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1.
Breast Cancer Res ; 26(1): 13, 2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238761

RESUMO

BACKGROUND: Endocrine therapy resistance in hormone receptor-positive/HER2-negative (HR+/HER2-) breast cancer (BC) is a significant clinical challenge that poses several unmet needs in the management of the disease. This study aimed to investigate the prognostic value of c-MET-positive circulating tumor cells (cMET+ CTCs), ESR1/PIK3CA mutations, and cell-free DNA (cfDNA) concentrations in patients with hormone receptor-positive (HR+) metastatic breast cancer (mBC). METHODS: Ninety-seven patients with HR+ mBC were prospectively enrolled during standard treatment at Samsung Medical Center. CTCs were isolated from blood using GenoCTC® and EpCAM or c-MET CTC isolation kits. PIK3CA and ESR1 hotspot mutations were analyzed using droplet digital PCR. CfDNA concentrations were calculated using internal control copies from the ESR1 mutation test. Immunocytochemistry was performed to compare c-MET overexpression between primary and metastatic sites. RESULTS: The proportion of c-MET overexpression was significantly higher in metastatic sites than in primary sites (p = 0.00002). Survival analysis showed that c-MET+ CTC, cfDNA concentration, and ESR1 mutations were significantly associated with poor prognosis (p = 0.0026, 0.0021, and 0.0064, respectively) in HR+/HER2- mBC. By contrast, EpCAM-positive CTC (EpCAM+ CTC) and PIK3CA mutations were not associated with progression-free survival (PFS) in HR+/HER2- mBC. Multivariate analyses revealed that c-MET+ CTCs and cfDNA concentration were independent predictors of PFS in HR+/HER2- mBC. CONCLUSIONS: Monitoring c-MET+ CTC, rather than assessing c-MET expression in the primary BC site, could provide valuable information for predicting disease progression, as c-MET expression can change during treatment. The c-MET+ CTC count and cfDNA concentration could provide complementary information on disease progression in HR+ /HER2- mBC, highlighting the importance of integrated liquid biopsy.


Assuntos
Neoplasias da Mama , Ácidos Nucleicos Livres , Células Neoplásicas Circulantes , Humanos , Feminino , Neoplasias da Mama/patologia , Células Neoplásicas Circulantes/patologia , Ácidos Nucleicos Livres/uso terapêutico , Prognóstico , Molécula de Adesão da Célula Epitelial/genética , Biomarcadores Tumorais/genética , Progressão da Doença , Classe I de Fosfatidilinositol 3-Quinases/genética , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo
2.
J Biol Chem ; 295(19): 6754-6766, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32184354

RESUMO

The atypical trichromatic cyanobacterial phytochrome NpTP1 from Nostoc punctiforme ATCC 29133 is a linear tetrapyrrole (bilin)-binding photoreceptor protein that possesses tandem-cysteine residues responsible for shifting its light-sensing maximum to the violet spectral region. Using bioinformatics and phylogenetic analyses, here we established that tandem-cysteine cyanobacterial phytochromes (TCCPs) compose a well-supported monophyletic phytochrome lineage distinct from prototypical red/far-red cyanobacterial phytochromes. To investigate the light-sensing diversity of this family, we compared the spectroscopic properties of NpTP1 (here renamed NpTCCP) with those of three phylogenetically diverged TCCPs identified in the draft genomes of Tolypothrix sp. PCC7910, Scytonema sp. PCC10023, and Gloeocapsa sp. PCC7513. Recombinant photosensory core modules of ToTCCP, ScTCCP, and GlTCCP exhibited violet-blue-absorbing dark-states consistent with dual thioether-linked phycocyanobilin (PCB) chromophores. Photoexcitation generated singly-linked photoproduct mixtures with variable ratios of yellow-orange and red-absorbing species. The photoproduct ratio was strongly influenced by pH and by mutagenesis of TCCP- and phytochrome-specific signature residues. Our experiments support the conclusion that both photoproduct species possess protonated 15E bilin chromophores, but differ in the ionization state of the noncanonical "second" cysteine sulfhydryl group. We found that the ionization state of this and other residues influences subsequent conformational change and downstream signal transmission. We also show that tandem-cysteine phytochromes present in eukaryotes possess similar amino acid substitutions within their chromophore-binding pocket, which tune their spectral properties in an analogous fashion. Taken together, our findings provide a roadmap for tailoring the wavelength specificity of plant phytochromes to optimize plant performance in diverse natural and artificial light environments.


