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1.
Mol Cell ; 61(1): 98-110, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26687682

RESUMO

The molecular basis by which receptor tyrosine kinases (RTKs) recruit and phosphorylate Src Homology 2 (SH2) domain-containing substrates has remained elusive. We used X-ray crystallography, NMR spectroscopy, and cell-based assays to demonstrate that recruitment and phosphorylation of Phospholipase Cγ (PLCγ), a prototypical SH2 containing substrate, by FGF receptors (FGFR) entails formation of an allosteric 2:1 FGFR-PLCγ complex. We show that the engagement of pTyr-binding pocket of the cSH2 domain of PLCγ by the phosphorylated tail of an FGFR kinase induces a conformational change at the region past the cSH2 core domain encompassing Tyr-771 and Tyr-783 to facilitate the binding/phosphorylation of these tyrosines by another FGFR kinase in trans. Our data overturn the current paradigm that recruitment and phosphorylation of substrates are carried out by the same RTK monomer in cis and disclose an obligatory role for receptor dimerization in substrate phosphorylation in addition to its canonical role in kinase activation.


Assuntos
Fosfolipase C gama/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Cristalografia por Raios X , Receptores ErbB/metabolismo , Células HEK293 , Humanos , Hidrólise , Modelos Moleculares , Dados de Sequência Molecular , Complexos Multienzimáticos , Ressonância Magnética Nuclear Biomolecular , Fosfatidilinositóis/metabolismo , Fosfolipase C gama/química , Fosfolipase C gama/genética , Fosforilação , Ligação Proteica , Conformação Proteica , Transporte Proteico , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/química , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/química , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Relação Estrutura-Atividade , Transfecção , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Domínios de Homologia de src
2.
Neurol Sci ; 45(3): 1041-1050, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37759100

RESUMO

BACKGROUND: The Apolipoprotein E (APOE) ε4 allele is a risk factor for late-onset Alzheimer's disease (AD). However, no investigation has focused on racial differences in the longitudinal effect of APOE genotypes on CSF amyloid beta (Aß42) and tau levels in AD. METHODS: This study used data from the Alzheimer's Disease Neuroimaging Initiative (ADNI): 222 participants with AD, 264 with cognitive normal (CN), and 692 with mild cognitive impairment (MCI) at baseline and two years follow-up. We used a linear mixed model to investigate the effect of APOE-ε4-genotypes on longitudinal changes in the amyloid beta and tau levels. RESULTS: Individuals with 1 or 2 APOE ε4 alleles revealed significantly higher t-Tau and p-Tau, but lower amyloid beta Aß42 compared with individuals without APOE ε4 alleles. Significantly higher levels of log-t-Tau, log-p-Tau, and low levels of log-Aß42 were observed in the subjects with older age, being female, and the two diagnostic groups (AD and MCI). The higher p-Tau and Aß42 values are associated with poor Mini-Mental State Examination (MMSE) performance. Non-Hispanic Africa American (AA) and Hispanic participants were associated with decreased log-t-Tau levels (ß = - 0.154, p = 0.0112; ß = - 0.207, and p = 0.0016, respectively) as compared to those observed in Whites. Furthermore, Hispanic participants were associated with a decreased log-p-Tau level (ß = - 0.224, p = 0.0023) compared to those observed in Whites. There were no differences in Aß42 level for non-Hispanic AA and Hispanic participants compared with White participants. CONCLUSION: Our study, for the first time, showed that the APOE ε4 allele was associated with these biomarkers, however with differing degrees among racial groups.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Feminino , Humanos , Masculino , Doença de Alzheimer/genética , Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides , Apolipoproteína E4/genética , Apolipoproteínas E/genética , Biomarcadores , Disfunção Cognitiva/genética , Disfunção Cognitiva/diagnóstico , Fragmentos de Peptídeos , Fatores Raciais , Proteínas tau
3.
Lancet Oncol ; 24(8): e344-e354, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37541280

