

RESUMEN

Bispecific antibodies possess exceptional potential as therapeutic agents due to their capacity to bind to two different antigens simultaneously. However, challenges pertain to unsatisfactory stability, manufacturing complexity, and limited tumor penetration hinder their broad applicability. In this study, a versatile technology is presented for the rapid generation of bispecific nanobody-aptamer conjugates with efficient tumor penetration. The approach utilizes microbial transglutaminase (MTGase) and click chemistry to achieve site-specific conjugation of nanobodies and aptamers, which are termed nanotamers. The nanotamers recognize and bind to two types of molecular targets expressed on cancer cells. As a prototype, a bispecific nanotamer is developed that binds both clusters of differentiation 47 (CD47) and mesenchymal epithelial transition receptor (Met) expressed on the tumor cell membrane. This CD47-Met nanotamer demonstrates high affinity and specificity toward tumor cells expressing both targets, exhibits improved receptor functional inhibition through a strong steric hindrance effect. Moreover, its capacity for deep tumor penetration greatly enhances the impact of conventional chemotherapy on antitumor efficacy. The as-developed nanotamer synthesis approach shows promise to customize bispecific molecular probes targeting different cancer types and different therapeutic goals.


Asunto(s)
Anticuerpos Biespecíficos , Aptámeros de Nucleótidos , Neoplasias , Anticuerpos de Dominio Único , Humanos , Aptámeros de Nucleótidos/química , Anticuerpos de Dominio Único/química , Anticuerpos de Dominio Único/farmacología , Neoplasias/tratamiento farmacológico , Anticuerpos Biespecíficos/química , Anticuerpos Biespecíficos/farmacología , Anticuerpos Biespecíficos/uso terapéutico , Línea Celular Tumoral , Animales
4.
Small ; : e2310563, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38757918

RESUMEN

Carbon dots (CDs) have received considerable attention in many application areas owing to their unique optical properties and potential applications; however, the fluorescent mechanism is an obstacle to their applications. Herein, three-color emissive CDs are prepared from single o-phenylenediamine (oPD) by regulating the ratio of ethanol and dimethylformamide (DMF). Fluorescent mechanism of these CDs is proposed as molecular state fluorescence. Reaction intermediates are identified using liquid chromatrography-mass spectroscopy (LC-MS) and 1H nuclear magnetic resonance (NMR) spectra. 1H-Benzo[d]imidazole (BI), 2,3-diaminophenazine (DAP), and 5,14-dihydroquinoxalino[2,3-b] phenazine (DHQP) are proposed to be the fluorophores of blue, green, and red emissive CDs by comparing their optical properties. As per the LC-MS and 1H-NMR analysis, DHQP with red emission tends to form from DAP and oPD in pure ethanol. By adding DMF, BI formation is enhanced and DHQP formation is suppressed. The prepared CDs exhibit green emission with DAP. When the DMF amount is >50%, BI formation is considerably promoted, resulting in DAP formation being suppressed. BI with blue emission then turns into the fluorophore of CDs. This result provides us an improved understanding of the fluorescent mechanism of oPD-based CDs, which guides us in designing the structure and optical properties of CDs.

5.
Mol Divers ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38935305

RESUMEN

The urokinase-type plasminogen activator receptor (uPAR) emerges as a key target for anti-metastasis owing to its pivotal role in facilitating the invasive and migratory processes of cancer cells. Recently, we identified the uPAR-targeting anti-metastatic ability of diltiazem (22), a commonly used antihypertensive agent. Fine-tuning the chemical structures of known hits represents a vital branch of drug development. To develop novel anti-metastatic drugs, we performed an interface-driven structural evolution strategy on 22. The uPAR-targeting and anti-cancer abilities of this antihypertensive drug wereidentified by us recently. Based on in silico strategy, including extensive molecular dynamics (MD) simulations, hierarchical binding free energy predictions, and ADMET profilings, we designed, synthesized, and identified three new diltiazem derivatives (221-8, 221-57, and 221-68) as uPAR inhibitors. Indeed, all of these three derivatives exhibited uPAR-depending inhibitory activity against PC-3 cell line invasion at micromolar level. Particularly, derivatives 221-68 and 221-8 showed enhanced uPAR-dependent inhibitory activity against the tumor cell invasion compared to the original compound. Microsecond timesclae MD simulations demonstrated the optimized moiety of 221-68 and 221-8 forming more comprehensive interactions with the uPAR, highlighting the reasonability of our strategy. This work introduces three novel uPAR inhibitors, which not only pave the way for the development of effective anti-metastatic therapeutics, but also emphasize the efficacy and robustness of an in silico-based lead compound optimization strategy in drug design.