Assuntos
Proteínas de Bactérias/química , Cianobactérias/química , Fotorreceptores Microbianos/química , Fitocromo/química , Substituição de Aminoácidos , Proteínas de Bactérias/genética , Cianobactérias/genética , Mutação de Sentido Incorreto , Fotorreceptores Microbianos/genética , Fitocromo/genética
3.
Int J Mol Sci ; 22(5)2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33670861

RESUMO

Human papillomavirus (HPV) in high-risk groups is known to suppress the type I interferon (IFN) signaling pathway leading to the transcription of interferon-stimulated genes (ISGs), which have many antiviral functions. However, the effects of HPV on the action of various ISGs in low-risk groups are not fully understood. We aimed to investigate whether antiviral ISGs are expressed in transfected keratinocytes with type 2 HPV (HPV-2) E7. The mRNA and protein expressions of ISGs and type I IFN signaling pathway components were evaluated by quantitative real-time polymerase chain reaction, western blot, immunofluorescence, and/or immunohistochemistry. Compared with normal skin, mRNA expression of all ISGs in HPV-2 positive cutaneous warts was significantly decreased (p < 0.05). In comparison with empty vector transfection, E7 transfection significantly down-regulated the mRNA and protein expressions of ISGs and type I IFN signaling pathway components, which were significantly up-regulated by E7 siRNA transfection (p < 0.05). Interestingly, epigallocatechin-3-gallate (EGCG) pretreatment up-regulated the mRNA and protein expressions of ISGs and type I IFN signaling pathway components, which were significantly down-regulated by E7 transfection (p < 0.05). Our results demonstrate that EGCG is a potential candidate for cutaneous wart prevention.


Assuntos
Catequina/análogos & derivados , Regulação da Expressão Gênica , Interferon Tipo I/metabolismo , Papillomaviridae/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/tratamento farmacológico , Antivirais/farmacologia , Antivirais/uso terapêutico , Catequina/farmacologia , Catequina/uso terapêutico , Linhagem Celular , Células HaCaT , Humanos , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/imunologia , Transdução de Sinais
4.
Plant Mol Biol ; 102(6): 615-624, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31997111

RESUMO

KEY MESSAGE: PTR2 in Arabidopsis thaliana is negatively regulated by ABI4 and plays a key role in water uptake by seeds, ensuring that imbibed seeds proceed to germination. Peptide transporters (PTRs) transport nitrogen-containing substrates in a proton-dependent manner. Among the six PTRs in Arabidopsis thaliana, the physiological role of the tonoplast-localized, seed embryo abundant PTR2 is unknown. In the present study, a molecular physiological analysis of PTR2 was conducted using ptr2 mutants and PTR2CO complementation lines. Compared with the wild type, the ptr2 mutant showed ca. 6 h delay in testa rupture and consequently endosperm rupture because of 17% lower water content and 10% higher free abscisic acid (ABA) content. Constitutive overexpression of the PTR2 gene under the control of the Cauliflower mosaic virus (CaMV) 35S promoter in ptr2 mutants rescued the mutant phenotypes. After cold stratification, a transient increase in ABA INSENSITIVE4 (ABI4) transcript levels during induction of testa rupture was followed by a similar increase in PTR2 transcript levels, which peaked prior to endosperm rupture. The PTR2 promoter region containing multiple CCAC motifs was recognized by ABI4 in electrophoretic mobility shift assays, and PTR2 expression was repressed by 67% in ABI4 overexpression lines compared with the wild type, suggesting that PTR2 is an immediate downstream target of ABI4. Taken together, the results suggest that ABI4-dependent temporal regulation of PTR2 expression may influence water status during seed germination to promote the post-germinative growth of imbibed seeds.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Transporte Biológico/fisiologia , Germinação/fisiologia , Proteínas de Membrana Transportadoras/metabolismo , Sementes/metabolismo , Água/metabolismo , Ácido Abscísico/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Germinação/genética , Mutação , Fenótipo , Regiões Promotoras Genéticas , Fatores de Transcrição/metabolismo
5.
J Pathol ; 243(3): 307-319, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28741662