RESUMO

Brain metastases are an increasing global public health concern, even as survival rates improve for patients with metastatic disease. Both metastases and the sequelae of their treatment are key determinants of the inter-related priorities of patient survival, function, and quality of life, mandating a multidimensional approach to clinical care and research. At a virtual National Cancer Institute Workshop in September, 2022, key stakeholders convened to define research priorities to address the crucial areas of unmet need for patients with brain metastases to achieve meaningful advances in patient outcomes. This Policy Review outlines existing knowledge gaps, collaborative opportunities, and specific recommendations regarding consensus priorities and future directions in brain metastases research. Achieving major advances in research will require enhanced coordination between the ongoing efforts of individual organisations and consortia. Importantly, the continual and active engagement of patients and patient advocates will be necessary to ensure that the directionality of all efforts reflects what is most meaningful in the context of patient care.


Assuntos
Pesquisa Biomédica , Neoplasias Encefálicas , Estados Unidos , Humanos , Qualidade de Vida , National Cancer Institute (U.S.) , Consenso , Neoplasias Encefálicas/terapia
4.
Future Oncol ; 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36935637

RESUMO

WHAT IS THIS SUMMARY ABOUT?: This article provides a plain language summary and patient perspective of a new set of recommendations made by the European Society for Medical Oncology (ESMO for short). These recommendations are also called expert consensus statements. They cover the management of people with a type of lung cancer called epidermal growth factor receptor-positive non-small-cell lung cancer (EGFR-positive NSCLC for short). WHY WERE THE RECOMMENDATIONS DEVELOPED?: The ESMO Clinical Practice Guidelines are used by healthcare professionals when treating people with cancer, but they don't necessarily have all the information healthcare professionals need to make decisions for with people with EGFR-positive NSCLC. So, in 2021, 32 healthcare professionals who are experts in treating people with EGFR-positive NSCLC worked together to produce recommendations to fill these gaps about EGFR-positive NSCLC. This was called a consensus-building process and it also included patient advocates. WHAT RECOMMENDATIONS DID THEY MAKE?: The experts discussed four main topics including how people with different stages of EGFR-positive NSCLC are diagnosed and treated, and how clinical studies are done. They reviewed the scientific information that exists on these subjects. They reached an agreement and developed the recommendations that are summarized here.

5.
Future Oncol ; 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36935639

RESUMO

WHAT IS THIS SUMMARY ABOUT?: This is a plain language summary of a guideline on the management of stage 3 non-small-cell lung cancer, also known as NSCLC. This guideline was written by the American Society for Clinical Oncology (ASCO for short) and published in the Journal of Clinical Oncology. WHY WERE THE GUIDELINES DEVELOPED?: The purpose of the ASCO guideline is to provide recommendations to healthcare professionals in the US including oncologists, surgeons, pathologists, radiologists, and nurses on how best to diagnose and treat people with stage 3 NSCLC. HOW WERE THE GUILDEINES DEVELOPED?: The ASCO guideline is based on the latest research and scientific evidence to make certain the recommendations are up to date and based on reliable data and best practice. In 2021, a group of experts were asked by ASCO to form an Expert Panel. The Expert Panel reviewed the results of 127 clinical research studies on NSCLC that were done between 1990 and 2021. They looked at how NSCLC had been diagnosed and treated in these studies, as well as at patients' survival and quality of life. The Expert Panel used these findings and their own expertise to form their recommendations and produce the 2021 ASCO Guideline called 'Management of Stage 3 Non-Small-Cell Lung Cancer: ASCO Guideline'. WHAT INFORMATION DOES THE GUIDELINE CONTAIN?: The guideline aims to answer the following questions: What are the most precise ways to confirm and stage NSCLC in people suspected of having a stage 3 disease? Which patients with stage 3 NSCLC can be treated most successfully with surgery? Which patients who can be treated with surgery could also have an additional therapy before their surgery? Which patients who can be treated with surgery could also have an additional treatment after their surgery? Which treatment and/or management is most suitable for patients who cannot have surgery?

