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1.
Acta Pharmacol Sin ; 45(4): 857-866, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38200149

RESUMEN

HER3 (human epidermal growth factor receptor 3) acts through heterodimerization with EGFR (epidermal growth factor receptor) or HER2 to play an essential role in activating phosphoinositide 3-kinase (PI3K) and AKT signaling-a crucial pathway that promotes tumor cell survival. HER3 is a promising target for cancer therapy, and several HER3-directed antibodies have already entered into clinical trials. In this study we characterized a novel anti-HER3 monoclonal antibody, SIBP-03. SIBP-03 (0.01-10 µg/mL) specifically and concentration-dependently blocked both neuregulin (NRG)-dependent and -independent HER3 activation, attenuated HER3-mediated downstream signaling and inhibited cell proliferation. This antitumor activity was dependent, at least in part, on SIBP-03-induced, cell-mediated cytotoxicity and cellular phagocytosis. Importantly, SIBP-03 enhanced the antitumor activity of EGFR- or HER2-targeted drugs (cetuximab or trastuzumab) in vitro and in vivo. The mechanisms underlying this synergy involve increased inhibition of HER3-mediated downstream signaling. Collectively, these results demonstrated that SIBP-03, which is currently undergoing a Phase I clinical trial in China, may offer a new treatment option for patients with cancers harboring activated HER3, particularly as part of a combinational therapeutic strategy.


Asunto(s)
Anticuerpos Monoclonales , Antineoplásicos , Neoplasias , Receptor ErbB-3 , Humanos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Fosfatidilinositol 3-Quinasas/metabolismo , Receptor ErbB-2/metabolismo , Receptor ErbB-3/antagonistas & inhibidores , Receptor ErbB-3/metabolismo , Transducción de Señal , Trastuzumab/farmacología , Trastuzumab/uso terapéutico , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/uso terapéutico , Neoplasias/terapia
2.
Clin Oral Implants Res ; 34(7): 698-706, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37183773

RESUMEN

OBJECTIVES: Dental implants with a triangular neck design have been developed in order to maintain peri-implant bone. The primary aim of this randomized controlled trial (RCT) was to assess after 5 years the peri-implant bone stability and the peri-implant soft tissue conditions with this new triangular implant neck design compared to a conventional round neck implant design. MATERIAL AND METHODS: This is a secondary evaluation of a RCT including 34 patients. Patients were recalled after 1, 3, and finally 5 years to assess implant survival and peri-implant bone levels using standardized radiographs. Peri-implant soft tissue health was also evaluated by recording probing depth, plaque index and Bleeding on Probing. Patient Reported Outcome Measures (PROMs) and the Pink Esthetic Score were also assessed. RESULTS: No implant loss occurred during the 5-year follow up period. The mean ± SD proximal bone remodeling after 5 years reached 0.38 ± 0.39 mm for the circular design and 0.29 ± 0.58 mm for the triangular design (p = .49). Peri-implant soft tissue health parameters and PROMs were found to be comparable. Altogether, 80% of implants presented peri-implant mucositis whereas one implant (4%) displayed sings of peri-implantitis. CONCLUSION: The 5-year evaluation of the triangular neck implants showed similar results to the circular neck implants.


Asunto(s)
Implantes Dentales , Periimplantitis , Humanos , Estudios de Seguimiento , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Radiografía
3.
Biomed Chromatogr ; 37(2): e5541, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36328792

