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1.
Int J Clin Oncol ; 2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38797782

RESUMO

BACKGROUND: Nivolumab plus ipilimumab (NIVO + IPI) is the first-line treatment for patients with metastatic renal cell carcinoma (mRCC). While approximately 40% of patients treated with NIVO + IPI achieve a durable response, 20% develop primary resistance with severe consequences. Therefore, there is a clinical need for criteria to select patients suitable for NIVO + IPI therapy to optimize its therapeutic efficacy. Accordingly, our aim was to evaluate the association between candidate biomarkers measured before treatment initiation and survival. METHODS: This was a multi-institutional, retrospective, cohort study of 183 patients with mRCC treated with systematic therapies between August 2015 and July 2023. Of these, 112 received NIVO + IPI as first-line therapy: mean age, 68 years; men, 83.0% (n = 93), and clear cell histology, 80.4% (n = 90). Univariable and multivariable analyses were used to evaluate associations between biomarkers and survival. RESULTS: On univariate analysis, high C-reactive protein and systemic index, a high neutrophil-to-lymphocyte and platelet-to-lymphocyte ratio, and a low lymphocyte-to-monocyte ratio (LMR) were associated with shorter overall survival (OS). On multivariable analysis, a LMR ≤ 3 was retained as an independent factor associated to shorter OS with the highest accuracy (C-index, 0.656; hazard ratio, 7.042; 95% confidence interval, 2.0-25.0; p = 0.002). CONCLUSION: A low LMR may identify patients who would be candidate for NIVO + IPI therapy for mRCC.

2.
Int J Clin Oncol ; 28(11): 1530-1537, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37552353

RESUMO

BACKGROUND: Although nivolumab plus ipilimumab is the standard treatment for metastatic renal cell carcinoma (RCC), its efficacy and safety in older patients remain unclear. Therefore, this study aimed to assess the clinical outcomes of nivolumab plus ipilimumab for metastatic RCC in patients aged ≥ 75 years. METHODS: We enrolled 120 patients with metastatic RCC treated with nivolumab plus ipilimumab from August 2015 to January 2023. Objective response rates (ORRs) were compared between patients aged < 75 and ≥ 75 years. Progression-free survival (PFS), overall survival (OS), and adverse events were compared between the groups. Adverse events were evaluated according to the Response Evaluation Criteria in Solid Tumors 1.1. RESULTS: Among the patients, 57 and 63 were classified as intermediate and poor risk, respectively, and one could not be classified. The median follow-up duration after the initiation of treatment was 16 months. The patient characteristics between the groups, except for age, were not significantly different. Intergroup differences in ORR (42% vs. 40%; p = 0.818), PFS (HR: 0.820, 95% CI 0.455-1.479; p = 0.510), and median OS (HR: 1.492, 95% CI 0.737-3.020; p = 0.267) were not significant. The incidence of adverse events (50% vs. 67%; p = 0.111) and nivolumab plus ipilimumab discontinuation due to adverse events was not significantly different between the groups (14% vs. 13%; p = 0.877). CONCLUSIONS: The effectiveness of nivolumab plus ipilimumab was comparable between patients with metastatic RCC aged < 75 and those ≥ 75 years with respect to their ORRs, PFS, OS, and adverse event rates.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Idoso , Carcinoma de Células Renais/patologia , Nivolumabe/efeitos adversos , Ipilimumab/efeitos adversos , Neoplasias Renais/patologia , Intervalo Livre de Progressão , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
3.
Cancer Med ; 12(16): 16837-16845, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37403728

