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1.
Cell Signal ; 106: 110634, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36828346

RESUMO

Upregulation of ERBB2 and activating mutations in downstream KRAS/BRAF and PIK3CA are found in several ovarian cancer histotypes. ERBB2 enhances signaling by the ERBB family of EGF receptors, and contains docking positions for proteins that transduce signaling through multiple pathways. We identified the adaptor protein ventricular zone-expressed pleckstrin homology domain-containing protein 1 (VEPH1) as a potential interacting partner of ERBB2 in a screen of proteins co-immunoprecipitated with VEPH1. In this study, we confirm a VEPH1 - ERBB2 interaction by co-immunoprecipitation and biotin proximity labelling and show that VEPH1 interacts with the juxtamembrane-kinase domain of ERBB2. In SKOV3 ovarian cancer cells, which bear a PIK3CA mutation and ERBB2 overexpression, ectopic VEPH1 expression enhanced EGF activation of ERK1/2, and mTORC2 activation of AKT. In contrast, in ES2 ovarian cancer cells, which bear a BRAFV600E mutation with VEPH1 amplification but low ERBB2 expression, loss of VEPH1 expression enabled further activation of ERK1/2 by EGF and enhanced EGF activation of AKT. VEPH1 expression in SKOV3 cells enhanced EGF-induced cell migration consistent with increased Snail2 and decreased E-cadherin levels. In comparison, loss of VEPH1 expression in ES2 cells led to decreased cell motility independent of EGF treatment despite higher levels of N-cadherin and Snail2. Importantly, we found that loss of VEPH1 expression rendered ES2 cells less sensitive to BRAF and MEK inhibition. This study extends the range of adaptor function of VEPH1 to ERBB2, and indicates VEPH1 has differential effects on EGF signaling in ovarian cancer cells that may be influenced by driver gene mutations.


Assuntos
Fator de Crescimento Epidérmico , Neoplasias Ovarianas , Humanos , Feminino , Fator de Crescimento Epidérmico/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Transdução de Sinais , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Receptor ErbB-2/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
2.
J Immunol ; 209(8): 1481-1491, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-36165170

RESUMO

The immunogenicity of a T cell Ag is correlated with the ability of its antigenic epitope to bind HLA and be stably presented to T cells. This presents a challenge for the development of effective cancer immunotherapies, as many self-derived tumor-associated epitopes elicit weak T cell responses, in part due to weak binding affinity to HLA. Traditional methods to increase peptide-HLA binding affinity involve modifying the peptide to reflect HLA allele binding preferences. Using a different approach, we sought to analyze whether the immunogenicity of wild-type peptides could be altered through modification of the HLA binding pocket. After analyzing HLA class I peptide binding pocket alignments, we identified an alanine 81 to leucine (A81L) modification within the F binding pocket of HLA-A*24:02 that was found to heighten the ability of artificial APCs to retain and present HLA-A*24:02-restricted peptides, resulting in increased T cell responses while retaining Ag specificity. This modification led to increased peptide exchange efficiencies for enhanced detection of low-avidity T cells and, when expressed on artificial APCs, resulted in greater expansion of Ag-specific T cells from melanoma-derived tumor-infiltrating lymphocytes. Our study provides an example of how modifications to the HLA binding pocket can enhance wild-type cognate peptide presentation to heighten T cell activation.


Assuntos
Epitopos de Linfócito T , Peptídeos , Alanina , Antígeno HLA-A2 , Antígeno HLA-A24 , Leucina , Linfócitos T
3.
Nat Biotechnol ; 39(8): 958-967, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33649568

