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1.
Gut ; 71(8): 1656-1668, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34588223

RESUMO

OBJECTIVE: Hepatocellular carcinoma (HCC) has high intratumoral heterogeneity, which contributes to therapeutic resistance and tumour recurrence. We previously identified Prominin-1 (PROM1)/CD133 as an important liver cancer stem cell (CSC) marker in human HCC. The aim of this study was to investigate the heterogeneity and properties of Prom1+ cells in HCC in intact mouse models. DESIGN: We established two mouse models representing chronic fibrotic HCC and rapid steatosis-related HCC. We performed lineage tracing post-HCC induction using Prom1C-L/+; Rosa26tdTomato/+ mice, and targeted depletion using Prom1C-L/+; Rosa26DTA/+ mice. Single-cell RNA sequencing (scRNA-seq) was carried out to analyse the transcriptomic profile of traced Prom1+ cells. RESULTS: Prom1 in HCC tumours marks proliferative tumour-propagating cells with CSC-like properties. Lineage tracing demonstrated that these cells display clonal expansion in situ in primary tumours. Labelled Prom1+ cells exhibit increasing tumourigenicity in 3D culture and allotransplantation, as well as potential to form cancers of differential lineages on transplantation. Depletion of Prom1+ cells impedes tumour growth and reduces malignant cancer hallmarks in both HCC models. scRNA-seq analysis highlighted the heterogeneity of Prom1+ HCC cells, which follow a trajectory to the dedifferentiated status with high proliferation and stem cells traits. Conserved gene signature of Prom1 linage predicts poor prognosis in human HCC. The activated oxidant detoxification underlies the protective mechanism of dedifferentiated transition and lineage propagation. CONCLUSION: Our study combines in vivo lineage tracing and scRNA-seq to reveal the heterogeneity and dynamics of Prom1+ HCC cells, providing insights into the mechanistic role of malignant CSC-like cells in HCC progression.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Antígeno AC133/genética , Antígeno AC133/uso terapêutico , Animais , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Camundongos , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/patologia , Análise de Célula Única
2.
Luminescence ; 36(1): 237-246, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32841473

RESUMO

(Ca1-x Eux )WO4 (x = 0-21 mol%) phosphors were prepared using the classical solid-state reaction method. The influence of Eu3+ ion doping on lattice structure was observed using powder X-ray diffraction and Fourier transform infrared spectroscopy. Furthermore, under this influence, the luminescence properties of all samples were analyzed. The results clearly illustrated that the element europium was successfully incorporated into the CaWO4 lattice with a scheelite structure in the form of a Eu3+ ion, which introduced a slight lattice distortion into the CaWO4 matrix. These lattice distortions had no effect on phase purity, but had regular effects on the intrinsic luminescence of the matrix and the f-f excitation transitions of Eu3+ activators. When the Eu3+ concentration was increased to 21 mol%, a local luminescence centre of [WO4 ]2- groups was detected in the matrix and manifested as the decay curves of [WO4 ]2- groups and luminescence changed from single exponential to double exponential fitting. Furthermore, the excitation transitions of Eu3+ between different energy levels (such as 7 F0 →5 L6 , 7 F0 →5 D2 ) also produced interesting changes. Based on analysis of photoluminescence spectra and the chromaticity coordinates in this study, it could be verified that the nonreversing energy transfer of [WO4 ]2- →Eu3+ was efficient and incomplete.


Assuntos
Európio , Luminescência , Transferência de Energia , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
3.
Luminescence ; 35(4): 580-585, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31898376

RESUMO

Dy3+ -doped Y3 Al5 O12 phosphors were prepared at a relatively low temperature using molten salt synthesis. The phase of the prepared Dy3+ -doped Y3 Al5 O12 phosphors was confirmed using X-ray powder diffraction. Results indicated that Dy3+ doping did not change the Y3 Al5 O12 phase. Following excitation at 352 nm, emission spectra of the Dy3+ -doped Y3 Al5 O12 phosphors consisted of blue, yellow, and red emission bands. The influence of Dy3+ concentration and excitation wavelength on emission was investigated. The ratio of yellow light to blue light varied with change in Dy3+ doping concentration, due to changes in the structure around Dy3+ . Emission intensities also changed when the excitation wavelength was changed. This variation is luminescence generated a system for tunable white light for Dy3+ -doped Y3 Al5 O12 phosphors.


