ABSTRACT
Lysosomes play important roles in catabolism, nutrient sensing, metabolic signaling, and homeostasis. NPC1 deficiency disrupts lysosomal function by inducing cholesterol accumulation that leads to early neurodegeneration in Niemann-Pick type C (NPC) disease. Mitochondria pathology and deficits in NPC1 deficient cells are associated with impaired lysosomal proteolysis and metabolic signaling. It is thought that activation of the transcription factor TFEB, an inducer of lysosome biogenesis, restores lysosomal-autophagy activity in lysosomal storage disorders. Here, we investigated the effect of trehalose, a TFEB activator, in the mitochondria pathology of NPC1 mutant fibroblasts in vitro and in mouse developmental Purkinje cells ex vivo. We found that in NPC1 mutant fibroblasts, serum starvation or/and trehalose treatment, both activators of TFEB, reversed mitochondria fragmentation to a more tubular mitochondrion. Trehalose treatment also decreased the accumulation of Filipin+ cholesterol in NPC1 mutant fibroblasts. However, trehalose treatment in cerebellar organotypic slices (COSCs) from wild-type and Npc1nmf164 mice caused mitochondria fragmentation and lack of dendritic growth and degeneration in developmental Purkinje cells. Our data suggest, that although trehalose successfully restores mitochondria length and decreases cholesterol accumulation in NPC1 mutant fibroblasts, in COSCs, Purkinje cells mitochondria and dendritic growth are negatively affected possibly through the overactivation of the TFEB-lysosomal-autophagy pathway.
Subject(s)
Mitochondria , Niemann-Pick Disease, Type C , Trehalose , Animals , Humans , Mice , Cholesterol/metabolism , Fibroblasts/metabolism , Intracellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism , Lysosomes/metabolism , Mitochondria/metabolism , Niemann-Pick C1 Protein , Niemann-Pick Disease, Type C/drug therapy , Niemann-Pick Disease, Type C/genetics , Niemann-Pick Disease, Type C/metabolism , Purkinje Cells/pathology , Trehalose/pharmacologyABSTRACT
The immune system can eliminate tumors, but checkpoints enable immune escape. Here, we identify immune evasion mechanisms using genome-scale in vivo CRISPR screens across cancer models treated with immune checkpoint blockade (ICB). We identify immune evasion genes and important immune inhibitory checkpoints conserved across cancers, including the non-classical major histocompatibility complex class I (MHC class I) molecule Qa-1b/HLA-E. Surprisingly, loss of tumor interferon-γ (IFNγ) signaling sensitizes many models to immunity. The immune inhibitory effects of tumor IFN sensing are mediated through two mechanisms. First, tumor upregulation of classical MHC class I inhibits natural killer cells. Second, IFN-induced expression of Qa-1b inhibits CD8+ T cells via the NKG2A/CD94 receptor, which is induced by ICB. Finally, we show that strong IFN signatures are associated with poor response to ICB in individuals with renal cell carcinoma or melanoma. This study reveals that IFN-mediated upregulation of classical and non-classical MHC class I inhibitory checkpoints can facilitate immune escape.
Subject(s)
CD8-Positive T-Lymphocytes , Neoplasms , Clustered Regularly Interspaced Short Palindromic Repeats/genetics , Histocompatibility Antigens Class I/metabolism , Humans , Immune Checkpoint Inhibitors , Immune Evasion , Interferon-gamma/genetics , Interferon-gamma/metabolism , NK Cell Lectin-Like Receptor Subfamily CABSTRACT
OBJECTIVE: The authors developed a negative-pressure, patient face-mounted antechamber and tested its efficacy as a tool for sequestering aerated particles and improving the safety of endonasal surgical procedures. METHODS: Antechamber prototyping was performed with 3D printing and silicone-elastomer molding. The lowest vacuum settings needed to meet specifications for class I biosafety cabinets (flow rate ≥ 0.38 m/sec) were determined using an anemometer. A cross-validation approach with two different techniques, optical particle sizing and high-speed videography/shadowgraphy, was used to identify the minimum pressures required to sequester aerosolized materials. At the minimum vacuum settings identified, physical parameters were quantified, including flow rate, antechamber pressure, and time to clearance. RESULTS: The minimum tube pressures needed to meet specifications for class I biosafety cabinets were -1.0 and -14.5 mm Hg for the surgical chambers with ("closed face") and without ("open face") the silicone diaphragm covering the operative port, respectively. Optical particle sizing did not detect aerosol generation from surgical drilling at these vacuum settings; however, videography estimated higher thresholds required to contain aerosols, at -6 and -35 mm Hg. Simulation of surgical movement disrupted aerosol containment visualized by shadowgraphy in the open-faced but not the closed-faced version of the mask; however, the closed-face version of the mask required increased negative pressure (-15 mm Hg) to contain aerosols during surgical simulation. CONCLUSIONS: Portable, negative-pressure surgical compartments can contain aerosols from surgical drilling with pressures attainable by standard hospital and clinic vacuums. Future studies are needed to carefully consider the reliability of different techniques for detecting aerosols.
