Exploring the Genetic Diversity of Epstein-Barr Virus among Patients with Gastric Cancer in Southern Chile.

The Epstein-Barr virus (EBV) has been associated with gastric cancer (GC), one of the deadliest malignancies in Chile and the world. Little is known about Chilean EBV strains. This study aims to investigate the frequency and genetic diversity of EBV in GC in patients in southern Chile. To evaluate the prevalence of EBV in GC patients from the Chilean population, we studied 54 GC samples using the gold standard detection method of EBV-encoded small RNA (EBER). The EBV-positive samples were subjected to amplification and sequencing of the Epstein-Barr virus nuclear protein 3A (EBNA3A) gene to evaluate the genetic diversity of EBV strains circulating in southern Chile. In total, 22.2% of the GC samples were EBV-positive and significantly associated with diffuse-type histology (p = 0.003). Phylogenetic analyses identified EBV-1 and EBV-2 in the GC samples, showing genetic diversity among Chilean isolates. This work provides important information for an epidemiological follow-up of the different EBV subtypes that may cause GC in southern Chile.

Temperature Differentially Affects Gene Expression in Antarctic Thraustochytrid Oblongichytrium sp. RT2316-13.

Oblongichytrium RT2316-13 synthesizes lipids rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The content of these fatty acids in the total lipids depended on growth temperature. Sequencing technology was used in this work to examine the thraustochytrid's response to a decrease in growth temperature from 15 °C to 5 °C. Around 4% (2944) of the genes were differentially expressed (DE) and only a few of the DE genes (533 upregulated; 206 downregulated) had significant matches to those in the SwissProt database. Most of the annotated DE genes were related to cell membrane composition (fatty acids, sterols, phosphatidylinositol), the membrane enzymes linked to cell energetics, and membrane structure (cytoskeletal proteins and enzymes). In RT2316-13, the synthesis of long-chain polyunsaturated fatty acids occurred through ω3- and ω6-pathways. Enzymes of the alternative pathways (Δ8-desaturase and Δ9-elongase) were also expressed. The upregulation of the genes coding for a Δ5-desaturase and a Δ5-elongase involved in the synthesis of EPA and DHA, explained the enrichment of total lipid with these two long-chain fatty acids at the low temperature. This molecular response has the potential to be used for producing microbial lipids with a fatty acids profile similar to that of fish oils.

Frequency of Human papillomavirus in women attending cervical cancer screening program in Chile.

BACKGROUND: Human papillomavirus (HPV) is the etiological factor for cervical cancer and its precursor lesions. The characterization of HPV genotypes in preneoplastic lesions and cervical cancer could establishes the effectiveness of vaccination plan in Chilean population. The aim of this study was to determine HPV frequency in a group of women including in a cervical screening program in the public health care system in Chile. METHODS: We analyzed 985 cervical smears samples from women with different histological diagnosis, attending to public health care in Temuco-Chile between 2004 and 2012, to detect HPV genotypes, through PCR followed by reverse line blotting assay. RESULTS: HPV was found present in 80.8% (n = 796) of samples. Only a 5.6% of 985 samples were infected with a low-risk HPV, considering multiple infections. 10.5% (n = 8/76) of normal cervical epithelia, 83.5% (n = 208/249) and 87.6% (n = 557/636) of low and high grade squamous intraepithelial lesions, respectively, and 95.8% (n = 23/24) of squamous cervical carcinomas tested positive for HPV. HPV 16 was the most frequent genotype found (Overall 44.9%, n = 442/985; SCC: 62.5%, n = 15/24). A high variability of HPV types was also found in preneoplastic lesions, whereas there was a selection of genotypes in neoplasia. Also, there was a higher risk of infection with HPV 16 in women ≤26 years and 34-41 years old (p < 0.05), meanwhile infections with HPV 16 or HPV 18 have related with cancer development (p < 0.01). CONCLUSIONS: These data provide further information about the frequency of HPV genotypes in women with cervical lesions in Chile, and the introduction of new targeted vaccines against a wider spectrum of HPV is suggested.

Epigenetic modulation of cytokine expression in gastric cancer: influence on angiogenesis, metastasis and chemoresistance.