RESUMO

BACKGROUND: Nivolumab plus ipilimumab (NIVO+IPI) is the first-line treatment for patients with metastatic renal cell carcinoma (mRCC). Approximately 40% of patients achieve a durable response; however, 20% develop primary resistant disease (PRD) to NIVO+IPI, about which little is known in patients with mRCC. Therefore, this investigation aimed to evaluate the clinical implication of PRD in patients with mRCC to select better candidates in whom NIVO+IPI can be initiated as first-line therapy. METHODS: This multi-institutional retrospective cohort study used data collected between August 2015 and January 2023. In total, 120 patients with mRCC treated with NIVO+IPI were eligible. Associations between immune-related adverse events and progression-free survival, overall survival (OS), and objective response rate were analyzed. The relationship between other clinical factors and outcomes was also evaluated. RESULTS: The median observation period was 16 months (interquartile range, 5-27). The median age at NIVO+IPI initiation was 68 years in the male-dominant population (n = 86, 71.7%), and most patients had clear cell histology (n = 104, 86.7%). PRD was recorded in 26 (23.4%) of 111 investigated patients during NIVO+IPI therapy. Patients who experienced PRD showed worse OS (hazard ratio: 4.525, 95% confidence interval [CI]: 2.315-8.850, p < 0.001). Multivariable analysis showed that lymph node metastasis (LNM) (odds ratio: 4.274, 95% CI: 1.075-16.949, p = 0.039) was an independent risk factor for PRD. CONCLUSIONS: PRD was strongly correlated with worse survival rates. LNM was independently associated with PRD in patients with mRCC receiving NIVO+IPI as first-line therapy and might indicate that a candidate will not benefit from NIVO+IPI.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Masculino , Idoso , Nivolumabe/efeitos adversos , Ipilimumab/efeitos adversos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/etiologia , Estudos Retrospectivos , Neoplasias Renais/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
4.
Anat Sci Int ; 98(4): 611-617, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37046035

RESUMO

Variations appearing in biceps brachii muscle are common with accessory head, different origins, variant insertion, and different pattern of nerve innervation. However, variations appearing in both origin and insertion, and with other anomalous morphology at the same time are seldom. Here we report a complex variational case on the right arm of a 91-year-old Japanese female cadaver. The complex variations included (1) the biceps brachii muscle bifurcated at its distal ending; (2) the long head had its own tendon, which divided into two parts, i.e., a lateral part fused into the fascia between the brachioradialis and extensor carpi brevis, and a medial part attached to the radius about one centimeter ahead of the radial tuberosity; (3) the short head had an accessory origin from the shoulder capsule; (4) the bicipital aponeurosis was of two parts with an anterior superior layer formed by the long head and a posterior deep one formed by the short head; (5) the musculocutaneous nerve was especially underdeveloped that only innervated the coracobrachialis; (6) the existence of communicating branch between the musculocutaneous and median nerves, and the median nerve issued muscular branches to the biceps brachii and brachialis muscles, and (7) the brachioradial muscle had two accessory muscular bundles that originated from the fascia of the brachial muscle (proximal one) and from the bicipital aponeurosis (distal one).


Assuntos
Aponeurose , Tendões , Humanos , Feminino , Idoso de 80 Anos ou mais , Aponeurose/anatomia & histologia , Tendões/anatomia & histologia , Músculo Esquelético/anatomia & histologia , Fáscia , Punho , Cadáver , Nervo Musculocutâneo/anormalidades
5.
Anat Sci Int ; 98(1): 99-106, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35798911

RESUMO

In the present study, four types of variations of the flexor carpi radialis with accessory muscular bundles were classified depending on the origin of the accessory muscular bundle and relationships with the bicipital aponeurosis, biceps brachii, pronator teres, and coracobrachialis. Six types of insertions of the tendon of the flexor carpi radialis were also divided according to their inserted positions on the carpal and metacarpal bones. An accessory muscular bundle of the flexor carpi radialis was found in 4 (1 female and 3 males) of 68 cadavers (5.88%), with five examples in 136 arms (3.68%). It was bilateral in one cadaver and unilateral (two on the right and one on the left) in three. The insertion of the flexor carpi radialis tendon was not only on the proximal surface of the base of the second metacarpal bone but also on the third metacarpal bone, the tubercle of the trapezium, and the scaphoid. These findings and classifications are important in anatomical education, and have important significances in clinical diagnosis and therapies.