RESUMEN

In this study, deep eutectic solvent (DES), as a new green solvent, was used to extract bioactive alkaloids from Ephedrae Herba using supersonic extraction. In a variety of tested hydrophilic and hydrophobic DESs, DES composed of choline chloride and xylitol was proved to be the most efficient solvent. Factors affecting extraction efficiency, including the mole ratio of hydrogen bond acceptor/hydrogen bond donor, water contention, and solid/liquid ratio, were optimized individually. Under optimal conditions, the yield of ephedrine (EP) and pseudoephedrine obtained using this new method was 14.24 and 4.32 mg/g, respectively, which was higher than that using the traditional solvent (acidified water and methanol). Furthermore, the extraction mechanism of DES and EP was investigated using molecular dynamics simulation study. Structural properties such as radial distribution functions and average number of hydrogen bonds were then computed. The results showed that hydrogen bonds and van der Waals forces are important driving forces of extraction; in addition, the hydrogen bonds between the Cl atom of choline chloride and N atom of EP played a dominant part in the extraction process. Based on the extraction principle, the extraction method using choline chloride as extraction solvent was also discussed.


Asunto(s)
Alcaloides , Disolventes Eutécticos Profundos , Efedrina , Colina , Disolventes Eutécticos Profundos/química , Efedrina/análogos & derivados , Efedrina/química , Solventes/química , Agua/química
4.
Nano Lett ; 22(18): 7644-7650, 2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36103637

RESUMEN

Nanoparticle self-assembly enables the generation of complex ordered nanostructures with enhanced properties or new functionalities. However, the ordering is often limited to the micrometer scale with chemical strategies due to the relative weak supramolecular interactions that govern the self-assembly process. Here a physical strategy via temperature-gradient-assisted self-assembly is reported to create three-dimensional (3D) macroscopic ordered nanocomposites with different gradient variations in grain size, constituent content, and crystal orientation. The resulting α-Fe/Pr2Fe14B ordered nanostructure with reverse gradients in both the grain size and α-Fe content exhibits a record-high energy density of about 25 MGOe for isotropic α-Fe/Pr2Fe14B systems, approximately 130% higher than that of its disordered counterpart. Both experiments and micromagnetic simulations demonstrate that creating ordered nanostructures is an alternative approach to develop high-performance permanent-magnet materials. Our findings make a significant step toward creating 3D macroscopic ordered nanostructures and will stimulate the development of ordered nanomaterials.

5.
J Org Chem ; 87(5): 3596-3604, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35147433

RESUMEN

The multicomponent-multicatalyst reaction ((MC)2R) and visible-light catalysis have emerged as green and powerful strategies for achieving ideal syntheses. Here, we report the first example of a visible-light-induced approach toward spiroquinazolin(thi)ones. This (MC)2R features an eco-friendly energy source and solvent, metal-free catalysts, step- and atom-economy, a relay catalysis strategy, air as green oxidant, mild conditions, and easily accessible starting materials.

6.
Phytother Res ; 36(3): 1353-1371, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35112410

RESUMEN

Cumulative evidence indicates that mitochondria dysfunction plays an important role in tumour treatment. Given the limited efficacy and toxicity of current mitochondria-targeted drugs, research into effective mitochondria-targeted anticancer agents remains an irresistible general trend. In this study, it was found that dehydrocrenatidine (DEC), a ß-carbolin alkaloid isolated from Picrasma quassiodes, displays a promising growth inhibitory effect in vitro and in vivo by inducing apoptosis of hepatocellular carcinoma (HCC) cells. Mechanistically, we provided that the possible target of DEC against HCC cells was determined by isobaric labels for relative and absolute quantification assay and validated them using further experiments. The results suggested that DEC can target and regulate the function of mitochondrial complexes I, III and IV, affecting oxidative phosphorylation and ultimately leading to mitochondrial dysfunction to exert its anti-HCC effects. In addition, the combination of DEC and sorafenib showed a synergistic effect and was also associated with mitochondrial dysfunction. Importantly, DEC did not show significant toxicity in mice. This study provided a new insight into underlying mechanisms in DEC-treated HCC cells, suggesting that DEC might be a mitochondrial targeting lead compound.


Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis , Carbolinas , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Ratones , Mitocondrias
7.
Int J Comput Dent ; 25(1): 83-98, 2022 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-35322655

RESUMEN

AIM: The objective of the present case series was to evaluate the 4-year outcomes of implants placed in the esthetic area using static computer-assisted implant surgery (s-CAIS) and restored with a one-abutment one-time (OAOT) protocol using custom-made zirconia abutments and cemented provisional crowns manufactured prior to surgery. Materials and methods: Ten consecutive implants were placed in the esthetic area. Based on a digital implant and prosthodontic planning, surgical guides were ordered and used for the preparation of definitive custom-made zirconia abutments and polymethylmethacrylate provisional crowns. Implants were placed using the s-CAIS guide, and prosthetic components were placed immediately. Implant outcomes were evaluated at the time of surgery, after 4 months, and after 4 years. RESULTS: All implants were successfully placed with s-CAIS and restored with final abutments and provisional crowns. No major prosthetic adverse events were observed. After 4 years, the implant survival rate was 100%, minor peri-implant bleeding on probing was reported, and very stable peri-implant bone levels were observed. The pink esthetic score showed that the prosthetic components were well integrated, and the peri-implant soft tissue was stable. CONCLUSIONS: Within the limitations of the present case series, these results suggest that emerging digital workflows allow the manufacture of final custom-made abutments and provisional crowns prior to surgery. This individualized OAOT procedure may reduce cement-related complications and improve esthetic outcomes by optimizing soft tissue healing with prosthetic components. However, such protocols have evolved toward fully digital workflows, and comparative clinical trials are needed.


Asunto(s)
Pilares Dentales , Estética Dental , Coronas , Materiales Dentales , Estudios de Seguimiento , Humanos
8.
Acta Pharmacol Sin ; 42(1): 132-141, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32404982

RESUMEN

Hsp90 is a potential therapeutic target for tumor, as it maintains the stability of a variety of proteins related to tumor development and progression. Autophagy is a self-degradation process to maintain cellular homeostasis and autophagy inhibitors can suppress tumor growth. In this study, we identified DCZ5248, a triazine derivative, was a dual inhibitor of both Hsp90 and late-autophagy with potent antitumor activity against colon cancer cells in vitro and in vivo. We showed that DCZ5248 (0.1-10 µM) induced dose-dependent degradation of Hsp90 client proteins (AKT, CDK4, CDK6 and RAF-1) in HCT 116 colon cancer cells through a proteasome-dependent pathway. Meanwhile, DCZ5248 (0.3 µM) induced cytoplasmic vacuole formation, LC3 II conversion, p62 protein upregulation, and inhibited autophagy at the late stage in the colon cancer cell lines tested. We further revealed that the inhibition of autophagy was achieved by impairing lysosomal functions through induction of lysosomal acidification and attenuation of lysosomal cathepsin activity. The modulation of autophagy by DCZ5248 was independent of Hsp90 inhibition as the autophagy inhibition was not blocked by Hsp90 knockdown. Importantly, inhibition of both Hsp90 function and autophagy by DCZ5248 induced G1-phase cell cycle arrest, apoptosis, and exerted potent antitumor activity against colon cancer cells both in vitro and in vivo. These findings demonstrate that DCZ5248 is a novel dual inhibitor of Hsp90 and autophagy with potential for colon cancer therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Autofagia/efectos de los fármacos , Neoplasias del Colon/tratamiento farmacológico , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Triazinas/uso terapéutico , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Lisosomas/efectos de los fármacos , Ratones Endogámicos BALB C , Ensayos Antitumor por Modelo de Xenoinjerto
9.
BMC Infect Dis ; 20(1): 961, 2020 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-33334317

