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1.
Cancer Immunol Immunother ; 72(7): 2075-2086, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36806983

RESUMO

Multiple targeted therapeutics have been approved by the FDA for mUC, including immune checkpoint inhibitors (ICIs) and more recently targeted agents for both FGFR and Nectin-4. FGFR3-aberrant and Nectin-4 expressing cells have been associated with an immunosuppressed phenotype. Given that less than half of all patients respond to these agents as monotherapies and less than 20% are eligible to receive salvage therapy, effective personalized treatment plans are critical. Typical biomarkers for ICIs such as PD-L1 and TMB have not been definitive in mUC, yet a biomarker-driven optimization of first-line therapy and subsequent sequencing have the potential to achieve higher and more durable response rates. The IO score is a 27-gene tumor immune microenvironment (TIME) classifier that has been associated with the clinical benefits of ICIs in multiple cancer types, including mUC. This study demonstrates that the IO score was associated with both progression-free survival (PFS) and overall survival (OS) in a real-world cohort of mUC patients treated with ICIs. Furthermore, the IO score was independent of and provided information incremental to TMB. Interestingly, the IO score predicted benefit in patients with high FGFR expression, despite conflicting data regarding response rates among the FGFR aberrant population. Taken together, these results demonstrate that the IO score assessment of the TIME is associated with a clinical benefit from ICI therapy and that this novel biomarker may inform therapeutic sequencing decisions in mUC, potentially improving outcomes for this notoriously difficult-to-treat disease.


Assuntos
Antineoplásicos Imunológicos , Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células de Transição , Neoplasias Pulmonares , Neoplasias da Bexiga Urinária , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Receptor de Morte Celular Programada 1/uso terapêutico , Nectinas , Neoplasias da Bexiga Urinária/tratamento farmacológico , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1 , Microambiente Tumoral
2.
Clin Lung Cancer ; 24(2): 137-144, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36564297

RESUMO

BACKGROUND: Immune checkpoint inhibitors (ICI) are standard of care in advanced non-small cell lung cancer (NSCLC). However, not all patients benefit, even among PD-L1 tumor proportional score (TPS) ≥50%, indicating an unmet need for additional biomarkers such as those assessing the tumor immune microenvironment (TIME). DetermaIO is a 27-gene assay that classifies TIME and has previously demonstrated association with ICI response. METHODS: FFPE samples were selected from BC Cancer and West Clinic Cancer Center patients with performance status (PS) ≤2 who received at least 2 cycles of ICI monotherapy in the first (1L) or second line (2L). IO scores were generated and analyzed for association with PFS and OS. RESULTS: In the entire cohort (N=147), IO score was significantly associated with OS (HR=0.68, 95%CI 0.47-0.99, P = .042) and PFS (HR=0.62, 95%CI 0.43-0.88, P = .0069). In 1L treated patients (PD-L1≥50%, N=78), IO score was significantly associated with PFS (HR=0.55, 95%CI 0.32-0.94, P = .028). In exploratory analyses, IO score was associated with benefit in 1L PS2 patients for OS (HR = 0.26, 95%CI 0.091-0.74, P = .012) and PFS (HR = 0.27, 95%CI 0.098-0.72, P = .0095) which was confirmed in PFS subgroup analysis in the independent West Cancer Center study (N=13 HR=0.14, 95%CI 0.027-0.76, P = .023). CONCLUSION: These data confirm the association of DetermaIO with ICI clinical benefit in NSCLC, and expand on previous studies by demonstrating that first line treated PD-L1≥50% patients can further be stratified by IO score to identify efficacy. Exploratory analysis suggested that the IO score identifies benefit in patients with poor PS.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Antígeno B7-H1 , Estudos Retrospectivos , Imunoterapia , Microambiente Tumoral
3.
J Transl Med ; 20(1): 370, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35974414