6.
Lipids Health Dis ; 23(1): 68, 2024 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-38431645

RESUMEN

BACKGROUND: Stress is implicated in various pathological conditions leading to liver injury. Existing evidence suggests that excessive stress can induce mitochondrial damage in hepatocytes, yet the underlying mechanism remains unclear. Ceramide synthase 6 (CerS6)-derived C16:0 ceramide is recognised as a lipotoxic substance capable of causing mitochondrial damage. However, the role of CerS6 in stress has received insufficient attention. This study aimed to explore the involvement of CerS6 in stress-induced hepatic damage and its associated mechanisms. METHODS: The rat restraint stress model and a corticosterone (CORT)-induced hepatocyte stress model were employed for in vivo and in vitro experimental analyses, respectively. Changes in mitochondrial damage and ceramide metabolism in hepatocytes induced by stress were evaluated. The impact of CORT on mitochondrial damage and ceramide metabolism in hepatocytes was assessed following CerS6 knockdown. Mitochondria were isolated using a commercial kit, and ceramides in liver tissue and hepatocytes were detected by LC-MS/MS. RESULTS: In comparison to the control group, rats subjected to one week of restraint exhibited elevated serum CORT levels. The liver displayed significant signs of mitochondrial damage, accompanied by increased CerS6 and mitochondrial C16:0 ceramide, along with activation of the AMPK/p38 MAPK pathway. In vitro studies demonstrated that CORT treatment of hepatocytes resulted in mitochondrial damage, concomitant with elevated CerS6 and mitochondrial C16:0 ceramide. Furthermore, CORT induced sequential phosphorylation of AMPK and p38 MAPK proteins, and inhibition of the p38 MAPK pathway using SB203580 mitigated the CORT-induced elevation in CerS6 protein. Knocking down CerS6 in hepatocytes inhibited both the increase in C16:0 ceramide and the release of mitochondrial cytochrome c induced by CORT. CONCLUSIONS: CerS6-associated C16:0 ceramide plays a mediating role in stress-induced mitochondrial damage in hepatocytes. The molecular mechanism is linked to CORT-induced activation of the AMPK/p38 MAPK pathway, leading to upregulated CerS6.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Espectrometría de Masas en Tándem , Ratas , Animales , Proteínas Quinasas Activadas por AMP/metabolismo , Cromatografía Liquida , Ceramidas/metabolismo , Hepatocitos/metabolismo , Hígado/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Apoptosis , Esfingosina N-Aciltransferasa/genética , Esfingosina N-Aciltransferasa/metabolismo
7.
J Am Chem Soc ; 145(5): 3175-3186, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36705997

RESUMEN

Oxidation-induced strategy for inert chemical bond activation through highly active radical cation intermediate has exhibited unique reactivity. Understanding the structure and reactivity patterns of radical cation intermediates is crucial in the mechanistic study and will be beneficial for developing new reactions. In this work, the structure and properties of indole radical cations have been revealed using time-resolved transient absorption spectroscopy, in situ electrochemical UV-vis, and in situ electrochemical electron paramagnetic resonance (EPR) technique. Density functional theory (DFT) calculations were used to explain and predict the regioselectivity of several electrochemical oxidative indole annulations. Based on the understanding of the inherent properties of several indole radical cations, two different regioselective annulations of indoles have been successfully developed under electrochemical oxidation conditions. Varieties of furo[2,3-b]indolines and furo[3,2-b]indolines were synthesized in good yields with high regioselectivities. Our mechanistic insights into indole radical cations will promote the further development of oxidation-induced indole functionalizations.

