COX-2 gene expression and methylation profile in Sapajus apella as an experimental model for gastric adenocarcinoma

<div><p>Abstract Gastric cancer (GC) remains one of the main causes of cancer-related death worldwide. There are two distinct histological types of GC: diffuse and intestinal. The latter is characterized by the presence of pre-neoplastic lesions. One of the most frequently altered enzymes in intestinal GC is COX-2, an important lesion marker. This work aimed to study COX-2 methylation and expression in N-methyl-N-Nitrosurea (MNU)-induced intestinal GC in six Sapajus apella animals. The partial promoter sequence of S. apella COX-2 gene was obtained and used to identify transcription factors and cis-regulatory element binding sites. The COX-2 methylation pattern was assessed using Methylation-Specific PCR (MSP), and expression was analyzed by immunohistochemistry (IHQ). A total of 20 samples were obtained. A 675 bp fragment of the S. apella COX-2 promoter region was obtained, and it was 99.2% and 68.2% similar to H. sapiens and S. boliviensis, respectively. Similar to humans, several transcription factors and cis-regulatory element binding sites were identified in the S. apella sequence. MSP revealed that all samples were methylated. However, IHQ results demonstrated positive COX-2 expression in all pre-neoplastic and tumoral samples. The results suggest that the analyzed fragment is not crucial in COX-2 regulation of GC in S. apella.</p></div

H. pylori infection and virulence factors cagA and vacA (s and m Regions) in gastric adenocarcinoma from Para State, Brazil

Health Surveillance Secretariat of the Brazilian Ministry of Health (SVS/MS) Brasília, Distrito Federal, BrazilMinistério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Laboratório de Imunologia. Ananindeua, PA, BrasilMinistério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Laboratório de Enteroinfecções Bacterianas. Ananindeua, PA, BrasilMinistério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Laboratório de Enteroinfecções Bacterianas. Ananindeua, PA, BrasilUniversidade Federal do Pará. Instituto de Ciências Biológicas. Belém, PA, BrazilMinistério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Laboratório de Células e Tecidos. Ananindeua, PA, BrasilUniversidade Federal do Pará. Laboratório de Citogenética Humana. Belém, PA, BrazilH. pylori shows a great variability in genes associated with virulence, which may influence properties related to gastric adenocarcinoma initiation and progression. Among them, cagA and vacA show a strong positive association with the disease. Therefore, a cross-sectional study was carried out with 281 samples of gastric adenocarcinoma, collected at a cancer reference center in the Brazilian Amazon. Detection of H. pylori was proceeded by PCR of the ureA and 16S genes. Positive samples were subjected to the cagA detection and vacA typing. The bacteria were observed in 32.03% of the samples. Positivity for H. pylori was associated with advanced age (p = 0.0093) and metastases (p = 0.0073). Among the positive cases, 80% (72/90) had the cagA gene. For the “s” position of the vacA gene, 98.8% (83/84) of the bacteria had genotype s1 and 1.2% (1/84) were genotyped as s2. For the “m” position, the results were: 63.6% (56/88) with m1 genotype, 2.3% (2/88) genotyped as m2 and 34.1% (30/88) m1/m2. Virulence factors did not impact an increase in the association with age or metastases. In conclusion, H. pylori infection is associated with malignant phenotype cases of gastric adenocarcinoma, involving metastases. The virulence factors related to the cagA and vacA genes showed a high prevalence in the Brazilian Amazo

Sensitivity to cisplatin-induced mutations and elevated chromosomal aberrations in lymphocytes from sickle cell disease patients

Sickle cell disease (SCD) is an inherited disorder caused by a single nucleotide substitution in the P-globin gene. The clinical heterogeneity observed in SCD patients has been attributed to environmental and genetic factors. The patients are subjected to increased oxidative stress, particularly during vaso-occlusive crises and acute chest pain. Another possible cause of oxidative stress in SCD is the high concentration of iron in the patients` plasma. The increase in oxidative stress could be a relevant risk factor for mutagenesis and carcinogenesis. Studies on the frequency of basal chromosomal aberrations in cultured lymphocytes from SCD patients have not been reported so far. In order to contribute to the understanding of the role of the different biomarkers and their relationship with the extremely variable clinical manifestation of SCD, we investigated the frequency of chromosome damage in peripheral lymphocytes from sickle cells patients and healthy controls. We found an increased frequency of chromosome damage and percentage of aberrant metaphases in these patients when compared with control subjects, even at basal values (p < 0.05). In the cytogenetic sensitivity assay, the results showed that these patients presented a marked decrease in the mitotic index values compared with healthy controls. Cisplatin-induced chromosomal damage in lymphocytes from these patients was significantly higher than the frequency measured in healthy controls. The results obtained in the present study showed that more investigations are needed in order to elucidate the susceptibility to genomic instability of SCD patients