RESUMO

Peptide-major histocompatibility complex (pMHC) multimers enable the detection of antigen-specific T cells in studies ranging from vaccine efficacy to cancer immunotherapy. However, this technology is unreliable when applied to pMHC class II for the detection of CD4+ T cells. Here, using a combination of molecular biological and immunological techniques, we cloned sequences encoding human leukocyte antigen (HLA)-DP, HLA-DQ and HLA-DR molecules with enhanced CD4 binding affinity (with a Kd of 8.9 ± 1.1 µM between CD4 and affinity-matured HLA-DP4) and produced affinity-matured class II dimers that stain antigen-specific T cells better than conventional multimers in both in vitro and ex vivo analyses. Using a comprehensive library of dimers for HLA-DP4, which is the most frequent HLA allele in many ancestry groups, we mapped 103 HLA-DP4-restricted epitopes derived from diverse tumor-associated antigens and cloned the cognate T-cell antigen receptor (TCR) genes from in vitro-stimulated CD4+ T cells. The availability of affinity-matured class II dimers across HLA-DP, HLA-DQ and HLA-DR alleles will aid in the investigation of human CD4+ T-cell responses.


Assuntos
Antígenos HLA , Antígenos de Histocompatibilidade Classe II , Coloração e Rotulagem/métodos , Antígenos CD4/química , Antígenos CD4/metabolismo , Linfócitos T CD4-Positivos/química , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Células Cultivadas , Citometria de Fluxo , Antígenos HLA/química , Antígenos HLA/metabolismo , Antígenos de Histocompatibilidade Classe II/química , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Ligação Proteica
4.
Support Care Cancer ; 29(3): 1465-1475, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32691229

RESUMO

PURPOSE: Lung cancer (LC) is a highly prevalent disease with more survivors diagnosed and treated at earlier stages. There is a need to understand psychological and lifestyle behavior needs to design interventions for this population. Furthermore, understanding the needs and role of family caregivers, especially given the risks associated with second-hand smoke, is needed. METHODS: Thirty-one early-stage (stages I or IIA) LC survivors of (52% men) and 22 (50% women) caregivers (N = 53 total) completed surveys after surgery (baseline) and at 3- and 6-month follow-ups. Participants reported on psychological functioning, smoking, and physical activity (PA) as well as intervention preferences. RESULTS: Survivors reported low levels of psychological distress and 3% were current smokers during the study. Approximately 79% were sedentary and not meeting national PA guidelines. Caregivers also reported minimal psychological distress and were sedentary (62% not meeting guidelines), but a larger proportion continued to smoke following the survivor's cancer diagnosis (14%). Both survivors and caregivers expressed interest in home-based PA interventions but differed regarding preferred format for delivery. Most (64%) caregivers preferred a dyadic format, where survivors and caregivers participate in the intervention together. However, most survivors preferred an individual or group format (57%) for intervention delivery. CONCLUSION: Both LC survivors and family caregivers could benefit from PA interventions, and flexible, dyadic interventions could additionally support smoking cessation for family caregivers.


Assuntos
Sobreviventes de Câncer/psicologia , Cuidadores/psicologia , Estilo de Vida , Neoplasias Pulmonares/psicologia , Idoso , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Inquéritos e Questionários
5.
Curr Opin Immunol ; 69: 1-9, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33307272

RESUMO

Immunotherapy has established itself as a stalwart arm in patient care and with precision medicine forms the new paradigm in cancer treatment. T cells are an important group of immune cells capable of potent cancer immune surveillance and immunity. The advent of bioinformatics, particularly more recent advances incorporating algorithms employing machine learning, provide a seemingly limitless ability for T cell analysis and hypothesis generation. Such endeavors have become indispensable to research efforts accelerating and evolving to such an extent that there exists an appreciable gap between knowledge and proof of function and application. Exciting new technologies such as DNA barcoding, cytometry by time-of-flight (CyTOF), and peptide-exchangeable pHLA multimers inclusive of rare and difficult HLA alleles offer high-throughput cell-by-cell analytical capabilities. These outstanding recent contributions to T cell research will help close this gap and potentially bring practical benefit to patients.