RESUMO

Most anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancers (NSCLCs) show good clinical response to ALK inhibitors. However, some ALK-rearranged NSCLC patients show various primary responses with unknown reasons. Previous studies focused on the clinical aspects of ALK fusions in small cohorts, or were conducted in vitro and/or in vivo to investigate the function of ALK. One of the suggested theories describes how echinoderm microtubule-associated protein-like 4 (EML4)-ALK variants play a role towards different sensitivities in ALK inhibitors. Until now, there has been no integrated comprehensive study that dissects ALK at the molecular level in a large scale. Here, we report the largest extensive molecular analysis of 158 ALK-rearranged NSCLCs and have investigated these findings in a cell line construct experiment. We discovered that NSCLCs with EML4-ALK short forms (variant 3/others) had more advanced stage and frequent metastases than cases with the long forms (variant 1/others) (p = 0.057, p < 0.05). In vitro experiments revealed that EML4-ALK short forms show lower sensitivity to ALK inhibitors than do long forms. Clinical analysis also showed a trend for the short forms showing worse PFS. Interestingly, we found that breakpoints of ALK are evenly distributed mainly in intron 19 and almost all of them undergo a non-homologous end-joining repair to generate ALK fusions. We also discovered four novel somatic ALK mutations in NSCLC (T1151R, R1192P, A1280V, and L1535Q) that confer primary resistance; all of them showed strong resistance to ALK inhibitors, as G1202R does. Through targeted deep sequencing, we discovered three novel ALK fusion partners (GCC2, LMO7, and PHACTR1), and different ALK fusion partners showed different intracellular localization. With our findings that the EML4-ALK variants, new ALK somatic mutations, and novel ALK-fusion partners may affect sensitivity to ALK inhibitors, we stress the importance of targeted therapy to take the ALK molecular profiling into consideration. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/enzimologia , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , Proteínas Associadas aos Microtúbulos/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Feminino , Humanos , Neoplasias Pulmonares/genética , Masculino , Proteínas Associadas aos Microtúbulos/genética , Pessoa de Meia-Idade , Mutação/genética , Proteínas de Fusão Oncogênica/genética , Inibidores de Proteínas Quinases/uso terapêutico , Receptores Proteína Tirosina Quinases/genética
6.
J Craniofac Surg ; 29(7): 1983-1990, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29561490

RESUMO

OBJECTIVE: The objectives of this study were to evaluate the suppression of the nuclear factor kappa B (NF-kB) pathway by 4-hexylresorcinol (4HR), which was activated by tumor necrosis factor-α (TNF-α) in osteoblasts, and new bone formation by 4HR-incorporated porcine bone in an animal model. STUDY DESIGN: For the confirmation of successful incorporation of 4HR into porcine bone, scanning electron microscopy (SEM) and Fourier transform-infrared (FT-IR) analysis were performed. High performance liquid chromatography was performed for the analysis of the 4HR release profile from porcine bone. MC 3T3-E1 cells were used for the analysis of the NF-kB signaling pathway activation by western blotting and real-time reverse transcriptase polymerase chain reaction. New bone formation and the analysis of marker protein expression were studied in a rat calvarial critical-sized defect model. RESULTS: Both SEM and FT-IR analysis demonstrated successful incorporation of 4HR into porcine bone. Approximately 30% of 4HR was steadily released from porcine bone for 18 days. 4HR suppressed the NF-kB signaling pathway, which was activated by TNF-α application in MC 3T3-E1 cells. Histological analysis revealed that porcine bone particles with incorporated 4HR showed significantly greater new bone formation than those without 4HR at 4 and 8 weeks after operation (P < 0.05). The expression intensities of alkaline phosphatase, osteoprotegerin, and osteocalcin were also higher in the 4HR-incorporated group. CONCLUSION: The application of 4HR suppressed the NF-kB signaling pathway in osteoblasts and 4HR-containing porcine bone particles promoted new bone formation in a rat calvarial defect model.


Assuntos
Hexilresorcinol/farmacologia , NF-kappa B/metabolismo , Osteogênese/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Células 3T3 , Fosfatase Alcalina/metabolismo , Animais , Western Blotting , Masculino , Camundongos , Modelos Animais , Osteoblastos/efeitos dos fármacos , Osteocalcina/metabolismo , Osteoprotegerina/metabolismo , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Suínos , Fator de Necrose Tumoral alfa/metabolismo
7.
BMC Cancer ; 17(1): 535, 2017 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-28806950

RESUMO

BACKGROUND: Patient-derived xenograft (PDX) models are important tools in precision medicine and for the development of targeted therapies to treat cancer patients. This study aimed to evaluate our precision medicine strategy that integrates genomic profiling and preclinical drug-screening platforms, in order to personalize cancer treatments using PDX models. METHODS: We performed array-comparative genomic hybridization, microarray, and targeted next-generation sequencing analyses, in order to determine the oncogenic driver mutations. PDX cells were obtained from PDXs and subsequently screened in vitro with 17 targeted agents. RESULTS: PDX tumors recapitulated the histopathologic and genetic features of the patient tumors. Among the samples from lung cancer patients that were molecularly-profiled, copy number analysis identified unique focal MET amplification in one sample, 033 T, without RTK/RAS/RAF oncogene mutations. Although HER2 amplification in 033 T was not detected in the cancer panel, the selection of HER2-amplified clones was found in PDXs and PDX cells. Additionally, MET and HER2 overexpression were found in patient tumors, PDXs, and PDX cells. Crizotinib or EGFR tyrosine kinase inhibitor treatments significantly inhibited cell growth and impaired tumor sphere formation in 033 T PDX cells. CONCLUSIONS: We established PDX cell models using surgical samples from lung cancer patients, and investigated their preclinical and clinical implications for personalized targeted therapy. Additionally, we suggest that MET and EGFR inhibitor-based therapy can be used to treat MET and HER2-overexpressing lung cancers, without receptor tyrosine kinase /RAS/RAF pathway alterations.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Medicina de Precisão/métodos , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma de Pulmão , Animais , Antineoplásicos/farmacologia , Linhagem Celular , Crizotinibe , Modelos Animais de Doenças , Receptores ErbB/antagonistas & inibidores , Feminino , Amplificação de Genes , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos SCID , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/genética , Receptor ErbB-2/genética , Ensaios Antitumorais Modelo de Xenoenxerto
8.
J Biol Chem ; 290(47): 28502-28514, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26405033

