Using the generalized dynamic factor model, this study constructs three predictors of crude oil price volatility: a fundamental (physical) predictor, a financial predictor, and a macroeconomic ...uncertainty predictor. Moreover, an event‐triggered predictor is constructed using data extracted from Google Trends. We construct GARCH‐MIDAS (generalized autoregressive conditional heteroskedasticity–mixed‐data sampling) models combining realized volatility with the predictors to predict oil price volatility at different forecasting horizons. We then identify the predictive power of the realized volatility and the predictors by the model confidence set (MCS) test. The findings show that, among the four indexes, the financial predictor has the most predictive power for crude oil volatility, which provides strong evidence that financialization has been the key determinant of crude oil price behavior since the 2008 global financial crisis. In addition, the fundamental predictor, followed by the financial predictor, effectively forecasts crude oil price volatility in the long‐run forecasting horizons. Our findings indicate that the different predictors can provide distinct predictive information at the different horizons given the specific market situation. These findings have useful implications for market traders in terms of managing crude oil price risk.
Long noncoding RNAs (lncRNAs) play critical roles in the carcinogenesis and progression of cancers. However, the role and mechanism of the pseudogene lncRNA PIN1P1 in gastric carcinoma remain ...unclear. The expression and effects of lncRNA PIN1P1 in gastric cancer were investigated. The transcriptional regulation of CREB1 on PIN1P1 was determined by ChIP and luciferase assays. The mechanistic model of PIN1P1 in gastric cancer was further explored by RNA pull‐down, RIP and western blot analysis. PIN1P1 was overexpressed in gastric cancer tissues, and upregulated PIN1P1 predicted poor prognosis in patients. CREB1 was directly combined with the promoter region of PIN1P1 to promote the transcription of PIN1P1. CREB1‐mediated enhanced proliferation, migration and invasion could be partially reversed by downregulation of PIN1P1. Overexpressed PIN1P1 promoted the proliferation, migration and invasion of gastric cancer cells, whereas decreased PIN1P1 showed the opposite effects. PIN1P1 directly interacted with YBX1 and promoted YBX1 protein expression, leading to upregulation of PIN1, in which E2F1 may be involved. Silencing of YBX1 during PIN1P1 overexpression could partially rescue PIN1 upregulation. PIN1, the parental gene of PIN1P1, was elevated in gastric cancer tissues, and its upregulation was correlated with poor patient outcomes. PIN1 facilitated gastric cancer cell proliferation, migration and invasion. To sum up, CREB1‐activated PIN1P1 could promote gastric cancer progression through YBX1 and upregulating PIN1, suggesting that it is a potential target for gastric cancer.
Gastric cancer (GC) is one of the most common cancers around the world. We demonstrate that SPIN1 is upregulated and associated with poor prognosis in GC. SPIN1 sustains GC cell proliferation via ...activation of MDM2‐p21‐E2F1 signaling pathway by binding to H3K4me3 of the MDM2 promoter. E2F1 could directly bind to the SPIN1 promoter and activate its transcription, forming a positive feedback loop.
Gastric cancer (GC) is one of the most common cancers around the world. Searching for specific gene expression changes during the development of GC could help identify potential therapy targets. We previously showed that the histone code reader SPIN1 may act as an oncogene in breast cancer. At present, the biological function and regulation of SPIN1 in GC remain unclear. Here, we demonstrate that SPIN1 is upregulated in GC tissues, compared with nontumorous gastric tissues. Increased expression of SPIN1 is closely associated with poor prognosis for patients with GC. Increased SPIN1 expression enhances GC cell proliferation, migration, and invasion and promotes cell cycle progression. Mechanically, SPIN1 sustains GC cell proliferation via activation of the MDM2‐p21‐E2F1 signaling pathway by binding to H3K4me3 of the MDM2 promoter region. Interestingly, E2F1 could directly bind to the SPIN1 promoter and activate its transcription, thus forming a positive feedback loop. Our data suggest that SPIN1 plays an important role in the development of GC and could be used as a promising prognostic biomarker and therapeutic target for GC.
Graphene with atomic layer of sp2-hybridized carbon atoms in a hexagonal structure has attracted multidisciplinary attention since its discovery. Due to the inherent advantages of large specific ...surface area and abundant functional groups, its derivative graphene oxide (GO) nanomaterials have achieved large-scale development in effective pollution treatment. In the past few years, novel GO-based nanomaterials through coupling with other nanomaterials have been synthesized with significant process and applied for efficient elimination of different kinds of pollutants. This paper aims to summarize recent research results on the excellent removal ability of GO-based nanomaterials for various heavy metal ions in aqueous solutions. The synthesis, adsorption process characteristics and interaction mechanism of the adsorbent are emphasized and discussed. The effects of various environmental conditions are outlined. At last, a brief summary, perspective and outlook are presented. This review is intended to provide some thrilling information for the design and manufacture of GO-based nanomaterials for the elimination of heavy metal ions from wastewater in environmental pollution management.