RESUMO

BACKGROUND: The IO Score is a 27-gene immuno-oncology (IO) classifier that has previously predicted benefit to immune checkpoint inhibitor (ICI) therapy in triple negative breast cancer (TNBC) and non-small cell lung cancer (NSCLC). It generates both a continuous score and a binary result using a defined threshold that is conserved between breast and lung. Herein, we aimed to evaluate the IO Score's binary threshold in ICI-naïve TCGA bladder cancer patients (TCGA-BLCA) and assess its clinical utility in metastatic urothelial cancer (mUC) using the IMvigor210 clinical trial treated with the ICI, atezolizumab. METHODS: We identified a list of tumor immune microenvironment (TIME) related genes expressed across the TCGA breast, lung squamous and lung adenocarcinoma cohorts (TCGA-BRCA, TCGA-LUSQ, and TCGA-LUAD, 939 genes total) and then examined the expression of these 939 genes in TCGA-BLCA, to identify patients as having high inflammatory gene expression. Using this as a test of classification, we assessed the previously established threshold of IO Score. We then evaluated the IO Score with this threshold in the IMvigor210 cohort for its association with overall survival (OS). RESULTS: In TCGA-BLCA, IO Score positive patients had a strong concordance with high inflammatory gene expression (p < 0.0001). Given this concordance, we applied the IO Score to the ICI treated IMvigor210 patients. IO Score positive patients (40%) had a significant Cox proportional hazard ratio (HR) of 0.59 (95% CI 0.45-0.78 p < 0.001) for OS and improved median OS (15.6 versus 7.5 months) compared to IO Score negative patients. The IO Score remained significant in bivariate models combined with all other clinical factors and biomarkers, including PD-L1 protein expression and tumor mutational burden. CONCLUSION: The IMvigor210 results demonstrate the potential for the IO Score as a clinically useful biomarker in mUC. As this is the third tumor type assessed using the same algorithm and threshold, the IO Score may be a promising candidate as a tissue agnostic marker of ICI clinical benefit. The concordance between IO Score and inflammatory gene expression suggests that the classifier is capturing common features of the TIME across cancer types.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antígeno B7-H1/genética , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Ensaios Clínicos como Assunto , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/patologia , Microambiente Tumoral
4.
Front Cell Infect Microbiol ; 12: 882498, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35694541

RESUMO

Tight junctions (TJs) are essential components of intestinal barrier integrity and protect the epithelium against passive paracellular flux and microbial translocation. Dysfunctional TJ leads to leaky gut, a condition associated with diseases including inflammatory bowel disease (IBD). Sulfate-Reducing Bacteria (SRB) are minor residents of the gut. An increased number of Desulfovibrio, the most predominant SRB, is observed in IBD and other diseases associated with leaky gut. However, it is not known whether Desulfovibrio contributes to leaky gut. We tested the hypothesis that Desulfovibrio vulgaris (DSV) may induce intestinal permeability in vitro. Snail, a transcription factor, disrupts barrier function by affecting TJ proteins such as occludin. Intestinal alkaline phosphatase (IAP), a host defense protein, protects epithelial barrier integrity. We tested whether DSV induced permeability in polarized Caco-2 cells via snail and if this effect was inhibited by IAP. Barrier integrity was assessed by measuring transepithelial electric resistance (TEER) and by 4kDa FITC-Dextran flux to determine paracellular permeability. We found that DSV reduced TEER, increased FITC-flux, upregulated snail protein expression, caused nuclear translocation of snail, and disrupted occludin staining at the junctions. DSV-induced permeability effects were inhibited in cells knocked down for snail. Pre-treatment of cells with IAP inhibited DSV-induced FITC flux and snail expression and DSV-mediated disruption of occludin staining. These data show that DSV, a resident commensal bacterium, can contribute to leaky gut and that snail may serve as a novel therapeutic target to mitigate DSV-induced effects. Taken together, our study suggests a novel underlying mechanism of association of Desulfovibrio bloom with diseases with increased intestinal permeability. Our study also underscores IAP as a novel therapeutic intervention for correcting SRB-induced leaky gut via inhibition of snail.


Assuntos
Fosfatase Alcalina/metabolismo , Desulfovibrio , Doenças Inflamatórias Intestinais , Bactérias/metabolismo , Células CACO-2 , Fluoresceína-5-Isotiocianato/metabolismo , Fluoresceína-5-Isotiocianato/farmacologia , Proteínas Ligadas por GPI/metabolismo , Humanos , Doenças Inflamatórias Intestinais/metabolismo , Mucosa Intestinal/metabolismo , Ocludina/metabolismo , Permeabilidade , Sulfatos/metabolismo , Junções Íntimas/metabolismo
5.
Anaerobe ; 75: 102582, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35533828

RESUMO

Desulfovibrio spp. is a commensal sulfate reducing bacterium that is present in small numbers in the gastrointestinal tract. Increased concentrations of Desulfovibrio spp. (blooms) have been reported in patients with inflammatory bowel disease and irritable bowel syndrome. Since stress has been reported to exacerbate symptoms of these chronic diseases, this study examined whether the stress catecholamine norepinephrine (NE) promotes Desulfovibrio growth. Norepinephrine-stimulated growth has been reported in other bacterial taxa, and this effect may depend on the availability of the micronutrient iron. OBJECTIVES: This study tested whether norepinephrine exposure affects the in vitro growth of Desulfovibrio vulgaris in an iron dependent manner. METHODS: DSV was incubated in a growth medium with and without 1 µm of norepinephrine. An additional growth assay added the iron chelator deferoxamine in NE exposed DSV. Iron regulatory genes were assessed with and without the treatment of NE and Deferoxamine. RESULTS: We found that norepinephrine significantly increased growth of D. vulgaris. Norepinephrine also increased bacterial production of hydrogen sulfide. Additionally, norepinephrine significantly increased bacterial expression in three of the four tested iron regulatory genes. The iron chelator deferoxamine inhibited growth of D. vulgaris in a dose-dependent manner and reversed the effect of norepinephrine on proliferation of D. vulgaris and on bacterial expression of iron regulatory genes. CONCLUSION: The data presented in this work suggests that promotion of D. vulgaris growth by norepinephrine is iron dependent.


