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1.
Microorganisms ; 11(10)2023 Sep 28.
Article in English | MEDLINE | ID: mdl-37894080

ABSTRACT

SARS-CoV-2 diagnostic tests have become an important tool for pandemic control. Among the alternatives for COVID-19 diagnosis, antigen rapid diagnostic tests (Ag-RDT) are very convenient and widely used. However, as SARS-CoV-2 variants may continuously emerge, the replacement of tests and reagents may be required to maintain the sensitivity of Ag-RDTs. Here, we describe the development and validation of an Ag-RDT during an outbreak of the Omicron variant, including the characterization of a new monoclonal antibody (anti-DTC-N 1B3 mAb) that recognizes the Nucleocapsid protein (N). The anti-DTC-N 1B3 mAb recognized the sequence TFPPTEPKKDKKK located at the C-terminus of the N protein of main SARS-CoV-2 variants of concern. Accordingly, the Ag-RDT prototypes using the anti-DTC-N 1B3 mAB detected all the SARS-CoV-2 variants-Wuhan, Alpha, Gamma, Delta, P2 and Omicron. The performance of the best prototype (sensitivity of 95.2% for samples with Ct ≤ 25; specificity of 98.3% and overall accuracy of 85.0%) met the WHO recommendations. Moreover, results from a patients' follow-up study indicated that, if performed within the first three days after onset of symptoms, the Ag-RDT displayed 100% sensitivity. Thus, the new mAb and the Ag-RDT developed herein may constitute alternative tools for COVID-19 point-of-care diagnosis and epidemiological surveillance.

2.
Viruses ; 14(12)2022 12 09.
Article in English | MEDLINE | ID: mdl-36560750

ABSTRACT

Since its first identification in Brazil, the variant of concern (VOC) Gamma has been associated with increased infection and transmission rates, hospitalizations, and deaths. Minas Gerais (MG), the second-largest populated Brazilian state with more than 20 million inhabitants, observed a peak of cases and deaths in March-April 2021. We conducted a surveillance study in 1240 COVID-19-positive samples from 305 municipalities distributed across MG's 28 Regional Health Units (RHU) between 1 March to 27 April 2021. The most common variant was the VOC Gamma (71.2%), followed by the variant of interest (VOI) zeta (12.4%) and VOC alpha (9.6%). Although the predominance of Gamma was found in most of the RHUs, clusters of Zeta and Alpha variants were observed. One Alpha-clustered RHU has a history of high human mobility from countries with Alpha predominance. Other less frequent lineages, such as P.4, P.5, and P.7, were also identified. With our genomic characterization approach, we estimated the introduction of Gamma on 7 January 2021, at RHU Belo Horizonte. Differences in mortality between the Zeta, Gamma and Alpha variants were not observed. We reinforce the importance of vaccination programs to prevent severe cases and deaths during transmission peaks.


Subject(s)
COVID-19 , Humans , Brazil/epidemiology , Retrospective Studies , COVID-19/epidemiology , SARS-CoV-2 , Genomics
3.
PLoS Negl Trop Dis ; 15(10): e0009077, 2021 10.
Article in English | MEDLINE | ID: mdl-34714821

ABSTRACT

Individuals with asymptomatic infection due to Plasmodium vivax are posited to be important reservoirs of malaria transmission in endemic regions. Here we studied a cohort of P. vivax malaria patients in a suburban area in the Brazilian Amazon. Overall 1,120 individuals were screened for P. vivax infection and 108 (9.6%) had parasitemia detected by qPCR but not by microscopy. Asymptomatic individuals had higher levels of antibodies against P. vivax and similar hematological and biochemical parameters compared to uninfected controls. Blood from asymptomatic individuals with very low parasitemia transmitted P. vivax to the main local vector, Nyssorhynchus darlingi. Lower mosquito infectivity rates were observed when blood from asymptomatic individuals was used in the membrane feeding assay. While blood from symptomatic patients infected 43.4% (199/458) of the mosquitoes, blood from asymptomatic infected 2.5% (43/1,719). However, several asymptomatic individuals maintained parasitemia for several weeks indicating their potential role as an infectious reservoir. These results suggest that asymptomatic individuals are an important source of malaria parasites and Science and Technology for Vaccines granted by Conselho Nacional de may contribute to the transmission of P. vivax in low-endemicity areas of malaria.


