LncRNA NEAT1 regulates proliferation, apoptosis and invasion of liver cancer

OBJECTIVE

The occurrence and progression of hepatocellular carcinoma (HCC) is a multi-step complex process and the exact molecular mechanisms remain to be elucidated. LncRNA NEAT1 is involved in tumorigenesis and progression. However, the role of LncRNA NEAT1 in HCC remains unclear.

PATIENTS AND METHODS

The tumor tissues and adjacent tissues of HCC patients were collected and LncRNA NEAT1 expression was detected by Real time PCR. The hepatoma cell line HepG2 was cultured and transfected with lnc RNA NEAT1 siRNA or lnc RNA NEAT1 plasmid followed by analysis of LncRNA NEAT1 expression, cell proliferation by MTT assay, as well as Caspase 3 activity. In addition, cell apoptosis and cell cycle were assessed by flow cytometry and cell invasion was measured by transwell chambers. The expression of EGFR, Bax and Bcl-2 was detected by Western blot.

RESULTS

LncRNA NEAT1 expression was significantly increased in HCC tissues compared with adjacent tissues (p < 0.05). Compared with the siRNA group, transfection of lncRNA NEAT1 siRNA into HepG2 cells significantly inhibited cell proliferation, increased Caspase 3 activity and apoptosis, reduced cell invasion, as well as arrested cell cycle (p < 0.05). Meanwhile, lncRNA NEAT1 siRNA also significantly decreased Bcl-2 and EGFR expression and increased Bax expression (p < 0.05). Transfection of lncRNA NEAT1 plasmid in hepatoma cells HepG2 reversed the above changes, compared with vector group, the differences were statistically significant (p < 0.05).

CONCLUSIONS

LncRNA NEAT1 expression is increased in liver cancer tissues. Down-regulation of LncRNA NEAT1 can inhibit EGFR expression and promote hepatoma cell apoptosis, inhibit cell cycle, thus inhibiting tumor proliferation and invasion.

Effects of phenol on extracellular polymeric substances and microbial communities from aerobic granular sludge treating low strength and salinity wastewater

The effects of phenol on aerobic granular sludge including extracellular polymeric substances (EPS) and microbial community were investigated for low strength and salinity wastewater treatment. Elevated phenol over 20 mg/L stimulated biological phosphorus removal mainly via co-metabolism with nearly complete phenol degradation, whereas resulted in significant accumulation of nitrate around 4 mg/L. Aerobic granules kept structural stability via enhancing production of extracellular polymeric substances (EPS), especially folds of polysaccharides (PS) and varying functional groups identified through EEM, FTIR and XPS spectral characterizations at increasing phenol loads. Illumina MiSeq sequencing results indicated that elevated phenol decreased the bacterial diversity and richness, and caused remarkable variations in structural and compositions of microbial population. Multiple halophilic bacteria including Stappia, Luteococcus, and Formosa laid the biological basis for stability of aerobic granules and efficient biological nutrients and phenol removal. Redundancy analysis (RDA) suggested the key role of phenol in shaping the relative abundances and predominant genera. This study proved that aerobic granular sludge was feasible for low-saline and phenol-laden low-strength wastewater treatment.

Interaction and removal of oxytetracycline with aerobic granular sludge

Aerobic granular sludge as a promising technology showed great resistance to adverse conditions. However, the interaction between oxytetracycline (OTC) and granular sludge was not studied sufficiently. This study therefore investigated OTC-tolerance ability of incomplete and complete granulation sludge from aspects of simultaneous nutrients removal, sludge characteristics, microbial activity, community changes, and vice versa OTC removal performance. Incomplete granulation sludge showed better denitrification performance and resistance. Whereas, denitrification and phosphorus removal of complete granulation sludge suffered a permanent collapse under 5 mg/L OTC. OTC could be removed by rapid adsorption and slow biodegradation via granular sludge. The EPS, especially TB-PS, played a significant role during the operational period subjected to OTC. The major genera of Lysobacter and Candidatus_Competibacter laid the biological basis for stability and functionality of granules, which acted as the putative contributors for resisting and removing OTC. This study showed that incomplete-granulated sludge qualified more promising application prospect.

