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3.
Nat Cell Biol ; 20(8): 942-953, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30013108

RESUMO

Maintenance of endoplasmic reticulum (ER) proteostasis is controlled by a signalling network known as the unfolded protein response (UPR). Here, we identified filamin A as a major binding partner of the ER stress transducer IRE1α. Filamin A is an actin crosslinking factor involved in cytoskeleton remodelling. We show that IRE1α controls actin cytoskeleton dynamics and affects cell migration upstream of filamin A. The regulation of cytoskeleton dynamics by IRE1α is independent of its canonical role as a UPR mediator, serving instead as a scaffold that recruits and regulates filamin A. Targeting IRE1α expression in mice affected normal brain development, generating a phenotype resembling periventricular heterotopia, a disease linked to the loss of function of filamin A. IRE1α also modulated cell movement and cytoskeleton dynamics in fly and zebrafish models. This study unveils an unanticipated biological function of IRE1α in cell migration, whereby filamin A operates as an interphase between the UPR and the actin cytoskeleton.


Assuntos
Citoesqueleto de Actina/metabolismo , Movimento Celular , Endorribonucleases/metabolismo , Fibroblastos/metabolismo , Filaminas/metabolismo , Neurônios/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Endorribonucleases/deficiência , Endorribonucleases/genética , Evolução Molecular , Feminino , Filaminas/genética , Células HEK293 , Humanos , Cinética , Masculino , Camundongos , Camundongos Knockout , Neurônios/patologia , Heterotopia Nodular Periventricular/genética , Heterotopia Nodular Periventricular/metabolismo , Heterotopia Nodular Periventricular/patologia , Fosforilação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais , Resposta a Proteínas não Dobradas , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
4.
Rev. argent. microbiol ; 50(2): 136-146, jun. 2018. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-977230

RESUMO

The aim of the present study was to gather information regarding the molecular epidemiology of Human papillomavirus (HPV) and related risk factors in a group of women with low- and high-grade cervical lesions and cancer from the coastal region of Ecuador. In addition, we studied the evolution of HPV variants from the most prevalent types and provided a temporal framework for their emergence, which may help to trace the source of dissemination within the region. We analyzed 166 samples, including 57 CIN1, 95 CIN2/3 and 14 cancer cases. HPV detection and typing was done by PCR-sequencing (MY09/MY11). HPV variants and estimation of the time to most recent common ancestor (tMRCA) was assessed through phylogeny and coalescence analysis. HPV DNA was found in 54.4% of CIN1, 74.7% of CIN2/3 and 78.6% of cancer samples. HPV16 (38.9%) and HPV58 (19.5%) were the most prevalent types. Risk factors for the development of cervical lesions/cancer were the following: three or more pregnancies (OR = 4.3), HPV infection (OR = 3.7 for high-risk types; OR = 3.5 for HPV16), among others. With regard to HPV evolution, HPV16 isolates belonged to lineages A (69%) and D (31%) whereas HPV58 isolates belonged only to lineage A. The period of emergence of HPV16 was in association with human populations (tMRCA = 91 052 years for HPV16A and 27000 years for HPV16D), whereas HPV58A preceded Homo sapiens evolution (322 257 years). This study provides novel data on HPV epidemiology and evolution in Ecuador, which will be fundamental in the vaccine era.


El objetivo del presente estudio fue aportar información sobre la epidemiología molecular del virus del papiloma humano (human papillomavirus [HPV]) y los factores de riesgo asociados al desarrollo de lesiones cervicales y cáncer en mujeres de la costa del Ecuador. Además, se estudiaron la evolución de las variantes de los HPV más prevalentes y el marco temporal de su emergencia, para ayudar a rastrear la fuente de dispersión en la región. Se analizaron 166 muestras, incluyendo 57 y 95 casos de neoplasia intraepitelial cervical tipo 1 (CIN1) y tipo 2/3 (CIN2/3), respectivamente, y 14 de casos de cáncer. La detección/tipificación de HPV se realizó por PCR-secuenciación (MY09/MY11). La caracterización de variantes y la datación del ancestro común más reciente (tMRCA) se realizaron mediante filogenia y coalescencia. Se encontró ADN de HPV en el 54,4% de las muestras de CIN1, el 74,7% de las muestras de CIN2/3 y el 78,6% de las muestras de cáncer. Los tipos HPV16 (38,9%) y HPV58 (19,5%) fueron los más frecuentes. Los factores de riesgo para el desarrollo de lesiones cervicales/cáncer fueron 3 o más embarazos (OR = 4,3) e infección por HPV (O = 3,7 para HPV de alto riesgo, OR = 3,5 para HPV16), entre otros. En cuanto a la evolución viral, los aislados del HPV16 pertenecían a los linajes A (69%) y D (31%), mientras que los aislados del HPV58 pertenecían únicamente al linaje A. El período de emergencia del HPV16 estuvo asociado a poblaciones humanas (tMRCA = 91.052 años para HPV16Ay 27.000 para HPV16D), mientras que el del HPV58A precedió a la evolución de Homo sapiens (322.257 años). Este estudio proporciona datos novedosos sobre la epidemiología y la evolución del HPV en Ecuador, los cuales serán fundamentales en la era de la vacuna.