Assuntos
Antebraço , Músculo Esquelético , Masculino , Feminino , Humanos , Músculo Esquelético/anormalidades , Antebraço/anatomia & histologia , Tendões/anatomia & histologia , Punho , Braço , Cadáver
6.
Anat Sci Int ; 95(2): 293-296, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31848973

RESUMO

A variation of the flexor carpi radialis with an excessive muscular bundle was found on the right forearm of a Japanese male cadaver. The flexor carpi radialis had two heads, medial one arising from the medial epicondyle of the humerus, and the other, a variant excessive muscular bundle, arising from the bicipital aponeurosis deep at the medial edge of the tendon of biceps brachii. There was also a muscular slip between the pronator teres and lateral head of flexor carpi radialis. The insertion of the ending tendon of the flexor carpi radialis was also variant, which was not only inserted into the base of the second metacarpal bone, but into the proximal surface of the scaphoid and the tubercle of trapezium. The excessive muscular bundle might be a residual muscular slip which connects between the distal part of the biceps brachii and the initial part of the flexor carpi radialis during the early embryonic development.


Assuntos
Músculo Esquelético/anormalidades , Punho , Cadáver , Humanos , Masculino
7.
World J Exp Med ; 9(2): 14-31, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31938690

RESUMO

BACKGROUND: ATP-sensitive K+ (KATP) channels were originally found in cardiac myocytes by Noma in 1983. KATP channels were formed by potassium ion-passing pore-forming subunits (Kir6.1, Kir6.2) and regulatory subunits SUR1, SU2A and SUR2B. A number of cells and tissues have been revealed to contain these channels including hepatocytes, but detailed localization of these subunits in different types of liver cells was still uncertain. AIM: To investigate the expression of KATP channel subunits in rat liver and their localization in different cells of the liver. METHODS: Rabbit anti-rat SUR1 peptide antibody was raised and purified by antigen immunoaffinity column chromatography. Four of Sprague-Dawley rats were used for liver protein extraction for immunoblot analysis, seven of them were used for immunohistochemistry both for the ABC method and immunofluorescence staining. Four of Wistar rats were used for the isolation of hepatic stellate cells (HSCs) and Kupffer cells for both primary culture and immunocytochemistry. RESULTS: Immunoblot analysis showed that the five kinds of KATP channel subunits, i.e. Kir6.1, Kir6.2, SUR1, SUR2A, and SUR2B, were detected in liver. Immunohistochemical staining showed that Kir6.1 and Kir6.2 were weakly to moderately expressed in parenchymal cells and sinusoidal lining cells, while SUR1, SUR2A, and SUR2B were mainly localized to sinusoidal lining cells, such as HSCs, Kupffer cells, and sinusoidal endothelial cells. Immunoreactivity for SUR2A and SUR2B was expressed in the hepatocyte membrane. Double immunofluorescence staining further showed that the pore-forming subunits Kir6.1 and/or Kir6.2 colocalized with GFAP in rat liver sections and primary cultured HSCs. These KATP channel subunits also colocalized with CD68 in liver sections and primary cultured Kupffer cells. The SUR subunits colocalized with GFAP in liver sections and colocalized with CD68 both in liver sections and primary cultured Kupffer cells. In addition, five KATP channel subunits colocalized with SE-1 in sinusoidal endothelial cells. CONCLUSION: Observations from the present study indicated that KATP channel subunits expressed in rat liver and the diversity of KATP channel subunit composition might form different types of KATP channels. This is applicable to hepatocytes, HSCs, various types of Kupffer cells and sinusoidal endothelial cells.