RESUMO

Cyanobacteriochromes (CBCRs), which are exclusive to and widespread among cyanobacteria, are photoproteins that sense the entire range of near-UV and visible light. CBCRs are related to the red/far-red phytochromes that utilize linear tetrapyrrole (bilin) chromophores. Best characterized from the unicellular cyanobacterium Synechocystis sp. PCC 6803 and the multicellular heterocyst forming filamentous cyanobacteria Nostoc punctiforme ATCC 29133 and Anabaena sp. PCC 7120, CBCRs have been poorly investigated in mat-forming, nonheterocystous cyanobacteria. In this study, we sequenced the genome of one of such species, Microcoleus IPPAS B353 (Microcoleus B353), and identified two phytochromes and seven CBCRs with one or more bilin-binding cGMP-specific phosphodiesterase, adenylyl cyclase and FhlA (GAF) domains. Biochemical and spectroscopic measurements of 23 purified GAF proteins from phycocyanobilin (PCB) producing recombinant Escherichia coli indicated that 13 of these proteins formed near-UV and visible light-absorbing covalent adducts: 10 GAFs contained PCB chromophores, whereas three contained the PCB isomer, phycoviolobilin (PVB). Furthermore, the complement of Microcoleus B353 CBCRs is enriched in near-UV and violet sensors, but lacks red/green and green/red CBCRs that are widely distributed in other cyanobacteria. We hypothesize that enrichment in short wavelength-absorbing CBCRs is critical for acclimation to high-light environments where this organism is found.


Assuntos
Proteínas de Bactérias/genética , Cianobactérias/genética , Genoma Bacteriano , Raios Ultravioleta , Cianobactérias/metabolismo , Fotobiologia
9.
Biochem Biophys Res Commun ; 469(1): 94-100, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26592665

RESUMO

The function of PSMC5 (proteasome 26S subunit, ATPase 5) in tumors, particularly with respect to cancer radioresistance, is not known. Here, we identified PSMC5 as a novel radiosensitivity biomarker, demonstrating that radiosensitive H460 cells were converted to a radioresistance phenotype by PSMC5 depletion. Exposure of H460 cells to radiation induced a marked accumulation of cell death-promoting reactive oxygen species, but this effect was blocked in radiation-treated H460 PSMC5-knockdown cells through downregulation of the p53-p21 pathway. Interestingly, PSMC5 depletion in H460 cells enhanced both AKT activation and MDM2 transcription, thereby promoting the degradation of p53 and p21 proteins. Furthermore, specific inhibition of AKT with triciribine or knockdown of MDM2 with small interfering RNA largely restored p21 expression in PSMC5-knockdown H460 cells. Our data suggest that PSMC5 facilitates the damaging effects of radiation in radiation-responsive H460 cancer cells and therefore may serve as a prognostic indicator for radiotherapy and molecular targeted therapy in lung cancer patients.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose/efeitos da radiação , Proteínas com Domínio LIM/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/radioterapia , Tolerância a Radiação , Fatores de Transcrição/metabolismo , ATPases Associadas a Diversas Atividades Celulares , Linhagem Celular Tumoral , Relação Dose-Resposta à Radiação , Humanos , Neoplasias Pulmonares/patologia , Complexo de Endopeptidases do Proteassoma , Dosagem Radioterapêutica , Resultado do Tratamento
10.
Plant Cell ; 25(10): 3944-60, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24151298