Subject(s)
Anopheles/parasitology , Malaria, Vivax/transmission , Plasmodium vivax/physiology , Animals , Anopheles/physiology , Asymptomatic Infections/epidemiology , Blood/parasitology , Brazil/epidemiology , Cohort Studies , Cross-Sectional Studies , Female , Humans , Malaria, Vivax/epidemiology , Malaria, Vivax/parasitology , Male , Middle Aged , Plasmodium vivax/genetics , Seasons
4.
Preprint in English | medRxiv | ID: ppmedrxiv-21259802

ABSTRACT

Genetic variants of SARS-CoV-2 have been emerging and circulating in many places across the world. Rapid detection of these variants is essential since their dissemination can impact transmission rates, diagnostic procedures, disease severity, response to vaccines or patient management. Sanger sequencing has been used as the preferred approach for variant detection among circulating human immunodeficiency and measles virus genotypes. Using primers to amplify a fragment of the SARS-CoV-2 genome encoding part of the Spike protein, we showed that Sanger sequencing allowed us to rapidly detect the introduction and spread of three distinct SARS-CoV-2 variants in two major Brazilian cities. In both cities, after the predominance of variants closely related to the virus first identified in China, the emergence of the P.2 variant was quickly followed by the identification of the P1 variant, which became dominant in less than one month after it was first detected.

5.
Preprint in English | medRxiv | ID: ppmedrxiv-20217208

ABSTRACT

The antiparasitic drug nitazoxanide is widely available and exerts broad-spectrum antiviral activity in vitro. However, there is no evidence of its impact on SARS-CoV-2 infection. In a multicenter, randomized, double-blind, placebo-controlled trial, adult patients who presented up to 3 days after onset of Covid-19 symptoms (dry cough, fever, and/or fatigue) were enrolled. After confirmation of SARS-CoV2 infection by RT-PCR on nasopharyngeal swab, patients were randomized 1:1 to receive either nitazoxanide (500 mg) or placebo, TID, for 5 days. The primary outcome was complete resolution of symptoms. Secondary outcomes were viral load, general laboratory tests, serum biomarkers of inflammation, and hospitalization rate. Adverse events were also assessed. From June 8 to August 20, 2020, 1,575 patients were screened. Of these, 392 (198 placebo, 194 nitazoxanide) were analyzed. Median time from symptom onset to first dose of study drug was 5 (4-5) days. At the 5-day study visit, symptom resolution did not differ between the nitazoxanide and placebo arms. However, at the 1-week follow-up, 78% in the nitazoxanide arm and 57% in the placebo arm reported complete resolution of symptoms (p=0.048). Swabs collected were negative for SARS-CoV-2 in 29.9% of patients in the nitazoxanide arm versus 18.2% in the placebo arm (p=0.009). Viral load was also reduced after nitazoxanide compared to placebo (p=0.006). No serious adverse events were observed. In patients with mild Covid-19, symptom resolution did not differ between the nitazoxanide and placebo groups after 5 days of therapy. However, early nitazoxanide therapy was safe and reduced viral load significantly. Take home messageThis was the first study to evaluate the effect of early nitazoxanide therapy in mild Covid-19. Nitazoxanide did not accelerate symptom resolution after 5 days of therapy; however, reduced viral load significantly with no serious adverse events.

6.
Microb Pathog ; 133: 103548, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31112771

ABSTRACT

One of the major challenges in Nile tilapia (Oreochromis niloticus L.) farming is the occurrence of bacterial infections, and the Francisella noatunensis subsp. orientalis (FNO) is an important pathogen that has emerged in last decades. Francisellosis outbreaks have been reported in the literature as occurring seasonally when water temperature is below 24 °C. The aim of this study was to quantify the median lethal doses (LD50) of FNO in experimental challenges at 28 °C and 22 °C, and to investigate the impact of temperature changes in whole genome expression using microarray technology. The LD50 for Nile tilapia at 28 °C was ∼105.7, whereas at 22 °C, the LD50 was ∼102.2, showing that the decrease in temperature enhanced disease outcome. Out of 1917 genes screened, a total of 31 and 19 genes were down- and up-regulated at 22 °C, respectively. These genes were grouped by orthology into functional categories of: amino acid, inorganic ion, and carbohydrate transport and metabolism; transcription; and posttranslational modification, protein turnover, and chaperones. Expression of genes related to metabolism, oxidative stress, and thermal shock were regulated by temperature changes, reflecting an ability of FNO to adapt to the environment. Expression of virulence genes usually required for the Francisella genus was not changed between tested temperatures, including that of genes located on the Francisella Pathogenicity Island.