RESUMEN

BACKGROUND: The clinical characteristics of patients with confirmed 2019 novel coronavirus disease (COVID-19) in Jilin Province, China were investigated. METHODS: Clinical, laboratory, radiology, and treatment data of 41 hospitalized patients with confirmed COVID-19 were retrospectively collected. The population was stratified by disease severity as mild, moderate, or severe, based on guidelines of the National Health and Medical Commission of China. RESULTS: The 41 hospitalized patients with COVID-19 were studied, and the median age was 45 years (interquartile range [IQR], 31-53; range, 10-87 years) and 18 patients (43.9%) were female. All of the patients had recently visited Wuhan or other places (ie, Beijing, Thailand) or had Wuhan-related exposure. Common symptoms included fever (32[78%]) and cough (29[70.7%]). All patients were without hepatitis B/C virus hepatitis. CRP (C-reactive protein, 11.3 mg/L [interquartile range {IQR}, 2.45-35.2]) was elevated in 22 patients (53.7%), and cardiac troponin I (1.5 ng/mL [IQR, 0.8-5.0]) was elevated in 41 patients (100%). Chest computed tomographic scans showed bilateral ground glass opacity (GGO) or GGO with consolidation in the lungs of 27(65.9%) patients. 31(75.6%) patients had an abnormal electrocardiograph (ECG). Comparing the three groups, the levels of CRP and cardiac troponin I, GGO distribution in bilateral lungs, and electrocardiogram changes were statistically significant (p < 0.05). Cardiac troponin I had a strong positive correlation with CRP (r = 0.704, p = 0.042) and LDH (r = 0.738, p = 0.037). CONCLUSION: Significant differences among the groups suggest that several clinical parameters may serve as biomarkers of COVID-19 severity at hospital admission. Elevated cTnI could be considered as a predictor of severe COVID-19, reflecting the prognosis of patients with severe COVID-19. The results warrant further inspection and confirmation.


Asunto(s)
COVID-19/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , COVID-19/epidemiología , COVID-19/patología , COVID-19/fisiopatología , Niño , China/epidemiología , Femenino , Corazón/fisiopatología , Hospitalización , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Masculino , Persona de Mediana Edad , Neumonía Viral/diagnóstico , Neumonía Viral/epidemiología , Neumonía Viral/patología , Neumonía Viral/fisiopatología , Pronóstico , Estudios Retrospectivos , SARS-CoV-2 , Adulto Joven
10.
Bioorg Chem ; 96: 103650, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32044515

RESUMEN

In the current study, four pairs of new enantiomeric alkaloids (1a/1b-4a/4b) were obtained from the leaves of Isatis indigotica Fortune Ex Land. Their structures were elucidated through spectroscopic methods and quantum mechanical calculations. Biologically, all isolates were evaluated for their neuroprotective effects against H2O2-induced SH-SY5Y cell injury. As a result, 1a and 1b exhibited enantioselective neuroprotective effects, further Annexin V-FITC/PI analysis showed that apoptosis ratios of 1a and 1b were reduced to 20.93% and 17.87%, respectively.


Asunto(s)
Alcaloides/farmacología , Peróxido de Hidrógeno/metabolismo , Isatis/química , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Alcaloides/química , Apoptosis/efectos de los fármacos , Línea Celular , Humanos , Neuronas/citología , Neuronas/metabolismo , Fármacos Neuroprotectores/química , Hojas de la Planta/química , Estereoisomerismo
11.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(10): 1119-1124, 2020 Oct.
Artículo en Zh | MEDLINE | ID: mdl-33059811

