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1.
Chem Asian J ; : e202400384, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647096

RESUMO

Arylacetylenes undergo anti-1,2-dizincation to afford trans-1,2-dizincioalkenes. The process employs sodium dispersion as a reducing agent and zinc chloride TMEDA complex as a reduction-resistant zinc electrophile. This reductive anti-dizincation contrasts with the conventional additive syn-dimetalation like silylzincation. The resulting dizincated alkenes undergo the cross-coupling to yield multi-substituted alkenes stereoselectively.

2.
Int J Mol Sci ; 25(6)2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38542206

RESUMO

Near-infrared photoimmunotherapy (NIR-PIT) is a novel cancer therapy based on a monoclonal antibody (mAb) conjugated to a photosensitizer (IR700Dye). The conjugate can be activated by near-infrared light irradiation, causing necrotic cell death with high selectivity. In this study, we investigated NIR-PIT using a small protein mimetic (6-7 kDa, Affibody) which has more rapid clearance and better tissue penetration than mAbs for epidermal growth factor receptor (EGFR)-positive salivary gland cancer (SGC). The level of EGFR expression was examined in vitro using immunocytochemistry and Western blotting. Cell viability was analyzed using the alamarBlue assay. In vivo, the volume of EGFR-positive tumors treated with NIR-PIT using the EGFR Affibody-IR700Dye conjugate was followed for 43 days. It was found that NIR-PIT using the EGFR Affibody-IR700Dye conjugate induced the selective destruction of EGFR-positive SGC cells and restricted the progression of EGFR-positive tumors. We expect that NIR-PIT using the EGFR Affibody-IR700Dye conjugate can efficiently treat EGFR-positive SGC and preserve normal salivary function.


Assuntos
Fototerapia , Neoplasias das Glândulas Salivares , Humanos , Linhagem Celular Tumoral , Imunoterapia , Fármacos Fotossensibilizantes/farmacologia , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Receptores ErbB , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Arthropod Struct Dev ; 71: 101210, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36206666

RESUMO

During evolution, various lineages of arthropods colonized land and independently acquired air-breathing organs. Some taxa of oniscidean isopods (Crustacea, Isopoda, Oniscidea) are the most successful crustacean lineages on land and possess organs called "lungs" or "pseudotrachea" for air-breathing in their abdominal appendages, i.e., in pleopods. Although these lungs are important for adapting to the terrestrial environment, their developmental process has not yet been elucidated. In the present study, we investigated the process of lung development in Porcellio scaber, the common rough woodlouse with pleopodal lungs in the first two pairs of pleopods. The lungs in the second pleopods developed at the manca 1 stage (immediately after hatching) and became functional at the manca 2 stage. In the first pleopods, which appear at the manca 3 stage, the lungs were gradually developed during the manca 3 stage and became functional in post-manca juveniles. In the second pleopods, epithelial invaginations led to lung development. These results suggest that some novel developmental mechanisms with epithelial invaginations and cuticle formation were acquired during terrestrialization, resulting in the development of functional lungs in the terrestrial isopod lineages.


Assuntos
Isópodes , Animais , Pulmão
4.
Water Res ; 219: 118581, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35584587

RESUMO

Polyethylene terephthalate (PET) is produced worldwide, mainly as material for plastic drink bottles. PET is produced by polymerization of purified terephthalate (PTA) or dimethyl terephthalate (DMT) with ethylene glycol. During the synthetic manufacturing processes of PTA and DMT, high organic loading wastewater is produced, which is typically treated separately by anaerobic wastewater treatment technologies. Given the high demand for PET, manufacturing plants are expanding globally, which will result in an increase in the amounts of PTA and DMT wastewater in need of treatment. In terms of effective treatment, the cotreatment of PTA and DMT wastewater has several advantages, including lower area and energy requirements. In this study, we examined the performance of an upflow anaerobic sludge blanket (UASB) reactor in cotreating PTA and DMT wastewater with high organic loading, evaluating its removal characteristics after 518 days of continuous operation. In addition, we performed a microbiome analysis of the UASB granular sludge to uncover the microbial interactions and metabolic functions within the reactor. By continuous operation, we achieved an organic removal rate of 6.6 kg m-3 day-1. In addition, we confirmed that aromatic compounds in the complex wastewater from the PTA and DMT manufacturing processes are biodegradable in the following order: benzoate > orthophthalate > terephthalate > isophthalate > p-toluic acid. 16S rRNA gene-based network analysis shows that anaerobic Woesearchaeales belonging to phylum Nanoarchaeota has a positive correlation with Methanoregula, Candidatus Methanofastidiosum, and Methanosarcina, suggesting a symbiotic relationship with methanogens in granular sludge. Shotgun metagenomic analysis revealed that terephthalate, isophthalate/orthophthalate, and benzoate were degraded by different members of Pelotomaculaceae and Syntrophorhabdaceae. According to the genomic information, we propose two new possible routes for orthophthalate degradation by the Syntrophorhabdaceae organism.