Subject(s)
Fish Diseases/microbiology , Fishes/microbiology , Francisella/genetics , Francisella/metabolism , Francisella/pathogenicity , Gram-Negative Bacterial Infections/veterinary , Temperature , Transcriptome , Animals , Cichlids/microbiology , Down-Regulation , Gene Expression Regulation, Bacterial , Genes, Bacterial/genetics , Gram-Negative Bacterial Infections/microbiology , Lethal Dose 50 , Oxidative Stress , Up-Regulation , Virulence/genetics
7.
Genomics ; 110(6): 442-449, 2018 11.
Article in English | MEDLINE | ID: mdl-30367926

ABSTRACT

Francisella noatunensis subsp. orientalis (FNO) is an important emerging pathogen associated with disease outbreaks in farm-raised Nile tilapia. FNO genetic diversity using PCR-based typing, no intra-species discrimination was achieved among isolates/strains from different countries, thus demonstrating a clonal behaviour pattern. In this study, we aimed to evaluate the population structure of FNO isolates by comparing whole-genome sequencing data. The analysis of recombination showed that Brazilian isolates group formed a clonal population; whereas other lineages are also supported by this analysis for isolates from foreign countries. The whole-genome multilocus sequence typing (wgMLST) analysis showed varying numbers of dissimilar alleles, suggesting that the Brazilian clonal population are in expansion. Each Brazilian isolate could be identified as a single node by high-resolution gene-by-gene approach, presenting slight genetic differences associated to mutational events. The common ancestry node suggests a single entry into the country before 2012, and the rapid dissemination of this infectious agent may be linked to market sales of infected fingerlings.


Subject(s)
Francisella/genetics , Whole Genome Sequencing , Bacterial Typing Techniques , DNA, Bacterial , Francisella/classification , Genetic Variation , Genomics , Multilocus Sequence Typing
8.
Anaerobe ; 40: 76-84, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27311833

ABSTRACT

The epidemiology of Clostridium difficile infections is highly dynamic as new strains continue to emerge worldwide. Here we present a detailed analysis of a new C. difficile strain (ICC-45) recovered from a cancer patient in Brazil that died from severe diarrhea. A polyphasic approach assigned a new PCR-ribotype and PFGE macrorestriction pattern to strain ICC-45, which is toxigenic (tcdA(+), tcdB(+) and ctdB(+)) and classified as ST41 from MLST Clade 2 and toxinotype IXb. Strain ICC-45 encodes for a variant TcdB that induces a distinct CPE in agreement with its toxinotype. Unlike epidemic NAP1/027 strains, which are also classified to MLST Clade 2, strain ICC-45 is susceptible to fluoroquinolones and does not overproduce toxins TcdA and TcdB. However, supernatants from strain ICC-45 and a NAP1/027 strain produced similar expression of pro-inflammatory cytokines, epithelial damage, and oxidative stress response in the mouse ileal loop model. These results highlight inflammation and oxidative stress as common features in the pathogenesis of C. difficile Clade 2 strains. Finally, this work contributes to the description of differences in virulence among various C. difficile strains.