ABSTRACT
Introducción Escoliosis de desarrollo temprano, es aquella escoliosis que se presenta antes de los 10 años de edad secundaria a anomalías estructurales congénitas de la columna, enfermedades neuromusculares, síndromes, o idiopáticamente. Materiales & Métodos Revisión literaria narrativa de todo lo publicado sobre escoliosis de desarrollo temprano durante 2003 al 2018. Resultados Esta deformidad de la columna a temprana edad limitara el crecimiento pulmonar e incapacitara la función respiratoria apropiada, provocando el síndrome de insuficiencia torácica. Históricamente, la historia natural de esta condición puede ser letal y el daño ocasionado por la escoliosis de desarrollo temprano suele ser permanente a pesar de su restauración. Actualmente, la escoliosis de desarrollo temprano se clasifica utilizando la combinación de las variables: edad, etiología, magnitud de la escoliosis y cifosis. Los métodos de tratamiento más utilizados son: enyesado en serie, implantes de distracción costal longitudinal en aleación de titanio, barras de crecimiento dobles, técnica de Shilla™, y barras de crecimiento electromagnéticas. Discusión Indudablemente, es imperativo conocer sus manifestaciones y peculiaridades para poder clasificar, monitorear la severidad, personalizar el tratamiento, detener el deterioro de la columna lo más pronto posible, y prevenir la insuficiencia respiratoria Nivel de evidencia IV
Background Early onset scoliosis presents before the age of 10 years old due to congenital structural anomalies of the thorax, neuromuscular diseases, and syndromes, or is idiopathic. Methods A review of the literature from 2003 to 2018 on the early onset scoliosis. Result A deformity of the spine at an early age limits lung development and proper respiratory function, thereby provoking the onset of a thoracic insufficiency syndrome. Historically, the natural path of this condition can be lethal, and the damage caused by the early onset scoliosis tends to be permanent, regardless of its restoration after the age of 10. The early onset scoliosis classification is currently based on the age, aetiology, and the extent of the deformity. The treatment modalities most often used are: serial casts, vertical expandable prosthetic titanium ribs, double traditional growing rods, Shilla™ growing rods, and magnetically controlled growing rods. Discussion Undoubtedly, it is imperative to know its manifestations and peculiarities in order to classify the disease, as well as to monitor the disease. Treatment should be personalised, and the deterioration of the spine halted as soon as possible, as well as to prevent respiratory insufficiency Level of evidence IV
Subject(s)
Humans , Child , Scoliosis , Spine , Congenital Abnormalities , TherapeuticsABSTRACT
OBJECTIVE: The objective was to estimate the number of hospitalizations associated with influenza and RSV using data from severe acute respiratory infection (SARI) sentinel surveillance from El Alto-La Paz. Bolivia. METHODS: All persons who met the case definition for SARI at one sentinel hospital had a clinical sample collected and analyzed by rRT-PCR for influenza and by indirect immunofluorescence for RSV. The SARI-influenza and SARI-RSV case counts were stratified by six age groups. The proportion of cases captured in the sentinel hospital in relation to the non-sentinel hospitals of area was multiplied by the age-specific census population, to build the denominators. The annual incidence and a 95% confidence interval (CI) were estimated. RESULTS: During 2012-2017, n = 2606 SARI cases were reported (average incidence 120/100 000 inhabitants [95% CI: 116-124]); the average incidence of influenza-associated SARI hospitalization was 15.3/100 000 (95% CI: 14.1-16.7), and the average incidence of RSV-associated SARI hospitalization was 9/100 000 inhabitants (95% CI: 8.1-10.1). The highest incidence of influenza was among those less than one year of age (average 174.7/100 000 [range: 89.1-299.5]), followed by those one to four years of age (average 51.8/100 000 [range: 19.8-115.4]) and then those 65 years of age and older (average 47.7/100 000 [range: 18.8-117]). For RSV, the highest incidence was highest among those less than one year of age (231/100 000 [range: 119.9-322.9]). CONCLUSION: Influenza and RSV represent major causes of hospitalization in La Paz, Bolivia-with the highest burden among children under one year of age. Our estimates support current prevention strategies in this age group.
