Approaches to the modulation of miRNA maturation

Gentamycin Rationally Repositioned to Inhibit miR-34a Ameliorates Oxidative Injury to PC12 Cells

Ischemic stroke accompanies oxidative stress and cell death in the cerebral tissue. The microRNA miR-34a plays a pivotal role in this molecular pathology. This study presents the rational repositioning of aminoglycosidic antibiotics as miR-34a antagonists in order to assess their efficiency in protecting the PC12 stroke model cells from oxidative stress occurring under cerebral ischemic conditions. A library of 29 amino-sugar compounds were screened against anticipated structural models of miR-34a through molecular docking. MiR-ligand interactions were mechanistically studied by molecular dynamics simulations and free-energy calculations. Cultured PC12 cells were treated by H₂O₂ alone or in combination with gentamycin and neomycin as selected drugs. Cell viability and apoptosis were detected by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) and annexin V-FITC/propidium iodate (PI) double staining assays, respectively. The expression levels of key factors involved in cell proliferation, oxidative stress, and apoptosis in treated PC12 cells were measured through a quantitative real-time polymerase chain reaction and flow cytometric annexin V-FITC/PI double staining assays. A stable and energetically favorable binding was observed for miR-34a with gentamycin and neomycin. Gentamycin pretreatments followed by H₂O₂ oxidative injury led to increased cell viability and protected PC12 cells against H₂O₂-induced apoptotic events. This study will help in further understanding how the suppression of miR-34a in neural tissue affects the cell viability upon stroke.

MiRNA-873-5p Acts as a Potential Novel Biomarker and Promotes Cervical Cancer Progression by Regulating ZEB1 via Notch Signaling Pathway

OBJECTIVE

Our group aimed to investigate the expression pattern of miRNA-873-5p in cervical cancer (CC) patients and its association with CC progression.

METHODS

Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was applied for the examination of the expressions of miRNA-873-5p in both CC specimens and cell lines. The clinical significance of miRNA-873-5p was statistically analyzed. MTT, colony formation, Transwell and flow cytometry assays were used to detect cell proliferation, metastasis, and apoptosis changes of Hela and Siha cell line. Luciferase reporter assays and Western blots were utilized to identify the target genes of miRNA-873-5p. Western blot and RT-PCR were used to judge the dysregulation of Notch signaling.

RESULTS

Our results indicated that miRNA-873-5p expression was distinctly reduced in CC patients. Low miRNA-873-5p expressions were distinctly correlated with positively distant metastasis, The International Federation of Gynecology and Obstetrics (FIGO) stage and poor prognosis of CC patients. A functional assay using miRNA-873-5p mimics indicated that overexpression of miRNA-873-5p distinctly suppressed CC cells proliferation and metastasis, and promoted apoptosis. Bioinformatic assays revealed that miRNA-873-5p may target the 3'-UTR of ZEB1 and lead to the suppression of its translation, which was verified by the use of luciferase assays. Finally, overexpression of miRNA-873-5p suppressed the expressions of Jag1, Maml2 and Hey1.

CONCLUSION

Taken together, we firstly provided evidence that miRNA-873-5p expression was a poor favorable factor for CC patients, and the use of miRNA-873-5p may represent a and potential biomarker and promising therapeutic approach for CC.