Assuntos
Feminino , Humanos , Filogenia , Neoplasias do Colo do Útero , Epidemiologia Molecular , Infecções por Papillomavirus , Papillomaviridae , DNA Viral/análise , Neoplasias do Colo do Útero/virologia , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/epidemiologia , Equador/epidemiologia
5.
Rev Argent Microbiol ; 50(2): 136-146, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29157596

RESUMO

The aim of the present study was to gather information regarding the molecular epidemiology of Human papillomavirus (HPV) and related risk factors in a group of women with low- and high-grade cervical lesions and cancer from the coastal region of Ecuador. In addition, we studied the evolution of HPV variants from the most prevalent types and provided a temporal framework for their emergence, which may help to trace the source of dissemination within the region. We analyzed 166 samples, including 57 CIN1, 95 CIN2/3 and 14 cancer cases. HPV detection and typing was done by PCR-sequencing (MY09/MY11). HPV variants and estimation of the time to most recent common ancestor (tMRCA) was assessed through phylogeny and coalescence analysis. HPV DNA was found in 54.4% of CIN1, 74.7% of CIN2/3 and 78.6% of cancer samples. HPV16 (38.9%) and HPV58 (19.5%) were the most prevalent types. Risk factors for the development of cervical lesions/cancer were the following: three or more pregnancies (OR=4.3), HPV infection (OR=3.7 for high-risk types; OR=3.5 for HPV16), among others. With regard to HPV evolution, HPV16 isolates belonged to lineages A (69%) and D (31%) whereas HPV58 isolates belonged only to lineage A. The period of emergence of HPV16 was in association with human populations (tMRCA=91052 years for HPV16A and 27000 years for HPV16D), whereas HPV58A preceded Homo sapiens evolution (322257 years). This study provides novel data on HPV epidemiology and evolution in Ecuador, which will be fundamental in the vaccine era.


Assuntos
Epidemiologia Molecular , Infecções por Papillomavirus , Filogenia , Neoplasias do Colo do Útero , DNA Viral/análise , Equador/epidemiologia , Feminino , Humanos , Papillomaviridae , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/genética , Neoplasias do Colo do Útero/virologia
6.
Infect Agent Cancer ; 12: 5, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28115985

RESUMO

BACKGROUND: An association between HPV infection and progression to anal squamous intraepithelial lesions (ASIL) has been established, specifically in high-risk populations such as HIV-infected men. In this population, anal cancer is one of the most common non-AIDS-defining malignancies. METHODS: A cross-sectional study to detect anal lesions and HPV infection was performed. Anal mucosa samples were collected from 56 HIV-infected men from Cuba. The cytological diagnosis was done according to Bethesda 2001 System. HPV DNA detection was determined by qPCR for six high-risk HPV types and end point PCR for low-risk HPV types (6 and 11). The end point PCR with nucleotide sequencing technique was achieved to detect other genotypes of HPV not included in the qPCR in those samples negative for HPV- 6 and 11 or negative for the six genotypes identified in the qPCR. RESULTS: Cytological diagnosis identified 53 of 56 (95%) men with abnormal anal cytology. Among those, 26% (14/53) had atypical squamous cells of undetermined significance (ASC-US), 4% (2/53) had atypical squamous cells of undetermined significance cannot exclude high-grade lesions (ASC-H), 64% (34/53) had low-grade squamous intraepithelial lesions (LSIL), and 6% (3/53) had high-grade squamous intraepithelial lesions (HSIL). HPV DNA was detected in 89% (50/56) of men and 79% had at least one of the high-risk HPV types. HPV- 16 was the most common genotype (52%), while HPV-18 was the most frequently detected genotype in men with HSIL. We found statistically significant differences in the HPV viral loads with respect to the cytology results (p = 0.0006) and that the practice of receptive anal sex was a risk factor for anal HPV infection (p = 0.032). CONCLUSION: This study shows a high prevalence of ASIL and high-risk HPV infections in the study group and is the first study showing the distribution of HPV genotypes in HIV infected Cuban men with abnormal anal cytology. This information may be of importance for local decision makers to improve prevention strategies, including the introduction of HPV vaccine in Cuba.

7.
Cancer Res ; 75(15): 3032-42, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26069249

RESUMO

Immune escape is a hallmark of cancer, but whether it relies upon extrinsic immune-selective pressure or is inherently orchestrated by oncogenic pathways is unresolved. To address this question, we took advantage of an in vitro model of sequentially transformed human mesenchymal stem cells (hMSC). Neoplastic transformation in this model increased the natural immune-evasive properties of hMSC, both by reducing their immunogenicity and by increasing their capacity to inhibit mitogen-driven T-cell proliferation. We also found that IFNγ signaling was globally affected in transformed hMSC. As a consequence, the natural inhibitory effect of hMSC on T-cell proliferation switched from an inducible mechanism depending on IFNγ signaling and mediated by indoleamine 2,3-dioxygenase to a constitutive mechanism that relied upon IL1ß involving both secreted and membrane-expressed molecules. After transformation, increased IL1ß expression both sustained the immunosuppressive properties of hMSC and increased their tumorigenicity. Thus, in this model system, IL1ß acted as intrinsic inflammatory mediator that exerted an autocrine influence on tumor growth by coordinately linking immune escape and tumorigenicity. Collectively, our findings show how oncogenes directly orchestrate inflammation and immune escape to drive the multistep process of cancer progression, independently of any need for immunoediting in the tumor microenvironment.


Assuntos
Inflamação/patologia , Células-Tronco Mesenquimais/imunologia , Células-Tronco Mesenquimais/patologia , Animais , Transformação Celular Neoplásica , Células Cultivadas , Humanos , Evasão da Resposta Imune/fisiologia , Inflamação/imunologia , Interferon gama/metabolismo , Interleucina-1beta/metabolismo , Camundongos Nus , Transdução de Sinais , Linfócitos T/metabolismo , Linfócitos T/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
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