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1.
Nanoscale ; 16(18): 8907-8914, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38625084

RESUMO

On-chip polarization-sensitive photodetectors are highly desired for ultra-compact optoelectronic systems. It has been demonstrated that polarization-sensitive photodetection can be realized using intrinsic chiral and anisotropy materials. However, these photodetectors can only realize the detection of either circularly polarized light (CPL) or linear polarized light (LPL) and are not applicable to multiple-polarization-sensitive photodetection. Herein, we experimentally demonstrate a metasurface-integrated semiconductor to realize multiple-polarization-sensitive photodetection at visible wavelengths. This device is composed of a MoSe2 monolayer on an H-shaped plasmonic nanostructure. The geometric chirality and anisotropy of the H-shaped nanostructure result in CPL and LPL resolved optical responses. By integrating a plasmonic metasurface with monolayer MoSe2, we converted polarization-sensitive optical absorption to the polarization-sensitive photocurrent of the device through the photoconductive effect. Polarization-sensitive photocurrent responses to both CPL and LPL are systematically investigated, which demonstrate a high photocurrent circular dichroism (CD) of 0.35 at a wavelength of 810 nm and photocurrent linear polarization (LP) of 0.4 at a wavelength of 633 nm. Our results provide a potential pathway to realize multiple-polarization-sensitive applications in medicine analysis, biology, and remote sensing.

2.
Adv Sci (Weinh) ; 11(20): e2306344, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38489745

RESUMO

In recent years, numerous efforts have been devoted to exploring innovative micro/nano-optical devices (MNODs) with reconfigurable functionality, which is highly significant because of the progressively increasing requirements for next-generation photonic systems. Fortunately, phase change materials (PCMs) provide an extremely competitive pathway to achieve this goal. The phase transitions induce significant changes to materials in optical, electrical properties or shapes, triggering great research interests in applying PCMs to reconfigurable micro/nano-optical devices (RMNODs). More specifically, the PCMs-based RMNODs can interact with incident light in on-demand or adaptive manners and thus realize unique functions. In this review, RMNODs based on phase transitions are systematically summarized and comprehensively overviewed from materials, phase change mechanisms to applications. The reconfigurable optical devices consisting of three kinds of typical PCMs are emphatically introduced, including chalcogenides, transition metal oxides, and shape memory alloys, highlighting the reversible state switch and dramatic contrast of optical responses along with designated utilities generated by phase transition. Finally, a comprehensive summary of the whole content is given, discussing the challenge and outlooking the potential development of the PCMs-based RMNODs in the future.

3.
Circ Res ; 134(7): e17-e33, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38420756

RESUMO

BACKGROUND: Microvascular complications are the major outcome of type 2 diabetes progression, and the underlying mechanism remains to be determined. METHODS: High-throughput RNA sequencing was performed using human monocyte samples from controls and diabetes. The transgenic mice expressing human CTSD (cathepsin D) in the monocytes was constructed using CD68 promoter. In vivo 2-photon imaging, behavioral tests, immunofluorescence, transmission electron microscopy, Western blot analysis, vascular leakage assay, and single-cell RNA sequencing were performed to clarify the phenotype and elucidate the molecular mechanism. RESULTS: Monocytes expressed high-level CTSD in patients with type 2 diabetes. The transgenic mice expressing human CTSD in the monocytes showed increased brain microvascular permeability resembling the diabetic microvascular phenotype, accompanied by cognitive deficit. Mechanistically, the monocytes release nonenzymatic pro-CTSD to upregulate caveolin expression in brain endothelium triggering caveolae-mediated transcytosis, without affecting the paracellular route of brain microvasculature. The circulating pro-CTSD activated the caveolae-mediated transcytosis in brain endothelial cells via its binding with low-density LRP1 (lipoprotein receptor-related protein 1). Importantly, genetic ablation of CTSD in the monocytes exhibited a protective effect against the diabetes-enhanced brain microvascular transcytosis and the diabetes-induced cognitive impairment. CONCLUSIONS: These findings uncover the novel role of circulatory pro-CTSD from monocytes in the pathogenesis of cerebral microvascular lesions in diabetes. The circulatory pro-CTSD is a potential target for the intervention of microvascular complications in diabetes.


