Epigenetic alterations in canine mammary cancer.

In dogs, mammary cancer is the most common tumor type, especially in unspayed females. As in humans, this type of cancer has spontaneous development and is influenced by several risk factors, such as age and hormonal exposure in addition to genetic and epigenetic factors. Epigenetic mechanisms are responsible for gene expression modulation without alterations in the DNA sequence and include but are not limited to DNA methylation, histone modifications, and noncoding RNAs.

Mitochondrial DNA Alterations in Glioblastoma (GBM).

Glioblastoma (GBM) is an extremely aggressive tumor originating from neural stem cells of the central nervous system, which has high histopathological and genomic diversity. Mitochondria are cellular organelles associated with the regulation of cellular metabolism, redox signaling, energy generation, regulation of cell proliferation, and apoptosis. Accumulation of mutations in mitochondrial DNA (mtDNA) leads to mitochondrial dysfunction that plays an important role in GBM pathogenesis, favoring abnormal energy and reactive oxygen species production and resistance to apoptosis and to chemotherapeutic agents.

Pisosterol Induces G2/M Cell Cycle Arrest and Apoptosis via the ATM/ATR Signaling Pathway in Human Glioma Cells.

Background: Pisosterol, a triterpene derived from Pisolithus tinctorius, exhibits potential antitumor activity in various malignancies. However, the molecular mechanisms that mediate the pisosterol-specific effects on glioma cells remain unknown.

Objective: This study aimed to evaluate the antitumoral effects of pisosterol on glioma cell lines.

A new oligotrich (Ciliophora, Oligotrichia) from Argentina, with redefinition of Novistrombidium Song and Bradbury.

A new oligotrich similar to Novistrombidium was discovered in plankton samples from an artificial tributary of the Salado River, Buenos Aires province, Argentina, in summer 2010. Propecingulum fistoleramalliei sp. n.

Expression Pattern of and Its Regulators in Canine Mammary Tumors.

Background/aim: In female dogs, mammary cancer is the most frequent cancer type, accounting for 50% of all tumors affecting these animals. Amongst the commonly altered genes in cancer is the cell-cycle regulator cyclin-dependent kinase inhibitor 2B (Cdkn2b), whose expression is negatively regulated by protein products of BMI1 proto-oncogene (Bmi1), MYC proto-oncogene (Myc) and T-box gene transcription factor 2 (Tbx2) genes. Considering this, the aim of this study was to evaluate the expression pattern of the Cdkn2b gene and these regulators in canine mammary tumors of dogs from Northern Brazil (Belém, Pará).

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

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.

Frequency of the Loss of Heterozygosity of the Gene in Sporadic Spinal Schwannomas.

Background/aim: Individuals with type 2 Neurofibromatosis are predisposed for the appearance of schwannomas. In the present study we analyzed the loss of heterozygosity and mutations in the NF2 gene in patients with sporadic Schwannoma without Neurofibromatosis type 2.

Materials And Methods: We analyzed 39 patients with sporadic spinal schwannoma.

An update on the epigenetics of glioblastomas.

Glioblastomas, also known as glioblastoma multiforme (GBM), are the most aggressive and malignant type of primary brain tumor in adults, exhibiting notable variability at the histopathological, genetic and epigenetic levels. Recently, epigenetic alterations have emerged as a common hallmark of many tumors, including GBM. Considering that a deeper understanding of the epigenetic modifications that occur in GBM may increase the knowledge regarding the tumorigenesis, progression and recurrence of this disease, in this review we discuss the recent major advances in GBM epigenetics research involving histone modification, glioblastoma stem cells, DNA methylation, noncoding RNAs expression, including their main alterations and the use of epigenetic therapy as a valid option for GBM treatment.

Genotyping and prevalence of Chlamydia trachomatis infection among women in Belém, Pará, northern Brazil.

Introduction: Genital Chlamydia trachomatis infection is one of the most prevalent sexually transmitted diseases in women, and undetected cases of the disease are highly associated with long-term complications. Despite the high prevalence of infections in Brazil, very little is known about the distribution of C. trachomatis genovars.

Deregulated Expression of SRC, LYN and CKB Kinases by DNA Methylation and Its Potential Role in Gastric Cancer Invasiveness and Metastasis.