Assuntos
Esgotos , Águas Residuárias , Anaerobiose , Benzoatos , Reatores Biológicos , Ácidos Ftálicos , RNA Ribossômico 16S/genética , Eliminação de Resíduos Líquidos
5.
Int J Mol Sci ; 22(22)2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34830099

RESUMO

Near-infrared photoimmunotherapy (NIR-PIT) is a promising cancer therapy based on a monoclonal antibody conjugated to a photosensitizer (IR700Dye) that is activated by near-infrared light irradiation. We previously reported on the use of NIR-PIT with a small protein mimetic, the Affibody molecule (6-7 kDa), instead of a monoclonal antibody. In this study, we investigated a combination of NIR-PIT for HER2-positive breast cancer cells (SK-BR3, MDA-MB361, and JIMT1) with HER2 Affibody-IR700Dye conjugate and trastuzumab-IR700Dye conjugate. HER2 Affibody and trastuzumab target different epitopes of the HER2 protein and do not compete. In vitro, the combination of NIR-PIT using both HER2 Affibody-IR700Dye conjugate and trastuzumab-IR700Dye conjugate induced necrotic cell death of HER2-positive breast cancer cells without damage to HER2-negative breast cancer cells (MCF7). It was more efficient than NIR-PIT using either the HER2 Affibody-IR700Dye conjugate alone or the trastuzumab-IR700Dye conjugate alone. Additionally, this combination of NIR-PIT was significantly effective against HER2 low-expressing cancer cells, trastuzumab-resistant cells (JIMT1), and brain metastatic cells of breast cancer (MDA-MB361). Furthermore, in vivo imaging exhibited the strong fluorescence intensity of both HER2 Affibody-IR700Dye conjugates and trastuzumab-Alexa488 conjugates in HER2-positive tumor, indicating that both HER2 Affibody and trastuzumab specifically bind to HER2-positive tumors without competing with each other. In conclusion, the combination of NIR-PIT using both HER2 Affibody and trastuzumab expands the targeting scope of NIR-PIT for HER2-positive breast cancer.


Assuntos
Materiais Biomiméticos/farmacologia , Neoplasias da Mama/terapia , Imunoterapia , Fototerapia , Receptor ErbB-2/antagonistas & inibidores , Trastuzumab/farmacologia , Neoplasias da Mama/metabolismo , Feminino , Corantes Fluorescentes/farmacologia , Humanos , Células MCF-7 , Receptor ErbB-2/metabolismo
6.
Zoolog Sci ; 38(3): 203-212, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34057344

RESUMO

In bryozoans (phylum Bryozoa), representative colonial animals mostly found in marine environments, some species possess different types of individuals (heterozooids) specialized in different functions such as defense or structural support for their colonies. Among them, the best-known heterozooids are the avicularia, known to function as defenders. The differentiation processes of heterozooids, including avicularia, should be important keys to understand the evolutionary significance of bryozoans. However, the developmental process of avicularium formation remains to be fully understood. In this study, therefore, in order to understand the detailed developmental process and timing of avicularium formation, extensive observations were carried out in a bryozoan species, Bugulina californica (Cheilostomata, Bugulidae), that possesses adventitious avicularia, by performing stereomicroscopy on live materials, in addition to scanning electron microscopy and histological observations. The whole process can be divided into seven stages based on developmental events. Especially notably, at the earlier stages, there are three major budding events that produce proliferating cell masses corresponding to primordial tissues: (1) budding of the peduncle cushion at the outer margin of the distal part of a young autozooid, (2) budding of the head-part primordium from the peduncle cushion, and (3) budding of the polypide inside the head part. Experimental control of temperature showed that 20°C would be the best to maintain B. californica colonies.