6.
Future Oncol ; 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36935641

RESUMO

WHAT IS THIS SUMMARY ABOUT?: This is a plain language summary of a medical journal article called 'Cancer statistics, 2022'. The data in this summary provides detailed information about lung cancer and less detailed information about other cancers. The researchers from the original study used data gathered from previous years to produce a cancer forecast, predicting the number of new cancer diagnoses and deaths in the United States in 2022. WHAT WERE THE RESULTS?: The review of the data up to 2019 found that compared to previous years: Advanced lung cancer diagnoses had decreased Local stage lung cancer diagnoses had increased Deaths had slowed for lung cancer Deaths continued to reduce for breast cancer, but the rate of this reduction had slowed down Female breast cancer diagnoses were slowly increasing each year Prostate cancer diagnoses stayed similar Local stage prostate cancer diagnoses stayed similar Advanced prostate cancer diagnoses had increased each year The researchers estimated that over 1.9 million new cancer cases would be diagnosed and over half a million cancer deaths would occur in the United States in 2022. This figure includes approximately 350 deaths per day from lung cancer, which was found to be the leading cause of cancer death in the United States. WHAT DO THE RESULTS OF THE STUDY MEAN?: The study found that progress in reducing the number of people being diagnosed with breast and prostate cancer has stalled. Although there were fewer lung cancers diagnosed, this reduction was likely caused by changes in screening and advancements in lung cancer treatments. The American Cancer Society recommended that investing more funds in detecting cancers early as well as developing targeted treatments would help to reduce cancer death rates. This would also help to address the differences in access to cancer care that exist based on racial, social and economic inequalities.

7.
Future Oncol ; 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36935643

RESUMO

WHAT IS THIS SUMMARY ABOUT?: This is a summary of a research study called revised STARS. The STARS study involved people with non-small-cell lung cancer, also known as NSCLC. The cancer was less than 5 cm in size and had not spread to other parts of the body (known as stage 1 cancer). The study compared the effectiveness of surgery versus a type of radiotherapy treatment, called stereotactic ablative radiotherapy (also known as SABR) as a treatment for people with NSCLC. Researchers wanted to find out how likely people were to be alive after treatment or if their cancer had grown or spread to other parts of their body (also known as progressed). WHAT WERE THE RESULTS?: The study found that the long term outcomes were similar between SABR and surgery. People with NSCLC were as likely to be alive 3 years after treatment with SABR compared to surgery. WHAT DO THE RESULTS OF THE STUDY MEAN?: SABR may be an alternative to surgery for people with stage 1 NSCLC which is less than 5 cm in size and has not spread to other parts of the body Clinical Trial Registration: NCT02357992 (ClinicalTrials.gov).

8.
Future Oncol ; 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36935636

RESUMO

WHAT IS THIS SUMMARY ABOUT?: This summary describes the research carried out by the United States Preventive Services Task Force (USPSTF for short) during a review and update of their lung cancer screening recommendations made in 2013. The USPSTF reviewed the results of clinical studies that used a type of scan called low dose computed tomography (LDCT for short). They wanted to see how successful LDCT was at finding lung cancers in people ho hadn't shown any physical signs of lung cancer, but had a history of smoking and were over 50 years of age. WHAT WERE THE RESULTS?: The review found that performing yearly LDCT scans in people who are at high risk of developing lung cancer is beneficial, as it means that some patients will be diagnosed earlier than they would be without this type of screening. People considered to be at high risk of developing lung cancer include: Adults aged 50 to 80 years who have smoked a pack of 20 cigarettes per day for 20 years or two packs per day for 10 years; OR Adults aged 50 to 80 years who currently smoke or have stopped smoking within the last 15 years. WHAT DO THE RESULTS OF THE STUDY MEAN?: The information gained from reviewing the research enabled the USPSTF to update their lung cancer screening recommendations.