RESUMO

Angiosperms require light for chlorophyll biosynthesis because one reaction in the pathway, the reduction of protochlorophyllide (Pchlide) to chlorophyllide, is catalyzed by the light-dependent protochlorophyllide oxidoreductase (POR). Here, we report that Cell growth defect factor1 (Cdf1), renamed here as chaperone-like protein of POR1 (CPP1), an essential protein for chloroplast development, plays a role in the regulation of POR stability and function. Cdf1/CPP1 contains a J-like domain and three transmembrane domains, is localized in the thylakoid and envelope membranes, and interacts with POR isoforms in chloroplasts. CPP1 can stabilize POR proteins with its holdase chaperone activity. CPP1 deficiency results in diminished POR protein accumulation and defective chlorophyll synthesis, leading to photobleaching and growth inhibition of plants under light conditions. CPP1 depletion also causes reduced POR accumulation in etioplasts of dark-grown plants and as a result impairs the formation of prolamellar bodies, which subsequently affects chloroplast biogenesis upon illumination. Furthermore, in cyanobacteria, the CPP1 homolog critically regulates POR accumulation and chlorophyll synthesis under high-light conditions, in which the dark-operative Pchlide oxidoreductase is repressed by its oxygen sensitivity. These findings and the ubiquitous presence of CPP1 in oxygenic photosynthetic organisms suggest the conserved nature of CPP1 function in the regulation of POR.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Proteínas de Cloroplastos/metabolismo , Luz , Chaperonas Moleculares/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Clorofila/biossíntese , Proteínas de Cloroplastos/genética , Cloroplastos/metabolismo , Regulação da Expressão Gênica de Plantas , Chaperonas Moleculares/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/efeitos da radiação , Protoclorifilida/metabolismo , Interferência de RNA , Nicotiana/enzimologia , Nicotiana/genética , Nicotiana/efeitos da radiação
11.
Mod Pathol ; 28(4): 468-79, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25234288

RESUMO

The success of crizotinib in ALK-positive patients has elicited efforts to find new oncogenic fusions in lung cancer. These efforts have led to the discovery of novel oncogenic fusion genes such as ROS1 and RET. However, the molecular and clinicopathologic characteristics associated with RET or ROS1 fusion, compared with ALK fusion-positive lung cancer, remain unclear. We accordingly analyzed the clinicopathologic characteristics of RET- and ROS1-fusion-positive lung adenocarcinomas. We further performed immunohistochemistry and fluorescence in situ hybridization analysis (FISH) in 15 cases of RET and 9 cases of ROS1 fusion tumors by identified NanoString's nCounter screening. RET fusion-positive patients were younger in age, never-smokers, and in early T stage; ROS1 fusion-positive patients had a higher number of never-smokers compared with patients with quintuple-negative (EGFR-/KRAS-/ALK-/ROS1-/RET-) lung adenocarcinoma. Histologically, RET and ROS1 fusion tumors share the solid signet-ring cell and mucinous cribriform pattern, as previously mentioned in the histology of ALK fusion tumors. Therefore, it can be presumed that fusion gene-associated lung adenocarcinomas share similar histologic features. In immunohistochemistry, the majority of 15 RET and 9 ROS1 fusion-positive cases showed positivity of more than moderate intensity and cytoplasmic staining for RET and ROS1 proteins, respectively. In FISH, the majority of RET and ROS1 rearrangement showed two signal patterns such as one fusion signal and two separated green and orange signals (1F1G1O) and an isolated 3' green signal pattern (1F1G). Our study has provided not only characteristics of fusion gene-associated histologic features but also a proposal for a future screening strategy that will enable clinicians to select cases needed to be checked for ROS1 and RET rearrangements based on clinicohistologic features.


Assuntos
Adenocarcinoma/genética , Rearranjo Gênico , Neoplasias Pulmonares/genética , Proteínas de Fusão Oncogênica/genética , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas c-ret/genética , Proteínas Proto-Oncogênicas/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-ret/metabolismo , Adulto Jovem
12.
Int J Cancer ; 134(10): 2424-36, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24615768

RESUMO

MET, a cell surface receptor for hepatocyte growth factor, is involved in the development of triple-negative/basal-like breast cancer (TNBC/BLBC). However, its utility as a therapeutic target in this subtype of breast cancer is poorly understood. To evaluate MET fully as a potential therapeutic target for TNBC/BLBC, we investigated the relationship between MET expression and clinical outcomes of patients with breast cancer and the functional effect of MET inhibition. Using automated immunohistochemistry (Ventana), we analyzed MET expression in 924 breast cancer patients with relevant clinicopathologic parameters. BLBC showed the strongest relationship with MET expression (57.5%, p < 0.001). High expression of MET in breast cancer resulted in poor overall survival (p = 0.001) and disease-free survival (DFS, p = 0.010). MET expression was relatively high in TNBC cell lines, and the silencing of MET via small interfering RNA reduced cell proliferation and migration. We observed reduced TNBC cell viability after treatment with the MET inhibitor PHA-665752. In the most drug-resistant cell line, MDA-MB-468, which showed elevated epidermal growth factor receptor (EGFR) expression, silencing of EGFR resulted in increased sensitivity to PHA-665752 treatment. We confirmed that PHA-665752 synergizes with the EGFR inhibitor erlotinib to decrease the viability of MDA-MB-468 cells. TNBC patients coexpressing MET and EGFR showed significantly worse DFS than that in patients expressing EGFR alone (p = 0.021). Our findings strongly suggest that MET may be a therapeutic target in TNBC and that the combined therapy targeting MET and EGFR may be beneficial for the treatment of TNBC/BLBC patients.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Receptores ErbB/antagonistas & inibidores , Terapia de Alvo Molecular/métodos , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Receptores ErbB/metabolismo , Cloridrato de Erlotinib , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Immunoblotting , Imuno-Histoquímica , Indóis/farmacologia , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Neoplasia de Células Basais/tratamento farmacológico , Neoplasia de Células Basais/genética , Neoplasia de Células Basais/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Quinazolinas/farmacologia , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sulfonas/farmacologia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo
13.
Exp Mol Pathol ; 97(3): 440-4, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25281918