Assuntos
Óxido de Alumínio/química , Disprósio/química , Luminescência , Substâncias Luminescentes/química , Ítrio/química , Substâncias Luminescentes/síntese química , Difração de Pó , Sais/síntese química , Sais/química
4.
J Clin Invest ; 131(11)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33878034

RESUMO

Rapidly growing tumors often experience hypoxia and nutrient (e.g., glucose) deficiency because of poor vascularization. Tumor cells respond to the cytotoxic effects of such stresses by inducing molecular adaptations that promote clonal selection of a more malignant tumor-initiating cell phenotype, especially in the innermost tumor regions. Here, we report a regulatory mechanism involving fucosylation by which glucose restriction promotes cancer stemness to drive drug resistance and tumor recurrence. Using hepatocellular carcinoma (HCC) as a model, we showed that restricted glucose availability enhanced the PERK/eIF2α/ATF4 signaling axis to drive fucosyltransferase 1 (FUT1) transcription via direct binding of ATF4 to the FUT1 promoter. FUT1 overexpression is a poor prognostic indicator for HCC. FUT1 inhibition could mitigate tumor initiation, self-renewal, and drug resistance. Mechanistically, we demonstrated that CD147, ICAM-1, EGFR, and EPHA2 are glycoprotein targets of FUT1, in which such fucosylation would consequently converge on deregulated AKT/mTOR/4EBP1 signaling to drive cancer stemness. Treatment with an α-(1,2)-fucosylation inhibitor sensitized HCC tumors to sorafenib, a first-line molecularly targeted drug used for advanced HCC patients, and reduced the tumor-initiating subset. FUT1 overexpression and/or CD147, ICAM-1, EGFR, and EPHA2 fucosylation may be good prognostic markers and therapeutic targets for cancer patients.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/enzimologia , Fucosiltransferases/metabolismo , Glucose/metabolismo , Neoplasias Hepáticas Experimentais/enzimologia , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/enzimologia , Animais , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Fucosiltransferases/genética , Glucose/farmacologia , Glicosilação , Células Hep G2 , Humanos , Neoplasias Hepáticas Experimentais/diagnóstico , Neoplasias Hepáticas Experimentais/genética , Camundongos , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/patologia , Prognóstico , Galactosídeo 2-alfa-L-Fucosiltransferase
5.
Cancer Lett ; 476: 48-56, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32061952

RESUMO

Solid evidence shows that tumor-initiating cells (T-ICs) are the root of tumor relapse and drug resistance, which lead to a poor prognosis in patients with hepatocellular carcinoma (HCC). Through an in vitro liver T-IC enrichment approach, we identified nuclear factor (erythroid-derived 2)-like 2 (NRF2) as a transcription regulator that is significantly activated in enriched liver T-IC populations. In human HCCs, NRF2 was found to be overexpressed, which was associated with poor patient survival. Through a lentiviral based knockdown approach, NRF2 was found to be critical for regulating liver T-IC properties, including self-renewal, tumorigenicity, drug resistance and expression of liver T-IC markers. Furthermore, we found that ROS-induced NRF2 activation regulates sorafenib resistance in HCC cells. Mechanistically, NRF2 was found to physically bind to the promoter of sonic hedgehog homolog (SHH), which triggers activation of the sonic hedgehog pathway. The effect of NRF2 knockdown was eliminated upon administration of recombinant SHH, demonstrating that NRF2 mediated T-IC function via upregulation of SHH expression. Our study suggests a novel regulatory mechanism for the canonical sonic hedgehog pathway that may function through the NRF2/SHH/GLI signaling axis, thus mediating T-IC phenotypes.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas Hedgehog/metabolismo , Neoplasias Hepáticas/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Células-Tronco Neoplásicas/patologia , Animais , Antineoplásicos/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Linhagem da Célula , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Proteínas Hedgehog/genética , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Fator 2 Relacionado a NF-E2/genética , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/metabolismo , Prognóstico , Sorafenibe/farmacologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Beilstein J Nanotechnol ; 10: 1237-1242, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293861