Assuntos
Briozoários/crescimento & desenvolvimento , Animais , Evolução Biológica , Briozoários/genética , Briozoários/ultraestrutura , Microscopia Eletrônica de Varredura
7.
Int J Mol Sci ; 20(23)2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31757056

RESUMO

Near-infrared photoimmunotherapy (NIR-PIT) is a new and promising cancer therapy based on a monoclonal antibody conjugated to a photosensitizer which is activated by near-infrared light irradiation, causing cell death. We investigated NIR-PIT using a small protein mimetic (6-7 kDa), Affibody molecules, instead of a monoclonal antibody for HER2-overexpressing cancer. Because of its small size, the Affibody has rapid clearance, high imaging contrast, and good tumor penetration. Due to the small size of the Affibodies, which can cross the blood-brain barrier, NIR-PIT using Affibodies has the potential to extend the target cancer of NIR-PIT, including brain metastases. In vitro, NIR-PIT using HER2 Affibody-IR700Dye conjugates induced the selective destruction of HER2-overexpressing breast cancer cells without damage to control cells having low level expression of HER2. HER2-overexpressing cancer cells showed necrotic cell death and their viability maintained at low levels, even 5 days after NIR-PIT. In contrast, treatment with high concentration of HER2 Affibody-IR700Dye conjugate alone or irradiation with high dose of NIR light alone was without effect on cell viability. Affibody and IR700Dye are currently used clinically, and therefore, we would expect the current formulation to be safely and quickly transitioned into clinical trials.


Assuntos
Anticorpos Monoclonais/química , Antineoplásicos/química , Neoplasias da Mama/terapia , Imunoterapia/métodos , Fragmentos de Peptídeos/química , Fototerapia/métodos , Receptor ErbB-2/metabolismo , Anticorpos Monoclonais/imunologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Biomimética , Linhagem Celular Tumoral , Feminino , Humanos , Raios Infravermelhos , Fragmentos de Peptídeos/farmacologia , Fármacos Fotossensibilizantes/química , Ligação Proteica , Receptor ErbB-2/imunologia
8.
Biosci Biotechnol Biochem ; 83(6): 996-999, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30835638

RESUMO

Endolichenic fungi, nonobligate microfungi that live in lichen, are promising as new bioresources of pharmacological compounds. We found that norlichexanthone isolated from the endolichenic fungus in Pertusaria laeviganda exhibited high antioxidant activity. Norlichexanthone produced by endolichenic fungus had the antioxidant activity with same level of ascorbic acid. This is the first report of high antioxidant activity of norlichexanthone. Abbreviations: AAPH: 2,2'-azobis (2-methylpropionamidine) dihydrochloride; DPPH: 2,2-diphenyl-1-picrylhydrazyl; FL: fluorescein sodium salt; HPLC-PDA: high-performance liquid chromatography with photodiode array; LC-ESI-MS: liquid chromatography with electrospray ionization mass spectrometry; ORAC: oxygen radical absorbance capacity; PB: phosphate buffer; ROS: reactive oxygen species; TLC: thin-layer chromatography.


Assuntos
Antioxidantes/farmacologia , Ascomicetos/metabolismo , Líquens/microbiologia , Xantonas/metabolismo , Xantonas/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia em Camada Fina/métodos , Análise Espectral/métodos , Xantonas/isolamento & purificação
9.
Int J Mol Sci ; 20(2)2019 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-30669481

RESUMO

The accurate detection of lymph node metastases is essential for treatment success in early-stage malignant cancer. Sentinel lymph node (SLN) biopsy is the most effective procedure for detecting small or micrometastases that are undetectable by conventional imaging modalities. To demonstrate a new approach for developing a more efficient SLN biopsy procedure, we reported a two-stage imaging method combining lymphoscintigraphy and near-infrared (NIR) fluorescence imaging to depict metastatic cancer cells in SLNs in vivo. Furthermore, the theranostic potential of the combined procedure was examined by cell culture and xenograft mouse model. Anti-HER2 and anti-epidermal growth factor receptor (EGFR) affibody probes were used for NIR fluorescence imaging. Strong NIR fluorescence signal intensity of the anti-EGFR affibody probe was observed in SAS cells (EGFR positive). Radioactivity in the SLNs was clearly observed in the in vivo studies. High anti-EGFR affibody NIR fluorescence intensity was observed in the metastatic lymph nodes in mice. The addition of the IR700-conjugated anti-EGFR affibody to the culture medium decreased the proliferation of SAS cells. Decreased proliferation was shown in Ki-67 immunohistochemistry in xenograft tumors. Our data suggest that a two-stage combined imaging method using lymphoscintigraphy and affibody probes may offer the direct visualization of metastatic lymph nodes as an easily applied technique in SLN biopsy. Although further animal studies are required to assess the effect of treating lymphatic metastasis in this approach, our study results provide a foundation for the further development of this promising imaging and treatment strategy for earlier lymph node metastasis detection and treatment.