Assuntos
Desulfovibrio vulgaris , Desulfovibrio , Desferroxamina/metabolismo , Desferroxamina/farmacologia , Desulfovibrio/metabolismo , Desulfovibrio vulgaris/genética , Humanos , Ferro/metabolismo , Quelantes de Ferro/metabolismo , Quelantes de Ferro/farmacologia , Norepinefrina/metabolismo , Norepinefrina/farmacologia
6.
BMC Cancer ; 22(1): 407, 2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35421940

RESUMO

BACKGROUND: Immune checkpoint inhibitor (ICI) therapies represent a major advance in treating a variety of advanced-stage malignancies. Nevertheless, only a subset of patients benefit, even when selected based on approved biomarkers such as PD-L1 and tumor mutational burden. New biomarkers are needed to maximize the therapeutic ratio of these therapies. METHODS: In this retrospective cohort, we assessed a 27-gene RT-qPCR immuno-oncology (IO) gene expression assay of the tumor immune microenvironment and determined its association with the efficacy of ICI therapy in 67 advanced-stage NSCLC patients. The 27-gene IO test score (IO score), programmed cell death ligand 1 immunohistochemistry tumor proportion score (PD-L1 TPS), and tumor mutational burden (TMB) were analyzed as continuous variables for response and as binary variables for one-year progression free survival. The threshold for the IO score was prospectively set based upon a previously described training cohort. Prognostic implications of the IO score were evaluated in a separate cohort of 104 advanced-stage NSCLC patients from The Cancer Genome Atlas (TCGA) who received non-ICI therapy. RESULTS: The IO score was significantly different between responders or non-responders (p = 0.007) and associated with progression-free survival (p = 0.001). Bivariate analysis established that the IO score was independent of PD-L1 TPS and TMB in identifying patients benefiting from ICI therapy. In a separate cohort of late-stage NSCLC patients from TCGA, the IO score was not prognostic of outcome from non-ICI-treated patients. CONCLUSIONS: This study is the first application of this 27-gene IO RT-qPCR assay in a clinical cohort with outcome data. IO scores were significantly associated with response to ICI therapy and prolonged progression-free survival. Together, these data suggest the IO score should be further studied to define its role in informing clinical decision-making for ICI treatment in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Microambiente Tumoral
7.
Front Cell Infect Microbiol ; 11: 695299, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34336718

RESUMO

Sulfate Reducing Bacteria (SRB), usually rare residents of the gut, are often found in increased numbers (called a SRB bloom) in inflammatory conditions such as Inflammatory Bowel Disease (IBD), pouchitis, and periodontitis. However, the underlying mechanisms of this association remain largely unknown. Notch signaling, a conserved cell-cell communication pathway, is usually involved in tissue development and differentiation. Dysregulated Notch signaling is observed in inflammatory conditions such as IBD. Lipolysaccharide and pathogens also activate Notch pathway in macrophages. In this study, we tested whether Desulfovibrio, the most dominant SRB genus in the gut, may activate Notch signaling. RAW 264.7 macrophages were infected with Desulfovibrio vulgaris (DSV) and analyzed for the expression of Notch signaling pathway-related proteins. We found that DSV induced protein expression of Notch1 receptor, Notch intracellular domain (NICD) and p21, a downstream Notch target, in a dose-and time-dependent manner. DSV also induced the expression of pro-IL1ß, a precursor of IL-1ß, and SOCS3, a regulator of cytokine signaling. The gamma secretase inhibitor DAPT or Notch siRNA dampened DSV-induced Notch-related protein expression as well the expression of pro-IL1ß and SOCS3. Induction of Notch-related proteins by DSV was not affected by TLR4 -IN -C34(C34), a TLR4 receptor antagonist. Additionally, cell-free supernatant of DSV-infected macrophages induced NICD expression in uninfected macrophages. DSV also activated Notch pathway in the human epithelial cell line HCT116 and in mouse small intestine. Thus, our study uncovers a novel mechanism by which SRB interact with host cells by activating Notch signaling pathway. Our study lays a framework for examining whether the Notch pathway induced by SRB contributes to inflammation in conditions associated with SRB bloom and whether it can be targeted as a therapeutic approach to treat these conditions.