Assuntos
Catepsina D , Diabetes Mellitus Tipo 2 , Monócitos , Animais , Humanos , Camundongos , Encéfalo/metabolismo , Catepsina D/metabolismo , Catepsina D/farmacologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Precursores Enzimáticos , Camundongos Transgênicos , Monócitos/metabolismo , Transcitose/fisiologia
4.
Metabolism ; 152: 155761, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38104924

RESUMO

BACKGROUND: Mitochondrial dysfunction and metabolic reprogramming are key features of hepatocellular carcinoma (HCC). Despite its significance, the precise underlying mechanism behind these processes has not been fully elucidated. The latest investigations, along with our previous discoveries, have substantiated the significant role of mitochondrial ribosomal protein L12 (MRPL12), a newly identified gene involved in mitochondrial transcription regulation, in the modulation of mitochondrial metabolism. Nevertheless, the role of MRPL12 in tumorigenesis has yet to be investigated. METHODS: The expression of MRPL12 in HCC was assessed using an online database. Western blot, quantitative real-time polymerase chain reaction (qRT-PCR), and immunohistochemistry (IHC) were employed to determine the expression of MRPL12 in HCC tissues, patient-derived organoid (PDO), and cell lines. The correlation between MRPL12 expression and clinicopathological features, as well as prognosis, was examined using tissue microarray analysis. An in vivo subcutaneous tumor xenograft model, gene knockdown or overexpression assay, chromatin immunoprecipitation (ChIP) assay, Seahorse XF96 assay, and cell function assay were employed to investigate the biological function and potential molecular mechanism of MRPL12 in HCC. RESULTS: A significant upregulation of MRPL12 was observed in HCC cells, PDO and patient tissues, which correlated with advanced tumor stage, higher grade and poor prognosis. MRPL12 overexpression promoted cell proliferation, migration, and invasion in vitro, as well as tumorigenicity in vivo, whereas MRPL12 knockdown showed the opposite effect. MRPL12 knockdown also inhibited the capacity of organoids proliferation capacity. Furthermore, MRPL12 was found to be crucial for maintaining mitochondrial homeostasis. Both gain and loss-of-function experiments targeting MRPL12 in HCC cells altered oxidative phosphorylation (OXPHOS) and mitochondrial DNA content. Notably, suppression of OXPHOS effectively mitigates the tumor-promoting effect attributed to MRPL12 overexpression, implying the involvement of MRPL12 in HCC through the modulation of mitochondrial metabolism. Besides, Yin Yang 1 (YY1) was identified as a transcription factor responsible for regulating MRPL12, while the PI3K/mTOR pathway was found to act as an upstream regulator of YY1. MRPL12 knockdown attenuated the YY1 overexpression or PI3K/mTOR activation-induced malignant phenotype in HCC cells. CONCLUSION: Our findings provide compelling evidence that MRPL12 is implicated in driving the malignant phenotype of HCC via regulating mitochondrial metabolism. Moreover, the aberrant expression of MRPL12 in HCC is mediated by the upstream PI3K/mTOR/YY1 pathway. These results highlight the potential of targeting MRPL12 as a promising therapeutic strategy for the treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteínas Ribossômicas , Humanos , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/metabolismo , Reprogramação Metabólica , Biogênese de Organelas , Fosfatidilinositol 3-Quinases/metabolismo , Serina-Treonina Quinases TOR/metabolismo
5.
Exp Mol Pathol ; 134: 104871, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37696326

RESUMO

Homeobox (HOX) genes encode highly conserved transcription factors that play vital roles in embryonic development. DNA methylation is a pivotal regulatory epigenetic signaling mark responsible for regulating gene expression. Abnormal DNA methylation is largely associated with the aberrant expression of HOX genes, which is implicated in a broad range of human diseases, including cancer. Numerous studies have clarified the mechanisms of DNA methylation in both physiological and pathological processes. In this review, we focus on how DNA methylation regulates HOX genes and briefly discuss drug development approaches targeting these mechanisms.