RESUMO

Angiomyolipomas (AMLs) are relatively rare hamartomatous or benign tumors that occasionally occur as part of tuberous sclerosis complex (TSC). Mutations in either of the two genes, TSC1 and TSC2, have been attributed to the development of TSC. Between 1994 and January 2009, 83 patients were diagnosed with AML at the Samsung Medical Center. In that group of patients, 5 (6%) had AML with TSC (AML-TSC). Mutational analysis of the TSC2 gene was performed using 7 samples from the 5 AML-TSC patients and 14 samples from 14 patients with sporadic AML without TSC (AML-non-TSC). From this analysis, mutations in TSC genes were identified in 5 samples from the AML-TSC patients (mutation detection rate=71%) and 3 samples from AML-non-TSC patients (mutation detection rate=21%). In the case of AML-TSC, 6 mutations were found including 3 recurrent mutations and 3 novel mutations, while in the case of AML-non-TSC, 4 mutations were identified once, including 1 novel mutation. Also MLPA analysis of the TSC2 gene showed that TSC2 exon deletion is more frequently observed in AML-TSC patients than in AML-non-TSC patients. This is the first mutation and multiplex ligation-dependent probe amplification (MLPA) analyses of TSC2 in Korean AMLs that focus on TSC. This study provides data that are representative of the distribution of mutations and exon deletions at TSC genes in clinically diagnosed AML-TSC cases of the Korean population.


Assuntos
Angiomiolipoma/genética , Mutação , Esclerose Tuberosa/genética , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Animais , Análise Mutacional de DNA , Éxons , Feminino , Deleção de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex , República da Coreia , Proteína 2 do Complexo Esclerose Tuberosa , Adulto Jovem
14.
J Nanosci Nanotechnol ; 14(8): 6217-20, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25936090

RESUMO

Blue fluorescent materials based on diphenylaminofluorenylstyryl derivatives connected with the various end-capping aromatic groups were synthesized and characterized. An OLED, using (E)-9,9-diethyl-7-(4-(4-fluoronaphthalen-1-yl)styryl)-N,N-diphenyl-9 H-fluoren-2-amine(5) in emitting layer, was fabricated. This device showed the highly efficient blue emission with the maximum luminance of 5138 cd/m2, the luminous efficiency of 3.92 cd/A, the power efficiency of 3.17 lm/W, the external quantum efficiency of 2.90% at 20 mA/cm2 and CIE x, y coordinates of (0.14, 0.17).


Assuntos
Fluorenos/química , Luz , Espectroscopia de Ressonância Magnética , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Ultravioleta
15.
Proc Natl Acad Sci U S A ; 108(26): 10780-5, 2011 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-21670284

RESUMO

Positive phototaxis systems have been well studied in bacteria; however, the photoreceptor(s) and their downstream signaling components that are responsible for negative phototaxis are poorly understood. Negative phototaxis sensory systems are important for cyanobacteria, oxygenic photosynthetic organisms that must contend with reactive oxygen species generated by an abundance of pigment photosensitizers. The unicellular cyanobacterium Synechocystis sp. PCC6803 exhibits type IV pilus-dependent negative phototaxis in response to unidirectional UV-A illumination. Using a reverse genetic approach, together with biochemical, molecular genetic, and RNA expression profiling analyses, we show that the cyanobacteriochrome locus (slr1212/uirS) of Synechocystis and two adjacent response regulator loci (slr1213/uirR and the PatA-type regulator slr1214/lsiR) encode a UV-A-activated signaling system that is required for negative phototaxis. We propose that UirS, which is membrane-associated via its ETR1 domain, functions as a UV-A photosensor directing expression of lsiR via release of bound UirR, which targets the lsiR promoter. Constitutive expression of LsiR induces negative phototaxis under conditions that normally promote positive phototaxis. Also induced by other stresses, LsiR thus integrates light inputs from multiple photosensors to determine the direction of movement.