8.
Int J Mol Sci ; 24(7)2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-37047540

RESUMEN

We prepared three-dimensional (3-D) organoids of human stomach cancers and examined the correlation between the tumorigenicity and cytotoxicity of Helicobacter pylori (H. pylori). In addition, the effects of hepatoma-derived growth factor (HDGF) and tumor necrosis factor (TNFα) on the growth and invasion activity of H. pylori-infected gastric cancer organoids were examined. Cytotoxin-associated gene A (CagA)-green fluorescence protein (GFP)-labeled H. pylori was used to trace the infection in gastric organoids. The cytotoxicity of Cag encoded toxins from different species of H. pylori did not affect the proliferation of each H. pylori-infected cancer organoid. To clarify the role of HDGF and TNFα secreted from H. pylori-infected cancer organoids, we prepared recombinant HDGF and TNFα and measured the cytotoxicity and invasion of gastric cancer organoids. HDGF controlled the growth of each organoid in a species-specific manner of H. pylori, but TNFα decreased the cell viability in H. pylori-infected cancer organoids. Furthermore, HDGF controlled the invasion activity of H. pylori-infected cancer organoid in a species-dependent manner. However, TNFα decreased the invasion activities of most organoids. We found different signaling of cytotoxicity and invasion of human gastric organoids in response to HDGF and TNFα during infection by H. pylori. Recombinant HDGF and TNFα inhibited the development and invasion of H. pylori-infected gastric cancer differently. Thus, we propose that HDGF and TNFα are independent signals for development of H. pylori-infected gastric cancer. The signaling of growth factors in 3-D organoid culture systems is different from those in two-dimensional cancer cells.


Asunto(s)
Carcinoma Hepatocelular , Infecciones por Helicobacter , Helicobacter pylori , Neoplasias Hepáticas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patología , Factor de Necrosis Tumoral alfa/metabolismo , Helicobacter pylori/metabolismo , Antígenos Bacterianos/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Organoides/metabolismo , Infecciones por Helicobacter/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/farmacología , Proteínas Bacterianas/metabolismo
9.
Int J Mol Sci ; 24(21)2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37958895

RESUMEN

Gastric cancer (GC) organoids are frequently used to examine cell proliferation and death as well as cancer development. Invasion/migration assay, xenotransplantation, and reactive oxygen species (ROS) production were used to examine the effects of antioxidant drugs, including perillaldehyde (PEA), cinnamaldehyde (CA), and sulforaphane (SFN), on GC. PEA and CA repressed the proliferation of human GC organoids, whereas SFN enhanced it. Caspase 3 activities were also repressed on treatment with PEA and CA. Furthermore, the tumor formation and invasive activities were repressed on treatment with PEA and CA, whereas they were enhanced on treatment with SFN. These results in three-dimensional (3D)-GC organoids showed the different cancer development of phase II enzyme ligands in 2D-GC cells. ROS production and the expression of TP53, nuclear factor erythroid 2-related factor (NRF2), and Jun dimerization protein 2 were also downregulated on treatment with PEA and CA, but not SFN. NRF2 knockdown reversed the effects of these antioxidant drugs on the invasive activities of the 3D-GC organoids. Moreover, ROS production was also inhibited by treatment with PEA and CA, but not SFN. Thus, NRF2 plays a key role in the differential effects of these antioxidant drugs on cancer progression in 3D-GC organoids. PEA and CA can potentially be new antitumorigenic therapeutics for GC.


Asunto(s)
Antioxidantes , Neoplasias Gástricas , Humanos , Antioxidantes/farmacología , Apoptosis , Tratamiento Basado en Trasplante de Células y Tejidos , Isotiocianatos/farmacología , Isotiocianatos/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Organoides/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/metabolismo , Sulfóxidos/farmacología
10.
J Org Chem ; 87(1): 1-9, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34677067

RESUMEN

A rapid on-bead convergent method for preparing branched peptides was reported. Linear peptides were prepared on Dbz resin and ligated various branched cores, including lysine dendrons and other dendritic compounds. Alongside microwave irradiation, <1.5 equiv of peptides is sufficient to afford 50-65% yields of pure branched peptides without chromatographic purification. Remarkably, the desired compounds were prepared within hours.


