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1.
Zookeys ; 1197: 197-213, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38666072

RESUMO

A new species of gekkonid, Hemiphyllodactylusgengmaensissp. nov., is described based on six specimens from Gengma Dai and Wa Autonomous County, Yunnan, China. The new species can be distinguished from its congeners by a significant genetic divergence of greater than 9.7% in the mitochondrial ND2 gene and a combination of the following characters: a maximum SVL of 43.24mm; 8 or 9 chin scales; six circumnasal scales; 2 or 3 internasal scales; 9-11 supralabial scales; 8 or 9 infralabial scales; 11-18 dorsal scales; 8-10 ventral scales; a manual lamellar formula of 5-5-5-4 or 5-6-5-4 and a pedal lamellar formula of 5-5-6-5; 20-25 precloacal and femoral pore-bearing scales contiguous in males; dark postorbital stripes or striping on body; dark dorsal transverse blotches present; and a brown postsacral mark bearing anteriorly projecting arms. The discovery of this new species brings the number of Hemiphyllodactylus species in China to 15.

2.
Adv Biol (Weinh) ; 8(6): e2300584, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38488739

RESUMO

Nucleic acid aptamers, often termed "chemical antibodies," are short, single-stranded DNA or RNA molecules, which are selected by SELEX. In addition to their high specificity and affinity comparable to traditional antibodies, aptamers have numerous unique advantages such as wider identification of targets, none or low batch-to-batch variations, versatile chemical modifications, rapid mass production, and lack of immunogenicity. These characteristics make aptamers a promising recognition probe for scientific research or even clinical application. Aptamer-functionalized nanomaterials are now emerged as a promising drug delivery system for various diseases with decreased side-effects and improved efficacy. In this review, the technological strategies for generating high-affinity and biostable aptamers are introduced. Moreover, the development of aptamers for their application in biomedicine including aptamer-based biosensors, aptamer-drug conjugates and aptamer functionalized nanomaterials is comprehensively summarized.


Assuntos
Aptâmeros de Nucleotídeos , Técnica de Seleção de Aptâmeros , Aptâmeros de Nucleotídeos/uso terapêutico , Humanos , Técnica de Seleção de Aptâmeros/métodos , Técnicas Biossensoriais/métodos , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Animais
3.
J Hepatocell Carcinoma ; 10: 2173-2185, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38084209

RESUMO

Background: MicroRNA-612 (miR-612) has been proven to suppress the formation of invadopodia and inhibit hepatocellular carcinoma (HCC) metastasis by hydroxyacyl-CoA dehydrogenase alpha subunit (HADHA)-mediated lipid reprogramming. However, its biological roles in HCC cell ferroptosis remain unclear. Methods and Results: In this study, we found that HCC cells with high metastatic potential were more resistant to ferroptosis, indicating that ferroptosis is related to HCC metastasis. The levels of lipid reactive oxygen species (ROS) were found to be much lower in HCC cells with high metastatic potential by flow cytometry (FCM). We used HCC cells with miR-612 overexpression/knockout and HADHA overexpression/knockdown to test cell viability after stimulation with RSL3. HCC cells overexpressing miR-612 were more sensitive to ferroptosis, and miR-612 could increase lipid ROS levels. Furthermore, colony formation assays and Transwell assays showed that miR-612 could inhibit the proliferation and metastasis of HCC cells by promoting ferroptosis. We next confirmed that miR-612 influenced HCC cell ferroptosis by regulating HADHA. HADHA could upregulate the expression of key enzymes in the mevalonate (MVA) pathway. HADHA overexpression upregulated the expression of CoQ10 and decreased polyunsaturated fatty acid (PUFA) levels and lipid peroxide abundance. miR-612 also suppressed HCC cell proliferation and metastasis by enhancing RSL3- and lovastatin-induced ferroptosis in vivo. Conclusion: Overall, miR-612 promotes ferroptosis in HCC cells and affects HCC proliferation and metastasis by downregulating CoQ10 and increasing cellular PUFA levels and lipid peroxides via the HADHA-mediated MVA pathway.