Subject(s)
Hospitalization/statistics & numerical data , Influenza, Human/epidemiology , Respiratory Syncytial Virus Infections/epidemiology , Sentinel Surveillance , Adolescent , Adult , Aged , Aged, 80 and over , Bolivia/epidemiology , Child , Child, Preschool , Humans , Incidence , Infant , Middle Aged , Respiratory Tract Infections/epidemiology , Risk Factors , Young AdultABSTRACT
Strategies to couple non-steroidal anti-inflammatory drugs (NSAIDs) to a glucosamine hydrochloride salt via an amino acid linker are investigated and a series of novel NSAID-glucosamine bioconjugates have been prepared.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/chemistry , Glucosamine/chemistry , Amino Acids/chemistry , Anti-Inflammatory Agents, Non-Steroidal/chemical synthesis , Molecular StructureABSTRACT
The prevalence of infection caused by different categories of diarrhoeagenic E. coli (DEC) strains, including enteroaggregative (EAEC), enteropathogenic (EPEC), enterotoxigenic (ETEC), enteroinvasive (EIEC) and enterohaemorrhagic (EHEC) E. coli, in children who suffered from diarrhoea (nâ=â3943) or did not have diarrhoea (nâ=â1026) were analysed in two areas in Bolivia over a period of 4 years. We also analysed the seasonality of DEC infections and severity of diarrhoea in children with DEC infection and compared antibiotic resistance in DEC strains isolated from children with and without diarrhoea. Stool samples were analysed for the presence of DEC by culturing followed by PCR. The most prevalent DEC categories in samples from the children were: EAEC (11.2â%); ETEC (6.6â%); EPEC (5.8â%); and EIEC and EHEC (<1â%). DEC strains were isolated significantly more often from diarrhoea cases (21.6â%) than from controls (17.6â%; Pâ=â0.002). The number of children with diarrhoea associated with EAEC, EPEC and ETEC infections peaked in the Bolivian winter (April-September), although the proportion of DEC-positive stool samples was higher during the warm rainy season (October-March). High levels of antibiotic resistance were detected among the DEC strains. In particular, resistance to tetracycline and sulfamethoxazole-trimethoprim was significantly higher in strains isolated from individuals with diarrhoea than in samples from controls. The severity of disease in children infected with EAEC, EPEC and ETEC varied from mild to severe diarrhoea, although disease severity did not differ significantly between the different DEC categories. ETEC, EPEC and EAEC are commonly found in Bolivia and may cause severe disease in children.
Subject(s)
Diarrhea/epidemiology , Diarrhea/pathology , Escherichia coli Infections/epidemiology , Escherichia coli Infections/pathology , Escherichia coli/classification , Bolivia/epidemiology , Child, Preschool , Diarrhea/microbiology , Drug Resistance, Bacterial , Escherichia coli/drug effects , Escherichia coli/genetics , Escherichia coli/isolation & purification , Female , Humans , Infant , Infant, Newborn , Male , Microbial Sensitivity Tests , Polymerase Chain Reaction , Prevalence , SeasonsABSTRACT
OBJECTIVE: To evaluate the effectiveness of two doses of a monovalent rotavirus vaccine (RV1) against hospital admission for rotavirus in Bolivia. DESIGN: Case-control study. SETTING: Six hospitals in Bolivia, between March 2010 and June 2011. PARTICIPANTS: 400 hospital admissions for rotavirus, 1200 non-diarrhea hospital controls, and 718 rotavirus negative hospital controls. MAIN OUTCOME MEASURES: Odds of antecedent vaccination between case patients and controls; effectiveness of vaccination ((1-adjusted odds ratio)×100), adjusted for age and other confounders; and stratified effectiveness by dose, disease severity, age group, and serotype. RESULTS: In comparison with non-diarrhea controls, case patients were more likely to be male and attend day care but less likely to have chronic underlying illness, higher level maternal education, and telephones and computers in their home. Rotavirus negative controls were somewhat more similar to case patients but also were more likely to be male and attend day care and less likely to have higher level maternal education and computers in their homes. The adjusted effectiveness of RV1 against hospital admission for rotavirus was 69% (95% confidence interval 54% to 79%) with rotavirus negative controls and 77% (65% to 84%) with non-diarrhea controls. The effectiveness of one dose of RV1 was 36% and 56%, respectively. With both control groups, protection was sustained through two years of life, with similar efficacy against hospital admission among children under 1 year (64% and 77%) and over 1 year of age (72% and 76%). RV1 provided significant protection against diverse serotypes, partially and fully heterotypic to the G1P[8] vaccine. Effectiveness using the two control groups was 80% and 85% against G9P[8], 74% and 93%% against G3P[8], 59% and 69% against G2P[4], and 80% and 87% against G9P[6] strains. CONCLUSION: The monovalent rotavirus vaccine conferred high protection against hospital admission for diarrhea due to rotavirus in Bolivian children. Protection was sustained through two years of life against diverse serotypes different from the vaccine strain.