Assuntos
Imagem Molecular , Sondas Moleculares , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Proteínas Recombinantes de Fusão , Linfonodo Sentinela/diagnóstico por imagem , Linfonodo Sentinela/patologia , Nanomedicina Teranóstica , Animais , Biomarcadores Tumorais , Linhagem Celular Tumoral , Células Cultivadas , Imunofluorescência , Humanos , Imuno-Histoquímica , Metástase Linfática , Camundongos , Imagem Molecular/métodos , Neoplasias/metabolismo , Neoplasias/terapia , Espectroscopia de Luz Próxima ao Infravermelho , Nanomedicina Teranóstica/métodos
10.
Int J Mol Sci ; 19(3)2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29562708

RESUMO

We investigated the effects of targeted functionalized silica nanoparticles on the radiosensitivity of cancer cells. Better control of the local concentration of silica nanoparticles may facilitate their use as an adjuvant in conjunction with ionizing radiation to target cancer cells while preventing damage to normal cells. Hyperbranched polyamidoamine (PAMAM) was grafted onto the surface of amorphous silica nanoparticles to functionalize them. The PAMAM-coated silica nanoparticles (PCSNs) were then conjugated with fluorescent dyes. Anti-HER2 antibodies were covalently attached to the labeled PCSNs. The HER2-overexpressing SK-BR3 breast cancer cell line was incubated in medium containing the PCSN probes. After incubation; the cells were exposed to X-ray radiation. Cells were counted in all samples using cell proliferation assays; and apoptotic cells were detected. The cell survival results showed that the combination of the targeted PCSN probes and radiation reduced the survival rate of SK-BR3 cells to a greater extent than when either PCSN probes, PCSNs or radiation were applied individually. The results also showed an increase in apoptosis in the SK-BR3 cells that internalized the PCSN probes and were then irradiated. Based on these data, PCSN probes act as specific radiosensitizing agents for HER2-overexpressing cells.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Nanopartículas/química , Tolerância a Radiação , Receptor ErbB-2/metabolismo , Dióxido de Silício/química , Neoplasias da Mama/radioterapia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Sobrevivência Celular , Feminino , Fluorescência , Humanos , Lisossomos/metabolismo , Nanopartículas/ultraestrutura , Tamanho da Partícula , Poliaminas/química
11.
J Cell Biochem ; 119(2): 1475-1487, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28771803

RESUMO

A20, also referred to as tumor necrosis factor alpha (TNFα)-induced protein 3 (TNFAIP3), is an ubiquitin-editing enzyme whose expression is enhanced by NF-κB activation, and plays an important role in silencing NF-κB activity. Another well-known role for A20 is to protect cells from TNFα-induced apoptosis. Depletion of NF-κB in differentiating U937 monocytic leukemia cells is known to cause apoptotic cell death; however, much remains to be explored about the molecules that are expressed in an NF-κB-dependent manner and which support monocyte-macrophage differentiation. Using the monocytic cell line THP-1, and peripheral blood monocytes, we show here a sustained increase in A20 expression during monocyte-macrophage differentiation, which coincided with high NF-κB-dependent transcriptional activity. Depletion of NF-κB by stable expression of a super-repressor form of IκBα in THP-1 cells caused remarkable cell death during phorbol 12-myristate 13-acetate (PMA)-induced differentiation. A20 expression in these cells did not alter this NF-κB suppression, but was sufficient to protect the cells and restore the cell surface expression of a differentiation marker (CD11b) and phagocytic activity. Mutational analyses revealed that this A20 activity requires the carboxy-terminal zinc-finger domain, but not its deubiquitinase activity. Based on these findings, we conclude that A20, when ectopically expressed, can support both survival and differentiation of THP-1 cells in the absence of sustained NF-κB activity.