Asunto(s)
Microondas , Péptidos
11.
Int J Med Sci ; 19(10): 1615-1627, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36185333

RESUMEN

In recent years, translational research and pharmacological targeting of epigenetic modifications have become the focus of personalized therapy for patients with pancreatic cancer. Preclinical and clinical trials targeting post-translational modifications have been evaluated as monotherapy or in combination with standard chemotherapy. In this study, we selected 43 genes from seven families of chromatin-modifying enzymes and investigated the influences of epigenetic modifications and their interactions on pancreatic ductal adenocarcinoma (PDAC) using hierarchical clustering analysis. Our analysis also evaluated their effects on treatment modalities and regimens of chemotherapy for PDAC. RNA-seq data for a total of 177 patients with pancreatic cancer, obtained from The Cancer Genome Atlas database, were analyzed. Our results suggested that high-risk patients of survival significant chromatin remodeling-associated gene cluster (gene cluster 2), composed of histone methyltransferases, histone acetyltransferases, histone deacetylases, histone demethylases, and 10-11 translocation family, demonstrated inferior progression-free survival and overall survival in patients with PDAC, especially in men. Our novel biomarker, survival significant chromatin remodeling-associated gene cluster, showed superior prediction performance compared with the conventional TNM system. Overall, these findings suggest that epigenetic modifications and interactions play an important role in the prognosis and therapeutic response of patients with PDAC.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/genética , Cromatina/genética , Ensamble y Desensamble de Cromatina/genética , Análisis por Conglomerados , Histona Acetiltransferasas/genética , Histona Desacetilasas/genética , Histona Desacetilasas/metabolismo , Histona Metiltransferasas/genética , Histonas/metabolismo , Humanos , Masculino , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Pronóstico , Neoplasias Pancreáticas
12.
J Formos Med Assoc ; 121(10): 2123-2129, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35570052

RESUMEN

PURPOSE: To compare a lateral-flow device (LFD) method to the galactomannan assay (GM) for the diagnosis of invasive aspergillosis (IA). METHODS: First, 20 GM-positive serum samples stored for two years were retested with both the GM and LFD assays. Second, 153 serum samples from 91 immunocompromised patients suspected of having IA were tested prospectively, including 56 hematologic malignancies and 35 chronic illnesses with steroid therapy. RESULTS: For the twenty GM-positive stored samples, only ten were positive for the repeated GM assay and none were positive for IA according to the LFD test. The concordance of the LDF with the GM test was 79.81% (83/104) if both tests were performed on the sample collection day, with the rate reducing to 67.65% (23/34) (p < 0.05) if the LFD test was performed 2-7 days after the GM test. Furthermore, there was a significant difference in the discrepancy between the GM and LFD tests between previous and no anti-mold exposure subgroups (33.33% vs. 12.31%, p < 0.01). The sensitivity and specificity of the GM test were 89.65% and 98.66%, 68.96%, and 78.67% for the LFD assay. CONCLUSION: Serum samples that have been stored long term are not suitable for re-testing with the GM or LFD assay. There was a strong correlation between the LFD and GM assay results if the tests were performed on the same day, however, this decreased if the samples were stored for more than 2 days. Additionally, previous exposure to antibiotics and/or antifungal therapy could influence the LFD results, leading to discrepancies with the GM test results.


Asunto(s)
Aspergilosis , Infecciones Fúngicas Invasoras , Aspergilosis Pulmonar Invasiva , Antibacterianos , Antifúngicos/uso terapéutico , Antígenos Fúngicos , Aspergilosis/diagnóstico , Aspergillus , Galactosa/análogos & derivados , Humanos , Aspergilosis Pulmonar Invasiva/diagnóstico , Mananos , Sensibilidad y Especificidad , Esteroides
13.
J Am Chem Soc ; 143(49): 20863-20872, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34851107

RESUMEN

Electrochemical synthesis has been rapidly developed over the past few years, while a vast majority of the reactions proceed through a radical pathway. Understanding the properties of radical intermediates is crucial in the mechanistic study of electrochemical transformations and will be beneficial for developing new reactions. Nevertheless, it is rather difficult to determine the "live" radical intermediates due to their high reactivity. In this work, the formation and structure of sulfonamide N-centered radicals have been researched directly by using the time-resolved electron paramagnetic resonance (EPR) technique under electrochemical conditions. Supported by the EPR results, the reactivity of N-centered radicals as a mediator in the hydrogen atom transfer (HAT) approach has been discussed. Subsequently, these mechanistic study results have been successfully utilized in the discovery of an unactivated C(sp3)-H arylation reaction. The kinetic experiments have revealed the rate-determined step is the anodic oxidation of sulfonamides.