Subject(s)
Bacterial Proteins/genetics , Bacterial Toxins/genetics , Clostridioides difficile/isolation & purification , Diarrhea/diagnosis , Enterocolitis, Pseudomembranous/diagnosis , Neoplasms/diagnosis , Adult , Animals , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/metabolism , Bacterial Toxins/metabolism , Clostridioides difficile/classification , Clostridioides difficile/drug effects , Clostridioides difficile/genetics , Diarrhea/complications , Diarrhea/microbiology , Disease Models, Animal , Enterocolitis, Pseudomembranous/complications , Enterocolitis, Pseudomembranous/drug therapy , Enterocolitis, Pseudomembranous/microbiology , Female , Gene Expression , Humans , Intestinal Mucosa/microbiology , Intestinal Mucosa/pathology , Male , Mice , Multilocus Sequence Typing , Neoplasms/complications , Neoplasms/microbiology , Oxidative Stress , Phylogeny , Polymerase Chain Reaction , Ribotyping
9.
Stand Genomic Sci ; 11: 39, 2016.
Article in English | MEDLINE | ID: mdl-27274785

ABSTRACT

Streptococcus agalactiae, also referred to as Group B Streptococcus, is a frequent resident of the rectovaginal tract in humans, and a major cause of neonatal infection. The pathogen can also infect adults with underlying disease, particularly the elderly and immunocompromised ones. In addition, S. agalactiae is a known fish pathogen, which compromises food safety and represents a zoonotic hazard. This study provides valuable structural, functional and evolutionary genomic information of a human S. agalactiae serotype Ia (ST-103) GBS85147 strain isolated from the oropharynx of an adult patient from Rio de Janeiro, thereby representing the first human isolate in Brazil. We used the Ion Torrent PGM platform with the 200 bp fragment library sequencing kit. The sequencing generated 578,082,183 bp, distributed among 2,973,022 reads, resulting in an approximately 246-fold mean coverage depth and was assembled using the Mira Assembler v3.9.18. The S. agalactiae strain GBS85147 comprises of a circular chromosome with a final genome length of 1,996,151 bp containing 1,915 protein-coding genes, 18 rRNA, 63 tRNA, 2 pseudogenes and a G + C content of 35.48 %.

10.
BMC Genomics ; 17: 315, 2016 Apr 30.
Article in English | MEDLINE | ID: mdl-27129708

ABSTRACT

BACKGROUND: Studies have detected mis-assemblies in genomes of the species Corynebacterium pseudotuberculosis. These new discover have been possible due to the evolution of the Next-Generation Sequencing platforms, which have provided sequencing with accuracy and reduced costs. In addition, the improving of techniques for construction of high accuracy genomic maps, for example, Whole-genome mapping (WGM) (OpGen Inc), have allow high-resolution assembly that can detect large rearrangements. RESULTS: In this work, we present the resequencing of Corynebacterium pseudotuberculosis strain 1002 (Cp1002). Cp1002 was the first strain of this species sequenced in Brazil, and its genome has been used as model for several studies in silico of caseous lymphadenitis disease. The sequencing was performed using the platform Ion PGM and fragment library (200 bp kit). A restriction map was constructed, using the technique of WGM with the enzyme KpnI. After the new assembly process, using WGM as scaffolder, we detected a large inversion with size bigger than one-half of genome. A specific analysis using BLAST and NR database shows that the inversion occurs between two homology RNA ribosomal regions. CONCLUSION: In conclusion, the results showed by WGM could be used to detect mismatches in assemblies, providing genomic maps with high resolution and allow assemblies with more accuracy and completeness. The new assembly of C. pseudotuberculosis was deposited in GenBank under the accession no. CP012837.


Subject(s)
Chromosome Mapping/methods , Corynebacterium pseudotuberculosis/genetics , Genome, Bacterial , Genomics/methods , rRNA Operon/genetics , DNA, Bacterial/genetics , Gene Library , High-Throughput Nucleotide Sequencing , Sequence Analysis, DNA
11.
Stand Genomic Sci ; 11: 30, 2016.
Article in English | MEDLINE | ID: mdl-27073591

ABSTRACT

The genus Francisella is composed of Gram-negative, pleomorphic, strictly aerobic and non-motile bacteria, which are capable of infecting a variety of terrestrial and aquatic animals, among which Francisella noatunensis subsp. orientalis stands out as the causative agent of pyogranulomatous and granulomatous infections in fish. Accordingly, F. noatunensis subsp. orientalis is responsible for high mortality rates in freshwater fish, especially Nile Tilapia. In the current study, we present the genome sequences of F. noatunensis subsp. orientalis strains FNO12, FNO24 and FNO190. The genomes include one circular chromosome of 1,859,720 bp, consisting of 32 % GC content, 1538 coded proteins and 363 pseudogenes for FNO12; one circular chromosome of 1,862,322 bp, consisting of 32 % GC content, 1537 coded proteins and 365 pseudogenes for FNO24; and one circular chromosome of 1,859,595 bp, consisting of 32 % GC content, 1539 coded proteins and 362 pseudogenes for FNO190. All genomes have similar genetic content, implicating a clonal-like behavior for this species.