Assuntos
Proteínas de Bactérias/metabolismo , Estimulação Luminosa , Transdução de Sinais , Synechocystis/fisiologia , Raios Ultravioleta , Ensaio de Desvio de Mobilidade Eletroforética , Synechocystis/metabolismo
16.
Korean J Parasitol ; 52(6): 667-72, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25548419

RESUMO

While imported falciparum malaria has been increasingly reported in recent years in Korea, clinicians have difficulties in making a clinical diagnosis as well as in having accessibility to effective anti-malarial agents. Here we describe an unusual case of imported falciparum malaria with severe hemolytic anemia lasting over 2 weeks, clinically mimicking a coinfection with babesiosis. A 48-year old Korean man was diagnosed with severe falciparum malaria in France after traveling to the Republic of Benin, West Africa. He received a 1-day course of intravenous artesunate and a 7-day course of Malarone (atovaquone/proguanil) with supportive hemodialysis. Coming back to Korea 5 days after discharge, he was readmitted due to recurrent fever, and further treated with Malarone for 3 days. Both the peripheral blood smears and PCR test were positive for Plasmodium falciparum. However, he had prolonged severe hemolytic anemia (Hb 5.6 g/dl). Therefore, 10 days after the hospitalization, Babesia was considered to be potentially coinfected. A 7-day course of Malarone and azithromycin was empirically started. He became afebrile within 3 days of this babesiosis treatment, and hemolytic anemia profiles began to improve at the completion of the treatment. He has remained stable since his discharge. Unexpectedly, the PCR assays failed to detect DNA of Babesia spp. from blood. In addition, during the retrospective review of the case, the artesunate-induced delayed hemolytic anemia was considered as an alternative cause of the unexplained hemolytic anemia.


Assuntos
Anemia Hemolítica/etiologia , Anemia Hemolítica/patologia , Babesiose/diagnóstico , Babesiose/patologia , Malária Falciparum/diagnóstico , Malária Falciparum/patologia , Plasmodium falciparum/isolamento & purificação , Anemia Hemolítica/induzido quimicamente , Antibacterianos/uso terapêutico , Antimaláricos/uso terapêutico , Artemisininas/efeitos adversos , Artemisininas/uso terapêutico , Artesunato , Atovaquona/uso terapêutico , Azitromicina/uso terapêutico , Babesiose/complicações , Babesiose/tratamento farmacológico , Benin , Sangue/parasitologia , Coinfecção/diagnóstico , Coinfecção/patologia , Combinação de Medicamentos , França , Humanos , Coreia (Geográfico) , Malária Falciparum/complicações , Malária Falciparum/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Proguanil/uso terapêutico , Viagem , Resultado do Tratamento
17.
Food Sci Biotechnol ; 33(2): 431-439, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38222904

RESUMO

The objective of this study was to improve water solubility of the rice protein (RP) by forming complexes with anionic polysaccharides, such as sodium alginate (SA) and xanthan gum (XG). In addition, utilization of the RP complexes as an emulsifier was evaluated. The prepared RP-SA or RP-XG complexes were analyzed by measuring their particle size, ζ-potential, and water solubility as well as by confocal laser scanning microscopy. The formation of a complex between RP-SA and RP-XG improved the water solubility and dispersibility of RP over a wide range of pH values (3, 5, 7, and 9). Confocal fluorescence images showed that the aggregation of RP molecules was prevented by the formation of complexes between RP and polysaccharides. When soybean oil-in-water emulsions were prepared with complexes, RP-SA (ratio 4:1) and RP-XG(ratio 4:1) complex-stabilized emulsions were stable for 4 weeks of storage.

18.
Int J Biol Macromol ; 274(Pt 2): 133407, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38925190

RESUMO

Cyanobacteriochromes (CBCRs) are distinctive tetrapyrrole (bilin)-binding photoreceptors exclusively found in cyanobacteria. Unlike canonical phytochromes, CBCRs require only a GAF (cGMP-phosphodiesterase/adenylate cyclase/FhlA) domain for autolyase activity to form a bilin adduct via a Cys residue and cis-trans photoisomerization. Apart from the canonical Cys, which attaches covalently to C31 in the A-ring of the bilin, some GAF domains of CBCRs contain a second-Cys in the Asp-Xaa-Cys-Phe (DXCF) motif, responsible for isomerization of phycocyanobilin (PCB) to phycoviolobilin (PVB) and/or for the formation of a reversible 2nd thioether linkage to the C10. Unlike green/teal-absorbing GAF proteins lacking ligation activity, the second-Cys in another teal-absorbing lineage (DXCF blue/teal group) exhibits both isomerization and ligation activity due to the presence of the Tyr instead of His next to the canonical Cys. Herein, we discovered an atypical CBCR GAF protein, Tpl7205g1, belonging to the DXCF blue/teal group, but having His instead of Tyr next to the first-Cys. Consistent with its subfamily, the second-Cys of Tpl7205g1 did not form a thioether linkage at C10 of PCB, showing only isomerization activity. Instead of forming 2nd thioether linkage, this novel GAF protein exhibits a pH-dependent photocycle between protonated 15Z and deprotonated 15E. Site-directed mutagenesis to the GAF scaffolds revealed its combined characteristics, including properties of teal-DXCF CBCRs and red/green-absorbing CBCRs (XRG CBCRs), suggesting itself as the evolutionary bridge between the two CBCR groups. Our study thus sheds light on the expanded spectral tuning characteristics of teal-light absorbing CBCRs and enhances feasibility of engineering these photoreceptors.