Cytokines are proteins that act in the immune response and inflammation and have been associated with the development of some types of cancer, such as gastric cancer (GC). GC is a malignant neoplasm that ranks fifth in incidence and third in cancer-related mortality worldwide, making it a major public health issue. Recent studies have focused on the role these cytokines may play in GC associated with angiogenesis, metastasis, and chemoresistance, which are key factors that can affect carcinogenesis and tumor progression, quality, and patient survival. These inflammatory mediators can be regulated by epigenetic modifications such as DNA methylation, histone protein modification, and non-coding RNA, which results in the silencing or overexpression of key genes in GC, presenting different targets of action, either direct or mediated by modifications in key genes of cytokine-related signaling pathways. This review seeks insight into the relationship between cytokine-associated epigenetic regulation and its potential effects on the different stages of development and chemoresistance in GC.

Cellular FLICE-like inhibitory protein long form (c-FLIPL) overexpression is related to cervical cancer progression.

Cervical cancer is a leading cause of cancer deaths in women worldwide and infection by high-risk human papillomavirus types is a precursor event. The cellular FLICE-like inhibitory protein (c-FLIP) has been found to be overexpressed in several types of cancers and could be associated with cervical cancer progression because of its ability to inhibit the apoptotic process. To detect c-FLIP expression in cervical cancer, an immunohistochemical staining was performed, using tissue microarrays, on a series of 536 archival biopsy samples, including normal cervical tissues, low-grade and high-grade squamous intraepithelial lesions, and squamous cervical carcinomas. The epithelium in the normal cervix and low-grade squamous intraepithelial lesions mainly stained negatively for c-FLIP, whereas high-grade intraepithelial lesions and cancer samples showed an elevated expression of c-FLIP. A direct association was observed between the increasing grade of the lesion and the intensity of c-FLIP staining, in which the frequency of intense c-FLIP expression increased from 12.5% in the normal tissue to 82.1% in the cervical cancer tissue. An increased expression of c-FLIP may be an important factor in the progression of cervical cancer. This finding could aid in identifying patients with preneoplastic lesions at greater risk of developing cervical cancer. c-FLIP expression in cervical tissue may be a potential cervical cancer progression marker.

Novel Methylation Biomarkers for Colorectal Cancer Prognosis.

Colorectal cancer (CRC) comprises the third most common cancer worldwide and the second regarding number of deaths. In order to make a correct and early diagnosis to predict metastasis formation, biomarkers are an important tool. Although there are multiple signaling pathways associated with cancer progression, the most recognized are the MAPK pathway, p53 pathway, and TGF-ß pathway. These pathways regulate many important functions in the cell, such as cell cycle regulation, proliferation, differentiation, and metastasis formation, among others. Changes in expression in genes belonging to these pathways are drivers of carcinogenesis. Often these expression changes are caused by mutations; however, epigenetic changes, such as DNA methylation, are increasingly acknowledged to play a role in the deregulation of oncogenic genes. This makes DNA methylation changes an interesting biomarkers in cancer. Among the newly identified biomarkers for CRC metastasis INHBB, SMOC2, BDNF, and TBRG4 are included, all of which are highly deregulated by methylation and closely associated with metastasis. The identification of such biomarkers in metastasis of CRC may allow a better treatment and early identification of cancer formation in order to perform better diagnostics and improve the life expectancy.

Pansinusitis aguda odontogénica en adolescente: Reporte de caso / Acute odontogenic pansinusitis in adolescent: Case report

RESUMEN: La Pansinusitis aguda odontogénica es un cuadro infeccioso infrecuente que afecta a todos los senos paranasales, en el cual se hace necesario un diagnóstico precoz para obtener una menor morbilidad. Un correcto diagnóstico requiere una evaluación dental exhaustiva, apoyándose con imágenes apropiadas. El presente caso clínico reporta paciente femenino de 17 años, sin enfermedades crónicas de base, diagnosticada con pansinusitis aguda odontogénica a través de examen de tomografía axial computarizada. Fue manejada de forma intrahospitalaria con un equipo multidisciplinario para su recuperación. Tratada con antibioterapia de amplio espectro vía parenteral y manejo del dolor, posterior al alta médica se realizó endodoncia del diente afectado y rehabilitación con prótesis fija unitaria.

ABSTRACT: Acute Odontogenic Pansinusitis is an infrequent infectious disease that affects all the paranasal sinuses. It requires an early diagnosis to obtain a lower morbidity. A correct diagnosis requires thorough dental evaluation, supported by appropriate images. The present clinical case reports a 17-year-old female patient, without chronic underlying diseases, with anacute Odontogenic Pansinusitis diagnosed through a computerized axial tomography scan. She was treated by a multidisciplinary team for recovery, through parenteral wide spectrum antibiotic therapy and pain management. After medical discharge, root canal of the affected tooth and rehabilitation with fixed unitary prosthesis were performed.