Subject(s)
Rotavirus Infections/prevention & control , Rotavirus Vaccines/therapeutic use , Rotavirus/immunology , Vaccination/methods , Bolivia/epidemiology , Child, Preschool , Female , Follow-Up Studies , Humans , Incidence , Infant , Infant, Newborn , Male , Odds Ratio , Retrospective Studies , Rotavirus Infections/epidemiology , Rotavirus Infections/virology , Treatment OutcomeABSTRACT
OBJECTIVES: Rotavirus is the most important etiology of severe diarrhea in Bolivia. The monovalent attenuated human oral rotavirus vaccine Rotarix(®) was introduced in Bolivia in 2008. We describe the molecular epidemiology of circulating rotavirus strains before vaccine introduction. METHODS: Two thousand one hundred thirty-five diarrheal samples were collected from hospitals in four Bolivian cities during 2007-2008. Forty-three percent (445 of 1030 rotavirus-positive samples) were analyzed for G and P genotypes. Among those, 331 were electropherotyped by polyacrylamide gel electrophoresis. Disease severity was quantified using a modified Vesikari scale. RESULTS: Among the 445 samples, five genotypes were found to be prevalent: G9P[8] (33%), G1P[6] (17%), G2P[4] (13%), G9P[6] (12%), and G1P[8] (4%). Co-infections with two or more strains accounted for 14% of samples. The most prevalent strain, G9, showed greater electropherotype diversity compared to other serogroups. Strain G1P[6] generally infected younger children and peaked later in the year than other strains. No particular genotype was associated with a higher severity score, though there was a significant difference in the duration of diarrhea between genotypes. CONCLUSIONS: During the 2-year pre-vaccine period, substantial diversity of rotavirus co-circulating strains was observed. These data constitute a baseline against which changes in circulating strains post-vaccine introduction can be monitored.
Subject(s)
Diarrhea/epidemiology , Diarrhea/virology , Genotype , Rotavirus Infections/epidemiology , Rotavirus Infections/virology , Rotavirus/genetics , Antigens, Viral/genetics , Bolivia/epidemiology , Capsid Proteins/genetics , Child, Preschool , Diarrhea/prevention & control , Genetic Variation , Humans , Infant , Infant, Newborn , Rotavirus/classification , Rotavirus/isolation & purification , Rotavirus Infections/prevention & control , Rotavirus Vaccines/immunology , SeasonsABSTRACT
BACKGROUND: In Bolivia, in 2008, the under-five mortality rate is 54 per 1000 live births. Diarrhea causes 15% of these deaths, and 40% of pediatric diarrhea-related hospitalizations are caused by rotavirus illness (RI). Rotavirus vaccination (RV), subsidized by international donors, is expected to reduce morbidity, mortality, and economic burden to the Bolivian state. Estimates of illness and economic burden of RI and their reduction by RV are essential to the Bolivian state's policies on RV program financing. The goal of this report is to estimate the economic burden of RI and the cost-effectiveness of the RV program. METHODS: To assess treatment costs incurred by the healthcare system, we abstracted medical records from 287 inpatients and 6751 outpatients with acute diarrhea between 2005 and 2006 at 5 sentinel hospitals in 4 geographic regions. RI prevalence rates were estimated from 4 years of national hospital surveillance. We used a decision-analytic model to assess the potential cost-effectiveness of universal RV in Bolivia. RESULTS: Our model estimates that, in a 5-year birth cohort, Bolivia will incur over US$3 million in direct medical costs due to RI. RV reduces, by at least 60%, outpatient visits, hospitalizations, deaths, and total direct medical costs associated with rotavirus diarrhea. Further, RV was cost-savings below a price of US$3.81 per dose and cost-effective below a price of US$194.10 per dose. Diarrheal mortality and hospitalization inputs were the most important drivers of rotavirus vaccine cost-effectiveness. DISCUSSION: Our data will guide Bolivia's funding allocation for RV as international subsidies change.