Assuntos
Vacinas Anticâncer/imunologia , Imunoterapia Adotiva/métodos , Neoplasias/terapia , Linfócitos T/imunologia , Animais , Código de Barras de DNA Taxonômico , Antígenos HLA/genética , Antígenos HLA/metabolismo , Ensaios de Triagem em Larga Escala , Humanos , Espectrometria de Massas , Neoplasias/imunologia , Medicina de Precisão , Análise de Célula Única
6.
Elife ; 92020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32314731

RESUMO

HLA-restricted T cell responses can induce antitumor effects in cancer patients. Previous human T cell research has largely focused on the few HLA alleles prevalent in a subset of ethnic groups. Here, using a panel of newly developed peptide-exchangeable peptide/HLA multimers and artificial antigen-presenting cells for 25 different class I alleles and greater than 800 peptides, we systematically and comprehensively mapped shared antigenic epitopes recognized by tumor-infiltrating T lymphocytes (TILs) from eight melanoma patients for all their class I alleles. We were able to determine the specificity, on average, of 12.2% of the TILs recognizing a mean of 3.1 shared antigen-derived epitopes across HLA-A, B, and C. Furthermore, we isolated a number of cognate T cell receptor genes with tumor reactivity. Our novel strategy allows for a more complete examination of the immune response and development of novel cancer immunotherapy not limited by HLA allele prevalence or tumor mutation burden.


The immune system is the body's way of defending itself, offering protection against diseases such as cancer. But to remove the cancer cells, the immune system must be able to identify them as different from the rest of the body. All cells break down proteins into shorter fragments, known as peptides, that are displayed on the cell surface by a protein called human leukocyte antigen, HLA for short. Cancer cells display distinctive peptides on their surface as they generate different proteins to those of healthy cells. Immune cells called T cells use these abnormal peptides to identify the cancer so that it can be destroyed. Sometimes T cells can lack the right equipment to detect abnormal peptides, allowing cancer cells to hide from the immune system. However, T cells can be trained through a treatment called immunotherapy, which provides T cells with new tools so that they can spot the peptides displayed by HLA on the previously 'hidden' cancer cells. There are many different forms of HLA, each of which can display different peptides. Current research in immunotherapy commonly targets only a subset of HLA forms, and not all cancer patients have these types. This means that immunotherapy research is only likely to be of most benefit to a limited number of patients. Immunotherapy could be made effective for more people if new cancer peptides that are displayed by the other 'under-represented' forms of HLA were identified. Murata, Nakatsugawa et al. have now used T cells that were taken from tumors in eight patients with melanoma, which is a type of skin cancer. A library of fluorescent HLA-peptides was generated ­ using a new, simplified methodology ­ with 25 forms of HLA that displayed over 800 peptides. T cells were then mixed with the library to identify which HLA-peptides they can target. As a result, Murata, Nakatsugawa et al. found the cancer targets of around 12% of the tumor-infiltrating T cells tested, including those from under-represented forms of HLA. Consequently, these findings could be used to develop new immunotherapies that can treat more patients.


Assuntos
Antígenos de Neoplasias/imunologia , Epitopos de Linfócito T/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Linfócitos do Interstício Tumoral/imunologia , Melanoma/imunologia , Humanos , Receptores de Antígenos de Linfócitos T/imunologia
7.
JAAPA ; 33(3): 17-23, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32039952

RESUMO

Electronic cigarettes are the most common form of nicotine delivery used by youth and young adults, and in 2018, the US Surgeon General declared this to be an epidemic. The developing adolescent brain is vulnerable to nicotine exposure, which can lead to long-lasting cognitive and mood disorders. Screening rates for vaping are low and lack of knowledge by adolescents, clinicians, parents, and caregivers is high. This article reviews the components of vaping, prevalence, adverse reactions, regulation, treatment, and prevention strategies related to vaping in youth and young adults.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina/estatística & dados numéricos , Nicotina/efeitos adversos , Tabagismo/prevenção & controle , Tabagismo/terapia , Vaping/efeitos adversos , Vaping/epidemiologia , Adolescente , Adulto , Fatores Etários , Terapia Cognitivo-Comportamental , Disfunção Cognitiva/etiologia , Feminino , Humanos , Masculino , Transtornos do Humor/etiologia , Prevalência , Dispositivos para o Abandono do Uso de Tabaco , Tabagismo/etiologia , Vaping/prevenção & controle , Adulto Jovem
8.
Int J Hyg Environ Health ; 209(2): 109-21, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16443391