Assuntos
Genes Homeobox , Neoplasias , Humanos , Genes Homeobox/genética , Metilação de DNA/genética , Neoplasias/genética , Fatores de Transcrição/genética , Desenvolvimento Embrionário/genética
6.
Nanomaterials (Basel) ; 13(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37764546

RESUMO

For developing high-performance organic light-emitting diodes (OLEDs) with thermally activated delayed fluorescent (TADF) emitters, the diphenyltriazine (TRZ) unit was introduced onto the 2'- and 3'-positions of xanthene moiety of spiro[fluorene-9,9'-xanthene] (SFX) to construct n-type host molecules, namely 2'-TRZSFX and 3'-TRZSFX. The outward extension of the TRZ unit, induced by the meta-linkage, resulted in a higher planarity between the TRZ unit and xanthene moiety in the corresponding 3'-TRZSFX. Additionally, this extension led to a perched T1 level, as well as a lower unoccupied molecular orbital (LUMO) level when compared with 2'-TRZSFX. Meanwhile, the 3'-TRZSFX molecules in the crystalline state presented coherent packing along with the interaction between TRZ units; the similar packing motif was spaced apart from xanthene moieties in the 2'-TRZSFX crystal. These endowed 3'-TRZSFX superior electron transport capacity in single-carrier devices relative to the 2'-TRZSFX-based device. Hence, the 3'-TRZSFX-based TADF-OLED showed remarkable electroluminescent (EL) performance under the operating luminance from turn-on to ca. 1000 cd·m-2 with a maximum external quantum efficiency (EQEmax) of 23.0%, thanks to its matched LUMO level with 4CzIPN emitter and better electron transport capacity. Interestingly, the 2'-TRZSFX-based device, with an EQEmax of 18.8%, possessed relatively low roll-off and higher efficiency when the operating luminance exceeded 1000 cd·m-2, which was attributed to the more balanced carrier transport under high operating voltage. These results were elucidated by the analysis of single-crystal structures and the measurements of single-carrier devices, combined with EL performance. The revealed position effect of the TRZ unit on xanthene moiety provides a more informed strategy to develop SFX-based hosts for highly efficient TADF-OLEDs.

7.
Micromachines (Basel) ; 13(6)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35744470

RESUMO

Three-dimensional (3D) nanostructures have attracted widespread attention in physics, chemistry, engineering sciences, and biology devices due to excellent functionalities which planar nanostructures cannot achieve. However, the fabrication of 3D nanostructures is still challenging at present. Reliable fabrication, improved controllability, and multifunction integration are desired for further applications in commercial devices. In this review, a powerful fabrication method to realize 3D nanostructures is introduced and reviewed thoroughly, which is based on atomic layer deposition assisted 3D assembly through various sacrificial templates. The aim of this review is to provide a comprehensive overview of 3D nanofabrication based on atomic layer assembly (ALA) in multifarious sacrificial templates for 3D nanostructures and to present recent advancements, with the ultimate aim to further unlock more potential of this method for nanodevice applications.

8.
J Transl Med ; 20(1): 115, 2022 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-35255935

RESUMO

BACKGROUND: Gastric cancer (GC) is one of the most common malignancies, and an increasing number of studies have shown that its pathogenesis is regulated by various miRNAs. In this study, we investigated the role of miR-875-5p in GC. METHODS: The expression of miR-875-5p was detected in human GC specimens and cell lines by miRNA qRT-PCR. The effect of miR-875-5p on GC proliferation was determined by Cell Counting Kit-8 (CCK-8) proliferation and 5-ethynyl-2'-deoxyuridine (EdU) assays. Migration and invasion were examined by transwell migration and invasion assays as well as wound healing assays. The interaction between miR-875-5p and its target gene upstream stimulatory factor 2(USF2) was verified by dual luciferase reporter assays. The effects of miR-875-5p in vivo were studied in xenograft nude mouse models. Related proteins were detected by western blot. RESULTS: The results showed that miR-875-5p inhibited the proliferation, migration and invasion of GC cells in vitro and inhibited tumorigenesis in vivo. USF2 was proved to be a direct target of miR-875-5p. Knockdown of USF2 partially counteracted the effects of miR-875-5p inhibitor. Overexpression of miR-875-5p could inhibit proliferation, migration and invasion and suppress the TGF-ß signalling pathway by downregulating USF2. CONCLUSIONS: MiR-875-5p can inhibit the progression of GC by directly targeting USF2. And in the future, miR-875-5p is expected to be a potential target for GC diagnosis and treatment.