RESUMEN

OBJECTIVE: To study the expression of angiotensin-converting enzyme 2 (ACE2) and other key molecules of the RAS pathway in normal mice at different developmental stages, and to provide ideas for understanding the infection mechanism of coronavirus disease 2019 (COVID-19) as well as the diagnosis and treatment of children with COVID-19. METHODS: The mice at different developmental stages were enrolled, including fetal mice (embryonic days 14.5 and 18.5), neonatal mice (0, 3, 7, 14, and 21 days old), young mice (28 and 42 days old), and adult mice (84 days old). The lung tissues of all fetal mice from 4 pregnant mice were collected at each time point in the fetal group. Four mice were sampled in other age groups at each time point. Whole transcriptome resequencing was used to measure the mRNA expression of AGT, ACE, ACE2, Renin, Agtr1a, Agtr1b, Agtr2, and Mas1 in mouse lung tissue. RESULTS: The expression of ACE2 in the lungs showed changes from embryonic stage to adult stage. It increased gradually after birth, reached a peak on day 3 after birth, and reached a nadir on day 14 after birth (P<0.05). The expression of AGT reached a peak on days 0 and 7 after birth and reached a nadir on day 21 after birth (P<0.05). The expression of ACE increased rapidly after birth and reached a peak on day 21 after birth (P<0.05). Agtr1a expression reached a peak on day 21 after birth (P<0.05). Agtr2 expression gradually decreased to a low level after birth. Renin, Agtr1b, and Mas1 showed low expression in lung tissues at all developmental stages. CONCLUSIONS: At different developmental stages of mice, ACE2 has dynamic expression changes, with high expression in early neonatal and adult mice. The other key molecules of the RAS pathway have their own expression patterns. These suggest that the difference in clinical features between children and adults with COVID-19 might be associated with the different expression levels of ACE2 in the different stages, and further studies are needed for the mechanism.


Asunto(s)
Factores de Edad , Infecciones por Coronavirus/patología , Peptidil-Dipeptidasa A/metabolismo , Neumonía Viral/patología , Enzima Convertidora de Angiotensina 2 , Animales , Animales Recién Nacidos , Betacoronavirus , COVID-19 , Femenino , Feto , Pulmón/metabolismo , Pulmón/virología , Ratones , Pandemias , Embarazo , Proto-Oncogenes Mas , Sistema Renina-Angiotensina , SARS-CoV-2
12.
J Am Chem Soc ; 141(17): 6812-6816, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30998329

RESUMEN

A 17-membered macrocyclolipopeptide, named dysoxylactam A (1) comprising an unprecedented branched C19 fatty acid and an l-valine, was isolated from the plants of Dysoxylum hongkongense. The challenging relative configuration of 1 was established by means of residual dipolar coupling-based NMR analysis. The absolute configuration of 1 was determined by single-crystal X-ray diffraction on its p-bromobenzoate derivative (2). Compound 1 dramatically reversed multidrug resistance in cancer cells with the fold-reversals ranging from 28.4 to 1039.7 at the noncytotoxic concentration of 10 µM. The mode-of-action study of 1 revealed that it inhibited the function of P-glycoprotein (P-gp), a key mediator in multidrug resistance.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Antineoplásicos/farmacología , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Lipopéptidos/farmacología , Péptidos Cíclicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/aislamiento & purificación , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Lipopéptidos/síntesis química , Lipopéptidos/química , Lipopéptidos/aislamiento & purificación , Meliaceae/química , Péptidos Cíclicos/síntesis química , Péptidos Cíclicos/aislamiento & purificación
13.
Org Biomol Chem ; 17(9): 2564, 2019 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-30768080

RESUMEN

Correction for 'Bioactive spiropyrrolizidine oxindole alkaloid enantiomers from Isatis indigotica fortune' by Si-Fan Liu et al., Org. Biomol. Chem., 2018, 16, 9430-9439.

14.
Bioorg Chem ; 88: 102926, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31005021

RESUMEN

A pair of new cycloneolignan enantiomers (1a and 1b) were isolated from the leaves of Isatis indigotica Fortune. Their structures were elucidated by extensive spectroscopic data analysis, including 1D and 2D NMR, HRESIMS, MS/MS analysis, together with theoretical electronic circular dichroism (ECD) calculations. Compounds 1a and 1b were then evaluated for their neuroprotective effects against MPP+-induced SH-SY5Y cell injury. As a result, compounds 1a (77.64%) and 1b (78.62%) exhibited moderate neuroprotective activity at the concentration of 12.5 µM compared with that of MPP+ treated group (62.00% at 1 mM) by MTT assay. Furthermore, Annexin V-FITC/PI analysis showed that apoptosis ratios of 1a and 1b were reduced to 10.99% and 9.31%, respectively.