Subject(s)
Health Care Costs/statistics & numerical data , Rotavirus Infections/epidemiology , Rotavirus Infections/prevention & control , Rotavirus Vaccines/administration & dosage , Rotavirus Vaccines/economics , Vaccination/economics , Bolivia/epidemiology , Child, Preschool , Cost-Benefit Analysis , Female , Humans , Infant , Infant, Newborn , Male , Rotavirus Infections/economicsABSTRACT
OBJECTIVE: Notch signaling has been implicated in cell fate decisions during odontogenesis and tumorigenesis of some odontogenic neoplasms; however, its role in solid/multicystic (SA), unicystic (UA), and recurrent (RA) ameloblastoma remains unclear. The aim of this study was to determine Notch receptor and ligand expressions in these subtypes and to speculate on their significance. METHODS: Notch receptors (Notch1, 2, 3, 4) and ligands (Jagged1, 2, and Delta1) were examined immunohistochemically in SA (n = 23), UA (n = 22), and RA (n = 19). RESULTS: Notch4 overexpression in SA (n = 19/23; 82.6%) compared with UA (n = 1/22; 4.5%) or RA (n = 10/19; 52.6%) (P < .05) suggests positive correlation between Notch4 signaling and ameloblastomas with a solid/multicystic phenotype. Ligand (Jagged1 and Delta1) underexpression compared with their receptors (Notch1, 3, 4) (P < .05) and nonreactivity for Notch2 and Jagged2 in all 3 subsets suggests that ameloblastoma epithelium belongs to an earlier stage of differentiation (equivalent to inner enamel epithelium of developing tooth germ) before lineage commitment. CONCLUSION: Present findings suggest that Notch signaling molecules may play differing roles in the acquisition of different ameloblastoma phenotypes.
Subject(s)
Ameloblastoma/genetics , Intercellular Signaling Peptides and Proteins/biosynthesis , Mandibular Neoplasms/genetics , Maxillary Neoplasms/genetics , Proto-Oncogene Proteins/biosynthesis , Receptors, Notch/biosynthesis , Adolescent , Adult , Aged , Ameloblastoma/classification , Ameloblastoma/metabolism , Ameloblastoma/pathology , Child , Child, Preschool , Epithelium/pathology , Female , Gene Expression Regulation, Neoplastic , Humans , Immunohistochemistry , Intercellular Signaling Peptides and Proteins/genetics , Ligands , Male , Mandibular Neoplasms/classification , Mandibular Neoplasms/metabolism , Mandibular Neoplasms/pathology , Maxillary Neoplasms/classification , Maxillary Neoplasms/metabolism , Maxillary Neoplasms/pathology , Middle Aged , Phenotype , Proto-Oncogene Proteins/genetics , Receptor, Notch4 , Receptors, Notch/genetics , Statistics, Nonparametric , Up-Regulation , Young AdultABSTRACT
In recent years, calcium titanate (CaTiO(3)) and carbon-containing materials have gained much attention in a number of biomedical material researches. To maximize the advantages of both materials, we developed a novel alkoxide method to get "calcium titanate with calcium carbonate" (CaTiO(3)-CaCO(3)). The objective was to evaluate the crystallinity and elemental composition of CaTiO(3)-CaCO(3) prepared by alkoxide method, CaTiO(3)-aC elaborated by modified thermal decomposition method, commercially-prepared CaTiO(3), and the effect of these materials on the bone marrow stromal cell. Hydroxyapatite was used as positive control material. We examined the cellular proliferation, osteoblastic differentiation, and mineralization of KUSA/A1 cells cultured with the materials. The results showed that CaTiO(3)-CaCO(3) and CaTiO(3)-aC contained evidence of calcium carbonate enhancing cell proliferation, osteoblastic differentiation, and mineralization. On the contrary, the commercially-prepared CaTiO(3) revealed absence of calcium carbonate with lower cell response than the other groups. The results indicated that calcium carbonate could play a key role in the cell response of CaTiO(3) material. In conclusion, our findings suggest that CaTiO(3)-CaCO(3) could be considered an important candidate as a biomaterial for medical and dental applications.