Assuntos
MicroRNAs , Neoplasias Gástricas , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Gástricas/patologia , Fator de Crescimento Transformador beta/metabolismo , Fatores Estimuladores Upstream/genética , Fatores Estimuladores Upstream/metabolismo
9.
Biosci Trends ; 15(5): 283-298, 2021 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-34421064

RESUMO

Traditional Chinese medicine (TCM), especially Chinese herbal medicines and acupuncture, has been traditionally used to treat patients with cancers in China and other East Asian countries. Numerous studies have indicated that TCM not only alleviates the symptoms (e.g., fatigue, chronic pain, anorexia/cachexia, and insomnia) of patients with cancer and improves their quality of life (QOL) but also diminishes adverse reactions and complications caused by chemotherapy, radiotherapy, or targeted-therapy. Therefore, Chinese herbal medicines and acupuncture and other alternative therapies need to be understood by TCM physicians and other health care providers. This review mainly summarizes the experimental results and conclusions from literature published since 2010, and a search of the literature as been performed in the PubMed, MEDLINE, Web of Science, Scopus, Springer, ScienceDirect, and China Hospital Knowledge Database (CHKD) databases. Some Chinese herbal medicines (e.g., Panax ginseng, Panax quinquefolius, Astragali radix, Bu-zhong-yi-qi-tang (TJ-41), Liu-jun-zi-tang (TJ-43), Shi-quan-da-bu-tang (TJ-48), and Ban-xia-xie-xin-tang (TJ-14)) and some acupuncture points (e.g., Zusanli (ST36), Zhongwan (CV12), Neiguan (PC6) and Baihui (GV20)) that are commonly used to treat cancer-related symptoms and/or to reduce the toxicity of chemotherapy, radiotherapy, or targeted-therapy are highlighted and summarized. Through a review of literature, we conclude that TCM can effectively alleviate adverse gastrointestinal reactions (including diarrhea, nausea, and vomiting) to these anti-cancer therapies, decrease the incidence of bone marrow suppression, alleviate cardiotoxicity, and protect against chemotherapy-induced peripheral neuropathy and radiation-induced pneumonitis. Moreover, TCM can alleviate epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI)-related acneiform eruptions, diarrhea, and other adverse reactions. The hope is that this review can contribute to an understanding of TCM as an adjuvant therapy for cancer and that it can provide useful information for the development of more effective anti-cancer therapies. However, more rigorously designed trials involving cancer treatment must be conducted in the future, including complete quality control and standardized models at the cellular, organic, animal and clinical levels, in order to study TCM in multiple forms and at multiple levels.


Assuntos
Medicamentos de Ervas Chinesas , Neoplasias , Animais , Terapia Combinada , Bases de Dados Factuais , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Medicina Tradicional Chinesa , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Qualidade de Vida
10.
Front Cell Dev Biol ; 9: 700195, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34434929

RESUMO

Mitochondrial injury of tubular epithelial cells (TECs) is the key pathogenic event underlying various kidney diseases and a potential intervening target as well. Our previous study demonstrated that ING2 is ubiquitously expressed at tubulointerstitial area within kidneys, while its role in regulating TEC mitochondrial respiration is not fully elucidated. To clarify the roles of ING2 in mitochondrial homeostasis of TECs and pathogenesis of acute ischemic kidney injury, Western blot, PCR, immunofluorescence, immunoprecipitation, and oxygen consumption rate assay were applied to address the roles of ING2 in modulating mitochondrial respiration. We further complemented these studies with acute ischemic kidney injury both in vitro and in vivo. In vitro study demonstrated ING2 could positively control TEC mitochondrial respiration. Concurrently, both mRNA and protein levels of mtDNA encoded respiratory chain components were altered by ING2, suggesting ING2 could regulate mtDNA transcription. In mechanism, ING2 could regulate the ubiquitination of a newly identified mitochondrial transcription factor MRPL12, thereby modulating its cellular stability and abundance. We also demonstrated ING2-mediated modulation on mtDNA transcription and mitochondrial respiration are involved in serum deprivation induced TEC injuries. Finally, immunohistochemistry study revealed that ING2 expression was significantly altered in kidney biopsies with acute ischemic kidney injury. In vivo study suggested that kidney specific ING2 overexpression could effectively ameliorate acute ischemic kidney injury. Our study demonstrated that ING2 is a crucial modulator of TEC mitochondrial respiration. These findings suggested a unrecognized role of ING2 in TEC mitochondrial energetic homeostasis and a potential intervening target for TEC mitochondrial injury associated pathologies.

