[MicroRNAs and nonresolving inflammation-related cancer]

The Single-Nucleotide Polymorphism of miR-27a rs895819 and the Expression of miR-27a in Helicobacter pylori-Related Diseases and the Correlation with the Traditional Chinese Medicine Syndrome

Aims

The study aims to explore the effects of the single-nucleotide polymorphism of miR-27a and its expression in Helicobacter pylori (H. pylori)-related diseases and the relationship between gastric pathology and traditional Chinese medicine (TCM).

Methods

Subjects were classified into six histopathological groups and five TCM syndrome groups. All specimens underwent H. pylori detection through rapid urease test and methylene blue staining. Histopathological characteristics were observed by hematoxylin-eosin. The expression of miR-27a and its genotype were, respectively, detected by Quantitative Real-Time PCR and direct sequencing.

Results

H. pylori promoted the malignant evolution of gastric mucosa and were involved in the formation of TCM syndrome. In H. pylori-positive patients, the frequency of miR-27a CT genotype at the rs895819 locus and its expression in the gastric cancer group were higher than those in other pathological groups. TCM syndrome had a close relationship with histopathological changes, and patients with spleen-qi deficiency syndrome had a higher risk of gastric cancer than other syndromes, regardless of H. pylori infection.

Conclusion

The C allele at miR-27a rs895819 locus may be an oncogene in gastric cancer. High levels of miR-27a could play an important role in gastric malignant evolution, especially cancerization. There is a certain connection between TCM syndrome and pathological changes of the gastric mucosa to some extent, where patients with SQD syndrome had a higher risk of GC.

Impaired expression of DICER and some microRNAs in HBZ expressing cells from acute adult T-cell leukemia patients

Global dysregulation of microRNAs (miRNAs), a class of non-coding RNAs that regulate genes expression, is a common feature of human tumors. Profiling of cellular miRNAs on Adult T cell Leukemia (ATL) cells by Yamagishi et al. showed a strong decrease in expression for 96.7% of cellular miRNAs in ATL cells. However, the mechanisms that regulate the expression of miRNAs in ATL cells are still largely unknown. In this study, we compared the expression of 12 miRs previously described for being overexpress by Tax and the expression of several key components of the miRNAs biogenesis pathways in different HBZ expressing cell lines as well as in primary CD4 (+) cells from acute ATL patients. We showed that the expression of miRNAs and Dicer1 were downregulated in cells lines expressing HBZ as well as in fresh CD4 (+) cells from acute ATL patients. Using qRT-PCR, western blotting analysis and Chromatin Immunoprecipitation, we showed that dicer transcription was regulated by c-Jun and JunD, two AP-1 transcription factors. We also demonstrated that HBZ affects the expression of Dicer by removing JunD from the proximal promoter. Furthermore, we showed that at therapeutic concentration of 1mM, Valproate (VPA) an HDAC inhibitors often used in cancer treatment, rescue Dicer expression and miRNAs maturation. These results might offer a rationale for clinical studies of new combined therapy in an effort to improve the outcome of patients with acute ATL.

Post-transcriptional regulation in osteoblasts using localized delivery of miR-29a inhibitor from nanofibers to enhance extracellular matrix deposition

MicroRNAs are important post-transcriptional regulators of skeletal biology, and miRNA-based therapeutics have the potential to aid bone repair. However, efficient tools for delivering miRNA mimics or inhibitors to specific target tissues are limited. Polymeric nanofibers closely mimic natural extracellular matrix (ECM) morphology, and are attractive candidates for supporting delivery of cells and bone-anabolic reagents. It is hypothesized that gelatin nanofibers could be used for the localized transient delivery of miRNA-based therapeutics, using miR-29a inhibitor as a prototype to increase ECM deposition. miR-29 family members are negative regulators of ECM synthesis, targeting the mRNAs of selected collagens and osteonectin/SPARC. Inhibiting miR-29 activity may therefore increase ECM production by cells. miR-29a inhibitor-loaded gelatin nanofibers, prepared by electrospinning, demonstrated continuous release of miRNA inhibitor over 72h. Pre-osteoblastic murine MC3T3-E1 cell line seeded on miR-29a inhibitor-loaded nanofibers synthesized more osteonectin, indicating efficient inhibitor delivery. These cells also displayed increased Igf1 and Tgfb1 mRNA. Moreover, primary bone marrow stromal cells from transgenic pOBCol3.6cyan reporter mice, grown on miR-29a inhibitor scaffolds, displayed increased col3.6 cyan expression as well as collagen production. This study demonstrates that ECM mimicking nanostructured scaffolds, in conjunction with bioactive miRNA-based therapeutics, may serve as a novel platform for developing biologically active localized cell delivery systems.