Homocystein, Vitamin B12 and Folic Acid as Screening Biomarkers in Early Diagnosis and Gastric Cancer Monitoring

Gastric cancer has been demonstrating a reduction in the number of cases over the past decades, largely attributed to advancements in public health practices and increased accessibility to educational initiatives for the general population. Nevertheless, it persists as the third leading cause of mortality globally among both men and women. These fatalities are typically associated with delayed disease detection. The current study assessed the levels of homocysteine, vitamin B12, and folic acid as a means of establishing a screening biomarker profile that could be integrated into routine testing protocols to facilitate swift diagnosis of the illness. A total of 207 control subjects and 207 individuals with gastric cancer were scrutinized, with biochemical measurements conducted using chemiluminescence for homocysteine, folic acid, and vitamin B12. The two groups were matched based on age, tumor location, subtype, tumor classification, presence of Epstein-Barr Virus infection (EBV), and Helicobacter pylori (H. pylori). Significant statistical variances were identified in the mean levels of the triad of substances among cancer patients when compared to the control group for all corresponding variables. In conclusion, our study indicated that analyzing the triad of homocysteine, vitamin B12, and folic acid holds diagnostic value for gastric cancer and could potentially serve as an effective screening marker for this type of cancer in the future

Study of Genotoxicity, Activities on Caspase 8 and on the Stabilization of the Topoisomerase Complex of Isoeleutherin and Analogues

This study evaluated the genotoxicity of Ethanol Extract (EEEp), Dichloromethane Fraction (FDCMEp) and isoeleutherin isolated from Eleutherine plicata, using the micronucleus test and the impact of structural alterations on toxicity and molecular docking (topoisomerase II and DNA complex). The extract was obtained by maceration and fractionation in a chromatography column. The genotoxicity was evaluated by the micronucleus test in human hepatoma cells (HepG2). Isoeleutherin was the starting molecule in the search for analogues by structural similarity, using the ZINC and e-Molecules databases. Isoeleutherin and analogues were subjected to in silico toxicity prediction, and compounds free of toxicological risks (CP13, CP14, CP17 and isoeleutherin) were selected for molecular docking in Topoisomerase II (PDB: 1ZXM). In the micronucleus test, isoeleutherin was less genotoxic. Among the 22 isoeleutherin analogues there were variations in the toxicity profile. Molecular docking studies showed that the compounds have good complementarity in the active site with important hydrogens bonds. Therefore, the structural changes of isoeleutherin led to the obtaining of a molecule with a lower mutagenic potential, and the CP13 can be considered a prototype compound for the development of new molecules with pharmacological potential

Study of Genotoxicity, Activities on Caspase 8 and on the Stabilization of the Topoisomerase Complex of Isoeleutherin and Analogues

This study evaluated the genotoxicity of Ethanol Extract (EEEp), Dichloromethane Fraction (FDCMEp) and isoeleutherin isolated from Eleutherine plicata, using the micronucleus test and the impact of structural alterations on toxicity and molecular docking (topoisomerase II and DNA complex). The extract was obtained by maceration and fractionation in a chromatography column. The genotoxicity was evaluated by the micronucleus test in human hepatoma cells (HepG2). Isoeleutherin was the starting molecule in the search for analogues by structural similarity, using the ZINC and e-Molecules databases. Isoeleutherin and analogues were subjected to in silico toxicity prediction, and compounds free of toxicological risks (CP13, CP14, CP17 and isoeleutherin) were selected for molecular docking in Topoisomerase II (PDB: 1ZXM). In the micronucleus test, isoeleutherin was less genotoxic. Among the 22 isoeleutherin analogues there were variations in the toxicity profile. Molecular docking studies showed that the compounds have good complementarity in the active site with important hydrogens bonds. Therefore, the structural changes of isoeleutherin led to the obtaining of a molecule with a lower mutagenic potential, and the CP13 can be considered a prototype compound for the development of new molecules with pharmacological potential

