Effects of miR-18a on proliferation and apoptosis of gastric cancer cells by regulating RUNX1.

OBJECTIVE: The aim of this study was to explore the effects of micro ribonucleic acid (miR)-18a on the proliferation and apoptosis of gastric cancer (GC) cells, and to elucidate the possible underlying mechanism. PATIENTS AND METHODS: In this study, the expression of miR-18a in GC tissues and para-cancer tissues was verified by in situ hybridization (ISH) of GC tissue microarray (TMA). Meanwhile, the effect of miR-18a expression on the prognosis of GC patients was evaluated. GC AGS cell line was selected and transfected with miR-18a mimic and mimic control (NC) to up-regulate miR-18a expression in vitro. Thereafter, changes in cell proliferation, apoptosis and migration after transfection were detected by biological functional assays. Luciferase reporter gene assay was carried out to verify the target gene Runt-related transcription factor 1 (RUNX1) modulated by miR-18a. Finally, the Spearman's grade correlation coefficient was calculated to explore the correlation between the expressions of miR-18a and RUNX1. RESULTS: ISH results of TMA showed that overexpression of miR-18a in GC tissues was significantly associated with low survival rate of patients (p<0.001). High expression of miR-18a remarkably enhanced the proliferation, migration and invasion of GC cells (p<0.05). Besides, it has been predicted in biology that RUNX1 is one of the target genes of miR-18a. Luciferase reporter gene assay showed that Luciferase activity in cells transfected with wild-type (WT) RUNX1 3' untranslated region (3'UTR) was significantly reduced (p<0.05). Moreover, the protein expression of RUNX1 decreased remarkably in GC cells with over-expression of miR-18a (p<0.05). All these findings indicated that the expression of miR-18a was negatively correlated with RUNX1 in GC cells (p<0.001, r=0.86). CONCLUSIONS: MiR-18a exerts a high predictive value for the prognosis of GC patients by directly targeting the transcription factor RUNX1. All our findings may provide therapeutic candidates for GC identification.

LncRNA HMGA1P4 promotes cisplatin-resistance in gastric cancer.

OBJECTIVE: Long non-coding RNA (lncRNA) HMGA1P4 has been previously reported to be upregulated in gastric cancer (GC). This study aims to investigate the role of HMGA1P4 in cisplatin (DDP)-resistant GC. PATIENTS AND METHODS: HMGA1P4 levels in DDP-resistant GC tissues and cells were determined. Regulatory effects of HMGA1P4 on proliferative and apoptotic abilities in DDP-resistant GC cells and their parental cells were assessed. At last, expression levels of genes associated with multidrug-resistance (MDR) (MDR1, MRP1, mTOR and HIF-1α) and apoptosis (Bax, Bcl-2 and Caspase3) were determined in DDP-resistant GC cells. RESULTS: Results revealed that HMGA1P4 was upregulated in DDP-resistant GC tissues and cells. Overexpression of HMGA1P4 stimulated proliferative rate and suppressed apoptosis in both DDP-resistant GC cells and their parental cells. Moreover, in DDP-resistant GC cells, overexpression of HMGA1P4 upregulated MDR-related genes and downregulated apoptosis-related genes. CONCLUSIONS: HMGA1P4 is upregulated in DDP-resistant GC tissues and cells, and triggers the progression of DDP-resistance in GC.

Origin of ultralow Young׳s modulus in a metastable ß-type Ti-33Nb-4Sn alloy.

Although there is difficulty in growing a Ti-33Nb-4Sn single crystal due to its ultralow ß-phase stability, the single-crystal elastic constants of metastable ß-type Ti-33Nb-4Sn (wt%) alloy were extracted successfully from its polycrystal by in-situ synchrotron X-ray diffraction technique, to clarify the origin of the ultralow Young's modulus in its polycrystal. It is indicated that compared to binary TiCr, TiV and TiNb alloys, the Ti-33Nb-4Sn alloy possesses slightly lower ß-phase stability with respect to {110}<110>(-)shear (i.e., C׳) but much lower ß-phase stability regarding to {001}〈100〉 shear (i.e., C44). An analysis by the Hill approximation suggests that the ultralow isotropic polycrystalline Young׳s modulus (EH) of Ti-33Nb-4Sn alloy originates from the extremely low shear modulus C44 as well as the relatively low C׳. This indicates that in addition to C׳, C44 has a significant contribution to the Young's modulus of polycrystal, which challenges a conventional understanding that the Young's modulus of ß-type Ti alloys is predominantly determined by C׳.

