Prostate cancer is a major health problem worldwide due to its high incidence morbidity and mortality. There is currently a need of improved biomarkers, capable to distinguish mild versus aggressive forms of the disease, and thus guide therapeutic decisions. Although miRNAs deregulated in cancer represent exciting candidates as biomarkers, its scientific literature is frequently fragmented in dispersed studies. This problem is aggravated for miRNAs belonging to miRNA gene clusters with shared target genes. The miRNA cluster composed by hsa-mir-130b and hsa-mir-301b precursors was recently involved in prostate cancer pathogenesis, yet different studies assigned it opposite effects on the disease. We sought to elucidate the role of the human miR-130b/301b miRNA cluster in prostate cancer through a comprehensive data analysis of most published clinical cohorts. We interrogated methylomes, transcriptomes and patient clinical data, unifying previous reports and adding original analysis using the largest available cohort (TCGA-PRAD). We found that hsa-miR-130b-3p and hsa-miR-301b-3p are upregulated in neoplastic vs normal prostate tissue, as well as in metastatic vs primary sites. However, this increase in expression is not due to a decrease of the global DNA methylation of the genes in prostate tissues, as the promoter of the gene remains lowly methylated in normal and neoplastic tissue. A comparison of the levels of human miR-130b/301b and all the clinical variables reported for the major available cohorts, yielded positive correlations with malignance, specifically significant for T-stage, residual tumor status and primary therapy outcome. The assessment of the correlations between the hsa-miR-130b-3p and hsa-miR-301b-3p and candidate target genes in clinical samples, supports their repression of tumor suppressor genes in prostate cancer. Altogether, these results favor an oncogenic role of miR-130b/301b cluster in prostate cancer.

Trypanosomatids are protozoan parasites that cause devastating vector-borne human diseases. Gene expression regulation of these organisms depends on post-transcriptional control in responding to diverse environments while going through multiple developmental stages of their complex life cycles. In this scenario, non-coding RNAs (ncRNAs) are excellent candidates for a very efficient, quick, and economic strategy to regulate gene expression. The advent of high throughput RNA sequencing technologies show the presence and deregulation of small RNA fragments derived from canonical ncRNAs. This review seeks to depict the ncRNA landscape in trypanosomatids, focusing on the small RNA fragments derived from functional RNA molecules observed in RNA sequencing studies. Small RNA fragments derived from canonical ncRNAs (tsRNAs, snsRNAs, sdRNAs, and sdrRNAs) were identified in trypanosomatids. Some of these RNAs display changes in their levels associated with different environments and developmental stages, demanding further studies to determine their functional characterization and potential roles. Nevertheless, a comprehensive and detailed ncRNA annotation for most trypanosomatid genomes is still needed, allowing better and more extensive comparative and functional studies.

Prostate cancer is a major health problem worldwide. MiR-183 is an oncomiR and a candidate biomarker in prostate cancer, affecting various pathways responsible for disease initiation and progression. We sought to discover the most relevant processes controlled by miR-183 through an unbiased transcriptomic approach using prostate cell lines and patient tissues to identify miR-183 responsive genes and pathways. Gain of function experiments, reporter gene assays, and transcript and protein measurements were conducted to validate predicted functional effects and protein mediators. A total of 135 candidate miR-183 target genes overrepresenting cell adhesion terms were inferred from the integrated transcriptomic analysis. Cell attachment, spreading assays and focal adhesion quantification of miR-183-overexpressing cells confirmed the predicted reduction in cell adhesion. ITGB1 was validated as a major target of repression by miR-183 as well as a mediator of cell adhesion in response to miR-183. The reporter gene assay and PAR-CLIP read mapping suggest that ITGB1 may be a direct target of miR-183. The negative correlation between miR-183 and ITGB1 expression in prostate cancer cohorts supports their interaction in the clinical set. Overall, cell adhesion was uncovered as a major pathway controlled by miR-183 in prostate cancer, and ITGB1 was identified as a relevant mediator of this effect.