Tanshinone ⅡA may alleviate rifampin-induced cholestasis by regulating the expression and function of NTCP

The Na⁺-taurocholate cotransporting polypeptide (NTCP) acts as the major hepatic basolateral uptake system, and plays a key role in balancing bile flow. The anti-tuberculosis drugs rifampin (RFP) can affect bile flow causing liver injury, while tanshinone IIA (TAN IIA) has the effect of protecting liver. This study aimed to investigate the effects of RFP and TAN IIA on the NTCP expression and activity, and explore the potential connections. Herein, we established sandwich-cultured primary rat hepatocytes, and quantified mRNA and protein levels of NRF2 and NTCP after treatment with RFP (10, 25, or 50 μM) or co-treatment with TAN IIA (5, 10, or 20 μM) for 12, 24, 48 h (n = 3). NTCP activity was assessed by measuring the initial uptake rates of known substrates taurocholate (TCA) (n = 3) after treatment with different concentrations of RFP, TAN ⅡA for 12, 24 and 48 h. We found that RFP had inhibition effects on NRF2, NTCP mRNA and protein expression, and co-administration of TAN IIA could reverse RFP inhibition. TCA cellular accumulation was significantly decreased by RFP (39.1%), and TAN IIA could significantly induce TCA uptake of NTCP (2.9-fold at 48 h). The TCA uptake activity was correlated with the NTCP mRNA expression, confirming the role of RFP or TAN IIA on NTCP expression and activity is synchronous, and we can predict NTCP activity by detecting its mRNA expression. In conclusion, our work will enrich the significance of NTCP in the liver protection, and provide theoretical basis for TAN IIA to prevent RFP induced cholestatic liver injury.

The STING-IRF3 pathway is involved in lipotoxic injury of pancreatic β cells in type 2 diabetes

Lipotoxic injury of pancreatic β cells is an important pathological feature in type 2 diabetes mellitus (T2DM). Stimulator of interferon genes (STING) can recognize its own DNA leaked into the cytoplasm from damaged mitochondria or nuclei of the host cell, thus activating its downstream factor interferon regulatory factor 3 (IRF3), causing inflammation and apoptosis. The STING-IRF3 signaling pathway is closely related to glycolipid metabolism, but its relationship with the lipotoxicity of pancreatic β cells has rarely been reported. Here, we investigated the role of the STING-IRF3 signaling pathway in lipotoxicity-induced inflammation, apoptosis, and dysfunction of pancreatic β cells. We examined the activation of STING and IRF3 in islets of db/db mice and identified the role of the STING-IRF3 signaling pathway in palmitic acid (PA)-induced lipotoxic injury of INS-1, a rat insulinoma cell line. STING and phosphorylated IRF3 including downstream interferon-β were upregulated in islets of db/db mice and PA-induced INS-1 cells. Gene silencing of STING or IRF3 ameliorated PA-induced INS-1 cell inflammation and apoptosis, and reversed impaired insulin synthesis. Additionally, PA induced downregulation of the phosphoinositide 3-kinase-AKT signaling pathway, and impaired high glucose-stimulated insulin secretion was reversed after knockdown of STING or IRF3. Our results suggest that activation of the STING-IRF3 pathway triggers inflammation and apoptosis of pancreatic β cells, leading to β-cell damage and dysfunction. Hence, inhibition of this signaling pathway may represent a novel approach for β-cell protection in T2DM.

MicroRNA miR-927 targets the juvenile hormone primary response gene Krüppel homolog1 to control Drosophila developmental growth

Krüppel homolog1 (Kr-h1) is a juvenile hormone (JH) response transcriptional factor that transduces JH signalling to repress insect metamorphosis in both hemimetabolous and holometabolous insects. While few studies about microRNAs (miRNAs) downregulating Kr-h1 expression to mediate insect metamorphosis have been demonstrated in hemimetabolous insects, the miRNAs that target the Kr-h1 of holometabolous insects have not been reported. Here, we identified two miR-927 binding sites within the 3'UTR region of Kr-h1 in Drosophila melanogaster, and miR-927 was found to downregulate the expression of Kr-h1. The expression profiles of miR-927 and Kr-h1 displayed relatively opposite pattern during most of the larval development stages. Overexpression of miR-927 in the fat body significantly decreased the expression of Kr-h1 and resulted in reduced oviposition, increased mortality, delayed pupation, and reduced pupal size. Notably, the co-overexpression of Kr-h1 rescued the developmental and growth defects associated with miR-927 overexpression, indicating that Kr-h1 is a biologically relevant target of miR-927. Moreover, the expression of miR-927 was found to be repressed by JH and its receptor Met/gce, forming a positive regulatory loop of JH signalling. Overall, our studies support a conserved role for the JH/miRNA/Kr-h1 regulatory axis in growth control during insect development.