12.
J Genomics ; 4: 7-9, 2016.
Article in English | MEDLINE | ID: mdl-26958092

ABSTRACT

The species Corynebacterium renale, Corynebacterium pilosum, and Corynebacterium cystitidis were initially thought to be the same species C. renale, but with different immunological types. These bacteria are the causative agent of cystitis, urethritis and pyelonephritis and are found usually as constituents of the normal flora in the lower urogenital tract of cattle. Therefore, we present the draft genome sequences of two pathogenic Corynebacterium species: C. renale CIP 52.96 and C. pilosum CIP 103422. The genome sequences of these species have 2,322,762 bp with 2,218 protein encoding genes and 2,548,014 bp with 2,428 protein encoding genes, respectively. These genomes can help clarify the virulence mechanisms of these unknown bacteria and enable the development of more effective methods for control.

13.
Oncotarget ; 6(25): 20902-20, 2015 Aug 28.
Article in English | MEDLINE | ID: mdl-26041877

ABSTRACT

Oral squamous cell carcinoma (OSCC) is the most common tumor of the oral cavity and has been associated with poor prognosis. Scarce prognostic markers are available for guiding treatment and/or sub-classifying patients. This study aims to identify biomarkers by searching for genes whose expression is increased or decreased during tumor progression (through T1 to T4 stages). Thirty-six samples from all tumor size stages (from T1 to T4) were analyzed using cDNA microarrays. Selected targets were analyzed by immunohistochemistry and in circulating tumor cells by immunofluorescence and Nanostring. Correlation was shown between PD-L1 and tumor size and lymph node metastasis, HOXB9 and tumor size, BLNK and perineural invasion, and between ZNF813 and perineural invasion. PD-L1 positivity was an independent prognostic factor in this cohort (p = 0.044, HH = 0.426). In CTCs from patients with locally advanced OSCC, we found a strong cytoplasmatic expression of PD-L1. PD-L1 is a ligand of PD-1 and is believed to limit T cell activity in inflammatory responses and limit autoimmune diseases. We demonstrated an important role for PD-L1 in primary tumors according to tumor size, and in disease specific survival. Therefore, we could further determine individuals with PD-L1+ CTCs, and possibly follow treatment using CTCs.


Subject(s)
B7-H1 Antigen/genetics , B7-H1 Antigen/metabolism , Carcinoma, Squamous Cell/genetics , Gene Expression Regulation, Neoplastic , Mouth Neoplasms/genetics , Neoplastic Cells, Circulating/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Adult , Aged , Aged, 80 and over , Autoimmune Diseases/metabolism , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Carcinoma, Squamous Cell/blood , Carcinoma, Squamous Cell/mortality , Cohort Studies , Cytoplasm/metabolism , DNA-Binding Proteins/metabolism , Female , Gene Expression Profiling , Homeodomain Proteins/metabolism , Humans , Kaplan-Meier Estimate , Lymphatic Metastasis , Male , Middle Aged , Mouth Neoplasms/blood , Mouth Neoplasms/mortality , Oligonucleotide Array Sequence Analysis , Prognosis , Proportional Hazards Models , Tissue Banks , Treatment Outcome
14.
Genome Announc ; 3(2)2015 Mar 12.
Article in English | MEDLINE | ID: mdl-25767241

ABSTRACT

Here, we present the genome sequence of Corynebacterium ulcerans strain FRC11. The genome includes one circular chromosome of 2,442,826 bp (53.35% G+C content), and 2,210 genes were predicted, 2,146 of which are putative protein-coding genes, with 12 rRNAs and 51 tRNAs; 1 pseudogene was also identified.