Subject(s)
Calcium Carbonate/pharmacology , Calcium Compounds/pharmacology , Materials Testing/methods , Oxides/pharmacology , Stromal Cells/cytology , Stromal Cells/drug effects , Titanium/pharmacology , Alkaline Phosphatase/metabolism , Anthraquinones/metabolism , Calcification, Physiologic/drug effects , Cell Line , Cell Survival/drug effects , Elements , Microscopy, Electron, Scanning , Stromal Cells/enzymology , X-Ray DiffractionABSTRACT
The discovery of ING1 gene paved the way to the identification of other ING members (ING2-5) and their isoforms associated with cell cycle, apoptosis and senescence. The ING family has been an emerging putative tumor suppressor gene (TSG) in which the major mechanism is through interaction with the determinants of chromatin function and gene-specific transcription factors. The regulatory mechanism highly involves the conserved plant homeodomain (PHD), which binds to histones in a methylation-sensitive manner, suggesting that ING proteins may contribute to the maintenance of the epigenetic code. Furthermore, ING family members contain nuclear localization signals and N-terminal sequences important in the interaction with histone acetyltransferase (HAT) and histone deacetyltransferase (HDAC) that regulate gene promoter activity within chromatin. Although ING proteins have the same PHD motif, the variation in the N-terminal dictates the differences in tumor the suppressive ability of ING in various tumors. Inactivation of the normal function is achieved through allelic loss of genomic regions containing the ING gene, alteration in the ING promoter region, variation of mRNA splicing efficacy or reduced mRNA stability. It is most probably the apparent combination of these aberrant mechanisms that resulted in reduced availability of functional ING protein. In cancer cells, ING transcript levels are often suppressed but the genes are rarely mutated. The mechanism of suppression of ING expression may have to do with the abnormally high methylation levels of the ING gene promoter, which have been correlated with low transcript levels. Emerging evidence on the function of ING and related regulatory mechanisms strongly points to ING as a candidate TSG and therefore a potential target in the molecular therapy of some types of tumor.
Subject(s)
Tumor Suppressor Proteins/therapeutic use , Histone Acetyltransferases/metabolism , Humans , Neoplasms/drug therapy , Neoplasms/enzymology , Neoplasms/genetics , RNA Splicing , RNA, Messenger/genetics , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolismABSTRACT
PURPOSE AND METHODS: Loss of heterozygosity (LOH) in a chromosomal location indicates the presence of an inactivated tumor suppressor gene (TSG). Inactivation of TSG has a functional role in the tumorigenesis of head and neck squamous cell carcinoma (HNSCC). Based on the recent evidences of a putative TSG on chromosome 14, we examined LOH on chromosome 14q using eight polymorphic microsatellite markers in 50 cases of HNSCCs. RESULTS: Three regions were detected to have a high LOH rate which included 14q21.2-22.3 (42.5%), 14q31 (55%), and 14q32.1 (37%). The correlation between LOH and clinicopathological findings was investigated through statistical analyses. A strong correlation was observed between the highest LOH marker and the overall and disease-free survival. CONCLUSIONS: The results suggest that the distal part of chromosome 14 may host a TSG that may lead to the development and/or progression of HNSCCs. Several genes such as CHES1, BMP4, SAV, and PNN have arisen as candidate tumor suppressors in the region.
Subject(s)
Carcinoma, Squamous Cell/genetics , Chromosomes, Human, Pair 14/genetics , Head and Neck Neoplasms/genetics , Loss of Heterozygosity , Aged , Carcinoma, Squamous Cell/pathology , Case-Control Studies , Chromosome Deletion , Chromosome Mapping , Female , Genes, Tumor Suppressor , Head and Neck Neoplasms/pathology , Humans , Male , Microsatellite Repeats , Middle Aged , Prognosis , Survival RateABSTRACT
EphA2 is a 130-kDa transmembrane protein primarily found in adult human epithelial cells and is a member of one of the largest receptor tyrosine kinases. It is located on 1p36.1, a genetic hot spot in cancer. EphA2 overexpression has been observed in aggressive solid tumors and its potential role in tumorigenesis, which includes cell growth, survival, migration and angiogenesis have been reported. However, the role of EphA2 remains unknown in head and neck cancer. In this study, we investigated the genetic profile of EphA2 in primary head and neck squamous cell carcinoma (HNSCC) by determining mRNA level, status of loss of heterozygosity and protein expression. mRNA expression was also correlated with clinicopathological data. Infrequent loss of heterozygosity (20%) was observed, though a 10-fold increase of mRNA expression in tumors compared to normal tissues was noted. A significant number of samples with normal to high mRNA expression was observed among patients with regional metastasis, with T3-T4 tumor size and with moderate to poor differentiation. However, statistical studies did not show any correlation between mRNA expression and any of the clinicopathological parameters. Tumor cells expressed EphA2 protein, but only weakly. These results suggest that EphA2 might be involved in the early development of HNSCC although not directly responsible for its progression.