Assuntos
Desulfovibrio , Receptor Notch1 , Transdução de Sinais , Animais , Bactérias , Camundongos , Células RAW 264.7 , Sulfatos
8.
Viruses ; 13(2)2021 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-33672780

RESUMO

For decades, bacteriophage purification has followed structured protocols focused on generating high concentrations of phage in manageable volumes. As research moves toward understanding complex phage populations, purification needs have shifted to maximize the amount of phage while maintaining diversity and activity. The effects of standard phage purification procedures such as polyethylene glycol (PEG) precipitation and cesium chloride (CsCl) density gradients on both diversity and activity of a phage population are not known. We have examined the effects of PEG precipitation and CsCl density gradients on a number of known phage (M13, T4, and ΦX 174) of varying structure and size, individually and as mixed sample. Measurement of phage numbers and activity throughout the purification process was performed. We demonstrate that these methods, used routinely to generate "pure" phage samples, are in fact detrimental to retention of phage number and activity; even more so in mixed phage samples. As such, minimal amounts of processing are recommended to introduce less bias and maintain more of a phage population.


Assuntos
Bacteriófagos/fisiologia , Ultracentrifugação/métodos , Bacteriófagos/química , Bacteriófagos/isolamento & purificação , Césio/química , Cloretos/química
9.
Gut Microbes ; 13(1): 1-13, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33382363

RESUMO

Infection with Helicobacter pylori is the single greatest risk factor for developing gastric adenocarcinoma. In prospective, population-based studies, seropositivity to the uncharacterized H. pylori proteins Hp0305 and Hp1564 was significantly associated with cancer risk in East Asia. However, the mechanism underlying this observation has not been elucidated. Here, we show that Hp0305 and Hp1564 act in concert with previously ascribed H. pylori virulence mechanisms to orchestrate cellular alterations that promote gastric carcinogenesis. In samples from 546 patients exhibiting premalignant gastric lesions, seropositivity to Hp0305 and Hp1564 was significantly associated with increased gastric atrophy across all stomach conditions. In vitro, depletion of Hp0305 and Hp1564 significantly reduced levels of gastric cell-associated bacteria and markedly impaired the ability of H. pylori to stimulate pro-inflammatory cytokine production. Remarkably, our studies revealed that Hp1564 is required for translocation of the oncoprotein CagA into gastric epithelial cells. Our data provide experimental insight into the molecular mechanisms governing novel H. pylori pathogenicity factors that are strongly associated with gastric disease and highlight the potential of Hp0305 and Hp1564 as robust molecular tools that can improve identification of individuals that are highly susceptible to gastric cancer. We demonstrate that Hp0305 and Hp1564 augment H. pylori-mediated inflammation and gastric cancer risk by promoting key bacteria-gastric cell interactions that facilitate delivery of oncogenic microbial cargo to target cells. Thus, therapeutically targeting microbial interactions driven by Hp0305/Hp1564 may enable focused H. pylori eradication strategies to prevent development of gastric malignancies in high-risk populations.


Assuntos
Antígenos de Bactérias/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Bactérias/metabolismo , Helicobacter pylori/patogenicidade , Lesões Pré-Cancerosas/microbiologia , Neoplasias Gástricas/microbiologia , Anticorpos Antibacterianos/sangue , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Linhagem Celular , Citocinas/metabolismo , Feminino , Mucosa Gástrica/metabolismo , Regulação Bacteriana da Expressão Gênica , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Pepsinogênio A/sangue , Pepsinogênio C/sangue , Lesões Pré-Cancerosas/sangue , Neoplasias Gástricas/sangue
10.
Cancer Epidemiol Biomarkers Prev ; 29(10): 2084-2092, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32856604

RESUMO

BACKGROUND: Prevalence of Helicobacter pylori (H. pylori) infection, the main risk factor for gastric cancer, has been decreasing in the United States; however, there remains a substantial racial disparity. Moreover, the time-trends for prevalence of CagA-positive H. pylori infection, the most virulent form, are unknown in the U.S. POPULATION: We sought to assess prevalence of CagA-positive H. pylori infection over time by race in the United States. METHODS: We utilized multiplex serology to quantify antibody responses to H. pylori antigens in 4,476 participants across five cohorts that sampled adults from 1985 to 2009. Using log-binomial regression models, we calculated prevalence ratios and 95% confidence intervals for the association between H. pylori-CagA sero-prevalence and birth year by race. RESULTS: African Americans were three times more likely to be H. pylori-CagA sero-positive than Whites. After adjustment, H. pylori-CagA sero-prevalence was lower with increasing birth year among Whites (P trend = 0.001), but remained stable for African Americans. When stratified by sex and education separately, the decline in H. pylori-CagA sero-positivity among Whites remained only for females (P trend < 0.001) and was independent of educational attainment. Among African Americans, there was no difference by sex; furthermore, sero-prevalence increased with increasing birth year among those with a high school education or less (P = 0.006). CONCLUSIONS: Among individuals in the United States born from the 1920s to 1960s, H. pylori-CagA sero-prevalence has declined among Whites, but not among African Americans. IMPACT: Our findings suggest a widening racial disparity in the prevalence of the most virulent form of H. pylori, the main cause of gastric cancer.