Assuntos
Núcleo Celular/metabolismo , NF-kappa B/genética , Ésteres de Forbol/farmacologia , Células THP-1/citologia , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Apoptose , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular , Humanos , Mutação , Inibidor de NF-kappaB alfa/genética , Inibidor de NF-kappaB alfa/metabolismo , NF-kappa B/metabolismo , Domínios Proteicos , Células THP-1/efeitos dos fármacos , Células THP-1/metabolismo , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/química , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo
12.
Pol J Radiol ; 82: 561-566, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29662586

RESUMO

BACKGROUND: Xerostomia is one of the commonest radiation-induced complications in patients with head and neck carcinoma. The aim of this study was to assess structural variations in parotid glands induced by radiation therapy in patients with oral carcinoma with contras-enhanced computed tomography (CECT). MATERIAL/METHODS: A retrospective study was performed in 41 patients with oral carcinoma who underwent CECT for head and neck malignancies before and after radiotherapy. We analyzed the relationship between parotid density variations, parotid volume change, as seen on CECT, and the mean radiation dose applied to the parotid glands in patients with oral carcinoma immediately after radiotherapy, and 2 and 3 years later. RESULTS: Immediately after radiotherapy, high-density changes on contrast-enhanced CT were observed in 70.5% of the irradiated parotids. Low-density changes due to fat degeneration were seen in 46.2% and 72.2% of the irradiated parotids 2 and 3 years after radiotherapy, respectively. The mean dose applied to the parotids with the low-density changes and without such changes 3 years after radiotherapy was 46.0 Gy and 27.7 Gy, respectively (p=0.049). Furthermore, parotid shrinkage was observed in 63.6% of the irradiated parotids. CONCLUSIONS: This study suggests that the structural variations in parotid glands induced by radiotherapy included high-density changes that were observed immediately after radiotherapy and low-density changes that were seen at late follow-up. This study should be useful for clinicians in the assessment of radiation-induced injuries in the parotids with respect to early prediction of xerostomia.

13.
Int J Mol Sci ; 17(7)2016 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-27399687

RESUMO

We sought to develop dual-modality imaging probes using functionalized silica nanoparticles to target human epidermal growth factor receptor 2 (HER2)-overexpressing breast cancer cells and achieve efficient target imaging of HER2-expressing tumors. Polyamidoamine-based functionalized silica nanoparticles (PCSNs) for multimodal imaging were synthesized with near-infrared (NIR) fluorescence (indocyanine green (ICG)) and technetium-99m ((99m)Tc) radioactivity. Anti-HER2 antibodies were bound to the labeled PCSNs. These dual-imaging probes were tested to image HER2-overexpressing breast carcinoma cells. In vivo imaging was also examined in breast tumor xenograft models in mice. SK-BR3 (HER2 positive) cells were imaged with stronger NIR fluorescent signals than that in MDA-MB231 (HER2 negative) cells. The increased radioactivity of the SK-BR3 cells was also confirmed by phosphor imaging. NIR images showed strong fluorescent signals in the SK-BR3 tumor model compared to muscle tissues and the MDA-MB231 tumor model. Automatic well counting results showed increased radioactivity in the SK-BR3 xenograft tumors. We developed functionalized silica nanoparticles loaded with (99m)Tc and ICG for the targeting and imaging of HER2-expressing cells. The dual-imaging probes efficiently imaged HER2-overexpressing cells. Although further studies are needed to produce efficient isotope labeling, the results suggest that the multifunctional silica nanoparticles are a promising vehicle for imaging specific components of the cell membrane in a dual-modality manner.


Assuntos
Verde de Indocianina/química , Nanopartículas/química , Poliaminas/química , Receptor ErbB-2/metabolismo , Tecnécio/química , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Hidrazinas/química , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Imagem Multimodal , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/química , Dióxido de Silício/química , Espectroscopia de Luz Próxima ao Infravermelho , Transplante Heterólogo
14.
J Artif Organs ; 18(2): 143-50, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25472919