15.
Leuk Res ; 38(2): 218-24, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24314588

ABSTRACT

Some studies show that alterations in expression of proteins related to mitotic spindle (AURORAS KINASE A and B) and mitotic checkpoint (CDC20 and MAD2L1) are involved in chromosomal instability and tumor progression in various solid and hematologic malignancies. This study aimed to evaluate these genes in MDS patients. The cytogenetics analysis was carried out by G-banding, AURKA and AURKB amplification was performed using FISH, and AURKA, AURKB, CDC20 and MAD2L1 gene expression was performed by qRT-PCR in 61 samples of bone marrow from MDS patients. AURKA gene amplification was observed in 10% of the cases, which also showed higher expression levels than the control group (p=0.038). Patients with normo/hypercellular BM presented significantly higher expression levels than hypocellular BM patients, but normo and hypercellular BM groups did not differ. After logistic regression analysis, our results showed that HIGH expression levels were associated with increased risk of developing normo/hypercellular MDS. It also indicated that age is associated with AURKA, CDC20 and MAD2L1 HIGH expression levels. The distinct expression of hypocellular patients emphasizes the prognostic importance of cellularity to MDS. The amplification/high expression of AURKA suggests that the increased expression of this gene may be related to the pathogenesis of disease.


Subject(s)
Cell Cycle Checkpoints/physiology , Cell Cycle Proteins/physiology , Myelodysplastic Syndromes/pathology , Spindle Apparatus/physiology , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Karyotype , Male , Middle Aged , Myelodysplastic Syndromes/classification , Myelodysplastic Syndromes/genetics , Young Adult
16.
PLoS One ; 8(3): e57581, 2013.
Article in English | MEDLINE | ID: mdl-23469205

ABSTRACT

Germline mutations in BRCA1, BRCA2 and TP53 genes have been identified as one of the most important disease-causing issues in young breast cancer patients worldwide. The specific defective biological processes that trigger germline mutation-associated and -negative tumors remain unclear. To delineate an initial portrait of Brazilian early-onset breast cancer, we performed an investigation combining both germline and tumor analysis. Germline screening of the BRCA1, BRCA2, CHEK2 (c.1100delC) and TP53 genes was performed in 54 unrelated patients <35 y; their tumors were investigated with respect to transcriptional and genomic profiles as well as hormonal receptors and HER2 expression/amplification. Germline mutations were detected in 12 out of 54 patients (22%) [7 in BRCA1 (13%), 4 in BRCA2 (7%) and one in TP53 (2%) gene]. A cancer familial history was present in 31.4% of the unrelated patients, from them 43.7% were carriers for germline mutation (37.5% in BRCA1 and in 6.2% in the BRCA2 genes). Fifty percent of the unrelated patients with hormone receptor-negative tumors carried BRCA1 mutations, percentage increasing to 83% in cases with familial history of cancer. Over-representation of DNA damage-, cellular and cell cycle-related processes was detected in the up-regulated genes of BRCA1/2-associated tumors, whereas cell and embryo development-related processes were over-represented in the up-regulated genes of BRCA1/2-negative tumors, suggesting distinct mechanisms driving the tumorigenesis. An initial portrait of the early-onset breast cancer patients in Brazil was generated pointing out that hormone receptor-negative tumors and positive familial history are two major risk factors for detection of a BRCA1 germline mutation. Additionally, the data revealed molecular factors that potentially trigger the tumor development in young patients.


Subject(s)
BRCA1 Protein/genetics , BRCA2 Protein/genetics , Breast Neoplasms/genetics , Carcinoma/genetics , Gene Expression Regulation, Neoplastic , Germ-Line Mutation , Tumor Suppressor Protein p53/genetics , Adult , Age of Onset , Brazil/epidemiology , Breast Neoplasms/epidemiology , Carcinoma/epidemiology , Cell Transformation, Neoplastic/genetics , DNA Mutational Analysis , Female , Gene Expression Profiling , Humans , Inheritance Patterns , Pedigree , Receptor, ErbB-2/deficiency , Receptor, ErbB-2/genetics
17.
Cytokine ; 62(2): 217-25, 2013 May.
Article in English | MEDLINE | ID: mdl-23534980