Assuntos
Helicobacter pylori/patogenicidade , Fatores Raciais/estatística & dados numéricos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Estados Unidos
11.
J Pediatric Infect Dis Soc ; 9(4): 486-489, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31362308

RESUMO

We present here the first published use of letermovir for the treatment of resistant cytomegalovirus (CMV) in a pediatric patient. A 14-year-old girl underwent a double unrelated umbilical cord blood transplantation to treat her sickle cell disease (hemoglobin SS) and developed ganciclovir-resistant CMV DNAemia with end-organ involvement that was treated successfully with a combination of foscarnet and letermovir. After she was transitioned to letermovir monotherapy for secondary prophylaxis, she developed recurrent DNAemia with laboratory-confirmed ganciclovir, foscarnet, and letermovir resistance.


Assuntos
Acetatos/uso terapêutico , Antivirais/uso terapêutico , Infecções por Citomegalovirus/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas , Quinazolinas/uso terapêutico , Terapia de Salvação , Adolescente , Farmacorresistência Viral , Feminino , Humanos , Hospedeiro Imunocomprometido
12.
Helicobacter ; 25(1): e12671, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31746104

RESUMO

PURPOSE: To feasibly analyze associations of Helicobacter pylori (H. pylori) with disease in large cohort studies, assays are needed to assess H. pylori prevalence in existing biospecimens. However, serology has traditionally been unable to distinguish active from past infection. We sought to determine the sensitivity of seropositivity to H. pylori proteins to detect active infection. METHODS: We measured antibody responses to 13 H. pylori proteins using multiplex serology in serum samples of a training (n = 78) and validation set (n = 49) collected concurrently from patients undergoing urea breath test (UBT). To determine sensitivity of seropositivity to H. pylori proteins for active infection, a cutoff was applied to achieve 90% specificity. Antibody levels were retested in a subset of participants (n = 16) 6 months after baseline. RESULTS: With a specificity of 91%, seropositivity to H. pylori proteins VacA, GroEl, HcpC, and HP1564 ascertained active infection from 100% to 75% sensitivity. Positivity to a combination of these proteins (≥2 out of the 4) resulted in specificity of 90% and sensitivity of 100%. The validation set replicated results from the training set. Among those participants with successful H. pylori eradication after baseline, antibody levels decreased significantly for VacA, HcpC, and HP1564 when assessed 6 months later. CONCLUSION: Utilizing the cutoffs for seropositivity established through comparison with UBT, seropositivity to ≥2 of the H. pylori proteins VacA, GroEl, HcpC, and HP1564 determines active H. pylori infection at high specificity and sensitivity and may approximate the prevalence of active H. pylori infection in large cohorts.


Assuntos
Infecções por Helicobacter/sangue , Helicobacter pylori/imunologia , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Estudos de Coortes , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/etnologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Sudeste dos Estados Unidos/etnologia
13.
Cancer Prev Res (Phila) ; 12(10): 667-674, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31350279

RESUMO

Smoking is an established risk factor for gastric cancer development. In this study, we aimed to assess prospectively the association of smoking with gastric cancer risk in 1,446 non-cardia gastric cancer cases and 1,796 controls from China, Japan, and Korea with consideration of Helicobacter pylori infection as a potential effect modifier. Applying logistic regression models stratified by study and adjusted for age and sex we found that current, but not former, smoking was significantly associated with gastric cancer risk [OR = 1.33; 95% confidence interval (CI), 1.07-1.65]. However, the association was significant only in H. pylori sero-positive individuals determined by 3 different sero-markers: overall sero-positivity, sero-positivity to the onco-protein CagA, and sero-positivity to the gastric cancer associated sero-marker HP0305 and HP1564. Specifically, a significant interaction was found when stratifying by HP0305/HP1564 (P interaction = 0.01) with a 46% increased risk of gastric cancer among HP0305/HP1564 sero-positive current smokers (95% CI, 1.10-1.93) as opposed to no increased gastric cancer risk among HP0305/HP1564 sero-negative current smokers (OR = 0.93; 95% CI, 0.65-1.33). We confirmed that current smoking is associated with an increased gastric cancer risk, however, only among individuals that are simultaneously sero-positive for the leading causal factor for gastric cancer, H. pylori.


