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2.
Cancers (Basel) ; 11(5)2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31064137

RESUMO

Endoplasmic reticulum (ER) proteostasis is often altered in tumor cells due to intrinsic (oncogene expression, aneuploidy) and extrinsic (environmental) challenges. ER stress triggers the activation of an adaptive response named the Unfolded Protein Response (UPR), leading to protein translation repression, and to the improvement of ER protein folding and clearance capacity. The UPR is emerging as a key player in malignant transformation and tumor growth, impacting on most hallmarks of cancer. As such, the UPR can influence cancer cells' migration and invasion properties. In this review, we overview the involvement of the UPR in cancer progression. We discuss its cross-talks with the cell migration and invasion machinery. Specific aspects will be covered including extracellular matrix (ECM) remodeling, modification of cell adhesion, chemo-attraction, epithelial-mesenchymal transition (EMT), modulation of signaling pathways associated with cell mobility, and cytoskeleton remodeling. The therapeutic potential of targeting the UPR to treat cancer will also be considered with specific emphasis in the impact on metastasis and tissue invasion.

4.
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
5.
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
6.
Semin Cancer Biol ; 50: 42-52, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29369790

RESUMO

Cancer cells are exposed to adverse conditions within the tumor microenvironment that challenge cells to adapt and survive. Several of these homeostatic perturbations insults alter the normal function of the endoplasmic reticulum (ER), resulting in the accumulation of misfolded proteins. ER stress triggers a conserved signaling pathway known as the unfolded protein response (UPR) to cope with the stress or trigger apoptosis of damaged cells. The UPR has been described as a major driver in the acquisition of malignant characteristics that ultimately lead to cancer progression. Although, several reports describe the relevance of the UPR in tumor growth, the possible crosstalk with other cancer-related pathways is starting to be elucidated. The Forkhead Box O (FoxO) subfamily of proteins has a major role in cancer progression, where chromosomal translocations and deregulated signaling lead to loss-of-function of FoxO proteins, contributing to tumor progression. Here we discuss the homeostatic connection between the UPR and FoxO proteins and its possible implications to tumor progression and the acquisition of several hallmarks of cancer. In addition, studies linking a crosstalk between the UPR and FoxO proteins in other diseases, including neurodegeneration and metabolic disorders is provided.


Assuntos
Fatores de Transcrição Forkhead/genética , Neoplasias/genética , Proteostase/genética , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/genética , Homeostase , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Transdução de Sinais/genética , Resposta a Proteínas não Dobradas/genética
7.
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
8.
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.

9.
Mem. Inst. Oswaldo Cruz ; 111(12): 731-736, Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-829255

RESUMO

The association between colorectal cancer and human papillomavirus (HPV) infection is still unproven. The aim of this study was to investigate the presence of high-risk HPV (HR-HPV) DNA in colorectal tissues from Cuban patients. A total of 63 colorectal formalin-fixed paraffin-embedded tissues were studied (24 adenocarcinoma, 18 adenoma, and 21 colorectal tissues classified as benign colitis). DNA from colorectal samples was analysed by quantitative real-time polymerase chain reaction to detect the most clinically relevant high HR-HPV types (HPV-16, -18, -31, -33, -45, -52, and -58). Associations between histologic findings and other risk factors were also analysed. Overall, HPV DNA was detected in 23.8% (15/63) of the samples studied. Viral infections were detected in 41.7% of adenocarcinoma (10/24) and 27.7% of adenoma cases (5/18). HPV DNA was not found in any of the negative cases. An association between histological diagnosis of adenocarcinoma and HPV infection was observed (odd ratio = 4.85, 95% confidence interval = 1.40-16.80, p = 0.009). The only genotypes identified were HPV 16 and 33. Viral loads were higher in adenocarcinoma, and these cases were associated with HPV 16. This study provides molecular evidence of HR-HPV infection in colorectal adenocarcinoma tissues from Cuban patients.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Adenocarcinoma/virologia , Adenoma/virologia , Neoplasias Colorretais/virologia , DNA Viral/análise , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Cuba , Genótipo , Reação em Cadeia da Polimerase em Tempo Real , Carga Viral
10.
Mem Inst Oswaldo Cruz ; 111(12): 731-736, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27812599