ABSTRACT

BACKGROUND: Cutaneous melanoma displays high morbidity and mortality rates. Isolated limb perfusion with melphalan (Mel) is used for the treatment of non-resectable, locally advanced extremity melanomas. When combined with tumor necrosis factor alpha (TNF-alpha) treatment, the complete response varies between 70% and 90%. The mechanisms underlying the effects of Mel and TNF-alpha are not completely understood. We evaluated the impact of systemic Mel and TNF-alpha administration on tumor growth, analyzed the morphological changes promoted by each treatment, and identified early expressed genes in response to Mel and TNF-alpha treatment, either alone or in combination, in a murine melanoma model. METHODS: Six- to eight-week-old male mice were subcutaneously inoculated with B16F10 melanoma cells and then intravenously injected with TNF-alpha, melphalan or a combination of both drugs when the tumors reached 1.0 cm(2). Tumor growth was monitored every other day, and histological analysis was performed when the tumors reached 3.0 cm(2). Total RNA was extracted from the resected tumors and submitted to amplification, labeling and hybridization on an oligonucleotide microarray (Fox Chase Cancer Center). Tumor growth and histological parameters were compared using ANOVA. Survival curves were calculated using the Kaplan-Meier method. Two-way ANOVA was used to identify differentially expressed genes among the various treatments, and Dunn's test was used for pair-wise comparisons. RESULTS: Systemic administration of Mel impaired tumor growth (p<0.001), improved animal survival (p<0.001), and decreased mitotic rate (p=0.049). Treatment with TNF-alpha alone had no impact, neither on tumor growth, nor on survival, but it increased necrosis (p<0.024) and decreased mitotic rates (p=0.001) in the tumors. Combined treatment with Mel and TNF-alpha had similar effects in tumor growth, survival, necrosis and mitotic rate as observed with individual treatments. Moreover, 118 genes were found differentially expressed by microarray analysis and 10% of them were validated by RT- real time PCR. In our model we found that the treatments regulate genes that play important roles in tumorigenesis such as cell adhesion (Pard3, Pecam1, Ilk, and Dlg5), proliferation (Tcfe3 and Polr1e), cell motility (Kifap3, Palld, and Arhgef6), apoptosis (Bcl2l11), and angiogenesis (Flt1 and Ptprj). CONCLUSIONS: Our data reproduces, in mice, some of the features observed in melanoma patients treated with the combination of Mel and TNF-alpha. The identification of genes with altered expression by these drugs both individually and in combination might help in the understanding of their mechanism of action and, as a consequence, improved strategies that could impact their clinical application.


Subject(s)
Antineoplastic Agents, Alkylating/therapeutic use , Melanoma/drug therapy , Melphalan/therapeutic use , Tumor Necrosis Factor-alpha/therapeutic use , Animals , Apoptosis/drug effects , Apoptosis/genetics , Cell Adhesion/drug effects , Cell Adhesion/genetics , Cell Line, Tumor , Cell Movement/drug effects , Cell Movement/genetics , Cell Proliferation/drug effects , Cell Survival/drug effects , Gene Expression Profiling , Male , Melanoma/genetics , Mice , Mice, Inbred C57BL , Neoplasm Transplantation , Neovascularization, Pathologic/genetics , Treatment Outcome
19.
Infect Immun ; 79(2): 653-62, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21115723

ABSTRACT

Toxin A (TxA) is able to induce most of the classical features of Clostridium difficile-associated disease in animal models. The objective of this study was to determine the effect of an inhibitor of adenosine deaminase, EHNA [erythro-9-(2-hydroxy-3-nonyl)-adenine], on TxA-induced enteritis in C57BL6 mice and on the gene expression of adenosine receptors. EHNA (90 µmol/kg) or phosphate-buffered saline (PBS) was injected intraperitoneally (i.p.) 30 min prior to TxA (50 µg) or PBS injection into the ileal loop. A(2A) adenosine receptor agonist (ATL313; 5 nM) was injected in the ileal loop immediately before TxA (50 µg) in mice pretreated with EHNA. The animals were euthanized 3 h later. The changes in the tissue were assessed by the evaluation of ileal loop weight/length and secretion volume/length ratios, histological analysis, myeloperoxidase assay (MPO), the local expression of inducible nitric oxide synthase (NOS2), pentraxin 3 (PTX3), NF-κB, tumor necrosis factor alpha (TNF-α), and interleukin-1ß (IL-1ß) by immunohistochemistry and/or quantitative reverse transcription-PCR (qRT-PCR). The gene expression profiles of A1, A(2A), A(2B), and A3 adenosine receptors also were evaluated by qRT-PCR. Adenosine deaminase inhibition, by EHNA, reduced tissue injury, neutrophil infiltration, and the levels of proinflammatory cytokines (TNF-α and IL-1ß) as well as the expression of NOS2, NF-κB, and PTX3 in the ileum of mice injected with TxA. ATL313 had no additional effect on EHNA action. TxA increased the gene expression of A1 and A(2A) adenosine receptors. Our findings show that the inhibition of adenosine deaminase by EHNA can prevent Clostridium difficile TxA-induced damage and inflammation possibly through the A(2A) adenosine receptor, suggesting that the modulation of adenosine/adenosine deaminase represents an important tool in the management of C. difficile-induced disease.


