Circulating miR-141-3p, miR-143-3p and miR-200c-3p are differentially expressed in colorectal cancer and advanced adenomas.

Colorectal cancer (CRC) is one of the prominent causes of cancer related deaths because, in part, there is not an early, non-invasive, effective detection strategy. Circulating microRNAs (miRNAs) have been proposed as potential non-invasive biomarkers for CRC. In this study, we evaluated the miRNA profile in sixteen CRC tissues by Next-Generation-Sequencing and compared the circulating expression levels of 22 miRNAs among 45 CRC, 14 hyperplastic polyps, 11 advanced adenoma patients and 45 control subjects, by reverse transcription-quantitative PCR, to search for miRNAs which could be potential biomarkers. In total, nine of them represented 70% of total read counts (miR-10a-5p, miR-192-5p, miR-10b-5p, miR-22-3p, miR-26a-5p, miR-148a-3p, miR-181a-5p, miR-92a-3p and miR-143-5p). In silico analysis found eight candidates to mature miRNAs. With respect to circulating miRNA, we found higher serum expression levels of miR-143-3p, miR-141-3p and miR-200c-3p in the CRC and adenoma groups compared with controls (P<0.002), and we also found significant higher levels of miR-141-3p and miR-200c-3p in serum of adenoma patients compared with the CRC group. In conclusion, the measurement of miRNAs in the blood could complement current screening methods for CRC and might provide new insights into mechanisms of tumorigenesis. miR-143-3p, miR-141-3p and miR-200c-3p could be interesting miRNAs to study as potential biomarkers for CRC.

E6 molecular variants of human papillomavirus (HPV) type 16: an updated and unified criterion for clustering and nomenclature.

Reports on taxonomic identification of E6/HPV 16 variants, don't have a worldwide, updated and unified criterion for clustering and nomenclature. Our aim was to update the existing criterion and propose a new one for clustering and nomenclature for E6/HPV 16 molecular variants based on the descriptive and comparative analyses of nucleotide sequences. A systematic search of the publications between 1991 and 2010 was carried out in PUBMED and manually. 240 E6/HPV 16 variants were identified. 157 were classified as European (E), 24 as Asian (As), 14 as Asian American (AA), 11 as North American 1 (NA 1), 19 as African 1 (Af 1) and 15 as African 2 (Af 2). Three classes were determined for the E, 3 each for the As, Af 2 and AA branches, 4 classes for the NA 1 and 6 for the Af 1 branch. This study reports our results and proposes an updated criterion for clustering and nomenclature that will be useful for E6 variant identification.

Consideraciones éticas y legales de los biobancos para investigación: [revisión] / Research biobanks: ethical and legal considerations: [review]

Un biobanco es una colección de muestras biológicas y datos asociados con fines diagnósticos, terapéuticos o de investigación. Las actividades llevadas a cabo por los bancos de muestras biológicas conllevan muchos dilemas éticos y legales, por lo que en el ámbito internacional existen diversas normas y recomendaciones establecidas para salvaguardar los derechos de los donantes. En Colombia, el Instituto Nacional de Cancerología considera prioritario la creación de un biobanco con fines de investigación. El propósito de este artículo es realizar una revisión de la literatura, internacional como nacional, sobre los aspectos éticos y legales relacionados con los biobancos para investigación científica. La adaptación de los requerimientos internacionales sería el primer paso para la implementación de los estándares éticos y legales de los biobancos en Colombia. Se hace necesario el establecimiento de regulaciones nacionales que controlen las actividades de dichos biobancos y de esta manera se contribuya a la participación activa de la sociedad colombiana.