9.
Support Care Cancer ; 30(11): 9049-9055, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35948849

RESUMO

INTRODUCTION: To support the care of lung cancer patients, oncologists have needed to stay current on treatment advancements and build relationships with a new group of survivors in an era where lung cancer survivorship has been re-defined. The objectives of the study were to (1) understand the perspectives of advanced lung cancer patients whose tumors have oncogenic alterations about their care experiences with their oncologist(s) and (2) describe the perceptions of advanced lung cancer patients about seeking second opinions and navigating care decisions. METHODS: In this qualitative study, patients with advanced lung cancer (n = 25) on targeted therapies were interviewed to discuss their ongoing experience with their oncologists. We used deductive and inductive qualitative approaches in the coding of the data. We organized the data using the self-determination framework. RESULTS: Patients described both positive and negative aspects of their care as related to autonomy, provider competency, and connectedness. Patients sought second opinions for three primary reasons: expertise, authoritative advice, and access to clinical trial opportunities. When there is disagreement in the treatment plan between the primary oncologist and the specialist, there can be confusion and tension, and patients have to make difficult choices about their path forward. CONCLUSIONS: Patients value interactions that support their autonomy, demonstrate the competency of their providers, and foster connectedness. To ensure that patients receive quality and goal-concordant care, developing decision aids and education materials that help patients negotiate recommendations from two providers is an area that deserves further attention.


Assuntos
Sobreviventes de Câncer , Neoplasias Pulmonares , Neoplasias , Oncologistas , Humanos , Pesquisa Qualitativa , Neoplasias/terapia , Sobreviventes , Neoplasias Pulmonares/terapia
10.
Stem Cells ; 35(12): 2340-2350, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28905448

RESUMO

The transcription factor (TF) yes-associated protein 1 (YAP1) is a major effector of the tumor suppressive Hippo signaling pathway and is also necessary to maintain pluripotency in embryonic stem cells. Elevated levels of YAP1 expression antagonize the tumor suppressive effects of the Hippo pathway that normally represses YAP1 function. High YAP1 expression is observed in several types of human cancers and is particularly prominent in cancer stem cells (CSCs). The stem cell TF Sox2, which marks and maintains CSCs in osteosarcomas (OSs), promotes YAP1 expression by binding to an intronic enhancer element and YAP1 expression is also crucial for the maintainance of OS stem cells. To further understand the regulation of YAP1 expression in OSs, we subjected the YAP1 intronic enhancer to scanning mutagenesis to identify all DNA cis-elements critical for enhancer function. Through this approach, we identified two novel TFs, GA binding protein (GABP) and myeloid zinc finger 1 (MZF1), which are essential for basal YAP1 transcription. These factors are highly expressed in OSs and bind to distinct sites in the YAP1 enhancer. Depletion of either factor leads to drastically reduced YAP1 expression and thus a reversal of stem cell properties. We also found that YAP1 can regulate the expression of Sox2 by binding to two distinct DNA binding sites upstream and downstream of the Sox2 gene. Thus, Sox2 and YAP1 reinforce each others expression to maintain stemness and tumorigenicity in OSs, but the activity of MZF1 and GABP is essential for YAP1 transcription. Stem Cells 2017;35:2340-2350.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Fator de Transcrição de Proteínas de Ligação GA/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Fosfoproteínas/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Linhagem Celular Tumoral , Humanos , Células-Tronco Neoplásicas/metabolismo , Transdução de Sinais/fisiologia , Fatores de Transcrição , Proteínas de Sinalização YAP
12.
Blood ; 123(20): e110-22, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24695852

