miR-22-3p Suppresses Cell Proliferation and Migration of Gastric Cancer by Targeting ENO1.

Background and Objective: miR-22-3p functions as a tumor suppressor by targeting a variety of downstream genes, while its role and downstream targets in gastric cancer (GC) remain to be determined. We aimed to explore the role of miR-22-3p in gastric cancer and the potential mechanism. Methods: miR-22-3p mimic and inhibitor were used to overexpress or knockdown the expression of miR-22-3p separately. Quantitative real-time PCR (RT-qPCR) and Western blot were used to analyse the abundance of mRNA or protein level respectively. CCK-8 assay, cell colony formation assay, and flow cytometry were implemented to investigate the effect of miR-22-3p on gastric cancer cell proliferation and apoptosis. Luciferase assay was used to evaluate the role of miR-22-3p on the expression of glycolytic enzyme enolase 1 (ENO1). Results: In this study, we found that miR-22-3p was downregulated in GC cells. By transfecting the cells with miR-22-3p inhibitors or mimics, we showed that miR-22-3p suppressed GC cell proliferation and migration, as well as triggered cell death. In addition, we discovered that miR-22-3p was engaged in glycolysis by controlling the generation of lactate as well as the consumption of glucose. TargetScan database suggested that the ENO1 may be a target of the miR-22-3p, and the luciferase experiment verified this hypothesis. Recovery assays showed that the proliferation and migration of GC cells suppressed by miR-22-3p could be rescued by overexpression of ENO1. Conclusion: Collectively, we identified a new axis of miR-22-3p/ENO1 for GC development, which could be investigated as a therapeutic target for GC.

An "off-on-enhanced on" electrochemiluminescence biosensor based on resonance energy transfer and surface plasmon coupled 3D DNA walker for ultra-sensitive detection of microRNA-21.

In this study, a novel electrochemiluminescence (ECL) biosensor was developed to detect microRNA-21 (miRNA-21) with high sensitivity by leveraging the combined mechanisms of resonance energy transfer (RET) and surface plasmon coupling (SPC). Initially, the glassy carbon electrode (GCE) were coated with Cu-Zn-In-S quantum dots (CZIS QDs), known for their defect-related emission suitable for ECL sensing. Subsequently, a hairpin DNA H3 with gold nanoparticles (Au NPs) attached at the end was modified over the surface of the quantum dots. The Au NPs could effectively quench the ECL signals of CZIS QDs via RET. Further, a significant amount of report DNA was generated through the action of a 3D DNA walker. When the report DNA opened H3-Au NPs, the hairpin structure experienced a conformational change to a linear shape, increasing the gap between the CZIS QDs and the Au NPs. Consequently, the localized surface plasmon resonance ECL (LSPR-ECL) effect replaced ECL resonance energy transfer (ECL-RET). Moreover, the report DNA was released following the addition of H4-Au NPs, resulting in the formation of Au dimers and a surface plasma-coupled ECL (SPC-ECL) effect that enhanced the ECL intensity to 6.97-fold. The integration of new ECL-RET and SPC-ECL biosensor accurately quantified miRNA-21 concentrations from 10-8 M to 10-16 M with a limit of detection (LOD) of 0.08 fM, as well as successfully applied to validate human serum samples.

Effects of human opiorphin on food intake and water intake in mice following central administration.

Human opiorphin plays an important pharmacological functions in rats or mice. The present study was performed to investigate effects and underlying mechanism of central injected opiorphin on food intake and water intake in mice. Intracerebroventricularly (i.c.v.) administered opiorphin (5-20µg/kg) dose-dependently suppressed food intake in fasted mice, but had no influence on food intake in freely feeding mice. The cumulative food intake was significantly decreased at 60min after injection of 10 and 20µg/kg opiorphin and the food intake was significantly reduced during the 20-60min period after treatment. Non-selected opiate receptor antagonist naloxone could fully block the inhibitory effect induced by opiorphin on cumulative food intake at 60min in fasted mice, suggesting that the anorexic effect of opiorphin was related to the opioid system. Moreover, the anorexic effect induced by opiorphin in fasted mice was also significantly inhibited by pretreatment with captopril or valsartan, which suggested that endogenous angiotensin may be involved in the response to opiorphin. Interestingly, the effect of opiorphin on water intake was increased in both fasted and freely feeding mice, which was completely blocked by captopril and valsartan. Furthermore, naloxone did not modify the effect of opiorphin on water intake. All together, the food and water intake effects of opiorphin may be due to the protection of the endogenous angiotensin and opioid peptides from degradation by NEP or APN.

Changes of the Bacterial Abundance and Communities in Shallow Ice Cores from Dunde and Muztagata Glaciers, Western China.

In this study, six bacterial community structures were analyzed from the Dunde ice core (9.5-m-long) using 16S rRNA gene cloning library technology. Compared to the Muztagata mountain ice core (37-m-long), the Dunde ice core has different dominant community structures, with five genus-related groups Blastococcus sp./Propionibacterium, Cryobacterium-related., Flavobacterium sp., Pedobacter sp., and Polaromas sp. that are frequently found in the six tested ice layers from 1990 to 2000. Live and total microbial density patterns were examined and related to the dynamics of physical-chemical parameters, mineral particle concentrations, and stable isotopic ratios in the precipitations collected from both Muztagata and Dunde ice cores. The Muztagata ice core revealed seasonal response patterns for both live and total cell density, with high cell density occurring in the warming spring and summer months indicated by the proxy value of the stable isotopic ratios. Seasonal analysis of live cell density for the Dunde ice core was not successful due to the limitations of sampling resolution. Both ice cores showed that the cell density peaks were frequently associated with high concentrations of particles. A comparison of microbial communities in the Dunde and Muztagata glaciers showed that similar taxonomic members exist in the related ice cores, but the composition of the prevalent genus-related groups is largely different between the two geographically different glaciers. This indicates that the micro-biogeography associated with geographic differences was mainly influenced by a few dominant taxonomic groups.