Asunto(s)
1-Metil-4-fenilpiridinio/antagonistas & inhibidores , Descubrimiento de Drogas , Isatis/química , Lignanos/farmacología , Fármacos Neuroprotectores/farmacología , 1-Metil-4-fenilpiridinio/farmacología , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Lignanos/química , Lignanos/aislamiento & purificación , Estructura Molecular , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/aislamiento & purificación , Hojas de la Planta/química , Estereoisomerismo , Relación Estructura-Actividad , Células Tumorales Cultivadas
16.
Acta Pharmacol Sin ; 40(7): 971-979, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30643210

RESUMEN

Emerging evidence demonstrates that a c-Met antibody-drug conjugate (ADC) has superior efficacy and safety profiles compared with those of currently available small molecules or antibody inhibitors for the treatment of c-Met-overexpressing cancers. Here we described both the in vitro and in vivo efficacies of SHR-A1403, a novel c-Met ADC composed of a humanized IgG2 monoclonal antibody against c-Met conjugated to a novel cytotoxic microtubule inhibitor. SHR-A1403 showed high affinity to c-Met proteins derived from human or monkey and potent inhibitory effects in cancer cell lines with high c-Met protein expression. In mice bearing tumors derived from cancer cell lines or patient HCC tissues with confirmed c-Met overexpression, SHR-A1403 showed excellent anti-tumor efficacy. Antibody binding with c-Met contributed to SHR-A1403 endocytosis; the subsequent translocation to lysosomes and cytotoxicity of the released toxin are speculated to be predominant mechanisms underlying the anti-tumor activity of SHR-A1403. In conclusion, SHR-A1403 showed significant anti-tumor activity in cancer cell lines, xenograft mouse models and an HCC PDX model, which all have high c-Met levels. These data provide references for SHR-A1403 as a potential therapy for the treatment of cancers with c-Met overexpression.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Inmunoconjugados/uso terapéutico , Neoplasias Hepáticas/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Moduladores de Tubulina/uso terapéutico , Animales , Anticuerpos Monoclonales Humanizados/inmunología , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/toxicidad , Antineoplásicos/inmunología , Antineoplásicos/toxicidad , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Humanos , Inmunoconjugados/inmunología , Inmunoconjugados/toxicidad , Macaca fascicularis , Masculino , Ratones Endogámicos BALB C , Microtúbulos/efectos de los fármacos , Proteínas Proto-Oncogénicas c-met/inmunología , Moduladores de Tubulina/inmunología , Moduladores de Tubulina/toxicidad , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Acta Pharmacol Sin ; 40(2): 268-278, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29777202

RESUMEN

BRAF and MEK inhibitors have shown remarkable clinical efficacy in BRAF-mutant melanoma; however, most patients develop resistance, which limits the clinical benefit of these agents. In this study, we found that the human melanoma cell clones, A375-DR and A375-TR, with acquired resistance to BRAF inhibitor dabrafenib and MEK inhibitor trametinib, were cross resistant to other MAPK pathway inhibitors. In these resistant cells, phosphorylation of ribosomal protein S6 (rpS6) but not phosphorylation of ERK or p90 ribosomal S6 kinase (RSK) were unable to be inhibited by MAPK pathway inhibitors. Notably, knockdown of rpS6 in these cells effectively downregulated G1 phase-related proteins, including RB, cyclin D1, and CDK6, induced cell cycle arrest, and inhibited proliferation, suggesting that aberrant modulation of rpS6 phosphorylation contributed to the acquired resistance. Interestingly, RSK inhibitor had little effect on rpS6 phosphorylation and cell proliferation in resistant cells, whereas P70S6K inhibitor showed stronger inhibitory effects on rpS6 phosphorylation and cell proliferation in resistant cells than in parental cells. Thus regulation of rpS6 phosphorylation, which is predominantly mediated by BRAF/MEK/ERK/RSK signaling in parental cells, was switched to mTOR/P70S6K signaling in resistant cells. Furthermore, mTOR inhibitors alone overcame acquired resistance and rescued the sensitivity of the resistant cells when combined with BRAF/MEK inhibitors. Taken together, our findings indicate that RSK-independent phosphorylation of rpS6 confers resistance to MAPK pathway inhibitors in BRAF-mutant melanoma, and that mTOR inhibitor-based regimens may provide alternative strategies to overcome this acquired resistance.