Subject(s)
Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/metabolism , Gene Expression Regulation, Neoplastic , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/metabolism , Loss of Heterozygosity , RNA, Messenger/metabolism , Receptor, EphA2/biosynthesis , Receptor, EphA2/genetics , Aged , Female , Gene Expression Profiling , Humans , Ligands , Male , Middle Aged , Models, Genetic , Neoplasm MetastasisABSTRACT
Oral mucosal melanoma is an aggressive neoplasm with poor prognosis. Heparanase is an endo-beta-d-glucuronidase, which cleaves heparan sulphate chains. The vascular endothelial growth factor (VEGF) is the most potent angiogenic mitogen and interaction with its receptor (VEGFR) has been associated with angiogenesis. We investigated the expression of these molecules in the progression of oral mucosal melanoma. Immunohistochemistry was carried out in 15 oral melanotic macules and 19 oral melanomas using heparanase, VEGF, VEGFR-2, CD34 and Ki-67. Microvessel density was determined and subjected to statistical analysis. Heparanase and VEGFR-2 were not expressed in the oral melanotic macule. Atypical melanocytes and melanoma cells expressed heparanase, VEGF and VEGFR-2. An intense expression was noted in the early invasive phase, which marks the crucial transition from in situ to the invasive phase. In the invasive component, heparanase was intense but selective in the invasive fronts and at the periphery of nests unlike the extensive expression of VEGF and VEGFR-2. However, hot spots were only observed at the periphery of the nests. In conclusion, melanoma cells expressed heparanase, VEGF and VEGFR-2. The coexpression of these molecules in atypical melanocytes and melanoma cells suggests their function in cell migration and invasion. Moreover, the intense expression in the crucial transition from in situ to the invasive phase suggests their role in the progression of the tumor. The role of VEGF and VEGFR-2 in angiogenesis was evident only at the periphery of the nests in the invasive components.
Subject(s)
Glucuronidase/metabolism , Melanoma/pathology , Mouth Mucosa , Mouth Neoplasms/pathology , Vascular Endothelial Growth Factor A/metabolism , Disease Progression , Humans , Melanoma/blood supply , Melanoma/metabolism , Mouth Neoplasms/blood supply , Mouth Neoplasms/metabolism , Vascular Endothelial Growth Factor Receptor-2/metabolismABSTRACT
C-kit is a trans-membrane receptor tyrosine kinase (RTK) encoded by the proto-oncogene KIT located at 4q11-12. Gain-of-function mutations arising to c-kit activation independent of its ligand were observed in various tumors related to germ cells, mast cells, and interstitial cells of Cajal. C-kit also participates in melanocyte development; hence, its involvement in oral mucosal melanoma (OMM) tumorigenesis was investigated. Immunohistochemistry and mutation analysis were performed using 18 cases of human primary OMM. Results revealed 16 cases positive to c-kit protein. Atypical melanocytes expressed c-kit. All in situ components expressed c-kit, but only four cases exhibited intense expression in the invasive component. Missense mutations were observed in four cases, and two of those correlated with increased protein expression. C-kit expression in atypical melanocytes suggests the role of c-kit in the early stage of OMM tumorigenesis. C-kit protein expression correlated with activating mutations indicating the pertinent role of the proto-oncogene KIT in the tumorigenesis of OMM.