4.
Clin Transl Med ; 11(3): e352, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33783988

RESUMO

BACKGROUND: S-adenosylmethionine decarboxylase proenzyme (AMD1) is a key enzyme involved in the synthesis of spermine (SPM) and spermidine (SPD), which are associated with multifarious cellular processes. It is also found to be an oncogene in multiple cancers and a potential target for tumor therapy. Nevertheless, the role AMD1 plays in hepatocellular carcinoma (HCC) is still unknown. METHODS: HCC samples were applied to detect AMD1 expression and evaluate its associations with clinicopathological features and prognosis. Subcutaneous and orthotopic tumor mouse models were constructed to analyze the proliferation and metastasis of HCC cells after AMD1 knockdown or overexpression. Drug sensitive and tumor sphere assay were performed to investigate the effect of AMD1 on HCC cells stemness. Real-time quantitative PCR (qRT-PCR), western blot, immunohistochemical (IHC) and m6A-RNA immunoprecipitation (Me-RIP) sequencing/qPCR were applied to explore the potential mechanisms of AMD1 in HCC. Furthermore, immunofluorescence, co-IP (Co-IP) assays, and mass spectrometric (MS) analyses were performed to verify the proteins interacting with AMD1. RESULTS: AMD1 was enriched in human HCC tissues and suggested a poor prognosis. High AMD1 level could promote SRY-box transcription factor 2 (SOX2), Kruppel like factor 4 (KLF4), and NANOG expression of HCC cells through obesity-associated protein (FTO)-mediated mRNA demethylation. Mechanistically, high AMD1 expression increased the levels of SPD in HCC cells, which could modify the scaffold protein, Ras GTPase-activating-like protein 1 (IQGAP1) and enhance the interaction between IQGAP1 and FTO. This interaction could enhance the phosphorylation and decrease the ubiquitination of FTO. CONCLUSIONS: AMD1 could stabilize the interaction of IQGAP1 with FTO, which then promotes FTO expression and increases HCC stemness. AMD1 shows prospects as a prognostic predictor and a therapeutic target for HCC.


Assuntos
Adenosilmetionina Descarboxilase/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Carcinoma Hepatocelular/genética , Desmetilação , Neoplasias Hepáticas/genética , RNA Mensageiro/metabolismo , Adenosilmetionina Descarboxilase/metabolismo , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Animais , Carcinoma Hepatocelular/metabolismo , Proliferação de Células/genética , Modelos Animais de Doenças , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , RNA Mensageiro/genética , Células-Tronco/metabolismo , Regulação para Cima/genética
5.
Cell Signal ; 72: 109650, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32320856

RESUMO

Epithelial-mesenchymal transition (EMT), a pivotal event during cancer progression such as relapse and metastasis, is positively correlated with the stemness potency of tumor cells. Our previous study showed that miR-296-5p attenuated EMT program of hepatocellular carcinoma cells (HCC) through NRG1/ERBB2/ERBB3 signaling. In the present study, we uncovered that miR-296-5p was able to inhibit the stemness potency of HCC by decreasing the number and size of tumorspheres, downregulating the expression of CSC biomarkers and hampering the ability of tumorigenesis in NOD/SCID mice. Brahma-related gene-1 (Brg1), as the target protein of miR-296-5p detected by bioinformatics methods, activates a series of downstream cascades through directly binding to Sall4 promoter and enhancing Sall4 transcription. Importantly, the higher expressions of Brg1 and Sall4 in tumor tissues of HCC patients suggest poorer prognoses after surgical extraction. In conclusion, miR-296-5p exerts an inhibitory effect on stemness potency of HCC cells via Brg1/Sall4 axis.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , DNA Helicases/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , Células-Tronco Neoplásicas/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Linhagem Celular Tumoral , Regulação para Baixo/genética , Molécula de Adesão da Célula Epitelial/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Endogâmicos NOD , Camundongos SCID , MicroRNAs/genética , Células-Tronco Neoplásicas/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Antígenos Thy-1/metabolismo
6.
J Exp Clin Cancer Res ; 37(1): 294, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30486894

RESUMO

BACKGROUND: Accumulation of evidence indicates that miRNAs have crucial roles in the regulation of EMT-associated properties, such as proliferation, migration and invasion. However, the underlying molecular mechanisms are not entirely illustrated. Here, we investigated the role of miR-296-5p in hepatocellular carcinoma (HCC) progression. METHODS: In vitro cell morphology, proliferation, migration and invasion were compared between HCC cell lines with up- or down-regulation of miR-296-5p. Immunofluorescence and Western blot immunofluorescence assays were used to detect the expression of EMT markers. Bioinformatics programs, luciferase reporter assay and rescue experiments were used to validate the downstream targets of miR-296-5p. Xenograft nude mouse models were established to observe tumor growth and metastasis. Immunohistochemical assays were conducted to study the relationships between miR-296-5p expression and Neuregulin-1 (NRG1)/EMT markers in human HCC samples and mice. RESULTS: miR-296-5p was prominently downregulated in HCC tissues relative to adjacent normal liver tissues and associated with favorable prognosis. Overexpression of miR-296-5p inhibited EMT along with migration and invasion of HCC cells via suppressing NRG1/ERBB2/ERBB3/RAS/MAPK/Fra-2 signaling in vitro. More importantly, miR-296-5p disrupted intrahepatic and pulmonary metastasis in vivo. NRG1, as a direct target of miR-296-5p, mediates downstream biological responses. In HCC tissues from patients and mice, the levels of miR-296-5p and NRG1 also showed an inverse relationship. CONCLUSIONS: miR-296-5p inhibited EMT-related metastasis of HCC through NRG1/ERBB2/ERBB3/RAS/MAPK/Fra-2 signaling.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Neuregulina-1/metabolismo , Receptor ErbB-2/metabolismo , Receptor ErbB-3/metabolismo , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Proliferação de Células/fisiologia , Transição Epitelial-Mesenquimal , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/genética , Neuregulina-1/genética , Receptor ErbB-2/genética , Receptor ErbB-3/genética , Transdução de Sinais , Transfecção
7.
Mol Ther Nucleic Acids ; 13: 376-386, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30347351