RESUMO

We have succeeded in reducing the calcification of acellular aortas or valves in porcine allogeneic system by removing the DNA and phospholipids, but its further reduction is desirable. Here, the calcification of the acellular tissue was evaluated in rat subcutaneous transplantation model which is known as calcification model. Acellular samples prepared by high-hydrostatic pressure (HHP) protocols with different washing media were implanted and the calcification was monitored under micro-computed tomography for 1 and 3 months. The amount of the calcium deposition was quantitatively evaluated by atomic absorption spectroscopy. A cell culture medium showed very good cell removal ability but led to severe calcification at 1 month, and surprisingly the calcium deposition increased as the washing period increased. This calcification was suppressed by removing the DNA fraction with high DNase concentration. On the other hand, the calcification was greatly reduced when washed with saline even at low DNase concentration after 2 weeks washing. These results suggest that the ion species in the washing medium and the residual DNase cooperatively affect the tendency of in vivo calcification, which led us to the possibility of reduced calcification of acellular cardiac tissues.


Assuntos
Aorta/transplante , Tela Subcutânea/diagnóstico por imagem , Tela Subcutânea/cirurgia , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/etiologia , Microtomografia por Raio-X , Animais , Calcinose , Modelos Animais de Doenças , Pressão Hidrostática , Ratos , Suínos
15.
Clin Cancer Res ; 20(15): 4059-4074, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24919575

RESUMO

PURPOSE: Irreversible EGFR-tyrosine kinase inhibitors (TKI) are thought to be one strategy to overcome EGFR-TKI resistance induced by T790M gatekeeper mutations in non-small cell lung cancer (NSCLC), yet they display limited clinical efficacy. We hypothesized that additional resistance mechanisms that cooperate with T790M could be identified by profiling tyrosine phosphorylation in NSCLC cells with acquired resistance to reversible EGFR-TKI and harboring T790M. EXPERIMENTAL DESIGN: We profiled PC9 cells with TKI-sensitive EGFR mutation and paired EGFR-TKI-resistant PC9GR (gefitinib-resistant) cells with T790M using immunoaffinity purification of tyrosine-phosphorylated peptides and mass spectrometry-based identification/quantification. Profiles of erlotinib perturbations were examined. RESULTS: We observed a large fraction of the tyrosine phosphoproteome was more abundant in PC9- and PC9GR-erlotinib-treated cells, including phosphopeptides corresponding to MET, IGF, and AXL signaling. Activation of these receptor tyrosine kinases by growth factors could protect PC9GR cells against the irreversible EGFR-TKI afatinib. We identified a Src family kinase (SFK) network as EGFR-independent and confirmed that neither erlotinib nor afatinib affected Src phosphorylation at the activation site. The SFK inhibitor dasatinib plus afatinib abolished Src phosphorylation and completely suppressed downstream phosphorylated Akt and Erk. Dasatinib further enhanced antitumor activity of afatinib or T790M-selective EGFR-TKI (WZ4006) in proliferation and apoptosis assays in multiple NSCLC cell lines with T790M-mediated resistance. This translated into tumor regression in PC9GR xenograft studies with combined afatinib and dasatinib. CONCLUSIONS: Our results identified both codrivers of resistance along with T790M and support further studies of irreversible or T790M-selective EGFR inhibitors combined with dasatinib in patients with NSCLC with acquired T790M.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Mutação/genética , Fosfoproteínas/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Tirosina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/metabolismo , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida , Receptores ErbB/genética , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Fosforilação/efeitos dos fármacos , Análise Serial de Proteínas , Proteômica/métodos , Transdução de Sinais/efeitos dos fármacos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
16.
J Neurochem ; 125(5): 713-23, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23278181

RESUMO

Prothymosin alpha (ProTα), a nuclear protein, is implicated in the inhibition of ischemia-induced necrosis as well as apoptosis in the brain and retina. Although ProTα has multiple biological functions through distinct regions in its sequence, it has remained which region is involved in this neuroprotection. This study reported that the active core peptide sequence P30 (amino acids 49-78) of ProTα exerts its full survival effect in cultured cortical neurons against ischemic stress. Our in vivo study revealed that intravitreous administration of P30 at 24 h after retinal ischemia significantly blocks the ischemia-induced functional damages of retina at day 7. In addition, P30 completely rescued the retinal ischemia-induced ganglion cell damages at day 7 after the ischemic stress, along with partial blockade of the loss of bipolar, amacrine, and photoreceptor cells. On the other hand, intracerebroventricular (3 nmol) or systemic (1 mg/kg; i.v.) injection of P30 at 1 h after cerebral ischemia (1 h tMCAO) significantly blocked the ischemia-induced brain damages and disruption of blood vessels. Systemic P30 delivery (1 mg/kg; i.v.) also significantly ameliorated the ischemic brain caused by photochemically induced thrombosis. Taken together, this study confers a precise demonstration about the novel protective activity of ProTα-derived small peptide P30 against the ischemic damages in vitro and in vivo.