Kinases are downstream modulators and effectors of several cellular signaling cascades and play key roles in the development of neoplastic disease. In this study, we aimed to evaluate SRC, LYN and CKB protein and mRNA expression, as well as their promoter methylation, in gastric cancer. We found elevated expression of SRC and LYN kinase mRNA and protein but decreased levels of CKB kinase, alterations that may have a role in the invasiveness and metastasis of gastric tumors.

Description and Phylogeny of Urostyla grandis wiackowskii subsp. nov. (Ciliophora, Hypotricha) from an Estuarine Mangrove in Brazil.

Interphase specimens, aspects of physiological reorganization and divisional morphogenesis were investigated in a strain of a hypotrichous ciliate highly similar to Urostyla grandis Ehrenberg, (type species of Urostyla), collected from a mangrove area in the estuary of the Paraíba do Sul river (Rio de Janeiro, Brazil). The results revealed that albeit interphase specimens match with the known morphologic variability in U. grandis, morphogenetic processes have conspicuous differences.

Expression Analysis of Genes Involved in the RB/E2F Pathway in Astrocytic Tumors.

Astrocytic gliomas, which are derived from glial cells, are considered the most common primary neoplasias of the central nervous system (CNS) and are histologically classified as low grade (I and II) or high grade (III and IV). Recent studies have shown that astrocytoma formation is the result of the deregulation of several pathways, including the RB/E2F pathway, which is commonly deregulated in various human cancers via genetic or epigenetic mechanisms. On the basis of the assumption that the study of the mechanisms controlling the INK4/ARF locus can help elucidate the molecular pathogenesis of astrocytic tumors, identify diagnostic and prognostic markers, and help select appropriate clinical treatments, the present study aimed to evaluate and compare methylation patterns using bisulfite sequencing PCR and evaluate the gene expression profile using real-time PCR in the genes CDKN2A, CDKN2B, CDC6, Bmi-1, CCND1, and RB1 in astrocytic tumors.

Fine Structure and Molecular Phylogeny of Parametopidium circumlabens (Ciliophora: Armophorea), Endocommensal of Sea Urchins.

Metopid armophoreans are ciliates commonly found in anaerobic environments worldwide; however, very little is known of their fine structure. In this study, the metopid Parametopidium circumlabens (Biggar and Wenrich 1932) Aescht, 1980, a common endocommensal of sea urchins, is investigated for the first time with emphasis on transmission electron microscopy, revealing several previously unknown elements of its morphology. Somatic dikinetids of P.

Perspectives on new biomarkers in gastric cancer: diagnostic and prognostic applications.

Gastric cancer is considered one of the most deadly tumors worldwide. Even with the decline in its incidence, the mortality rate of this disease has remained high, mainly due to its late diagnosis and to the lack of precise prognostic markers. The main purpose of this review is to present genetic, epigenetic and proteomic molecular markers that may be used in a diagnostic and prognostic manner and to discuss the pros and cons of each type of marker for improving clinical practice.

Deregulation of MYC and TP53 through genetic and epigenetic alterations in gallbladder carcinomas.

Gallbladder cancer is a rare malignancy and presents a poor prognosis. MYC and p53 have been implicated in gallbladder carcinogenesis. However, little is known about the molecular mechanisms involved in their regulation in this neoplasia.

Genetic screening analysis of patients with hereditary diffuse gastric cancer from northern and northeastern Brazil.

Background: Hereditary diffuse gastric cancer (HDGC) is a hereditary autosomal inherited syndrome associated with CDH1 germline mutations. In Brazil, gastrointestinal tumors are among the most prevalent tumor types and constitute a serious public health problem, especially in the northern and northeastern regions. This study aimed to investigate germline mutations, methylation pattern and genomic rearrangements in the CDH1 gene and quantitative changes in the DNA of HDGC patients in northern and northeastern Brazil.

Description and phylogeny of Tetrakeronopsis silvanetoi gen. nov., sp. nov. (Hypotricha, Pseudokeronopsidae), a new benthic marine ciliate from Brazil.

Pseudokeronopsidae Borror & Wicklow, 1983 are biotechnologically important ciliate protists which produce toxic defense substances; however, their diversity is still little known in Brazil. In the present study, Tetrakeronopsis silvanetoi, a new genus and species of marine pseudokeronopsid hypotrichs is described from samples of water with bottom sediment collected from the coast of São Paulo state. Its phylogenetic affinities to the "core urostyloids" are hypothesized based on analyses of the 18S-rDNA marker, and a new subfamily, the Nothoholostichinae subfam.

Phylogenetic study of Class Armophorea (Alveolata, Ciliophora) based on 18S-rDNA data.