RESUMO

The association between colorectal cancer and human papillomavirus (HPV) infection is still unproven. The aim of this study was to investigate the presence of high-risk HPV (HR-HPV) DNA in colorectal tissues from Cuban patients. A total of 63 colorectal formalin-fixed paraffin-embedded tissues were studied (24 adenocarcinoma, 18 adenoma, and 21 colorectal tissues classified as benign colitis). DNA from colorectal samples was analysed by quantitative real-time polymerase chain reaction to detect the most clinically relevant high HR-HPV types (HPV-16, -18, -31, -33, -45, -52, and -58). Associations between histologic findings and other risk factors were also analysed. Overall, HPV DNA was detected in 23.8% (15/63) of the samples studied. Viral infections were detected in 41.7% of adenocarcinoma (10/24) and 27.7% of adenoma cases (5/18). HPV DNA was not found in any of the negative cases. An association between histological diagnosis of adenocarcinoma and HPV infection was observed (odd ratio = 4.85, 95% confidence interval = 1.40-16.80, p = 0.009). The only genotypes identified were HPV 16 and 33. Viral loads were higher in adenocarcinoma, and these cases were associated with HPV 16. This study provides molecular evidence of HR-HPV infection in colorectal adenocarcinoma tissues from Cuban patients.


Assuntos
Adenocarcinoma/virologia , Adenoma/virologia , Neoplasias Colorretais/virologia , DNA Viral/análise , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Adulto , Cuba , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Carga Viral
11.
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
12.
J Int AIDS Soc ; 17(4 Suppl 3): 19754, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25397499

RESUMO

INTRODUCTION: Emergence of HIV-1 drug resistance may limit the sustained benefits of antiretroviral therapy (ART) in settings with limited laboratory monitoring and drug options. The objective is to implement the surveillance of drug resistance and subtypes in HIV-1 patients failing ART in Cuba. METHODS: This study compiled clinical and genotypic drug resistance data 588 ART-experienced HIV-1 patients attending a clinical center in Havana in 2009-2013. Drug resistance testing was performed as part of routine clinical care. Drug resistance mutations and levels were determined using Rega version 8.0.2. RESULTS: Eighty-three percent received solely ART containing at least three drugs. Patients from 2009 to 2010 were longer treated (median: 4.9 vs 2.7 years) and exposed to more ART regimens (median: 4 vs 2 regimens) compared to patients from 2011-2013. Nucleoside reverse transcriptase inhibitor (NRTI), non-nucleoside RTI (NNRTI) and PI mutations were present in 83.5, 77.4 and 52.0%. Full-class resistance (FCR) to NRTI, NNRTI, PI and multidrug resistance (MDR) were detected in 25.0, 33.7, 11.4 and 6.3%. FCR to NRTI, NNRTI, PI and MDR were present in 12.8, 28.7, 0 and 0% after first-line failure (164 patients) and in 23.1, 34.6, 3.8 and 3.1% after second-line failure (130 patients). Subtype B (32.5%), BG recombinants (19.6%) and CRF19_cpx (16.2%) were the most prevalent genetic forms. Subtype distribution did not change significantly between 2009-2010 and 2011-2013, except for BG recombinants that increased from 12.2 to 21.3% (p=0.002). CONCLUSIONS: Our study found a high prevalence of drug resistance and supports the need for appropriate laboratory monitoring in clinical practice and access to drug options in case of virological failure.

13.
J Low Genit Tract Dis ; 18(3): 210-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24270200

RESUMO

OBJECTIVE: This study aimed to provide information about the molecular epidemiology of human papillomavirus (HPV) in a group of Cuban women. MATERIALS AND METHODS: DNA from cervical samples was analyzed using a quantitative real-time polymerase chain reaction (PCR), which detects 6 of the clinically most relevant high-risk HPV types. Furthermore, end point PCR and sequencing were performed. Three hundred twenty-two women (211 with positive and 111 with negative cytologic results) aged between 30 and 69 years were enrolled. Risk factors associated with HPV infections and premalignant lesions were also investigated. RESULTS: HPV DNA was detected in 76.1% (245/322) of the studied population, and 34 different genotypes were found. There was an association between HPV infection and low educational level, history of oral contraceptives, menopausal stage, as well as cigarette and/or alcohol consumption. Besides, in a multivariate analysis, previous positive Pap test result and positive colposcopy finding were both predictor variables for HPV infections and for premalignant lesions. Human papillomavirus infection was found in 94.3% of women (199/211) with positive cytologic result and in 41.4% (46/111) of those with negative results, being more likely that the first group was infected with any HPV (odds ratio = 23.43; 95% CI = 11.70-46.92; p = .000). The most common genotypes were HPV types 16, 18, 31, 58, 33, and 45. All the cases with HPV positive findings had at least 1 high-risk HPV genotype. CONCLUSIONS: This is the first report of the molecular epidemiology of HPV in Cuban women, based on results from a DNA sequence and quantitative PCR. Most individuals were infected with high-risk HPV types. These findings support the inclusion of HPV vaccine in Cuba.


Assuntos
Colo do Útero/virologia , Papillomaviridae/classificação , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Adulto , Idoso , Coinfecção/epidemiologia , Cuba/epidemiologia , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Epidemiologia Molecular , Papillomaviridae/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA
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