RESUMO

The relationships between blood lead (PbB) and saliva lead (PbSa) concentrations and the determinants of PbB and PbSa status in 970 low-income adults in the city of Detroit, Michigan were explored. Average PbB and PbSa values in the sample population were found to be 2.7+/-0.1 microg/dl and 2.4+/-0.13 microg/l (equivalent to 0.24+/-0.13 microg/dl), respectively, and a weak but statistically significant association was found between the lead levels in the two types of body fluid samples. The average PbB level for men (4.0+/-0.56 microg/dl) was higher than that for women (2.7+/-0.11 microg/dl); other significant predictors of PbB included age, level of education, being employed, income level, the presence of peeling paint on the wall at home and smoking. There was no gender- or age-dependent difference in blood saliva values but statistically significant correlations were found between PbSa and level of education, employment, income level and smoking. Dental caries was severe in this population. Only 0.5% of the participants had no clinical signs of caries, over 80% had cavitated carious lesions (i.e., lesions that had progressed into dentin), and the number of lost teeth and carious lesions averaged 3.4 and 30, respectively. Weak but significant associations were found between PbB as well as PbSa and measures of dental caries in the study population. The positive associations are believed to be a reflection of the fact that the risk factors for dental caries, especially in low-income populations of the US, overlap extensively with those of lead poisoning and may not have a causal significance.


Assuntos
Monitoramento Ambiental/métodos , Chumbo/análise , Saliva/química , Adolescente , Adulto , Biomarcadores/sangue , Criança , Cárie Dentária/epidemiologia , Exposição Ambiental/análise , Monitoramento Epidemiológico , Feminino , Humanos , Chumbo/sangue , Masculino , Michigan , Pessoa de Meia-Idade , Pobreza , População Urbana
9.
J Periodontol ; 67 Suppl 10S: 1085-1093, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29539790

RESUMO

This study tested the hypothesis that severe periodontitis in persons with non-insulin-dependent diabetes mellitus (NIDDM) increases the risk of poor glycemic control. Data from the longitudinal study of residents of the Gila River Indian Community were analyzed for dentate subjects aged 18 to 67, comprising all those: 1) diagnosed at baseline with NIDDM (at least 200 mg/dL plasma glucose after a 2-hour oral glucose tolerance test); 2) with baseline glycosylated hemoglobin (HbA1 ) less than 9%; and 3) who remained dentate during the 2-year follow-up period. Medical and dental examinations were conducted at 2-year intervals. Severe periodontitis was specified two ways for separate analyses: 1) as baseline periodontal attachment loss of 6 mm or more on at least one index tooth; and 2) baseline radiographic bone loss of 50% or more on at least one tooth. Clinical data for loss of periodontal attachment were available for 80 subjects who had at least one follow-up examination, 9 of whom had two follow-up examinations at 2-year intervals after baseline. Radiographic bone loss data were available for 88 subjects who had at least one follow-up examination, 17 of whom had two follow-up examinations. Poor glycemic control was specified as the presence of HbA1 of 9% or more at follow-up. To increase the sample size, observations from baseline to second examination and from second to third examinations were combined. To control for non-independence of observations, generalized estimating equations (GEE) were used for regression modeling. Severe periodontitis at baseline was associated with increased risk of poor glycemic control at follow-up. Other statistically significant covariates in the GEE models were: 1) baseline age; 2) level of glycemic control at baseline; 3) having more severe NIDDM at baseline; 4) duration of NIDDM; and 5) smoking at baseline. These results support considering severe periodontitis as a risk factor for poor glycemic control and suggest that physicians treating patients with NIDDM should be alert to the signs of severe periodontitis in managing NIDDM. J Periodontol 1996;67:1085-1093.

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