Modified staging system for gastric neuroendocrine carcinoma based on American Joint Committee on Cancer and European Neuroendocrine Tumor Society systems

BACKGROUND

The prognostic values of the AJCC staging system for gastric cancer (GC-AJCC), the AJCC staging system for gastric neuroendocrine tumours (NET-AJCC) and the European Neuroendocrine Tumor Society (ENETS) system for gastric neuroendocrine carcinoma and mixed adenoneuroendocrine carcinoma (MA)NEC remain controversial.

METHODS

Data on patients with (MA)NEC from 21 centres in China were analysed. Different staging systems were evaluated by performing Kaplan-Meier survival analysis and calculating the concordance index (C-index) and Akaike information criterion (AIC). Based on three existing systems, a modified staging system (mTNM) was developed.

RESULTS

A total of 871 patients were included. In the GC-AJCC system, an overlap was noticed for pT2 and pT3 categories. Patients with stage IIIC disease had a similar prognosis to those with stage IV disease. The pT categories of the NET-AJCC system had a lower C-index and higher AIC than those of the other systems. In the ENETS system, there was a low proportion (0·2 per cent) of patients with stage IIIA and a high proportion (67·6 per cent) of stage IIIB disease. The mTNM system adopted the NET-AJCC pT and GC-AJCC pN and pM definitions, and was developed based on the ENETS stage definitions. The proportion of patients in each stage was better distributed and the mTNM system showed improved prognostic performance in predicting overall and disease-free survival.

CONCLUSION

The mTNM system offers more accurate prognostic value for gastric (MA)NEC than the AJCC or ENETS staging systems.

Reduced serum miR-98 predicts unfavorable clinical outcome of colorectal cancer

OBJECTIVE

Circulating microRNAs (miRNAs) are considered to be promising biomarkers for the diagnosis and prognosis prediction of cancers. However, the potential clinical significance of the serum miR-98 in colorectal cancer (CRC) remained unclear. This study aimed to examine the serum miR-98 levels in CRC patients and explore its potential value for CRC.

PATIENTS AND METHODS

A total of 115 CRC cases and 50 healthy volunteers were enrolled in this study. Quantitative reverse-transcription PCR (qRT-PCR) was performed to detect serum miR-98 expression in all the participants.

RESULTS

The results revealed that serum miR-98 levels were frequently downregulated in CRC patients compared with controls. In addition, low serum miR-98 levels were closely associated with aggressive clinical features and shorter survival. Receiver operating characteristic (ROC) curve analysis demonstrated that serum miR-98 could well differentiate CRC patients from healthy controls with relatively high accuracy. Multivariate analysis further demonstrated that serum miR-98 was an independent prognostic factor for both overall survival and disease-free survival. Mechanistically, MYC, IL-6, and HIST1H2BH were identified as direct downstream targets of miR-98 in CRC cells.

CONCLUSIONS

Collectively, serum miR-98 might be useful as an indicator for predicting the clinical outcome of CRC patients.

Effects of dissolved oxygen concentrations on a bioaugmented sequencing batch rector treating aniline-laden wastewater: Reactor performance, microbial dynamics and functional genes

This work compared the efficiencies and internal reasons for aniline removal in a bioaugmented sequencing batch reactor at elevated dissolved oxygen (DO) concentrations. Nearly complete aniline removal was achieved while medium DO of 2.65 mg/L was optimal for subsequent nitrogen removal via heterotrophic nitrification-aerobic denitrification. Apart from the highest bacterial diversity richness, favorable DO condition largely enriched putatively aniline degrader, nitrifiers and denitrifiers. Further evidence from qPCR confirmed that moderate DO significantly stimulated the functional genes including aniline degrading gene tad, nitrifying genes amoA, hao, and denitrifying genes nirS and napA, respectively. This study indicates that the significant enrichment of key microorganisms and effective functional genes under optimal DO is the inner mechanism for reliable aniline degradation and subsequent nitrogen removal in the activated sludge reactor.