Association study of SNPs of genes IFNGR1 (rs137854905), GSTT1 (rs71748309), and GSTP1 (rs1695) in gastric cancer development in samples of patient in the northern and northeastern Brazil

Cancer is a multifactorial disease with a high mortality rate in Brazil and worldwide. Gastric cancer (GC) is considered the fourth type of malignancy more frequent in the population worldwide and the second leading cause of death. This work aimed to evaluate single nucleotide polymorphisms (SNPs) of IFNGR1, GSTT1, and GSTP1 genes samples in gastric cancer. We analyzed 60 samples of gastric cancer, 26 diffuse and 34 intestinal types, totaling 120 alleles for each SNP. the results were obtained by PCR and allele-specific PCR. Statistical analyzes performed using BioEstat 5.0 software, applying the Fisher's exact test and chi-square. Only the SNP gene GSTP1 (rs1695) were significantly associated with gastric cancer in the samples analyzed (chi (2) = 8.73, P < 0.05). Our results suggest that the GSTP1 gene SNP (rs1695) can be considered a risk factor associated with gastric carcinogenesis.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fed Univ Paraiba UFPB, Dept Mol Biol, Grad Program Cellular & Mol Biol, BR-58051900 Joao Pessoa, Paraiba, BrazilFed Univ Paraiba UFPB, Dept Mol Biol, Lab Struct Mol Biol & Oncogenet LBMEO, BR-58051900 Joao Pessoa, Paraiba, BrazilFed Univ Paraiba UFPB, CCEN, Dept Mol Biol, Lab Struct Mol Biol & Oncogenet LBMEO, BR-58051900 Joao Pessoa, Paraiba, BrazilFed Univ Paraiba UFPB, Dept Med, BR-58051900 Joao Pessoa, Paraiba, BrazilHosp Sao Marcos, Dept Gastroenterol, BR-64001280 Teresina, Piaui, BrazilState Univ Paraiba UEPB, Dept Pharm, BR-58429500 Campina Grande, Paraiba, BrazilUniversidade Federal de São Paulo, Dept Morphol & Genet, BR-04023900 São Paulo, BrazilFed Univ Para, Ctr Biol Sci, Dept Biol, BR-66075110 Belem, Para, BrazilUniversidade Federal de São Paulo, Dept Morphol & Genet, BR-04023900 São Paulo, BrazilWeb of Scienc

Interrelationship between chromosome 8 aneuploidy, C-MYC amplification and increased expression in individuals from northern Brazil with gastric adenocarcinoma

AIM: To investigate chromosome 8 numerical aberrations, C-MYC oncogene alterations and its expression in gastric cancer and to correlate these findings with histopathological characteristics of gastric tumors.METHODS: Specimens were collected surgically from seven patients with gastric adenocarcinomas. Immunostaining for C-MYC and dual-color fluorescence in situ hybridization (FISH) for C-MYC gene and chromosome 8 centromere were performed.RESULTS: All the cases showed chromosome 8 aneuploidy and C-MYC amplification, in both the diffuse and intestinal histopathological types of Lauren. No significant difference (P < 0.05) was observed between the level of chromosome 8 ploidy and the site, stage or histological type of the adenocarcinomas. C-MYC high amplification, like homogeneously stained regions (HSRs) and double minutes (DMs), was observed only in the intestinal-type. Structural rearrangement of C-MYC, like translocation, was observed only in the diffuse type. Regarding C-MYC gene, a significant difference (P < 0.05) was observed between the two histological types. The C-MYC protein was expressed in all the studied cases. In the intestinal-type the C-MYC immunoreactivity was localized only in the nucleus and in the diffuse type in the nucleus and cytoplasm.CONCLUSION: Distinct patterns of alterations between intestinal and diffuse types of gastric tumors support the hypothesis that these types follow different genetic pathways. (C) 2006 The WJG Press. All rights reserved.Fed Univ Para, Ctr Ciencias Biol, Dept Biol, Lab Citogenet Humana & Genet Toxicol, BR-66075900 Belem, Para, BrazilUniv Fed Sao Paulo, Dept Morphol, Div Genet, Sao Paulo, BrazilFed Univ Para, Dept Pathol, BR-66059 Belem, Para, BrazilFed Univ Para, Surg Serv, BR-66059 Belem, Para, BrazilFed Univ Para, Joao de Barros Barreto Univ Hosp, BR-66059 Belem, Para, BrazilFed Univ Ceara, Sch Med, Dept Pathol, Genet Mol Lab, Fortaleza, Ceara, BrazilUniv Fed Sao Paulo, Dept Morphol, Div Genet, Sao Paulo, BrazilWeb of Scienc