11.
Oxid Med Cell Longev ; 2021: 6691226, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33680286

RESUMO

Diabetic kidney disease (DKD) is the major cause of end-stage renal disease (ESRD). In the past few decades, there has been a large amount of evidence to highlight the pivotal role of oxidative stress in the development and progression of DKD. However, the detailed molecular mechanisms are not fully elucidated. A new sight has been established that the mitochondrial acetyltransferase GCN5L1 participates in cellular redox homeostasis maintenance in DKD. Firstly, we found that the expression of GCN5L1 is significantly elevated both in human and mouse kidney tissues with DKD and in hyperglycemic renal tubular epithelial cells (TECs), while deletion of GCN5L1 could effectively ameliorate oxidative stress-induced renal injury in DKD. Furthermore, deletion of GCN5L1 could reduce MnSOD acetylation on lysine 68 and activate its activity, thereby scavenging excessive ROS and relieving oxidative stress-induced renal inflammation and fibrosis. In general, GCN5L1-mediated acetylation of MnSOD exacerbated oxidative stress-induced renal injury, suggesting that GCN5L1 might be a potential intervention target in DKD.


Assuntos
Nefropatias Diabéticas/patologia , Proteínas Mitocondriais/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Acetilação/efeitos dos fármacos , Animais , Linhagem Celular , Nefropatias Diabéticas/complicações , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Glucose/toxicidade , Humanos , Inflamação/patologia , Túbulos Renais/patologia , Lisina/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Proteinúria/complicações , Proteinúria/patologia , Espécies Reativas de Oxigênio/metabolismo , Estreptozocina , Ubiquitinação
12.
J Recept Signal Transduct Res ; 40(3): 257-263, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32098557

RESUMO

Fibroblast growth factor receptor-like-1 (FGFRL1) is important to cell motility and links with tumorigenic potential in various types of cancers. To investigate the biological function and underlying mechanism of FGFRL1 in rectal adenocarcinoma, we conducted this study. TCGA and Oncomine databases were used to analyze FGFRL1 expression and its association with clinical characteristics or overall survival (OS) in rectal adenocarcinoma patients. siRNA strategy was implemented to knockdown FGFRL1 expression in rectal adenocarcinoma cells. CCK8, colony formation, wound healing, and transwell assays were implemented to measure cell behaviors. qRT-PCR and western blot were utilized to identify mRNA and protein expression levels. FGFRL1 was significantly increased in rectal adenocarcinoma tissue samples, either colon or rectum. High-regulation of FGFRL1 expression induced poorer outcome of rectal adenocarcinoma patients. Downregulation of FGFRL1 inhibited the proliferation, colony formation, migration, and invasion of SW837 cells. The MAPK pathway-related proteins, phosphorylation of MEK and ERK, were also decreased after si-FGFRL1 transfection. These findings demonstrated that FGFRL1, acting as a potential inducator, may promote the progression of rectal adenocarcinoma via activating the MAPK signaling pathway.


Assuntos
Adenocarcinoma/tratamento farmacológico , Terapia de Alvo Molecular , Receptor Tipo 5 de Fator de Crescimento de Fibroblastos/metabolismo , Neoplasias Retais/tratamento farmacológico , Adenocarcinoma/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Receptor Tipo 5 de Fator de Crescimento de Fibroblastos/genética , Neoplasias Retais/patologia , Ensaio Tumoral de Célula-Tronco
13.
J Cancer Res Ther ; 15(2): 437-441, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30964123