The 18S rDNA phylogeny of Class Armophorea, a group of anaerobic ciliates, is proposed based on an analysis of 44 sequences (out of 195) retrieved from the NCBI/GenBank database. Emphasis was placed on the use of two nucleotide alignment criteria that involved variation in the gap-opening and gap-extension parameters and the use of rRNA secondary structure to orientate multiple-alignment. A sensitivity analysis of 76 data sets was run to assess the effect of variations in indel parameters on tree topologies.

Phylogeography of the dark fruit-eating bat Artibeus obscurus in the Brazilian Amazon.

Artibeus obscurus (Mammalia: Chiroptera) is endemic to South America, being found in at least 18 Brazilian states. Recent studies revealed that different populations of this genus present distinct phylogeographic patterns; however, very little is known on the population genetics structure of A. obscurus in the Amazon rainforest.

MYC deregulation in gastric cancer and its clinicopathological implications.

Our study investigated the relationship between MYC alterations and clinicopathological features in gastric cancers. We evaluated the effect of MYC mRNA expression and its protein immunoreactivity, as well as copy number variation, promoter DNA methylation, and point mutations, in 125 gastric adenocarcinoma and 67 paried non-neoplastic tissues. We observed that 77% of the tumors presented MYC immunoreactivity which was significantly associated with increased mRNA expression (p<0.

Analysis of the methylation patterns of the p16 INK4A, p15 INK4B, and APC genes in gastric adenocarcinoma patients from a Brazilian population.

Gastric cancer is a major public health problem in Pará state, where studies suggest complex genetic and epigenetic profiles of the population, indicating the need for the identification of molecular markers for this tumor type. In the present study, the methylation patterns of three genes [p16 (INK4A), p15 (INK4B), and adenomatous polyposis coli (APC)] were assessed in patients with gastric adenocarcinoma from Pará state in order to identify possible molecular markers of gastric carcinogenesis. DNA samples from tumoral and non-tumoral gastric tissues were modified with sodium bisulfite.

An Antarctic hypotrichous ciliate, Parasterkiella thompsoni (Foissner) nov. gen., nov. comb., recorded in Argentinean peat-bogs: morphology, morphogenesis, and molecular phylogeny.

The ciliate Parasterkiella thompsoni (Foissner, 1996) nov. gen., nov.

Morphology and 18S rDNA phylogeny of Hemicycliostyla sphagni (Ciliophora, Hypotricha) from Brazil with redefinition of the genus Hemicycliostyla.

Morphology of the urostylid ciliate Hemicycliostyla sphagni Stokes, 1886, the type of Hemicycliostyla Stokes, 1886, is investigated based on live and protargol-impregnated specimens from a Brazilian population. The absence of transverse cirri, which has been considered the main diagnostic feature of Hemicycliostyla, separating it from Pseudourostyla Borror, 1972, was found to vary within the studied population, with 50% of the specimens exhibiting inconspicuous and/or rudimentary transverse cirri. A redefinition of Hemicycliostyla was possible based on combined features of interphase and divisional morphogenesis: Retroextendia Berger, 2006, with bi- or multicoronal frontal cirral pattern; fronto-terminal cirri present; multiple left and right marginal cirral rows that replicate independently via within-row development, each parental row producing one primordium per divider; caudal cirri lacking; and presence/absence of transverse cirri may be intrapopulationally variable.

Survivin -31C/G polymorphism and gastric cancer risk in a Brazilian population.

Gastric cancer, despite its decline in incidence, remains a public health problem worldwide, especially in Brazil, where higher incidence indexes are still described. The Survivin gene codifies a multifunctional protein involved in the regulation of the cell cycle and inhibition of the apoptotic pathway, and a polymorphism (-31C/G) located in its promoter region is associated with gene regulation. In order to evaluate the correlation of this polymorphism with gastric cancer risk in a northern Brazil population, we sequenced a fragment containing the polymorphism in individuals with gastric cancer and controls.

Absence of CIP1/KIP1 hypermethylation in gastric cancer patients from Northern Brazil.

Unlabelled: The aim of this study was to investigate the protein expression and methylation pattern of P21(CIP1) and P27(KIP1) genes.

Patients And Methods: Twenty samples of gastric tumor and non-tumoral tissues of patients from Pará state, Brazil were collected. Methylation patterns were assessed by bisulfite sequencing, and protein expression evaluated with immunohistochemical analysis.