14.
Oncologist ; 26(11): e2034-e2041, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34506688

RESUMEN

BACKGROUND: We externally validated Fujimoto's post-transplant lymphoproliferative disorder (PTLD) scoring system for risk prediction by using the Taiwan Blood and Marrow Transplant Registry Database (TBMTRD) and aimed to create a superior scoring system using machine learning methods. MATERIALS AND METHODS: Consecutive allogeneic hematopoietic cell transplant (HCT) recipients registered in the TBMTRD from 2009 to 2018 were included in this study. The Fujimoto PTLD score was calculated for each patient. The machine learning algorithm, least absolute shrinkage and selection operator (LASSO), was used to construct a new score system, which was validated using the fivefold cross-validation method. RESULTS: We identified 2,148 allogeneic HCT recipients, of which 57 (2.65%) developed PTLD in the TBMTRD. In this population, the probabilities for PTLD development by Fujimoto score at 5 years for patients in the low-, intermediate-, high-, and very-high-risk groups were 1.15%, 3.06%, 4.09%, and 8.97%, respectively. The score model had acceptable discrimination with a C-statistic of 0.65 and a near-perfect moderate calibration curve (HL test p = .81). Using LASSO regression analysis, a four-risk group model was constructed, and the new model showed better discrimination in the validation cohort when compared with The Fujimoto PTLD score (C-statistic: 0.75 vs. 0.65). CONCLUSION: Our study demonstrated a more comprehensive model when compared with Fujimoto's PTLD scoring system, which included additional predictors identified through machine learning that may have enhanced discrimination. The widespread use of this promising tool for risk stratification of patients receiving HCT allows identification of high-risk patients that may benefit from preemptive treatment for PTLD. IMPLICATIONS FOR PRACTICE: This study validated the Fujimoto score for the prediction of post-transplant lymphoproliferative disorder (PTLD) development following hematopoietic cell transplant (HCT) in an external, independent, and nationally representative population. This study also developed a more comprehensive model with enhanced discrimination for better risk stratification of patients receiving HCT, potentially changing clinical managements in certain risk groups. Previously unreported risk factors associated with the development of PTLD after HCT were identified using the machine learning algorithm, least absolute shrinkage and selection operator, including pre-HCT medical history of mechanical ventilation and the chemotherapy agents used in conditioning regimen.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Trastornos Linfoproliferativos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Trastornos Linfoproliferativos/epidemiología , Trastornos Linfoproliferativos/etiología , Sistema de Registros , Proyectos de Investigación , Factores de Riesgo
15.
J Virol ; 94(22)2020 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-32817223