8.
Anat Sci Int ; 93(1): 154-159, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29067619

RESUMO

The vestibulocochlear organ is composed of tiny complex structures embedded in the petrous part of the temporal bone. Landmarks on the temporal bone surface provide the only orientation guide for dissection, but these need to be removed during the course of dissection, making it difficult to grasp the underlying three-dimensional structures, especially for beginners during gross anatomy classes. We report herein an attempt to produce a transparent three-dimensional-printed model of the human ear. En bloc samples of the temporal bone from donated cadavers were subjected to computed tomography (CT) scanning, and on the basis of the data, the surface temporal bone was reconstructed with transparent resin and the vestibulocochlear organ with white resin to create a 1:1.5 scale model. The carotid canal was stuffed with red cotton, and the sigmoid sinus and internal jugular vein were filled with blue clay. In the inner ear, the internal acoustic meatus, cochlea, and semicircular canals were well reconstructed in detail with white resin. The three-dimensional relationships of the semicircular canals, spiral turns of the cochlea, and internal acoustic meatus were well recognizable from every direction through the transparent surface resin. The anterior semicircular canal was obvious immediately beneath the arcuate eminence, and the topographical relationships of the vestibulocochlear organ and adjacent great vessels were easily discernible. We consider that this transparent temporal bone model will be a very useful aid for better understanding of the gross anatomy of the vestibulocochlear organ.


Assuntos
Orelha/anatomia & histologia , Modelos Anatômicos , Impressão Tridimensional , Osso Temporal/anatomia & histologia , Cadáver , Humanos
9.
Sci Rep ; 7(1): 13202, 2017 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-29038571

RESUMO

Alu elements are primate-specific short interspersed elements (SINEs), over 1 million copies of which are present in the human genome; thus, Alu elements are useful targets for detecting human cells. However, previous Alu-based techniques for detecting human genomic DNA do not reach the theoretical limits of sensitivity and specificity. In this study, we developed a highly sensitive and specific Alu-based real-time PCR method for discriminating human cells from rodent cells, using a primer and probe set carefully designed to avoid possible cross-reactions with rodent genomes. From 100 ng of mixed human and rodent genomes, 1 fg of human genome, equivalent to 1 human cell in 100 million rodent cells, was detectable. Furthermore, in vivo mouse subrenal capsule xenotransplantation assays revealed that 10 human cells per mouse organ were detectable. In addition, after intravenous injection of human mesenchymal stem cells into NOD/SCID mice via tail vein, the biodistribution of human cells was trackable in the mouse lungs and kidneys for at least 1 week. Our findings indicate that our primer and probe set is applicable for the quantitative detection of tiny amounts of human cells, such as xenotransplanted human cancer or stem cells, in rodents.


Assuntos
Elementos Alu/genética , Animais , Genoma Humano/genética , Humanos , Rim/citologia , Rim/metabolismo , Pulmão/citologia , Pulmão/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Reação em Cadeia da Polimerase em Tempo Real
10.
Clin Anat ; 30(6): 703-710, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28459129

RESUMO

Because the vestibulocochlear organs are tiny and complex, and are covered by the petrous part of the temporal bone, they are very difficult for medical students to dissect and visualize during gross anatomy classes. Here, we report a time-saving and fail-safe procedure we have devised, using a hand-held hobby router. Nine en bloc temporal bone samples from donated human cadavers were used as trial materials for devising an appropriate procedure for dissecting the vestibulocochlear organs. A hand-held hobby router was used to cut through the temporal bone. After trials, the most time-saving and fail-safe method was selected. The performance of the selected method was assessed by a survey of 242 sides of 121 cadavers during gross anatomy classes for vestibulocochlear dissection. The assessment was based on the observation ratio. The best procedure appeared to be removal of the external acoustic meatus roof and tympanic cavity roof together with removal of the internal acoustic meatus roof. The whole procedure was completed within two dissection classes, each lasting 4.5 hr. The ratio of surveillance for the chorda tympani and three semicircular canals by students was significantly improved during 2013 through 2016. In our dissection class, "removal of the external acoustic meatus roof and tympanic cavity roof together with removal of the internal acoustic meatus roof" was the best procedure for students in the limited time available. Clin. Anat. 30:703-710, 2017. © 2017Wiley Periodicals, Inc.