RESUMO

Macrophages adopt an alternatively activated phenotype (AAMs) when activated by the interleukin-4receptor(R)α. AAMs can be derived either from proliferation of tissue resident macrophages or recruited inflammatory monocytes, but it is not known whether these different sources generate AAMs that are phenotypically and functionally distinct. By transcriptional profiling analysis, we show here that, although both monocyte and tissue-derived AAMs expressed high levels of Arg1, Chi3l3, and Retnla, only monocyte-derived AAMs up-regulated Raldh2 and PD-L2. Monocyte-derived AAMs were also CX3CR1-green fluorescent protein (GFP)(high) and expressed CD206, whereas tissue-derived AAMs were CX3CR1-GFP and CD206 negative. Monocyte-derived AAMs had high levels of aldehyde dehydrogenase activity and promoted the differentiation of FoxP3(+) cells from naïve CD4(+) cells via production of retinoic acid. In contrast, tissue-derived AAMs expressed high levels of uncoupling protein 1. Hence monocyte-derived AAM have properties associated with immune regulation, and the different physiological properties associated with AAM function may depend on the distinct lineage of these cells.


Assuntos
Perfilação da Expressão Gênica , Ativação de Macrófagos , Macrófagos/imunologia , Monócitos/imunologia , Animais , Antígenos CD4/análise , Proliferação de Células , Células Cultivadas , Fatores de Transcrição Forkhead/análise , Expressão Gênica , Canais Iônicos/análise , Canais Iônicos/genética , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Mitocondriais/análise , Proteínas Mitocondriais/genética , Monócitos/citologia , Monócitos/metabolismo , Proteína Desacopladora 1
13.
Prev Chronic Dis ; 11: 130176, 2014 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-24503342

RESUMO

INTRODUCTION: Community-based participatory research (CBPR) has great potential to address cancer disparities, particularly in racially and ethnically diverse and underserved neighborhoods. The objective of this study was to conduct a process evaluation of an innovative academic-community partnership, Queens Library HealthLink, which aimed to reduce cancer disparities through neighborhood groups (Cancer Action Councils) that convened in public libraries in Queens, New York. METHODS: We used a mixed-methods approach to conduct 69 telephone survey interviews and 4 focus groups (15 participants) with Cancer Action Council members. We used 4 performance criteria to inform data collection: action or attention to sustainability, library support for the council, social cohesion and group leadership, and activity level. Focus group transcripts were independently coded and cross-checked for consensus until saturation was achieved. RESULTS: Members reported benefits and barriers to participation. Thirty-three original focus group transcript codes were organized into 8 main themes related to member experiences: 1) library as a needed resource, 2) library as a reputable and nondenominational institution, 3) value of library staff, 4) need for a HealthLink specialist, 5) generation of ideas and coordination of tasks, 6) participation challenges, 7) use of community connections, and 8) collaboration for sustainability. CONCLUSION: In response to the process evaluation, Cancer Action Council members and HealthLink staff incorporated member suggestions to improve council sustainability. The councils merged to increase intercouncil collaboration, and institutional changes were made in funding to sustain a HealthLink specialist beyond the grant period.


Assuntos
Planejamento em Saúde Comunitária/organização & administração , Participação da Comunidade , Promoção da Saúde/métodos , Pesquisa sobre Serviços de Saúde/métodos , Bibliotecas , Neoplasias/prevenção & controle , Comportamentos Relacionados com a Saúde , Humanos , Cidade de Nova Iorque/epidemiologia , Desenvolvimento de Programas
14.
Arch Pathol Lab Med ; 148(7): 757-774, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38625026