RESUMEN

Coronaviruses (CoV) have caused a number of major epidemics in humans and animals, including the current pandemic of coronavirus disease 2019 (COVID-19), which has brought a renewed focus on the evolution and interspecies transmission of coronaviruses. Swine acute diarrhea syndrome coronavirus (SADS-CoV), which was recently identified in piglets in southern China, is an alphacoronavirus that originates from the same genus of horseshoe bats as severe acute respiratory syndrome CoV (SARS-CoV) and that was reported to be capable of infecting cells from a broad range of species, suggesting a considerable potential for interspecies transmission. Given the importance of the coronavirus spike (S) glycoprotein in host range determination and viral entry, we report a cryo-electron microscopy (cryo-EM) structure of the SADS-CoV S trimer in the prefusion conformation at a 3.55-Å resolution. Our structure reveals that the SADS-CoV S trimer assumes an intrasubunit quaternary packing mode in which the S1 subunit N-terminal domain (S1-NTD) and the S1 subunit C-terminal domain (S1-CTD) of the same protomer pack together by facing each other in the lying-down state. SADS-CoV S has several distinctive structural features that may facilitate immune escape, such as a relatively compact architecture of the S trimer and epitope masking by glycan shielding. Comparison of SADS-CoV S with the spike proteins of the other coronavirus genera suggested that the structural features of SADS-CoV S are evolutionarily related to those of the spike proteins of the other genera rather than to the spike protein of a typical alphacoronavirus. These data provide new insights into the evolutionary relationship between spike glycoproteins of SADS-CoV and those of other coronaviruses and extend our understanding of their structural and functional diversity.IMPORTANCE In this article, we report the atomic-resolution prefusion structure of the spike protein from swine acute diarrhea syndrome coronavirus (SADS-CoV). SADS-CoV is a pathogenic alphacoronavirus that was responsible for a large-scale outbreak of fatal disease in pigs and that was reported to be capable of interspecies transmission. We describe the overall structure of the SADS-CoV spike protein and conducted a detailed analysis of its main structural elements. Our results and analyses are consistent with those of previous phylogenetic studies and suggest that the SADS-CoV spike protein is evolutionarily related to the spike proteins of betacoronaviruses, with a strong similarity in S1-NTDs and a marked divergence in S1-CTDs. Moreover, we discuss the possible immune evasion strategies used by the SADS-CoV spike protein. Our study provides insights into the structure and immune evasion strategies of the SADS-CoV spike protein and broadens the understanding of the evolutionary relationships between coronavirus spike proteins of different genera.


Asunto(s)
Alphacoronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/ultraestructura , Alphacoronavirus/genética , Secuencia de Aminoácidos , Microscopía por Crioelectrón , Evolución Molecular , Evasión Inmune , Modelos Moleculares , Alineación de Secuencia , Glicoproteína de la Espiga del Coronavirus/química , Homología Estructural de Proteína
16.
Bioorg Chem ; 114: 105150, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34328853

RESUMEN

Manoalide was studied as a potential anti-inflammatory agent for the last forty years and more than 200 publications and 180 patents were reported on this compound. However, the configurations at positions 24 and 25 and configuration-dependent bioactivity were not yet studied. In the current report, ten manoalide-like sesterterpenoids were isolated from Luffariella sp. (1-10). These stereoisomers were identified and separated for the first time since 1980 and their configurations at positions 24 and 25 were determined by analyzing their spectroscopic spectra. The configuration-dependent anti-proliferative activity of manoalide derivatives was examined by evaluating their effect on four leukemic cancer cell lines (Molt 4, K562, Sup-T1, and U937). The 24R,25S-isomers exhibited the most potent activity (IC50 0.50-7.67 µM). The anti-proliferative mechanism of action of 24R,25S-manoalide (7) was further studied on Molt 4 cells. Compound 7 exhibited apoptotic activity on Molt 4 cells through the disruption of mitochondrial membrane potential (MMP) and the generation of intracellular reactive oxygen species (ROS). It also inhibited the activity of human topoisomerase I and II. The apoptotic-inducing effect of 7 was further supported by the in vivo experiment by suppressing the volume of xenograft tumor growth (66.11%) compared with the control.


Asunto(s)
Antineoplásicos/farmacología , Sesterterpenos/farmacología , Terpenos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Sesterterpenos/síntesis química , Sesterterpenos/química , Estereoisomerismo , Relación Estructura-Actividad , Terpenos/síntesis química , Terpenos/química
17.
J Formos Med Assoc ; 120(12): 2144-2152, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33423899