Assuntos
Anatomia/educação , Dissecação/métodos , Orelha Interna/anatomia & histologia , Educação de Graduação em Medicina/métodos , Cadáver , Dissecação/instrumentação , Orelha/anatomia & histologia , Humanos , Osso Temporal , Fatores de Tempo , Estudos de Tempo e Movimento
11.
Okajimas Folia Anat Jpn ; 94(3): 119-124, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29681590

RESUMO

In the case of anatomical dissection as part of medical education, it is difficult for medical students to find the ciliary ganglion (CG) since it is small and located deeply in the orbit between the optic nerve and the lateral rectus muscle and embedded in the orbital fat. Here, we would like to introduce simple ways to find the CG by 1): tracing the sensory and parasympathetic roots to find the CG from the superior direction above the orbit, 2): transecting and retracting the lateral rectus muscle to visualize the CG from the lateral direction of the orbit, and 3): taking out whole orbital structures first and dissecting to observe the CG. The advantages and disadvantages of these methods are discussed from the standpoint of decreased laboratory time and students as beginners at orbital anatomy.


Assuntos
Dissecação/métodos , Gânglios Parassimpáticos/cirurgia , Órbita/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Pathol Int ; 64(1): 1-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24471964

RESUMO

Mesenchymal stem cells (MSCs) have been presumed to include a subpopulation of pluripotent-like cells as they differentiate not only into the same mesodermal-lineage cells but also into ectodermal- and endodermal-lineage cells and exert tissue regenerative effects in a wide variety of tissues. A novel type of pluripotent stem cell, Multilineage-differentiating stress enduring (Muse) cells, was recently discovered in mesenchymal tissues such as the bone marrow, adipose tissue, dermis and connective tissue of organs, as well as in cultured fibroblasts and bone marrow-MSCs. Muse cells are able to differentiate into all three germ layers from a single cell and to self-renew, and yet exhibit non-tumorigenic and low telomerase activities. They can migrate to and target damaged sites in vivo, spontaneously differentiate into cells compatible with the targeted tissue, and contribute to tissue repair. Thus, Muse cells may account for the wide variety of differentiation abilities and tissue repair effects that have been observed in MSCs. Muse cells are unique in that they are pluripotent stem cells that belong in the living body, and are thus assumed to play an important role in 'regenerative homeostasis' in vivo.


Assuntos
Células da Medula Óssea/citologia , Diferenciação Celular , Linhagem da Célula/fisiologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Pluripotentes/citologia , Animais , Carcinogênese/patologia , Humanos
13.
Proc Natl Acad Sci U S A ; 108(24): 9875-80, 2011 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-21628574

RESUMO

The stochastic and elite models have been proposed for the mechanism of induced pluripotent stem (iPS) cell generation. In this study we report a system that supports the elite model. We previously identified multilineage-differentiating stress-enduring (Muse) cells in human dermal fibroblasts that are characterized by stress tolerance, expression of pluripotency markers, self-renewal, and the ability to differentiate into endodermal-, mesodermal-, and ectodermal-lineage cells from a single cell. They can be isolated as stage-specific embryonic antigen-3/CD105 double-positive cells. When human fibroblasts were separated into Muse and non-Muse cells and transduced with Oct3/4, Sox2, Klf4, and c-Myc, iPS cells were generated exclusively from Muse cells but not from non-Muse cells. Although some colonies were formed from non-Muse cells, they were unlike iPS cells. Furthermore, epigenetic alterations were not seen, and some of the major pluripotency markers were not expressed for the entire period during iPS cell generation. These findings were confirmed further using cells transduced with a single polycistronic virus vector encoding all four factors. The results demonstrate that in adult human fibroblasts a subset of preexisting adult stem cells whose properties are similar in some respects to those of iPS cells selectively become iPS cells, but the remaining cells make no contribution to the generation of iPS cells. Therefore this system seems to fit the elite model rather than the stochastic model.