Display omitted
•Synthesis and surface modification of GO-based composites are reviewed.•Applications of different GO-based composites for metal ions elimination are reviewed.•Interaction mechanism of metal ions with GO-based composites is discussed.•Sorption capacities of metal ions on GO-based composites and other materials are compared.•Perspective of GO-based composites in pollution management is summarized.
The synthesis of graphene oxide-based materials and their application in the efficient elimination of different metal ions are summarized and compared with other materials. The interaction mechanism is discussed in detail.
Accumulating evidence demonstrated that long noncoding RNAs (lncRNAs) played important regulatory roles in many cancer types. However, the role of lncRNAs in gastric cancer (GC) progression remains ...unclear.
RT-qPCR assay was performed to detect the expression of HNF1A-AS1 in gastric cancer tissues and the non-tumourous gastric mucosa. Overexpression and RNA interference approaches were used to investigate the effects of HNF1A-AS1 on GC cells. Insight into competitive endogenous RNA (ceRNA) mechanisms was gained via bioinformatics analysis, luciferase assays and an RNA-binding protein immunoprecipitation (RIP) assay, RNA-FISH co-localisation analysis combined with microRNA (miRNA)-pulldown assay.
This study displayed that revealed expression of HNF1A-AS1 was associated with positive lymph node metastasis in GC. Moreover, HNF1A-AS1 significantly promoted gastric cancer invasion, metastasis, angiogenesis and lymphangiogenesis in vitro and in vivo. In addition, HNF1A-AS1 was demonstrated to function as a ceRNA for miR-30b-3p. HNF1A-AS1 abolished the function of the miRNA-30b-3p and resulted in the derepression of its target, PIK3CD, which is a core oncogene involved in the progression of GC.
This study demonstrated that HNF1A-AS1 worked as a ceRNA and promoted PI3K/AKT signalling pathway-mediated GC metastasis by sponging miR-30b-3p, offering novel insights of the metastasis mechanism in GC.
Gastric cancer (GC) is one of the most common malignant neoplasms. Invasion and metastasis are the main causes of GC-related deaths. Recently, kinesins were discovered to be involved in tumor ...development. The aim of this study was to elucidate the roles of kinesin superfamily protein 26A (KIF26A) in GC and its underlying molecular mechanism in regulating tumor invasion and metastasis. Using real-time quantitative polymerase chain reaction (qPCR) and immunohistochemistry (IHC), we showed that KIF26A expression was lower in GC tissues without lymph node metastasis (LNM) than in nontumorous gastric mucosa, and even lower in GC tissues with LNM than in GC tissues without LNM. Functional experiments showed that KIF26A inhibited migration and invasion of GC cells. We further identified focal-adhesion kinase (FAK), phosphatidylinositol 3-kinase regulatory subunit alpha (PI3KR1), VAV3, Rac1 and p21-activated kinase 2, and β-PAK (PAK3) as downstream effectors of KIF26A in the focal-adhesion pathway, and we found that KIF26A could regulate FAK mRNA expression through inhibiting c-MYC by MAPK pathway. c-MYC could bind to the promoter of FAK and activate FAK transcription. Moreover, we found that KIF26A-mediated inactivation of the focal-adhesion pathway could reduce the occurrence of the epithelial-to-mesenchymal transition (EMT) by increasing expression of E-cadherin and reducing that of Snail. Luciferase assays and Western blotting revealed that miR-19a and miR-96 negatively regulate KIF26A. Finally, we found that decreased expression of KIF26A has been positively correlated with histological differentiation, Lauren classification, LNM, distal metastasis, and clinical stage, as well as poor survival in patients with GC. These data indicate that KIF26A could inhibit GC migration and invasion by regulating the focal-adhesion pathway and repressing the occurrence of EMT.