19.
Transl Lung Cancer Res ; 13(2): 321-333, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38496685

RESUMO

Background: Anaplastic lymphoma kinase (ALK)-targeted tyrosine kinase inhibitors (TKIs) improve patient survival; however, some patients develop ALK-TKI resistance with unidentified mechanisms. We investigated ErbB family and c-MET expression in patients with ALK-positive non-small cell lung cancer (NSCLC) to understand their roles in the ALK-TKI response. Methods: We studied 72 patients with advanced ALK-positive NSCLC with EML4-ALK fusion variant subtyping and immunostaining for c-MET, EGFR, HER2, and HER3 on tissue specimens both pre- (primary) and post-treatment (secondary) with ALK-TKI. We investigated the association of their expression with survival outcomes and assessed the effectiveness of combining ALK and EGFR inhibitors in ALK-positive NSCLC cell lines stimulated with the HER3-specific ligand HRG1. Results: High expression of c-MET, EGFR, HER2, and HER3 was observed in 4.9%, 18.0%, 1.6%, and 25.8% of primary tumors, respectively, and 18.5%, 37.0%, 10.7%, and 35.7% of secondary tumors, respectively. HER3 overexpression in primary tumors showed inferior survival (P=0.132). In the subgroup with EML4-ALK variant 1/2 (V1/V2), HER3 overexpression was significantly associated with inferior survival in both primary and secondary tumors (P=0.022 and P=0.004, respectively). Combination treatment with lorlatinib and erlotinib significantly reduced HRG1-induced activation of RTK signaling in ALK-positive NSCLC cells. Conclusions: HER3 overexpression has potential as a prognostic marker in ALK-positive NSCLCs, including ALK-TKI naïve and treated cases, especially those with EML4-ALK V1/V2. Assessing HER3 expression may be crucial for treatment planning and outcome prediction in these patients.

20.
Pathology ; 56(5): 653-661, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38811262

RESUMO

Epidermal growth factor receptor (EGFR) exon 20 insertion mutations (E20ins) are the third most frequent mutations observed in non-small cell lung cancer, accounting for approximately 1-10% of all EGFR mutations. In the era of precision medicine and targeted therapies, consistent naming of genetic alterations is crucial to avoid confusion and errors. However, the annotation of EGFR E20ins mutations has been inconsistent, leading to confusion in the scientific literature and product documentation. In this study, our primary objective was to investigate the usage of different annotation related to EGFR E20ins in independent studies. Additionally, we assessed the distribution of EGFR E20ins mutations and estimated the detection coverage expected from each available EGFR E20ins detection assay. A total of 1,418 EGFR E20ins mutations were collected from six studies (FoundationInsights, Geneseeq Technology Inc, mobocertinib phase I/II trial, poziotinib phase II trial, sunvozertinib phase I trial, and Samsung Medical Center) and reorganised according to Human Genome Variation Society (HGVS) nomenclature. Our analysis revealed that the majority of EGFR E20ins mutations requiring correction were 'insertion' or 'deletion-insertion', which should be appropriately designated as 'duplication'. Additionally, duplicated variants were reported using different annotations in each study, and furthermore, even identical variant sequences were annotated differently within the same study. In all six studies, p.A767_V769dup and p.S768_D770dup were the most frequently observed EGFR E20ins. The Oncomine Dx Target Test showed the highest patient coverage at 77.2%, followed by the Droplex EGFR Mutation Test v2 with a patient coverage of 70.5% for EGFR E20ins patients. To ensure comprehensive coverage in real-world settings, it is essential to standardise the annotations for each variant, for example using the HGVS nomenclature. The accurate classification and analysis of drug responsiveness in EGFR E20ins necessitate consideration of the nomenclature, particularly with respect to the locations where the actual mutations occur.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Receptores ErbB , Éxons , Neoplasias Pulmonares , Medicina de Precisão , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Éxons/genética , Mutação , Mutagênese Insercional/genética , Terminologia como Assunto
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