Subject(s)
Adenine/analogs & derivatives , Adenosine Deaminase Inhibitors/pharmacology , Adenosine Deaminase/metabolism , Bacterial Toxins/toxicity , Benzyl Compounds/pharmacology , Enteritis/prevention & control , Enterotoxins/toxicity , Adenine/pharmacology , Animals , Bacterial Toxins/administration & dosage , C-Reactive Protein/genetics , C-Reactive Protein/metabolism , Clostridioides difficile/drug effects , Cytokines/genetics , Cytokines/metabolism , Dose-Response Relationship, Drug , Enteritis/chemically induced , Enterocolitis, Pseudomembranous/prevention & control , Enterotoxins/administration & dosage , Gene Expression Regulation/drug effects , Ileum/drug effects , Ileum/pathology , Mice , NF-kappa B/genetics , NF-kappa B/metabolism , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Nitric Oxide Synthase Type II/genetics , Nitric Oxide Synthase Type II/metabolism
20.
Carcinogenesis ; 31(3): 521-31, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20042637

ABSTRACT

Acute expression of E7 oncogene from human papillomavirus (HPV) 16 or HPV18 is sufficient to overcome tumor necrosis factor (TNF)-alpha cytostatic effect on primary human keratinocytes. In the present study, we investigated the molecular basis of E7-induced TNF resistance through a comparative analysis of the effect of this cytokine on the proliferation and global gene expression of normal and E7-expressing keratinocytes. Using E7 functional mutants, we show that E7-induced TNF resistance correlates with its ability to mediate pRb degradation and cell transformation. On the other hand, this effect does not depend on E7 sequences required to override DNA damage-induced cell cycle arrest or extend keratinocyte life span. Furthermore, we identified a group of 66 genes whose expression pattern differs between normal and E7-expressing cells upon cytokine treatment. These genes are mainly involved in cell cycle regulation suggesting that their altered expression may contribute to sustained cell proliferation even in the presence of a cytostatic stimulus. Differential expression of TCN1 (transcobalamin I), IFI44 (Interferon-induced protein 44), HMGB2 (high-mobility group box 2) and FUS [Fusion (involved in t(12;16) in malignant liposarcoma)] among other genes were further confirmed by western-blot and/or real-time polymerase chain reaction. Moreover, FUS upregulation was detected in HPV-positive cervical high-grade squamous intraepithelial lesions when compared with normal cervical tissue. Further evaluation of the role of such genes in TNF resistance and HPV-associated disease development is warranted.


Subject(s)
Gene Expression Profiling , Gene Expression Regulation, Viral , Human papillomavirus 16/physiology , Keratinocytes/virology , Papillomavirus E7 Proteins/physiology , Tumor Necrosis Factor-alpha/pharmacology , Cell Culture Techniques/methods , Cell Division/drug effects , Cell Transformation, Viral/genetics , Cells, Cultured/drug effects , Cells, Cultured/metabolism , Cells, Cultured/virology , DNA Damage , DNA Replication , Drug Resistance , Gene Expression/drug effects , Genes, cdc , Humans , Keratinocytes/drug effects , Keratinocytes/metabolism , Male , Molecular Sequence Data , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Retinoblastoma Protein/metabolism , S Phase
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