Assuntos
Infecções por Helicobacter/epidemiologia , Fumar/epidemiologia , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/etiologia , Adenocarcinoma/epidemiologia , Adenocarcinoma/etiologia , Idoso , Estudos de Casos e Controles , China/epidemiologia , Estudos de Coortes , Modificador do Efeito Epidemiológico , Feminino , Infecções por Helicobacter/sangue , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/imunologia , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Fatores de Risco , Estudos Soroepidemiológicos , Testes Sorológicos/estatística & dados numéricos , Fumar/efeitos adversos , Fumar Tabaco/efeitos adversos , Fumar Tabaco/epidemiologia
14.
mBio ; 10(3)2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138752

RESUMO

Helicobacter pylori is the strongest risk factor for gastric adenocarcinoma; however, most infected individuals never develop this malignancy. Strain-specific microbial factors, such as the oncoprotein CagA, as well as environmental conditions, such as iron deficiency, augment cancer risk. Importantly, dysbiosis of the gastric microbiota is also associated with gastric cancer. To investigate the combinatorial effects of these determinants in an in vivo model of gastric cancer, Mongolian gerbils were infected with the carcinogenic cag+H. pylori strain 7.13 or a 7.13 cagA isogenic mutant, and microbial DNA extracted from gastric tissue was analyzed by 16S rRNA sequencing. Infection with H. pylori significantly increased gastric inflammation and injury, decreased α-diversity, and altered microbial community structure in a cagA-dependent manner. The effect of iron deficiency on gastric microbial communities was also investigated within the context of infection. H. pylori-induced injury was augmented under conditions of iron deficiency, but despite differences in gastric pathology, there were no significant differences in α- or ß-diversity, phyla, or operational taxonomic unit (OTU) abundance among infected gerbils maintained on iron-replete or iron-depleted diets. However, when microbial composition was stratified based solely on the severity of histologic injury, significant differences in α- and ß-diversity were present among gerbils harboring premalignant or malignant lesions compared to gerbils with gastritis alone. This study demonstrates that H. pylori decreases gastric microbial diversity and community structure in a cagA-dependent manner and that as carcinogenesis progresses, there are corresponding alterations in community structure that parallel the severity of disease.IMPORTANCE Microbial communities are essential for the maintenance of human health, and when these communities are altered, hosts can become susceptible to inflammation and disease. Dysbiosis contributes to gastrointestinal cancers, and specific bacterial species are associated with this phenotype. This study uses a robust and reproducible animal model to demonstrate that H. pylori infection induces gastric dysbiosis in a cagA-dependent manner and further that dysbiosis and altered microbial community structure parallel the severity of H. pylori-induced gastric injury. Ultimately, such models of H. pylori infection and cancer that can effectively evaluate multiple determinants simultaneously may yield effective strategies for manipulating the gastric microbiota to prevent the development of gastric cancer.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Disbiose/microbiologia , Mucosa Gástrica/microbiologia , Helicobacter pylori/patogenicidade , Proteínas Oncogênicas/genética , Animais , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Modelos Animais de Doenças , Mucosa Gástrica/patologia , Gerbillinae/microbiologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Masculino , Proteínas Oncogênicas/metabolismo , Fenótipo , RNA Ribossômico 16S/genética , Neoplasias Gástricas/microbiologia
15.
Gastroenterology ; 156(8): 2356, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31039340
16.
Gastroenterology ; 156(1): 175-186.e2, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30296434

RESUMO

BACKGROUND & AIMS: Previous studies reported an association of the bacteria Helicobacter pylori, the primary cause of gastric cancer, and risk of colorectal cancer (CRC). However, these findings have been inconsistent, appear to vary with population characteristics, and may be specific for virulence factor VacA. To more thoroughly evaluate the potential association of H pylori antibodies with CRC risk, we assembled a large consortium of cohorts representing diverse populations in the United States. METHODS: We used H pylori multiplex serologic assays to analyze serum samples from 4063 incident cases of CRC, collected before diagnosis, and 4063 matched individuals without CRC (controls) from 10 prospective cohorts for antibody responses to 13 H pylori proteins, including virulence factors VacA and CagA. The association of seropositivity to H pylori proteins, as well as protein-specific antibody level, with odds of CRC was determined by conditional logistic regression. RESULTS: Overall, 40% of controls and 41% of cases were H pylori-seropositive (odds ratio [OR], 1.09; 95% CI, 0.99-1.20). H pylori VacA-specific seropositivity was associated with an 11% increased odds of CRC (OR, 1.11; 95% CI, 1.01-1.22), and this association was particularly strong among African Americans (OR, 1.45; 95% CI, 1.08-1.95). Additionally, odds of CRC increased with level of VacA antibody in the overall cohort (P = .008) and specifically among African Americans (P = .007). CONCLUSIONS: In an analysis of a large consortium of cohorts representing diverse populations, we found serologic responses to H pylori VacA to associate with increased risk of CRC risk, particularly for African Americans. Future studies should seek to understand whether this marker is related to virulent H pylori strains carried in these populations.