RESUMO

CONTEXT.­: Rapid advancements in the understanding and manipulation of tumor-immune interactions have led to the approval of immune therapies for patients with non-small cell lung cancer. Certain immune checkpoint inhibitor therapies require the use of companion diagnostics, but methodologic variability has led to uncertainty around test selection and implementation in practice. OBJECTIVE.­: To develop evidence-based guideline recommendations for the testing of immunotherapy/immunomodulatory biomarkers, including programmed death ligand-1 (PD-L1) and tumor mutation burden (TMB), in patients with lung cancer. DESIGN.­: The College of American Pathologists convened a panel of experts in non-small cell lung cancer and biomarker testing to develop evidence-based recommendations in accordance with the standards for trustworthy clinical practice guidelines established by the National Academy of Medicine. A systematic literature review was conducted to address 8 key questions. Using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach, recommendations were created from the available evidence, certainty of that evidence, and key judgments as defined in the GRADE Evidence to Decision framework. RESULTS.­: Six recommendation statements were developed. CONCLUSIONS.­: This guideline summarizes the current understanding and hurdles associated with the use of PD-L1 expression and TMB testing for immune checkpoint inhibitor therapy selection in patients with advanced non-small cell lung cancer and presents evidence-based recommendations for PD-L1 and TMB testing in the clinical setting.


Assuntos
Antígeno B7-H1 , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas , Inibidores de Checkpoint Imunológico , Neoplasias Pulmonares , Mutação , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/diagnóstico , Antígeno B7-H1/metabolismo , Antígeno B7-H1/antagonistas & inibidores , Inibidores de Checkpoint Imunológico/uso terapêutico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Imunoterapia
15.
Mol Neurobiol ; 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349515

RESUMO

Parkinson's disease (PD) is a neurological disorder that affects dopaminergic neurons. The lack of understanding of the underlying molecular mechanisms of PD pathology makes treating it a challenge. Several pieces of evidence support the protective role of enriched environment (EE) and exercise on dopaminergic neurons. The specific aspect(s) of neuroprotection after exposure to EE have not been identified. Therefore, we have investigated the protective role of EE on dopamine dysregulation and subsequent downregulation of DJ1 protein using in vitro and in vivo models of PD. Our study for the first time demonstrated that DJ1 expression has a direct correlation with dopamine downregulation in PD models and exposure to EE has a significant impact on improving the behavioral changes in PD mice. This research provides evidence that exercise in EE has a positive effect on PD without interfering with the current line of therapy.

16.
Int J Cancer ; 133(1): 43-57, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23280667

RESUMO

Caveolin-1 is an essential component of membrane caveolae. It is an important regulator of cellular processes such as signal transduction and endocytosis. We report here, for the first time, that caveolin-1 is a target of the K-RAS oncogene in colon carcinogenesis. Caveolin-1 is induced in colon cancer cells and in human colon tumor samples, in response to K-RAS activating mutations. An activated K-RAS oncogene transcriptionally induces caveolin-1 expression in human colon cancer cells and this effect is not restricted to the type of activating K-RAS mutation. Inhibition of the P-I3 Kinase-AKT pathway, but not the ERK MAPK pathway, both important K-RAS effectors, leads to a decrease in caveolin-1 expression indicating that the AKT pathway is involved in caveolin-1 expression in response to an activated K-RAS. Increased AKT signaling induces caveolin-1 expression by increasing the activity of the transcription factor, Sp1. Interestingly; caveolin-1 depletion alters K-RAS-dependent signaling by decreasing Grb2-SOS activity. Consistent with these finding, caveolin-1-depleted cells shows decreased migration in vitro. However, caveolin-1 overexpression by itself does not increase migration whereas an activated Src can increase migration in a caveolin-1-dependent manner. This increased migration is highly dependent on the RhoA GTPase, indicating that an activated K-RAS modulates migration in part via caveolin-1 induction, and increasing RhoA activity via phospho-caveolin-1. Our findings indicate that K-RAS regulates both caveolin-1 expression and other factors affecting caveolin-1 functions in colon cancer-derived cell migration.