RESUMO

Glypican-3 (GPC3), the cellular membrane proteoglycan, has been established as a tumor biomarker for early diagnosis of hepatocellular carcinoma (HCC). GPC3 is highly expressed in more than 70% HCC tissues detected by antibody-based histopathological systems. Recently, aptamers, a short single-strand DNA or RNA generated from systematic evolution of ligands by exponential enrichment (SELEX), were reported as potential alternatives in tumor-targeted imaging and diagnosis. In this study, a total of 19 GPC3-bound aptamers were successfully screened by capillary electrophoresis (CE)-SELEX technology. After truncated, AP613-1 was confirmed to specifically target GPC3 with a dissociation constant (KD) of 59.85 nM. When modified with a phosphorothioate linkage, APS613-1 targeted GPC3 with a KD of 15.48 nM and could be used as a specific probe in living Huh7 and PLC/PRF/5 imaging, GPC3-positive cell lines, but not in L02 or A549, two GPC3-negative cell lines. More importantly, Alexa Fluor 750-conjugated APS613-1 could be used as a fluorescent probe to subcutaneous HCC imaging in xenograft nude mice. Our results indicated that modified AP613-1, especially APS613-1, was a potential agent in GPC3-positive tumor imaging for HCC early diagnosis.

8.
Int J Nanomedicine ; 13: 4433-4443, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30122918

RESUMO

PURPOSE: To construct and test a hepatocellular carcinoma (HCC)-targeted magnetic resonance probe based on a glypican-3 (GPC3)-specific aptamer (AP613-1) with ultrasmall superpara-magnetic iron oxide (USPIO). METHODS: Oleic acid-coated USPIO nanoparticles were modified with amino polyethylene glycol on the surface. Amino groups of the USPIO nanoparticles were reacted with the carboxyl group of 5' carboxyl-modified AP613-1, forming an aptamer-mediated USPIO (Apt-USPIO) probe. The material characterization of this probe including transmission electron microscopy (TEM), zeta potential, dynamic laser scattering, and magnetic behavior was carried out. The targeting efficiency and magnetic resonance imaging (MRI) performance of Apt-USPIO were evaluated both in vitro and in vivo with USPIO alone as a control. The cytotoxicity and bio-compatibility of Apt-USPIO and USPIO were analyzed by cell counting kit-8 tests in vitro and animal experiments in vivo. RESULTS: TEM imaging revealed that the Apt-USPIO nanoparticles were spherical in shape and well dispersed. Specific uptake of Apt-USPIO in Huh-7 cells could be observed using the Prussian blue staining test; however, no uptake of USPIO could be found. In vitro phantom T2-weighted MRI showed a significant decrease of the signal intensity in Apt-USPIO-incubated Huh-7 cells compared to USPIO-incubated Huh-7 cells. In vivo T2-weighted MRI showed significantly negative enhancement in the Huh-7 tumors enhanced with Apt-USPIO, whereas no enhancement was found with USPIO alone. Excellent biocompatibility of Apt-USPIO and USPIO was also demonstrated. CONCLUSION: In this study, a molecular MRI probe which was highly specific to GPC3 on HCC was successfully prepared. Our results validated the targeted imaging effect of this Apt-USPIO probe in vivo for GPC3-expressing HCCs in xenograft mice.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Glipicanas/metabolismo , Neoplasias Hepáticas/diagnóstico , Espectroscopia de Ressonância Magnética , Sondas Moleculares/química , Animais , Materiais Biocompatíveis/farmacologia , Carcinoma Hepatocelular/patologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Endocitose/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/toxicidade , Nanopartículas de Magnetita/ultraestrutura , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Tamanho da Partícula , Imagens de Fantasmas , Reprodutibilidade dos Testes , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Cogn Behav Pract ; 20(2): 202-212, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23667305

RESUMO

China is considered to be the new frontier of the global AIDS pandemic. Although effective treatment for HIV is becoming widely available in China, adherence to treatment remains a challenge. This study aimed to adapt an intervention promoting HIV-medication adherence-favorably evaluated in the West-for Chinese HIV-positive patients. The adaptation process was theory-driven and covered several key issues of cultural adaptation. We considered the importance of interpersonal relationships and family in China and cultural notions of health. Using an evidence-based treatment protocol originally designed for Western HIV-positive patients, we developed an 11-step Chinese Life-Steps program with an additional culture-specific intervention option. We describe in detail how the cultural elements were incorporated into the intervention and put into practice at each stage. Clinical considerations are also outlined and followed by two case examples that are provided to illustrate our application of the intervention. Finally, we discuss practical and research issues and limitations emerging from our field experiments in a HIV clinic in Beijing. The intervention was tailored to address both universal and culturally specific barriers to adherence and is readily applicable to generalized clinical settings. This evidence-based intervention provides a case example of the process of adapting behavioral interventions to culturally diverse communities with limited resources.

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