Assuntos
Anticorpos Antibacterianos/imunologia , Proteínas de Bactérias/imunologia , Neoplasias Colorretais/microbiologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antibacterianos/sangue , Biomarcadores/sangue , Estudos de Casos e Controles , Neoplasias Colorretais/sangue , Neoplasias Colorretais/epidemiologia , Feminino , Infecções por Helicobacter/sangue , Infecções por Helicobacter/epidemiologia , Helicobacter pylori/patogenicidade , Interações Hospedeiro-Patógeno , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Estudos Soroepidemiológicos , Estados Unidos/epidemiologia , Virulência , Adulto Jovem
17.
J Med Virol ; 91(3): 450-456, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30307626

RESUMO

STATEMENT OF THE PROBLEM: Human papillomavirus (HPV) infection is known to contribute to cervical carcinogenesis, yet other cofactors that may contribute to oncogenesis are poorly understood. Herein, we examine whether the Epstein-Barr virus (EBV) and human cytomegalovirus (CMV), two oncomodulatory viruses, are associated with HPV-mediated cervical neoplastic progression. METHODS: Sixty patient cervical brush samples from a study of North Carolina women were obtained. HPV RNA positivity was determined by Aptima testing (Hologic Corporation, Marlborough, MA). The level of viral transcripts for EBV and CMV was quantified (reverse transcription polymerase chain reaction analysis), and the coinfection status with HPV was then compared with the patient's cervical cytology grade. RESULTS: Over one-third (38.3%) of the study population was CMV positive, whereas 43.3% was EBV positive. When sample data were stratified by the cytology grade, 36.5% (19/52) of normal patients, 75% (3/4) of low-grade squamous intraepithelial lesions (LSIL), and 100% (4/4) of patients with high-grade SIL (HSIL) were EBV positive. Conversely, 35.2% (18/52) of normal patients, 25% (1/4) of patients with LSIL, and 50% (2/4) of patients with HSIL were CMV positive. When examining only HPV positive-associated HSIL, 100% (4/4) were positive for both HPV and EBV detection. This suggests that co-viral detection with HPV and EBV is associated with more advanced HSIL cervical lesions, while CMV displayed no clear association with a higher grade of cervical cytology. CONCLUSIONS: Co-viral detection with EBV may increase the oncogenicity and/or serve as a viral marker of progression to HPV-associated high-grade cervical dysplasia.


Assuntos
Colo do Útero/virologia , Coinfecção/virologia , Infecções por Vírus Epstein-Barr/epidemiologia , Infecções por Papillomavirus/epidemiologia , Neoplasias do Colo do Útero/virologia , Adulto , Idoso , Coinfecção/epidemiologia , Citomegalovirus , DNA Viral/genética , Progressão da Doença , Infecções por Vírus Epstein-Barr/complicações , Feminino , Herpesvirus Humano 4 , Humanos , Pessoa de Meia-Idade , North Carolina/epidemiologia , Papillomaviridae , Infecções por Papillomavirus/complicações , Neoplasias do Colo do Útero/epidemiologia , Esfregaço Vaginal , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/virologia
18.
Dig Dis Sci ; 63(10): 2765-2772, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29948559

RESUMO

BACKGROUND: Epstein-Barr virus (EBV)-positive gastric cancers represent a distinct subtype of gastric cancers and account for nearly 10% of the gastric cancer burden, yet risk detection strategies for this cancer subtype are lacking. METHODS: We conducted a nested case-control study where we assayed 4 EBV antigens [viral capsid antigen (VCA), early antigen (EA), Epstein-Barr nuclear antigen (EBNA), and BZLF1-encoded replication activator protein (ZEBRA)] in either sera or plasma from 1447 gastric cancer cases and 1797 controls obtained from seven prospective cohorts representing individuals from the high gastric cancer-risk countries of China, Japan, and Korea. RESULTS: The prevalence of EBV sero-positivity was universal with the exception of one sero-negative individual, and the highest titers of the EBV antigens VCA (OR 0.95, 95% CI 0.78-1.17), EBNA (OR 0.88, 95% CI 0.72-1.08), EA (OR 0.97, 95% CI 0.79-1.19), and ZEBRA (OR 0.87, 95% CI 0.71-1.07) were not associated with risk of incident gastric cancer. When we stratified these data by H. pylori status, there was no change in the association. CONCLUSIONS: Multiplex serology of the aforementioned EBV antigens in serum may not be a suitable biomarker for predicting gastric cancer risk in East Asian populations.