RESUMEN

BACKGROUND/PURPOSE: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains the curative therapy for acute myeloid leukemia (AML) or high-risk myelodysplastic syndrome (MDS), but advanced age with multiple comorbidities limits the eligibility for allo-HSCT. We conducted a retrospective study to investigate the comorbidities assessments and prognostic factors that predict outcomes for these patients. METHODS: Clinical data of patients older than 50 years who had received diagnoses of AML or MDS and underwent allo-HSCT were obtained. Information on patient characteristics, including age, gender, allogeneic transplant type, conditioning regimens, Charlson comorbidity index (CCI), and presence of acute graft-versus-host disease (GVHD) or chronic GVHD, were collected and analyzed. RESULTS: Two hundred fifty-five elderly patients with a median age at allo-HSCT of 57 years were included. The significant prognostic factors associated with worse overall survival (OS) were CCI ≥3 (hazard ratio: 1.88) and grade III-IV acute GVHD (3.18). Similar findings were noted in the non-relapse mortality analysis. To investigate the effects of chronic GVHD on patient outcomes, OS analysis was performed for those with survival >100 days after transplantation. The results revealed CCI ≥3 (1.88) and grade III-IV acute GVHD (2.73) remained poor prognostic factors for OS, whereas mild chronic GVHD (0.43) was associated with better OS. CONCLUSION: This cohort study suggests that CCI ≥3 predicts poor outcomes, primarily due to a higher NRM risk. Careful management of GVHD after transplantation could improve outcomes in elderly patients with AML or MDS after allo-HSCT.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Anciano , Estudios de Cohortes , Comorbilidad , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Leucemia Mieloide Aguda/terapia , Síndromes Mielodisplásicos/terapia , Estudios Retrospectivos , Acondicionamiento Pretrasplante
18.
Oncologist ; 25(5): e782-e788, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31852810

RESUMEN

BACKGROUND: The discovery of effective therapeutic options for treating metastatic poorly differentiated neuroendocrine carcinoma (NEC) after prior platinum-based chemotherapy remains elusive. This study analyzed the efficacy of TLC388 (Lipotecan) Hydrochloride, a novel camptothecin analog, for pretreated patients with metastatic NEC. METHODS: This single-arm, two-stage, phase II clinical trial was conducted at four community and academic centers in Taiwan. Patients aged 20 years or older with confirmed metastatic NEC and who had received prior systemic therapy with etoposide plus cisplatin were enrolled between July 2015 and May 2018. Patients received 40 mg/m2 of TLC388 intravenously on days 1, 8, and 15 of a 28-day cycle until disease progression or unacceptable toxic effects. Gene mutations were analyzed by next-generation sequencing. RESULTS: Twenty-three patients with a median age of 61 (range, 44-73) years, 18 of whom were men (78%), were enrolled. Patients received a median of 2 (range, 0-6) treatment cycles. Among 20 evaluable patients, 3 patients exhibited stable disease and no patient experienced a complete or partial remission, resulting in a disease control rate of 15%. Median progression-free survival was 1.8 (95% confidence interval [CI], 0.4-15) months, and the median overall survival was 4.3 (95% CI, 1.7-15) months. The most common treatment-related hematologic adverse events at grade 3 or higher were leukopenia (22.7%), anemia (31.8%), and thrombocytopenia (18.2%). The most frequent mutated genes in 35 patients with NEC were ARSA, DPYD, HEXB, BRCA1, HPD, MYBPC3, BBS2, IL7R, HSD17B4, and PRODH. CONCLUSION: TLC388 demonstrates limited antitumor activity in metastatic NEC. ClinicalTrials.gov identifier: NCT02457273. IMPLICATIONS FOR PRACTICE: Poorly differentiated neuroendocrine carcinomas (NECs) are rare and aggressive. Currently, effective therapeutic options for treating metastatic poorly differentiated NECs beyond platinum-based chemotherapy remain elusive. In this single-arm, multicenter, phase II study, 23 patients with NEC were enrolled and received TLC388 (Lipotecan) Hydrochloride, which is a novel camptothecin analog. The results demonstrated the disease control rate of 15%, the median progression-free survival of 1.8 (95% confidence interval [CI], 0.4-15) months, and the median overall survival of 4.3 (95% CI, 1.7-15) months. Most importantly, several novel genetic mutations and pathways were identified. These results offer the opportunity to develop future treatment strategies in this rare cancer.