RESUMO

OBJECTIVE: The objective of the study was to evaluate the usefulness of large-section cytokeratin 20 (CK20) staining technique in the detection of infiltration on the distal wall and mesangial metastasis in patients with middle and lower rectal cancer. MATERIALS AND METHODS: A total of 62 patients with rectal cancer in the middle and lower segment were studied on large slices stained with CK20. Logistic regression was used to analyze the clinicopathologic factors related to distal low and middle rectal cancer metastasis to the mesorectum and rectal wall. RESULTS: Two types of distal metastasis of the tumor were observed in the rectal wall in 18% (11/62) of the patients: submucosal invasion and muscularis propria invasion. The extent of distal metastasis to the rectal wall was around 0.5-1.0 cm. Four types of distal metastasis occurred in the mesorectum: lymph node invasion, blood and lymphatic vessel invasion, perineural invasion, and isolated neoplastic microfoci. Distal metastasis to the mesorectum was observed in 24% (15/62) of the patients. The extent of metastasis to the mesorectum was around 0.5-4.0 cm. Another three patients with microcapillary invasion in the distal mesorectum were observed by immunohistochemistry, as it was difficult to determine the spread by conventional hematoxylin and eosin staining. CONCLUSION: The large-section CK20 staining technique is useful for the detection of infiltration on the distal wall and mesangial metastasis in patients with middle and lower rectal cancer.


Assuntos
Queratina-20/metabolismo , Neoplasias Retais/metabolismo , Neoplasias Retais/patologia , Reto/metabolismo , Reto/patologia , Biomarcadores , Seguimentos , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metástase Linfática , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Neoplasias Retais/mortalidade
14.
J Pharm Biomed Anal ; 166: 105-112, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30640042

RESUMO

USP's peptide reference standards content is typically determined using an HPLC assay against an external standard for which the purity was determined by a mass balance approach. To explore the use of other analytical methods, the USP Biologics Department conducted a multi-laboratory collaborative study. The study determined the inter-laboratory variability for peptide quantitation using the following methods: HPLC assay, quantitative nuclear magnetic resonance (qNMR) spectroscopy, or amino acid analysis (AAA). The three methods were compared with regard to their suitability for quantitation of the nonapeptide oxytocin. In this study, the HPLC assay method using the same peptide bulk material as the standard showed the lowest inter-lab variability. The coefficient of variation (%CV) was calculated without counting the uncertainty associated with the purity assignment of the standard with mass balance. The proton qNMR method is a direct measurement of the peptide against an internal standard, which is not difficult to perform under common laboratory conditions. Because of the simpler operation and shorter analytical time, qNMR as a primary method for peptide reference standard value assignment deserves further exploration.


Assuntos
Técnicas de Química Analítica/métodos , Ocitocina/análise , Aminoácidos/análise , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Padrões de Referência , Reprodutibilidade dos Testes
15.
Oncol Lett ; 15(5): 7707-7715, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29740490

RESUMO

Colorectal cancer (CRC) is the third most common cause of cancer-associated mortality worldwide. Currently, 5-fluorouracil (5-FU) remains a widely used chemotherapeutic drug in the treatment of CRC; however, 5-FU resistance during treatment has become a common problem. Livin, a member of the inhibitor of apoptosis protein family, is considered to be associated with tumor resistance to chemotherapy. In the present study, Livin-silenced cells were generated by introducing a lentivirus into HCT116 and SW620 colon cancer cell lines. Acridine orange/ethidium bromide staining was used as an indicator of cell death. Western blot analysis was performed to detect protein expression levels, and transmission electron microscopy was used to assess autophagy. The half-maximal inhibitory concentration of 5-FU in colon cancer cells was evaluated using a Cell Counting Kit-8 assay. The results of the present study confirmed that silencing Livin significantly enhanced colon cancer cell death in the presence of 5-FU, increased expression levels of various apoptosis- and autophagy-associated proteins and augmented chemotherapeutic sensitivity to 5-FU. Furthermore, the present study demonstrated that this effect may be reversed when autophagy or apoptosis was inhibited, indicating that apoptosis and autophagy were involved in this process. The protein kinase B signaling pathway and B-cell lymphoma-2 expression levels significantly decreased following Livin knockdown, suggesting they may contribute to the regulation of apoptosis and autophagy crosstalk, which caused the Livin knockdown-induced cell death observed.