Assuntos
Diferenciação Celular , Linhagem da Célula , Fibroblastos/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Adaptação Fisiológica , Adulto , Animais , Antígenos CD/metabolismo , Antígenos de Superfície/metabolismo , Antígenos Glicosídicos Associados a Tumores/metabolismo , Linhagem Celular , Células Cultivadas , Derme/citologia , Endoglina , Fibroblastos/metabolismo , Humanos , Imuno-Histoquímica , Células-Tronco Pluripotentes Induzidas/metabolismo , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Receptores de Superfície Celular/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Antígenos Embrionários Estágio-Específicos/metabolismo , Estresse Fisiológico , Transfecção
14.
Proc Natl Acad Sci U S A ; 107(19): 8639-43, 2010 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-20421459

RESUMO

We found adult human stem cells that can generate, from a single cell, cells with the characteristics of the three germ layers. The cells are stress-tolerant and can be isolated from cultured skin fibroblasts or bone marrow stromal cells, or directly from bone marrow aspirates. These cells can self-renew; form characteristic cell clusters in suspension culture that express a set of genes associated with pluripotency; and can differentiate into endodermal, ectodermal, and mesodermal cells both in vitro and in vivo. When transplanted into immunodeficient mice by local or i.v. injection, the cells integrated into damaged skin, muscle, or liver and differentiated into cytokeratin 14-, dystrophin-, or albumin-positive cells in the respective tissues. Furthermore, they can be efficiently isolated as SSEA-3(+) cells. Unlike authentic ES cells, their proliferation activity is not very high and they do not form teratomas in immunodeficient mouse testes. Thus, nontumorigenic stem cells with the ability to generate the multiple cell types of the three germ layers can be obtained through easily accessible adult human mesenchymal cells without introducing exogenous genes. These unique cells will be beneficial for cell-based therapy and biomedical research.


Assuntos
Células-Tronco Adultas/citologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Multipotentes/citologia , Adulto , Animais , Células da Medula Óssea/citologia , Agregação Celular , Diferenciação Celular , Proliferação de Células , Humanos , Transplante de Células-Tronco Mesenquimais , Camundongos
15.
Nat Rev Mol Cell Biol ; 6(5): 413-22, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15956980

RESUMO

Catalytic RNAs, also known as ribozymes, can be engineered to optimize their activities in the intracellular environment. The introduction of a library of active ribozymes into cells, and the subsequent screening for phenotypic changes, allows the rapid identification of gene function. For the determination of gene function, ribozyme technology complements another RNA-based tool that is based on libraries of small interfering RNAs.


Assuntos
Biblioteca Gênica , Inativação Gênica , RNA Catalítico/genética , RNA Interferente Pequeno/genética , Animais , Expressão Gênica , Técnicas Genéticas
16.
J Biol Chem ; 280(27): 25687-96, 2005 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-15845550

RESUMO

We have developed an original vector library that allowed us to exploit the phenomenon of RNA interference but also allowed us to avoid the confounding effects of the interferon response. In the present work, we used our library of small interfering RNA expression vectors to examine the genes involved in apoptosis that was induced by double-stranded RNA. To our surprise, screening of our library revealed two novel double-stranded RNA-induced apoptotic pathways, a JNK/SAPK-mediated mitochondrial pathway and an ERK2-related pathway, both of which appeared to be independent of the serine-threonine protein kinase-dependent caspase pathway. We also found that MST2 and protein kinase Calpha both activated the pro-apoptotic signal mediated by ERK2. The results of our screening analysis suggested the utility of large scale screenings with libraries of small interfering RNA expression vectors.