Asunto(s)
Camptotecina , Carcinoma Neuroendocrino , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Camptotecina/análogos & derivados , Camptotecina/uso terapéutico , Carcinoma Neuroendocrino/tratamiento farmacológico , Carcinoma Neuroendocrino/genética , Femenino , Genómica , Humanos , Masculino , Persona de Mediana Edad , Taiwán
19.
Bioorg Chem ; 98: 103742, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32199305

RESUMEN

Herein we present the synthesis and characterization of a novel chemical series of tadalafil analogues that display different pharmacological profiles. Compounds that have the 6R, 12aR configuration and terminal carboxylic acid group at the side chain arising from the piperazinedione nitrogen were potent PDE5 inhibitors, with compound 11 having almost equal potency to tadalafil and superior selectivity over PDE11, the most common off-target for tadalafil. Modifying the stereochemistry into 6S, 12aS configuration and adopting the hydroxamic acid moiety as a terminal group gave rise to compounds that only inhibited HDAC. Dual PDE5/HDAC inhibition could be achieved with compounds having 6R, 12aR configuration and hydroxamic acid moiety as a terminal group. The anticancer activity of the synthesized compounds was evaluated against a diverse number of cell lines of different origin. The compounds elicited anticancer activity against cell lines belonging to lymphoproliferative cancer as well as solid tumors. Despite the previous reports suggesting anticancer activity of PDE5 inhibitors, the growth inhibitory activity of the compounds seemed to be solely dependent on HDAC inhibition. Compound 26 (pan HDAC IC50 = 14 nM, PDE5 IC50 = 46 nM) displayed the most potent anticancer activity in the present series and was shown to induce apoptosis in Molt-4 cells. HDAC isoform selectivity testing for compound 26 showed that it is more selective for HDAC6 and 8 over HDAC1 by more than 20-fold.


Asunto(s)
Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5/metabolismo , Desarrollo de Medicamentos , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/metabolismo , Inhibidores de Fosfodiesterasa 5/farmacología , Tadalafilo/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Inhibidores de Histona Desacetilasas/síntesis química , Inhibidores de Histona Desacetilasas/química , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Inhibidores de Fosfodiesterasa 5/síntesis química , Inhibidores de Fosfodiesterasa 5/química , Relación Estructura-Actividad , Tadalafilo/síntesis química , Tadalafilo/química
20.
Mar Drugs ; 18(8)2020 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-32718084

RESUMEN

13-Acetoxysarcocrassolide (13-AC), a marine cytotoxic product isolated from the alcyonacean coral Lobophytum crassum, exhibited potent antitumor and immunostimulant effects as reported in previous studies. However, the 13-AC antitumor mechanism of action against oral cancer cells remains unclear. The activity of 13-AC against Ca9-22 cancer cells was determined using MTT assay, flow cytometric analysis, immunofluorescence, immunoprecipitation, Western blotting, and siRNA. 13-AC induced apoptosis in oral cancer cells Ca9-22 through the disruption of mitochondrial membrane potential (MMP) and the stimulation of reactive oxygen species (ROS) generation. It increased the expression of apoptosis- and DNA damage-related proteins in a concentration- and time-dependent manner. It exerted potent antitumor effect against oral cancer cells, as demonstrated by the in vivo xenograft animal model. It significantly reduced the tumor volume (55.29%) and tumor weight (90.33%). The pretreatment of Ca9-22 cells with N-acetylcysteine (NAC) inhibited ROS production resulting in the attenuation of the cytotoxic activity of 13-AC. The induction of the Keap1-Nrf2 pathway and the promotion of p62/SQSTM1 were observed in Ca9-22 cells treated with 13-AC. The knockdown of p62 expression by siRNA transfection significantly attenuated the effect of 13-AC on the inhibition of cell viability. Our results indicate that 13-AC exerted its cytotoxic activity through the promotion of ROS generation and the suppression of the antioxidant enzyme activity. The apoptotic effect of 13-AC was found to be mediated through the interruption of the Keap1/Nrf2/p62/SQSTM1 pathway, suggesting its potential future application as an anticancer agent.


Asunto(s)
Antineoplásicos/farmacología , Diterpenos/farmacología , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Neoplasias de la Boca/tratamiento farmacológico , Factor 2 Relacionado con NF-E2/metabolismo , Proteína Sequestosoma-1/metabolismo , Animales , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células HCT116 , Células HeLa , Humanos , Células MCF-7 , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones Desnudos , Neoplasias de la Boca/enzimología , Neoplasias de la Boca/genética , Neoplasias de la Boca/patología , Especies Reactivas de Oxígeno/metabolismo , Proteína Sequestosoma-1/genética , Transducción de Señal , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
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