Asunto(s)
Resistencia a Antineoplásicos/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Proteína S6 Ribosómica/metabolismo , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Línea Celular Tumoral , Humanos , Imidazoles/farmacología , Melanoma/tratamiento farmacológico , Melanoma/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Mutación , Oximas/farmacología , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Proteínas Proto-Oncogénicas B-raf/genética , Piridonas/farmacología , Pirimidinonas/farmacología
18.
Planta Med ; 85(17): 1374-1382, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31801158

RESUMEN

Six pairs of alkaloid enantiomers including 11 new alkaloids (1A: /1B: -5A: /5B, 6A: ) were isolated from the leaves of Isatis tinctoria. Their structures were established by extensive spectroscopic analyses. Enantiomers were separated successfully by chiral chromatographic column and the absolute configurations of all isolates were determined by comparison of experimental and calculated electronic circular dichroism spectra. The isolated alkaloids were evaluated for their neuroprotective activities against H2O2-induced cell injury in human neuroblastoma SH-SY5Y cells. The results showed that 5A/5B: and 6A/6B: exhibited potent neuroprotective activities at 50 µM compared with the H2O2-treated group.


Asunto(s)
Isatis/química , Fármacos Neuroprotectores/farmacología , Extractos Vegetales/farmacología , Línea Celular Tumoral , Humanos , Peróxido de Hidrógeno , Isomerismo , Estructura Molecular , Neuroblastoma , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/aislamiento & purificación , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación
19.
J Asian Nat Prod Res ; 21(1): 51-61, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29063792

RESUMEN

A series of E-ring lactone-opened camptothecin (CPT) derivatives bearing with terminal aza-heterocyclic groups were synthesized, and their antitumor activity was evaluated both in vitro and in vivo. Hydroxyl-amide analogues with morpholin-4-yl displayed excellent antitumor activity in vitro and efficient inhibition on tumor xenograph model in nude mice. Ester-amide compounds acted less active in vitro cytotoxicity and lower inhibition activity in vivo. Substitutions at 7- and 10- positions favored the antitumor activity.


Asunto(s)
Antineoplásicos Fitogénicos/síntesis química , Camptotecina/análogos & derivados , Animales , Antineoplásicos Fitogénicos/farmacología , Camptotecina/síntesis química , Línea Celular Tumoral , Humanos , Ratones , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Small ; 14(22): e1800619, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29718577

RESUMEN

The precise control of individual components in multicomponent nanostructures is crucial to realizing their fascinating functionalities for applications in electronics, energy-conversion devices, and biotechnologies. However, this control remains particularly challenging for bulk, multicomponent nanomaterials because the desired structures of the constitute components often conflict. Herein, a strategy is reported for simultaneously controlling the structural properties of the constituent components in bulk multicomponent nanostructures through layered structural design. The power of this approach is illustrated by generating the desired structures of each constituent in a bulk multicomponent nanomaterial (SmCo + FeCo)/NdFeB, which cannot be attained with existing methods. The resulting nanostructure exhibits a record high energy density (31 MGOe) for this class of bulk nanocomposites composed of both hard and soft magnetic materials, with the soft magnetic fraction exceeding 20 wt%. It is anticipated that other properties beyond magnetism, such as the thermoelectric and mechanical properties, can also be tuned by engineering such layered architectures.

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