16.
Oncol Lett ; 14(6): 7759-7766, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29344221

RESUMO

Livin is a novel member of the inhibitor of apoptosis protein family, which has been identified to be expressed in various malignancies and is suggested to be associated with poor prognostic significance. However, no data are available concerning the significance of livin in mid-distal rectal cancer. In the present study, livin expression, and its association with clinicopathological characteristics and prognosis was examined in patients with mid-distal rectal cancer. Apoptotic susceptibility, invasion capacity and chemosensitivity of LoVo cells were investigated using small interfering RNA (siRNA)-mediated knockdown of livin. It was revealed that livin was highly expressed in mid-distal rectal cancer tissues compared with the normal rectal mucosal tissues. Livin expression was associated with pathological grade, extent of invasion (T stage) and extent of lymph node metastasis (N stage) of tumor, contributing to poor prognosis of mid-distal rectal cancer following surgery. The data suggest that aggressive surgery should be applied in patients with mid-distal rectal cancer with high expression of livin. It was also revealed that knockdown of livin by siRNA increased the apoptotic rate, suppressed invasion of LoVo cells, and decreased the half-maximal inhibitory concentration of oxaliplatin and 5-fluorouracil by ~50% in LoVo cells significantly compared with control groups. The data suggested that a combination of downregulation of livin and anticancer drugs may significantly decrease the toxicity of anticancer drugs. Taken together, the present study indicated that livin may be a promising target in clinical therapy of mid-distal rectal cancer.

17.
Tumour Biol ; 37(11): 15133-15143, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27677286

RESUMO

Renal cell carcinoma (RCC) accounts for 3 % of all adult malignancies and is the most lethal urological cancer. Livin is a member of the inhibitor of apoptosis protein (IAP) family, which is associated with tumor resistance to radiotherapy and chemotherapy. Clinical data also showed that patients with high tumor grades and stages have higher expression levels of Livin in RCC cells. Autophagy is a survival mechanism activated in response to nutrient deprivation. A possible role of Livin in the autophagy of RCC cells has not been investigated; therefore, this pioneer study was carried out. Livin was silenced in RCC cells (slow virus infection [SVI]-shLivin cells) by lentiviral transfection. Then, mRNA and protein expression levels in the transfected cells were assessed by quantitative fluorescence PCR and Western blotting, respectively. In addition, acridine orange staining and electron microscopy were used to assess autophagy in SVI-shLivin cells. The cisplatin IC50 values for RCC cells were measured by the CCK8 assay. Potent antitumor activities were observed in xenograft mouse models generated with Livin-silenced RCC cells in terms of delayed tumor onset and suppressed tumor growth. These results suggested that Livin silencing could increase the chemotherapeutic sensitivity of RCC cells to cisplatin and induce autophagic cell death. A possible mechanism of Bcl-2 and Akt pathway involvement was discussed specifically in this study. Overall, Livin silencing induces apoptotic and autophagic cell death and increases chemotherapeutic sensitivity of RCC cells to cisplatin.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carcinoma de Células Renais/patologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas Inibidoras de Apoptose/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Antineoplásicos/farmacologia , Biomarcadores Tumorais , Western Blotting , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/metabolismo , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Técnicas Imunoenzimáticas , Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Proteínas Inibidoras de Apoptose/genética , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Gradação de Tumores , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Tumour Biol ; 37(9): 12731-12742, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27448305

RESUMO

Although GC (gemcitabine and cisplatin) chemotherapy remains an effective method for treating bladder cancer (BCa), chemoresistance is a major obstacle in chemotherapy. In this study, we determined whether gemcitabine resistance correlates with migratory/invasive potential in BCa and whether this relationship is regulated by the cylindromatosis (CYLD)-Livin module. First, we independently investigated the correlation of CYLD/Livin and gemcitabine resistance with the potential for tumor migration and invasiveness. Second, we found that co-transfected CYLD and Livin dramatically improved sensitivity to gemcitabine chemotherapy and decreased migration/invasion potential. Next, we determined that CYLD may regulate Livin by the NF-κB-dependent pathway. We also found that CYLD overexpression and Livin knockdown might improve gemcitabine chemosensitivity by decreasing autophagy and increasing apoptosis in BCa cells. Finally, the effects of CYLD-Livin on tumor growth in vivo were evaluated. Our study demonstrates that CYLD-Livin might represent a potential therapeutic for chemoresistant BCa.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Movimento Celular/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Proteínas Inibidoras de Apoptose/genética , Proteínas de Neoplasias/genética , Proteínas Supressoras de Tumor/genética , Neoplasias da Bexiga Urinária/tratamento farmacológico , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Antimetabólitos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Autofagia/efeitos dos fármacos , Autofagia/genética , Western Blotting , Linhagem Celular Tumoral , Movimento Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Desoxicitidina/farmacologia , Enzima Desubiquitinante CYLD , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Proteínas de Neoplasias/metabolismo , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Supressoras de Tumor/metabolismo , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
19.
Biomarkers ; 19(1): 81-5, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24410190