Assuntos
Antígenos Virais/análise , Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4/imunologia , Neoplasias Gástricas , Estudos de Casos e Controles , Infecções por Vírus Epstein-Barr/diagnóstico , Infecções por Vírus Epstein-Barr/epidemiologia , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Medição de Risco , Testes Sorológicos/métodos , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/imunologia , Infecções Tumorais por Vírus/epidemiologia
19.
Cancer Epidemiol Biomarkers Prev ; 27(3): 342-344, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29263184

RESUMO

Background: Infection with Helicobacter pylori is the leading risk factor for noncardia gastric cancer, yet its influence on prognosis of gastric cancer is largely unknown. Thus, exploring the role of Helicobacter pylori (H. pylori) in survival could lead to a greater understanding of the high mortality associated with gastric cancer.Methods: Seropositivity to 15 H. pylori antigens was assessed using a multiplex assay in two prospective cohorts, the Shanghai Men's Health Study and the Shanghai Women's Health Study. Multivariable-adjusted Cox proportional hazards regression was used to examine the association between prediagnostic H. pylori antigen levels and gastric cancer-specific survival.Results: Prediagnostic levels of H. pylori serum antibodies that were previously associated with gastric cancer incidence in this population were not associated with gastric cancer survival, whether assessed in a 6-antigen panel [HR = 1.29; 95% confidence interval (CI), 0.78-2.13 for men; HR = 0.93; 95% CI, 0.57-1.52 for women], focused on CagA+H. pylori (HR = 0.73; 95% CI, 0.44-1.20 forwomen; HR = 1.27; 95% CI, 0.70-2.31 for men) or on the high-risk biomarkers of dual Omp and HP 0305 seropositivity (HR = 0.97; 95% CI, 0.72-1.30 for women; HR = 1.37; 95% CI, 0.97-1.94 for men).Conclusions: Prediagnostic H. pylori antigen levels are not associated with gastric cancer survival in East Asian populations.Impact: Identification of additional factors associated with gastric cancer survival would further our understanding of the high mortality associated with this malignancy. Cancer Epidemiol Biomarkers Prev; 27(3); 342-4. ©2017 AACR.


Assuntos
Antígenos de Bactérias/isolamento & purificação , Infecções por Helicobacter/sangue , Helicobacter pylori/isolamento & purificação , Neoplasias Gástricas/mortalidade , Idoso , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/sangue , Antígenos de Bactérias/imunologia , Biomarcadores/sangue , Estudos de Casos e Controles , China/epidemiologia , Feminino , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/imunologia , Humanos , Incidência , Masculino , Prognóstico , Estudos Prospectivos , Fatores de Risco , Neoplasias Gástricas/sangue , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/microbiologia , Análise de Sobrevida
20.
Am J Physiol Gastrointest Liver Physiol ; 311(5): G852-G858, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27758771

RESUMO

Helicobacter pylori (H. pylori) induces chronic gastritis in humans, and infection can persist for decades. One H. pylori strain-specific constituent that augments disease risk is the cag pathogenicity island. The cag island encodes a type IV secretion system (T4SS) that translocates DNA into host cells. Toll-like receptor 9 (TLR9) is an innate immune receptor that detects hypo-methylated CpG DNA motifs. In this study, we sought to define the role of the H. pylori cag T4SS on TLR9-mediated responses in vivo. H. pylori strain PMSS1 or its cagE- mutant, which fails to assemble a T4SS, were used to infect wild-type or Tlr9-/- C57BL/6 mice. PMSS1-infected Tlr9-/- mice developed significantly higher levels of inflammation, despite similar levels of colonization density, compared with PMSS1-infected wild-type mice. These changes were cag dependent, as both mouse genotypes infected with the cagE- mutant only developed minimal inflammation. Tlr9-/- genotypes did not alter the microbial phenotypes of in vivo-adapted H. pylori strains; therefore, we examined host immunological responses. There were no differences in levels of TH1 or TH2 cytokines in infected mice when stratified by host genotype. However, gastric mucosal levels of IL-17 were significantly increased in infected Tlr9-/- mice compared with infected wild-type mice, and H. pylori infection of IL-17A-/- mice concordantly led to significantly decreased levels of gastritis. Thus loss of Tlr9 selectively augments the intensity of IL-17-driven immune responses to H. pylori in a cag T4SS-dependent manner. These results suggest that H. pylori utilizes the cag T4SS to manipulate the intensity of the host immune response.


Assuntos
Infecções por Helicobacter/metabolismo , Inflamação/metabolismo , Receptor Toll-Like 9/metabolismo , Animais , Mucosa Gástrica/metabolismo , Helicobacter pylori , Interleucina-17/genética , Interleucina-17/metabolismo , Camundongos , Camundongos Knockout , Receptor Toll-Like 9/genética
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