Subject(s)
Melanoma/metabolism , Mouth Mucosa/metabolism , Mouth Neoplasms/metabolism , Mutation, Missense , Proto-Oncogene Proteins c-kit/metabolism , Base Sequence , DNA Mutational Analysis , DNA, Neoplasm/analysis , Humans , Immunohistochemistry , Melanocytes/metabolism , Melanocytes/pathology , Melanoma/genetics , Melanoma/pathology , Molecular Sequence Data , Mouth Mucosa/pathology , Mouth Neoplasms/genetics , Mouth Neoplasms/pathology , Polymorphism, Single-Stranded Conformational , Proto-Oncogene Mas , Proto-Oncogene Proteins c-kit/genetics , Sequence Analysis, DNAABSTRACT
BACKGROUND: Keratocystic odontogenic tumor (KCOT), also known as odontogenic keratocyst, is a benign cystic neoplasm, which may be associated with nevoid basal cell carcinoma syndrome (NBCCS) and if it does, will occur as multiple cystic lesions. KCOT is locally destructive despite its bland histological features. However, the neoplastic nature of KCOT is not well established. Heparanase is an endo-d-glucuronidase enzyme that specifically cleaves heparan sulfate (HS) and the increase of its level in tumors promotes invasion, angiogenesis, and metastasis. METHODS: To investigate the neoplastic character of KCOT, we studied the localization patterns of heparanase in KCOT, focusing on the differences between sporadic and NBCCS-associated KCOTs, by immunohistochemistry and in situ hybridization. To compare the expression pattern of these cysts with non-tumorous odontogenic developmental cyst, dentigerous cyst was included. RESULTS: All the odontogenic cysts showed positive immunoreaction for heparanase protein in various intensities. The expression pattern of heparanase gene corresponded to that of protein expression. Interestingly, intense gene and protein expressions were observed in KCOT associated with NBCCS compared with sporadic ones and dentigerous cyst. CONCLUSIONS: The results implied that heparanase expression may be correlated with the neoplastic properties of KCOT, particularly in NBCCS-associated cases.
Subject(s)
Basal Cell Nevus Syndrome/enzymology , Glucuronidase/biosynthesis , Odontogenic Cysts/enzymology , Odontogenic Tumors/enzymology , Basal Cell Nevus Syndrome/complications , Dentigerous Cyst/enzymology , Gene Expression Regulation, Neoplastic , Glucuronidase/genetics , Heparan Sulfate Proteoglycans/metabolism , Humans , Immunohistochemistry , In Situ Hybridization , Neoplasm Invasiveness , Odontogenic Cysts/complications , Odontogenic Tumors/complicationsABSTRACT
The genetic variability and distribution of Amazonian fish species have likely been influenced by major disturbance events in recent geological times. Alternatively, the great diversity of aquatic habitat in the Amazon is likely to shape ongoing gene flow and genetic diversity. In this context, complex patterns of genetic structure originating from a joint influence of historical and contemporary gene flow are to be expected. We explored the relative influence of Pleistocene climatic fluctuations and current water chemistry on the genetic structure of a piranha, Serrasalmus rhombeus, in the Upper Amazon by the simultaneous analysis of intron length polymorphism and mitochondrial DNA sequences. The Madeira river is well suited for that purpose as it is characterized by a great diversity of water types, the presence of one of the largest floodplain of the Amazon and the potential occurrence of two Pleistocene refuges. We found evidence of genetic structure even at a small geographical scale (less than 10 km), indicating that the floodplain is not a homogenizing factor promoting interdrainage dispersal in S. rhombeus. Likewise, the hierarchical genetic structure inferred was correlated to geographical distance instead of habitat characteristic. Our results also support the hypothesis that the area underwent population expansion during the last 800,000 years. In addition, a higher level of genetic diversity was found in the samples from the putative Aripuanã refuge. The present findings suggest that Pleistocene refuges contributed significantly to the colonization of the lowlands in the Upper Amazon valley during the Pleistocene.
Subject(s)
Climate , Fishes/genetics , Fresh Water/chemistry , Genetic Speciation , Genetic Variation , Genetics, Population , Animals , Base Sequence , Brazil , Cluster Analysis , DNA Primers , DNA, Mitochondrial/genetics , Gene Frequency , Geography , Haplotypes/genetics , Introns/genetics , Molecular Sequence Data , Population Dynamics , Rivers , Sequence Analysis, DNAABSTRACT
The present study examined histological difference between ossifying fibromas (OF, n=5) and peripheral cemento-ossifying fibromas (PCOF, n=7). Bone morphogenetic proteins (BMP)-2 and -4, osteopontin (OPN), osteocalcin (OCN) and proliferating cell nuclear antigen (PCNA) were used for the immunohistochemical examinations. Oxytalan fibers present at the periodontal tissue were stained to determine the tumor cell origin. Many OFs showed high immunohistochemical reactions for BMP-2, -4 and OPN compared to those of PCOFs. PCNA index (IP) of OFs was significantly higher than that of PCOFs. All the PCOFs showed a high expression of oxytalan fibers. Only two OFs exhibited a small number of oxytalan fibers. These results suggest that PCOF has only little ability to form hard tissue and seems to be a reactive lesion. The expression of oxytalan fibers reveals that OF does not only originate from periodontal tissue.