Long noncoding RNAs (lncRNAs) are dysregulated in different cancer types, and thus have emerged as important regulators of the initiation and progression of human cancers. However, the biological ...functions and the underlying mechanisms responsible for their functions in gastric cancer (GC) remain poorly understood. Here, by lncRNA microarray, we identified 1414 differentially expressed lncRNAs, among which THAP7-AS1 was significantly upregulated in GC tissues compared with non-tumorous gastric tissues. High expression of THAP7-AS1 was correlated with positive lymph node metastasis and poorer prognosis. SP1, a transcription factor, could bind directly to the THAP7-AS1 promoter region and activate its transcription. Moreover, the m
A modification of THAP7-AS1 by METTL3 enhanced its expression depending on the "reader" protein IGF2BP1-dependent pathway. THAP7-AS1 promoted GC cell progression. Mechanistically, THAP7-AS1 interacted with the 1-50 Amino Acid Region (nuclear localization signal) of CUL4B through its 1-442 nt Sequence, and it promoted interaction between nuclear localization signal (NLS) and importin α1, and improved the CUL4B protein entry into the nucleus, repressing miR-22-3p and miR-320a expression by CUL4B-catalyzed H2AK119ub1 and the EZH2-mediated H3K27me3, subsequently activating PI3K/AKT signaling pathway to promote GC progression. Moreover, LV-sh-THAP7-AS1 treatment could suppress GC growth, invasion and metastasis, indicating that THAP7-AS1 may act as a promising molecular target for GC therapies. Taken together, our results show that THAP7-AS1, transcriptionally activated by SP1 and then modified by METTL3-mediated m6A, exerts oncogenic functions, by promoting interaction between NLS and importin α1 and then improving the CUL4B protein entry into the nucleus to repress the transcription of miR-22-3p and miR-320a.
Long non-coding RNAs (lncRNAs) play important roles in cancer development and progression; however, their contributions to gastric cancer metastasis remain largely unknown. By lncRNA microarray ...screening, our study showed that 453 lncRNAs are dysregulated in gastric cancer tissues with or without lymph node metastasis, of which lnc-LEMGC ranks as one of the most significantly downregulated lncRNAs. Lnc-LEMGC inhibited cell migration and invasion both in vitro and in vivo, by combining with protein DNA-PKcs. Importantly, nucleotides 1300–1800 of lnc-LEMGC prevented DNA-PKcs phosphorylation of serine 2056 and partially abrogated the effects of downstream effectors, ErbB1, SRC and protein tyrosine kinase 2 (FAK), in the epidermal growth factor receptor (EGFR) pathway. The results of this study extend our knowledge of lncRNA's molecular mechanisms, in which lnc-LEMGC functions by directly suppressing the phosphorylation of its combined protein DNA-PKcs and inactivating the DNA-PKcs downstream EGFR signaling.
•WHAT IS CURRENT KNOWLEDGE.●Lymph node metastasis and distant metastasis is the chief cause of cancer-related death.●LncRNAs can apply diverse modes of action to regulate cancer processes.●EGFR pathway is one of most frequently activated signaling pathway in gastric cancer.2.WHAT IS NEW HERE●Differential expression lncRNA profiles in gastric cancer samples with or without metastases.●Lnc-LEMGC is down-regulated in metastatic gastric cancer tissues, compared to tissues without metastases.●A direct experimental evidence for the anti-oncogene role of lnc-LEMGC in vitro and in vivo.●Lnc-LEMGC functions by directly suppressing the phosphorylation of its combined protein DNA-PKcs and inactivating the DNA-PKcs downstream EGFR signaling.
Background
Gastric cancer is the fourth leading cause of cancer-related deaths worldwide. And patient outcomes are poor due to tumor relapse and metastasis. To develop new therapeutic strategies, it ...is of great importance to explore the mechanism underlying the progression of gastric cancer.
Methods
Primary gastric cancer samples with lymph node metastases (LNM) and without LNM were subjected to mRNA microarray assay. The differentially expressed genes were confirmed by RT-qPCR. HRCT1 protein expression was further detected using an immunohistochemistry (IHC) assay. In vitro and in vivo assays were performed to investigate the role of HRCT1 in tumor invasion, metastasis, and proliferation. The expressions of the downstream target genes of HRCT1 were detected by microarray, RT-qPCR and Western blot assays. Dual-luciferase reporter and Western blot assays were carried out to identify miRNAs target to HRCT1.
Results
HRCT1 was upregulated in gastric cancer, and high expression of HRCT1 was associated with poor overall survival (OS) and disease-free survival (DFS). Moreover, HRCT1protein expression was an independent predictor for poor OS and DFS. HRCT1 could promote gastric cancer cells’ migration, invasion, and proliferation in vitro as well as tumor metastasis and growth in vivo. Notably, our data showed that HRCT1 promoted gastric cancer progression by activating the ERBB2-MAPK signaling pathway. At least partially, the expression of HRCT1 could be negatively regulated by miR-124-3p.
Conclusions
The upregulated expression of HRCT1 predicts poor survival for patients with gastric cancer. HRCT1 promotes tumor progression by activating the ERBB2-MAPK pathway. HRCT1, negatively regulated by miR-124-3p, may be a potential therapeutic target for patients with gastric cancer.