Removal of organic compounds during treating printing and dyeing wastewater of different process units.

Wastewater in Shaoxing wastewater treatment plant (SWWTP) is composed of more than 90% dyeing and printing wastewater with high pH and sulfate. Through a combination process of anaerobic acidogenic [hydraulic retention time (HRT) of 15h], aerobic (HRT of 20h) and flocculation-precipitation, the total COD removal efficiency was up to 91%. But COD removal efficiency in anaerobic acidogenic unit was only 4%. As a comparison, the COD removal efficiency was up to 35% in the pilot-scale upflow anaerobic sludge bed (UASB) reactor (HRT of 15h). GC-MS analysis showed that the response abundance of these wastewater samples decreased with their removal of COD. A main component of the raw influent was long-chain n-alkanes. The final effluent of SWWTP had only four types of alkanes. After anaerobic unit at SWWTP, the mass percentage of total alkanes to total organic compounds was slightly decreased while its categories increased. But in the UASB, alkanes categories could be removed by 75%. Caffeine as a chemical marker could be detected only in the effluent of the aerobic process. Quantitative analysis was given. These results demonstrated that GC-MS analysis could provide an insight to the measurement of organic compounds removal.

Performance of anaerobic process on toxicity reduction during treating printing and dyeing wastewater.

The paper was to evaluate anaerobic treatment efficiency of reducing toxic compounds by gas chromatography mass spectrometry (GC-MS) analysis combined with biological toxicity test during the treatment process of printing and dyeing wastewater. There had an obvious decrease trend in the response abundance of GC-MS chromatograms between raw influent and anaerobic effluents with the removal of COD. A main component of the raw effluent was long-chain n-alkanes. Alkanes in the expanded granular sludge bed (EGSB) categories could be reduced by 75%. EGSB had a better degradation performance on some complicated pollutants and toxicity. The most sensitive bioassay was Microtox bioassay.

Comparison of subcooled liquid vapor pressures of polychlorinated dibenzo-p-dioxins and dibenzofurans predicted by QSPR and GC-RI methods.

Subcooled liquid vapor pressures (P(L)) are of great importance for assessing the persistent behavior of organic pollutants. As P(L) cannot be determined by direct experiments, it is of interest to develop and evaluate various predictive methods. In the current study, gas chromatography retention index (GC-RI) and quantitative structure-property relationship (QSPR) methods were used to develop predictive models for P(L) of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). The model development was based on P(L) values converted from consistent experimental solid vapor pressures (P(S)). The P(L) values predicted by the two methods are highly consistent with each other, and in-between sets of values predicted by others. Since the QSPR method can be regarded as independent of experiments, and can be used to interpret intermolecular interactions that govern the magnitude of P(L), it may be superior to the GC-RI method.

Chemical speciation and extractability of Zn, Cu and Cd in two contrasting biosolids-amended clay soils.

An incubation experiment was conducted to study the chemical speciation and extractability of three heavy metals in two contrasting biosolids-amended clay soils. One was a paddy soil of pH 7.8 and the other was a red soil of pH 4.7 collected from a fallow field. Anaerobically digested biosolids were mixed with each of the two soils at three rates: 20, 40 and 60 g kg(-1) soil (DM basis), and unamended controls were also prepared. The biosolids-amended and control soils were incubated at 70% of water holding capacity at 25 degrees C for 50 days. Separate subsamples were extracted with three single extractants and a three-step sequential extraction procedure representing acetic acid (HOAc)-soluble, reducible and oxidisable fractions to investigate the extractability and speciation of the heavy metals. As would be expected, there were good relationships between biosolids application rate and metal concentrations in the biosolids-amended soils. The three heavy metals had different extractabilities and chemical speciation in the two biosolids-amended soils. Ethylene diamine tetraacetic acid extracted more Cu, Zn and Cd than did the other two single extractants. The oxidisable fraction was the major fraction for Cu in both biosolids-amended soils and the HOAc-soluble and reducible fractions accounted for most of the Zn. In contrast, Cd was present mainly in the reducible fraction. The results are discussed in relation to the mobility and bioavailability of the metals in polluted soils.