Assuntos
Caveolina 1/metabolismo , Movimento Celular , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Genes ras , Mutação , Western Blotting , Caveolina 1/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Progressão da Doença , GTP Fosfo-Hidrolases/metabolismo , Regulação Neoplásica da Expressão Gênica , Genes ras/genética , Humanos , Imuno-Histoquímica , Imunoprecipitação , Sistema de Sinalização das MAP Quinases/genética , Plasmídeos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição Sp1/metabolismo , Transfecção , Células Tumorais Cultivadas , Regulação para Cima , Proteína rhoA de Ligação ao GTP/metabolismo
17.
Antimicrob Agents Chemother ; 57(7): 3110-20, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23612193

RESUMO

Long-acting injectable nanoformulated antiretroviral therapy (nanoART) was developed with the explicit goal of improving medicine compliance and for drug targeting of viral tissue reservoirs. Prior nanoART studies completed in humanized virus-infected mice demonstrated sustained antiretroviral responses. However, the pharmacokinetics (PK) and tissue distribution of nanoART were not characterized. To this end, the PK and tissue distribution of nanoformulated atazanavir (ATV) and ritonavir (RTV) injected subcutaneously or intramuscularly in mice and monkeys were evaluated. Fourteen days after injection, ATV and RTV levels were up to 13-, 41-, and 4,500-fold higher than those resulting from native-drug administration in plasma, tissues, and at the site of injection, respectively. At nanoART doses of 10, 50, 100, and 250 mg/kg of body weight, relationships of more- and less-than-proportional increases in plasma and tissue levels with dose increases were demonstrated with ATV and RTV. Multiple-dose regimens showed serum and tissue concentrations up to 270-fold higher than native-drug concentrations throughout 8 weeks of study. Importantly, nanoART was localized in nonlysosomal compartments in tissue macrophages, creating intracellular depot sites. Reflective data were obtained in representative rhesus macaque studies. We conclude that nanoART demonstrates blood and tissue antiretroviral drug levels that are enhanced compared to those of native drugs. The sustained and enhanced PK profile of nanoART is, at least in part, the result of the sustained release of ATV and RTV from tissue macrophases and at the site of injection.


Assuntos
Fármacos Anti-HIV/farmacocinética , Inibidores da Protease de HIV/farmacocinética , Oligopeptídeos/farmacocinética , Piridinas/farmacocinética , Ritonavir/farmacocinética , Animais , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/sangue , Terapia Antirretroviral de Alta Atividade , Sulfato de Atazanavir , Esquema de Medicação , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Inibidores da Protease de HIV/administração & dosagem , Inibidores da Protease de HIV/sangue , Macaca mulatta , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oligopeptídeos/administração & dosagem , Oligopeptídeos/sangue , Piridinas/administração & dosagem , Piridinas/sangue , Ritonavir/administração & dosagem , Ritonavir/sangue , Distribuição Tecidual
18.
Biopolymers ; 100(5): 471-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23897405

RESUMO

Human immunodeficiency virus type-1 (HIV-1), the etiologic agent of acquired immune deficiency syndrome (AIDS), is a global pandemic causing millions of deaths annually. Highly active antiretroviral therapy (HAART) greatly enhances lifespan but eventually causes debilitating side effects, in part, due to their chronic administration required to suppress HIV-1 replication. If treatment is discontinued, viral suppression is lost and dormant replication-competent monocytic cell reservoirs become reactivated, leading to viral recrudescence and progression to AIDS. Therefore, novel strategies to circumvent obstacles to HIV-1 therapy are critically needed. We evaluated the potentially therapeutic effects of cycloviolacin O2 (CyO2) on cell viability (MTT assay), membrane disruption (SYTOX Green uptake), p24 production [enzyme-linked immunosorbent assays (ELISA)], and proviral integration (PCR amplification) in U1 cells; a monocytic cell model of HIV-1 latency and reactivation. We demonstrate, for the first time, that CyO2 (0.5-5.0 µM) kills productively infected cells. Sub-toxic concentrations (<0.5 µM) of CyO2 disrupted plasma membranes in both latently-infected and productively-infected U1 cells and enhanced the antiviral efficacy of nelfinavir, a HIV-1 protease inhibitor (HPI). Interestingly, CyO2 also decreased virus production by activated U1 cells; however, this effect was not due to suppression of integrated provirus in U1 cells. This suggested that, in addition to the known pore-forming ability of cyclotides, a novel mode of antiviral activity may exist for CyO2. Our data indicate that CyO2 may be a promising candidate for the targeting HIV-1 reservoirs in monocytes, and their inclusion in adjuvant therapy approaches may augment the efficacy of HPIs and ultimately facilitate virus elimination.