Assuntos
Apoptose/genética , Biblioteca Gênica , Sistema de Sinalização das MAP Quinases/genética , Interferência de RNA/fisiologia , RNA de Cadeia Dupla/genética , Testes Genéticos/métodos , Vetores Genéticos , Células HeLa , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Luciferases/genética , Mitocôndrias/enzimologia , Mitocôndrias/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Transfecção , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
17.
Methods Enzymol ; 392: 97-112, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15644177

RESUMO

RNA interference (RNAi) is a conserved process in which a double-stranded RNA (dsRNA) induces sequence-specific gene silencing. Recent developments in the use of the 21-nt small interfering RNA (siRNA) have allowed the specific degradation of mRNA without induction of nonspecific effects in mammalian cells. RNAi provides a method for knocking down genes of interest and a powerful tool for studies on gene functions in various organisms. Although many vector-based siRNA expression systems have been developed for production of siRNAs in mammalian cells, many technical issues for an effective production of siRNAs still need to be resolved. In this chapter, we describe methods for construction of genetically stable and highly active siRNA expression systems and also mention some strategies to overcome serious technical problems.


Assuntos
Interferência de RNA , Sequência de Bases , DNA , Vetores Genéticos , Humanos , Regiões Promotoras Genéticas , RNA Interferente Pequeno/genética
18.
Mol Biosyst ; 1(5-6): 382-90, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16881007

RESUMO

In mammalian cells, siRNAs have been used to induce RNA interference (RNAi) in an attempt to prevent nonspecific effects (including the interferon (IFN) response) which are caused by long double-stranded RNAs (dsRNAs) of more than 30 bp. In this report, we describe a novel and simple strategy for avoiding activation of the IFN response by dsRNA. We show that modified hairpin-RNAs (mhRNAs) of more than 100 bp, with multiple specific point-mutations within the sense strand and transcribed from the U6 or tRNA(Val) promoters, can cause RNAi without inducing the IFN pathway genes. Moreover, we demonstrate that the 50-bp mhRNA vector could effectively suppress the replication of multiple hepatitis C viruses (the genomes of which differ slightly, thus the 21-bp siRNA vector failed to suppress one of them). Our findings should enhance the exploitation of RNAi in mammalian cells, especially in the field of RNAi therapy against pathogenic viruses.


Assuntos
Hepacivirus/fisiologia , Interferons/metabolismo , Interferência de RNA , Sequência de Bases , Vetores Genéticos , Células HeLa , Hepacivirus/genética , Humanos , Dados de Sequência Molecular , RNA , RNA Polimerase II , RNA Interferente Pequeno , RNA Nuclear Pequeno , RNA de Transferência , Transfecção , Replicação Viral
19.
Nucleic Acids Symp Ser (Oxf) ; (49): 91-2, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17150648

RESUMO

Mechanism of action of hammerhead ribozymes has been investigated and their intracellular activities have been improved. Based on the improved ribozymes and more recently discovered natural RNAi, we have created libraries of both ribozymes and short hairpin RNAs (shRNAs). The introduction of a library of active ribozymes or shRNAs into cells, and the subsequent screening for phenotypic changes, allows the rapid identification of gene function.


Assuntos
Técnicas de Química Combinatória , Interferência de RNA , RNA Catalítico/química , RNA não Traduzido/química , Animais , Antineoplásicos Fitogênicos/farmacologia , Humanos , Camundongos , Fenótipo
20.
Methods Mol Biol ; 252: 533-43, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15017079

RESUMO

Suppression by double-stranded RNA (dsRNA) of expression of a target gene is known as RNA interference (RNAi). Tobacco BY-2 cell suspension has been used as a model cultured plant cell, because it is possible to produce populations of tobacco BY-2 cell suspensions that are uniform and divide synchronously for functional gene analysis. Here, we describe a method to induce RNAi by introducing a hairpin-type dsRNA expression vector into BY-2 cells via electroporation. This methodology should facilitate the analysis of individual gene function in plant cells.


Assuntos
Vetores Genéticos , Plantas/genética , RNA Interferente Pequeno/genética , Animais , Sequência de Bases , Genes Reporter , Indicadores e Reagentes , Luciferases/análise , Luciferases/genética , Conformação de Ácido Nucleico , RNA de Cadeia Dupla/antagonistas & inibidores , RNA de Cadeia Dupla/genética , RNA Interferente Pequeno/farmacologia , Mapeamento por Restrição
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