Hepatitis C and Human Pegivirus Coinfection in Patients with Chronic Hepatitis C from the Brazilian Amazon Region: Prevalence, Genotypes and Clinical Data

Coinfection of HPgV-1 with hepatitis C virus (HCV) is common due to shared modes of transmission, with a prevalence of HPgV-1 viremia of approximately 20% among individuals with chronic HCV infection. The aim of the present study was to estimate the prevalence of HPgV-1 RNA and circulating genotypes in patients with hepatitis C from a health service located in the city of Belém, in the state of Pará, Northern Brazil. A total of 147 samples were included in the study from February to December 2019. Among the participants, 72.1% (106/147) were monoinfected with HCV, with detectable HCV viral RNA, and 27.9% (41/147) were coinfected with HCV/HPgV-1. The most frequently found genotypes were HPgV-1 genotypes 1 and 2 (36.6% and 63.4%), respectively. While for HCV there was a predominance of genotypes 1 and 3 (58.5% and 41.5%). No significant differences were found when comparing any risk, sociodemographic, or clinical factors between groups. Also, there was no statistically significant difference when relating the viral genotypes of both agents. This study indicated that the prevalence of infection by HPgV-1 is high in HCV carriers in Belém, Pará, and probably does not change the clinical course of HCV infection, however, further studies are still needed

Molecular Changes in the Brain of the Wintering <i>Calidris pusilla</i> in the Mangroves of the Amazon River Estuary

Migrant birds prepare differently to fly north for breeding in the spring and for the flight to lower latitudes during autumn, avoiding the cold and food shortages of the Northern Hemisphere’s harsh winter. The molecular events associated with these fundamental stages in the life history of migrants include the differential gene expression in different tissues. Semipalmated sandpipers (Calidris pusilla) are Arctic-breeding shorebirds that migrate to the coast of South America during the non-breeding season. In a previous study, we demonstrated that between the beginning and the end of the wintering period, substantial glial changes and neurogenesis occur in the brain of C. pusilla. These changes follow the epic journey of the autumn migration when a 5-day non-stop transatlantic flight towards the coast of South America and the subsequent preparation for the long-distance flight of the spring migration takes place. Here, we tested the hypothesis that the differential gene expressions observed in the brains of individuals captured in the autumn and spring windows are consistent with the previously described cellular changes. We searched for differential gene expressions in the brain of the semipalmated sandpiper, of recently arrived birds (RA) from the autumnal migration, and that of individuals in the premigratory period (PM) in the spring. All individuals were collected in the tropical coastal of northern Brazil in the mangrove region of the Amazon River estuary. We generated a de novo neurotranscriptome for C. pusilla individuals and compared the gene expressions across libraries. To that end, we mapped an RNA-Seq that reads to the C. pusilla neurotranscriptome in four brain samples of each group and found that the differential gene expressions in newly arrived and premigratory birds were related with neurogenesis, metabolic pathways (ketone body biosynthetic and the catabolic and lipid biosynthetic processes), and glial changes (astrocyte-dopaminergic neuron signaling, astrocyte differentiation, astrocyte cell migration, and astrocyte activation involved in immune response), as well as genes related to the immune response to virus infections (Type I Interferons), inflammatory cytokines (IL-6, IL-1β, TNF, and NF-κB), NLRP3 inflammasome, anti-inflammatory cytokines (IL-10), and cell death pathways (pyroptosis- and caspase-related changes)