Assuntos
HIV-1 , Nelfinavir , Antivirais , Linhagem Celular , Infecções por HIV/tratamento farmacológico , Humanos , Monócitos
19.
J Infect Dis ; 206(10): 1577-88, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-22811299

RESUMO

Lack of adherence, inaccessibility to viral reservoirs, long-term drug toxicities, and treatment failures are limitations of current antiretroviral therapy (ART). These limitations lead to increased viral loads, medicine resistance, immunocompromise, and comorbid conditions. To this end, we developed long-acting nanoformulated ART (nanoART) through modifications of existing atazanavir, ritonavir, and efavirenz suspensions in order to establish cell and tissue drug depots to achieve sustained antiretroviral responses. NanoART's abilities to affect immune and antiviral responses, before or following human immunodeficiency virus type 1 infection were tested in nonobese severe combined immune-deficient mice reconstituted with human peripheral blood lymphocytes. Weekly subcutaneous injections of drug nanoformulations at doses from 80 mg/kg to 250 mg/kg, 1 day before and/or 1 and 7 days after viral exposure, elicited drug levels that paralleled the human median effective concentration, and with limited toxicities. NanoART treatment attenuated viral replication and preserved CD4(+) Tcell numbers beyond that seen with orally administered native drugs. These investigations bring us one step closer toward using long-acting antiretrovirals in humans.


Assuntos
Fármacos Anti-HIV/farmacocinética , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Linfócitos/virologia , Nanoestruturas/química , Animais , Fármacos Anti-HIV/sangue , Fármacos Anti-HIV/química , Linfócitos T CD4-Positivos , Formas de Dosagem , Relação Dose-Resposta a Droga , Humanos , Subunidade gama Comum de Receptores de Interleucina/genética , Linfócitos/imunologia , Masculino , Camundongos , Camundongos Knockout , Camundongos SCID , Subpopulações de Linfócitos T
20.
Sci Rep ; 13(1): 3276, 2023 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-36841839

RESUMO

The United Nations projects that one in every six people will be over the age of 65 by the year 2050. With a rapidly aging population, the risk of Alzheimer's disease (AD) becomes a major concern. AD is a multifactorial disease that involves neurodegeneration in the brain with mild dementia and deficits in memory and other cognitive domains. Additionally, it has been established that individuals with Human Immunodeficiency Virus-1 (HIV-1) experience a 5 to 10-year accelerated aging and an increased risk of developing HIV-associated neurocognitive disorders (HAND). Despite a significant amount of clinical evidence pointing towards a potential overlap between neuropathogenic processes in HAND and AD, the underlying epigenetic link between these two diseases is mostly unknown. This study is focused on identifying differentially expressed genes observed in both AD and HAND using linear regression models and a more robust significance analysis of microarray. The results established that the dysregulated type 1 and 2 interferon pathways observed in both AD and HAND contribute to the similar pathologies of these diseases within the brain. The current study identifies the important roles of interferon pathways in AD and HAND, a relationship that may be useful for earlier detection in the future.


Assuntos
Complexo AIDS Demência , Doença de Alzheimer , Infecções por HIV , HIV-1 , Humanos , Idoso , Doença de Alzheimer/metabolismo , Complexo AIDS Demência/patologia , HIV-1/metabolismo , Interferons , Repetições de Tetratricopeptídeos , Transtornos Neurocognitivos/patologia , Infecções por HIV/complicações , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
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