RESUMO

Tb2.96- x Ce0.04GdxAl5O12 phosphors were synthesized through solid-state reactions. The influence of Gd3+ on the luminescence was investigated. Under the excitation at 460 nm, Tb2.96Ce0.04Al5O12 shows the characteristic emission band of Ce3+ with a peak wavelength at about 554 nm. After co-doping Gd3+ into Tb2.96Ce0.04Al5O12, the peak wavelength of the Ce3+ emission band shifts to longer wavelengths, which is induced by the increasing crystal field splitting. However, the Ce3+ emission intensity also decreases because the substitution of Tb3+ with Gd3+ causes lattice deformation and generates numerous structural and chemical defects. By comparing the light parameters of white light-emitting diodes (WLEDs) containing Y2.96Ce0.04Al5O12, Tb2.96Ce0.04Al5O12 and Tb2.81Ce0.04Gd0.15Al5O12 phosphors, we can find that the WLED containing the Tb2.81Ce0.04Gd0.15Al5O12 phosphor generates warmer light than the WLEDs containing Y2.96Ce0.04Al5O12 and Tb2.96Ce0.04Al5O12 phosphors. Moreover, the WLEDs fabricated by integrating a blue LED chip and Ce3+/Gd3+-co-doped Tb3Al5O12 phosphors show outstanding colour stability when driven under different currents.

8.
Oncotarget ; 6(20): 18151-61, 2015 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-26061709

RESUMO

OBJECTIVES: Major adjuvant therapies (ATs) for resected hepatocellular carcinoma (HCC) include chemotherapy, internal radiation therapy (IRT), interferon therapy (IFNT) and immunotherapy but the optimum regimen remains inconclusive. We aim to compare these therapies in terms of patient survival and recurrence rates. METHODS: We searched PubMed, EMBASE and Cochrane library databases for randomized trials comparing the above four therapies until 31 March 2014. We estimated the HRs for survival and ORs for overall recurrence among different therapies. Toxic effects were also evaluated. RESULTS: Fourteen eligible articles were included. IFNT improved 5-year survival greatly (HR 1.81, 95% CI 1.01-3.81, P = 0.034), whereas chemotherapy (HR 0.33, 95% CI 0.03-2.02), IRT (HR 0.31, 95% CI 0.02-3.33) and immunotherapy (HR 0.73, 95% CI 0.05-9.12) all provided a poorer survival outcome after 1-year. Similarly, for 5-year survival rates, although differing, IRT did not provide a significant improvement in survival (HR 1.38, 95% CI 0.34-5.19) compared with IFNT. Chemotherapy (HR 0.49, 95% CI 0.18-1.14) and immunotherapy (HR 0.56, 95% CI 0.17-1.59) did not appear to provide benefit over IFNT. Chemotherapy was ranked the worst in overall recurrence (OR 0.99, 95% CI 0.18-5.38) and most likely to cause toxic effects. CONCLUSIONS: IFNT was the most efficacious AT regimen both for short and long term survivals. Immunotherapy and IFNT were the most two effective in preventing overall relapse for resected HCC.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/terapia , Imunoterapia/métodos , Interferons/uso terapêutico , Neoplasias Hepáticas/terapia , Antineoplásicos/efeitos adversos , Teorema de Bayes , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Quimioterapia Adjuvante , Progressão da Doença , Intervalo Livre de Doença , Hepatectomia , Humanos , Imunoterapia/efeitos adversos , Imunoterapia/mortalidade , Interferons/efeitos adversos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Cadeias de Markov , Método de Monte Carlo , Recidiva Local de Neoplasia , Razão de Chances , Radioterapia Adjuvante , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
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