Assuntos
Isquemia Encefálica/prevenção & controle , Fármacos Neuroprotetores/uso terapêutico , Precursores de Proteínas/uso terapêutico , Doenças Retinianas/prevenção & controle , Timosina/análogos & derivados , Sequência de Aminoácidos , Animais , Isquemia Encefálica/patologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Fármacos Neuroprotetores/farmacologia , Precursores de Proteínas/genética , Precursores de Proteínas/farmacologia , Ratos , Doenças Retinianas/patologia , Timosina/genética , Timosina/farmacologia , Timosina/uso terapêutico
17.
Oncotarget ; 4(1): 9-17, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23327903

RESUMO

Our aim was to investigate both the prevalence of MET amplification in gastric cancer as well as the potential of this genetic alteration to serve as a therapeutic target in gastric cancer. MET amplification was assessed by initial screening with a PCR-based copy number assay followed by confirmatory FISH analysis in formalin-fixed, paraffin-embedded specimens of gastric cancer obtained at surgery. The effects of MET tyrosine kinase inhibitors (MET-TKIs) in gastric cancer cells with or without MET amplification were also examined. The median MET copy number in 266 cases of gastric cancer was 1.7, with a range of 0.41 to 21.3. We performed FISH analysis for the 15 cases with the highest MET copy numbers. MET amplification was confirmed in the four assessable cases with a MET copy number of at least 4, whereas MET amplification was not detected in those with a gene copy number of less than 4. The prevalence of MET amplification was thus 1.5% (4 out of 266 cases). Inhibition of MET by MET-TKIs resulted in the induction of apoptosis accompanied by attenuation of downstream MET signaling in gastric cancer cell lines with MET amplification but not in those without this genetic change. MET amplification identifies a small but clinically important subgroup of gastric cancer patients who are likely to respond to MET-TKIs. Furthermore, screening with a PCR-based copy number assay is an efficient way to reduce the number of patients requiring confirmation of MET amplification by FISH analysis.


Assuntos
Variações do Número de Cópias de DNA , Amplificação de Genes , Proteínas Proto-Oncogênicas c-met/genética , Neoplasias Gástricas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Immunoblotting , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Inclusão em Parafina , Fosforilação/efeitos dos fármacos , Reação em Cadeia da Polimerase , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/metabolismo , Piridazinas/farmacologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Triazóis/farmacologia
18.
Clin Cancer Res ; 18(22): 6219-26, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-22843788

RESUMO

PURPOSE: Anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKI) such as crizotinib show marked efficacy in patients with non-small cell lung cancer positive for the echinoderm microtubule-associated protein-like 4 (EML4)-ALK fusion protein. However, acquired resistance to these agents has already been described in treated patients, and the mechanisms of such resistance remain largely unknown. EXPERIMENTAL DESIGN: We established lines of EML4-ALK-positive H3122 lung cancer cells that are resistant to the ALK inhibitor TAE684 (H3122/TR cells) and investigated their resistance mechanism with the use of immunoblot analysis, ELISA, reverse transcription and real-time PCR analysis, and an annexin V binding assay. We isolated EML4-ALK-positive lung cancer cells (K-3) from a patient who developed resistance to crizotinib and investigated their characteristics. RESULTS: The expression of EML4-ALK was reduced at the transcriptional level, whereas phosphorylation of epidermal growth factor receptor (EGFR), HER2, and HER3 was upregulated, in H3122/TR cells compared with those in H3122 cells. This activation of HER family proteins was accompanied by increased secretion of EGF. Treatment with an EGFR-TKI induced apoptosis in H3122/TR cells, but not in H3122 cells. The TAE684-induced inhibition of extracellular signal-regulated kinase (ERK) and STAT3 phosphorylation observed in parental cells was prevented by exposure of these cells to exogenous EGF, resulting in a reduced sensitivity of cell growth to TAE684. K-3 cells also manifested HER family activation accompanied by increased EGF secretion. CONCLUSIONS: EGF-mediated activation of HER family signaling is associated with ALK-TKI resistance in lung cancer positive for EML4-ALK.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Proteínas de Fusão Oncogênica/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Crizotinibe , Humanos , Concentração Inibidora 50 , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais , Células Tumorais Cultivadas/efeitos dos fármacos
19.
Mol Cancer Ther ; 11(7): 1557-64, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22729845