RESUMO

The purpose of the study was to explore the significance of FGFR4 protein expression in colorectal cancer. Immunohistochemistry showed 46.8% (148/316) tumors positive for FGFR4 and 7.3% (23/316) for adjacent normal specimens. FGFR4 positivity was correlated with shortened disease free survival (DFS) and overall survival (OS). Multivariate analysis revealed that FGFR4 was an independent prognostic factor. FGFR4 silencing markedly reduced the migration and invasion capacity of colorectal cancer cell lines. These results suggest FGFR4 is a potential prognostic and therapeutic marker for colorectal cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/metabolismo , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/metabolismo , Idoso , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Movimento Celular , Neoplasias Colorretais/mortalidade , Feminino , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética
20.
BMC Cancer ; 14: 28, 2014 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-24433541

RESUMO

BACKGROUND: Distal esophageal adenocarcinoma is a highly aggressive neoplasm. Despite advances in diagnosis and therapy, the prognosis is still poor. Stathmin (STMN-1) is a ubiquitously expressed microtubule destabilizing phosphoprotein. It promotes the disassembly of microtubules and prevents assembly. STMN-1 can cause uncontrolled cell proliferation when mutated and not functioning properly. Recently, found to be overexpressed in many types of human cancers. However, its clinical significance remains elusive in distal esophageal adenocarcinoma. Here, we reported for the first time that STMN-1 is highly overexpressed in adenocarcinomas of the distal esophagus and strongly associated with lymph node metastasis. METHODS: STMN-1 expression in 63 cases of distal esophageal adenocarcinoma was analyzed by immunoblotting, while expression in esophageal adenocarcinoma cells was determined by immunocytochemistry, immunofluorescence, qRT-PCR and western blotting. Lentivirus-mediated RNAi was employed to knock-down STMN-1 expression in Human esophageal adenocarcinoma cells. The relationship between STMN-1 expression and lymph node metastasis in distal esophageal adenocarcinoma was determined by univariate and multivariate analyses. RESULTS: STMN-1 was detected in 31 (49.21%) of the 63 cases. STMN-1 was highly overexpressed in specimens with lymph node metastasis pN (+), but its expression was almost undetected in pN (-) status. Multivarian regression analysis demonstrated that STMN-1 overexpression is an independent factor for lymph node metastasis in distal esophageal adenocarcinoma. STMN-1 shRNA effectively reduced STMN-1 expression in esophageal adenocarcinoma cells (P < 0.05), which significantly suppressed proliferation (P < 0.05), increased migration (P < 0.05) and invasion ability (P < 0.05) and G1 phase arrest (P < 0.05) which lead to induction of apoptosis in esophageal adenocarcinoma cells in vitro. To verify the in vitro data, we conducted in vivo tumor xenograft studies. Esophageal adenocarcinoma cells stably transfected with STMN-1 shRNA significantly reduced tumor xenografts volume in vivo. CONCLUSIONS: STMN-1 overexpression is associated with lymph node metastasis and increase malignancy in distal esophageal adenocarcinoma. In vivo and in vitro laboratory findings, suggests that STMN-1 may be a suitable target for future therapeutic strategies in distal esophageal adenocarcinoma.


Assuntos
Adenocarcinoma/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Esofágicas/metabolismo , Interferência de RNA , Estatmina/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/secundário , Adenocarcinoma/terapia , Adulto , Apoptose , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/terapia , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular , Humanos , Modelos Logísticos , Metástase Linfática , Masculino , Análise Multivariada , Invasividade Neoplásica , Fenótipo , Estatmina/genética , Fatores de Tempo , Transfecção , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
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