Long non-coding RNA LINC01287 promotes breast cancer cells proliferation and metastasis by activating Wnt/ß-catenin signaling

OBJECTIVE

Long noncoding RNA (lncRNAs) frequently exhibited abnormal levels in numerous tumors and other diseases in current biological researches. LINC01287, a newly discovered lncRNA, has been found to act as an oncogene in hepatocellular carcinoma. The aim of this research was to explore the expressions and functions of LINC01287 in breast cancer (BC).

PATIENTS AND METHODS

The relative expressions of LINC01287 in BC tissues and cells were determined using RT-PCR. The associations between the LINC01287 expression, the clinicopathological factors, and the overall survival of BC patients were statistically examined. The apoptosis and proliferation abilities of MCF-7 and MDA-MB-468 cells were analyzed by MTT and flow cytometry assay after LINC01287 knockdown. The effects of LINC01287 in migration and invasion were determined using wound-healing and transwell assays. The protein expressions of the Wnt/β-catenin pathway were determined using Western blot.

RESULTS

We showed that the levels of LINC01287 were significantly upregulated in BC tissues and BC cell lines, and the abnormal expressions of LINC01287 were correlated with TNM stage and lymph node metastasis. A distinct difference was observed and indicated that BC patients with higher LINC01287 expressions had significantly shorter overall survival than patients with lower LINC01287 expressions. The multivariate analysis demonstrated that LINC01287 expression was independently correlated with the overall survival. Si-LINC01287 transfection significantly inhibited the proliferation and metastasis of BC cells, and further promoted apoptosis. Besides, the knockdown of LINC01287 suppressed Wnt/β-catenin activation and affected the expressions of β-catenin, cyclin D1, and c-myc.

CONCLUSIONS

Our findings indicated that the new lncRNA LINC01287 was correlated with poor clinical outcome and may function as a novel prognostic biomarker and therapeutic target in the development of antineoplastic therapies for BC.

Correlation study on β2-adrenergic receptor gene polymorphisms and asthma susceptibility: evidence based on 57 case-control studies

OBJECTIVE

Previous studies have indicated that β2-adrenergic receptor (ADRB2) genetic polymorphism is related to the risk of asthma, but the results still have some controversy and uncertainty. To this end, the meta-analysis was performed, including all studies that can be used to assess the correlation between ADRB2 polymorphism and asthma susceptibility.

MATERIALS AND METHODS

The related papers on ADRB2 polymorphisms and asthma were systematically reviewed in databases of PubMed, EMBASE, Cochrane Library, and WanFang, Odds ratios (ORs) and corresponding 95% confidence intervals (95% CIs) were measured. The sensitivity analysis and publication bias were evaluated to investigate the correlation.

RESULTS

This meta-analysis included 57 papers in total involving 11,157 cases and 12,281 controls. Results illustrated that the C79G variant genotypes owned a reduced effect on asthma susceptibility (G vs. C: OR=0.94, p=0.037). In the age stratification analysis, C79G polymorphism owned a reduced effect on asthma risk for children (GG vs. CC: OR=0.69, p=0.002; GG vs. CC+CG: OR=0.65, p<0.001). Furthermore, in the ethnic stratification analysis, the C79G variant genotypes also owned a reduced effect on asthma in Asians (GG vs. CC: OR=0.80, p=0.027; GG vs. CC+CG: OR=0.81, p=0.02). Besides, for A46G polymorphism, the ethnic stratification analysis demonstrated that the A46G variant owned an increased effect on asthma susceptibility among Caucasians (G vs. A: OR=1.15, p=0.043). For C491T polymorphism, a considerable reduced effect was found between C491T and asthma susceptibility for children (CT vs. CC: OR=0.70, p=0.03). In the ethnic stratification analysis, the effect was also considerable in the Caucasian subjects.

CONCLUSIONS

The present meta-analysis demonstrated that C79G and C491T polymorphism may be a defensive factor for asthma, while A46G polymorphism may be a risk factor for asthma among the Caucasian population.