RESUMO

Therapeutic strategies that target the tyrosine kinase MET hold promise for gastric cancer, but the mechanism underlying the antitumor activity of such strategies remains unclear. We examined the antitumor action of the MET tyrosine kinase inhibitor crizotinib (PF-02341066) in gastric cancer cells positive or negative for MET amplification. Inhibition of MET signaling by crizotinib or RNA interference-mediated MET depletion resulted in induction of apoptosis accompanied by inhibition of AKT and extracellular signal-regulated kinase phosphorylation in gastric cancer cells with MET amplification but not in those without it, suggesting that MET signaling is essential for the survival of MET amplification-positive cells. Crizotinib upregulated the expression of BIM, a proapoptotic member of the Bcl-2 family, as well as downregulated that of survivin, X-linked inhibitor of apoptosis protein (XIAP), and c-IAP1, members of the inhibitor of apoptosis protein family, in cells with MET amplification. Forced depletion of BIM inhibited crizotinib-induced apoptosis, suggesting that upregulation of BIM contributes to the proapoptotic effect of crizotinib. Crizotinib also exhibited a marked antitumor effect in gastric cancer xenografts positive for MET amplification, whereas it had little effect on those negative for this genetic change. Crizotinib thus shows a marked antitumor action both in vitro and in vivo specifically in gastric cancer cells positive for MET amplification.


Assuntos
Antineoplásicos/farmacologia , Amplificação de Genes , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/genética , Pirazóis/farmacologia , Piridinas/farmacologia , Neoplasias Gástricas/genética , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Apoptose/genética , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Crizotinibe , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Concentração Inibidora 50 , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirazóis/administração & dosagem , Piridinas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/tratamento farmacológico , Survivina
20.
Appl Environ Microbiol ; 78(8): 2819-29, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22327593

RESUMO

The potential for sexual reproduction in Aspergillus oryzae was assessed by investigating the presence and functionality of MAT genes. Previous genome studies had identified a MAT1-1 gene in the reference strain RIB40. We now report the existence of a complementary MAT1-2 gene and the sequencing of an idiomorphic region from A. oryzae strain AO6. This allowed the development of a PCR diagnostic assay, which detected isolates of the MAT1-1 and MAT1-2 genotypes among 180 strains assayed, including industrial tane-koji isolates. Strains used for sake and miso production showed a near-1:1 ratio of the MAT1-1 and MAT1-2 mating types, whereas strains used for soy sauce production showed a significant bias toward the MAT1-2 mating type. MAT1-1 and MAT1-2 isogenic strains were then created by genetic manipulation of the resident idiomorph, and gene expression was compared by DNA microarray and quantitative real-time PCR (qRT-PCR) methodologies under conditions in which MAT genes were expressed. Thirty-three genes were found to be upregulated more than 10-fold in either the MAT1-1 host strain or the MAT1-2 gene replacement strain relative to each other, showing that both the MAT1-1 and MAT1-2 genes functionally regulate gene expression in A. oryzae in a mating type-dependent manner, the first such report for a supposedly asexual fungus. MAT1-1 expression specifically upregulated an α-pheromone precursor gene, but the functions of most of the genes affected were unknown. The results are consistent with a heterothallic breeding system in A. oryzae, and prospects for the discovery of a sexual cycle are discussed.


Assuntos
Aspergillus oryzae/fisiologia , Genes Fúngicos Tipo Acasalamento , Sequência de Aminoácidos , Aspergillus oryzae/genética , Aspergillus oryzae/crescimento & desenvolvimento , Aspergillus oryzae/isolamento & purificação , Primers do DNA/genética , DNA Fúngico/química , DNA Fúngico/genética , Microbiologia de Alimentos , Fungos/genética , Fungos/crescimento & desenvolvimento , Fungos/fisiologia , Deleção de Genes , Perfilação da Expressão Gênica , Genótipo , Análise em Microsséries , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
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