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Epstein‐Barr virus (EBV) is a tumorigenic virus that can cause various human malignancies such as nasopharyngeal carcinoma (NPC) and gastric cancer (GC). EBV encodes 44 mature micro (mi)RNAs, mostly exhibiting oncogenic properties and promoting cancer progression. However, we have previously found that one EBV‐encoded miRNA, namely EBV‐miR‐BART6‐3p, acts as a tumor suppressor by inhibiting metastasis and invasion. Here, we report that EBV‐miR‐BART6‐3p inhibits the proliferation of EBV‐associated cancers, NPC, and GC, by targeting and downregulating a long non‐coding RNA (lncRNA), LOC553103. Through proteomics analysis, we determined that stathmin (STMN1) is affected by EBV‐miR‐BART6‐3p and LOC553103. Further, via RNA immunoprecipitation and luciferase reporter assay, we confirmed that LOC553103 directly binds and stabilizes the 3′UTR region of STMN1 mRNA. These results indicate that the EBV‐miR‐BART6‐3p/LOC553103/STMN1 axis regulates the expression of cell cycle‐associated proteins, which then inhibit EBV‐associated tumor cell proliferation. These findings provide potential targets or strategies for novel EBV‐related cancer treatments, as well as contributes new insights into the understanding of EBV infection‐related carcinogenesis. [ABSTRACT FROM AUTHOR]

ABSTRACT Owing to their essential influence on human society and natural environment exerted by inducing disasters, such as floods and droughts, further studies on precipitation extremes in China are needed. This study presents the regional frequency and spatial-temporal patterns of precipitation extremes in China based on a high-resolution (0.5° × 0.5°) daily precipitation dataset from 1961 to 2013. With fuzzy c-means, L-moments methods and other scientific statistical tests, a regional frequency analysis ( RFA) is conducted, aiming to further understand the regional and spatial distribution of precipitation extremes across China. The results show that: (1) the whole Mainland China can be divided into 50 homogeneous regions on the basis of the characteristics of mean annual precipitation and location indices. (2) For most of the regions, Generalized Extreme Value ( GEV), Generalized Normal ( GNO) and Pearson type III ( PE3) distributions of precipitation extremes fit well, according to the results of goodness-of-fit ( GOF) test. (3) For RX1DAY, GEV has the best-fit distribution in the east, northeast and southwest of China, whereas GNO distribution mostly fits the northern and parts of southwest and southeast; in addition, regions which fit PE3 and Generalized Logistic ( GLO) distribute dispersedly across the country. (4) For RX5DAY, GEV mainly fits in the middle, southwestern and southern; GNO and PE3 apply best to the northeastern and northern, respectively. (5) Return periods of 20, 50 and 100 years for their best-fit distributions decrease gradually from southeastern China to northwestern China. Compared with the results of GEV distribution fitted to each grid, RFA may provide more accurate estimates of rainfall quantiles. Definitely, the study results will not only benefit further understanding of the unique and complex features of extreme precipitation in the whole Mainland China but also contribute to the nation-scale flood prevention, control and management in the backdrop of the changing climate. [ABSTRACT FROM AUTHOR]

Human SPLUNC1 can suppress nasopharyngeal carcinoma ( NPC) tumor formation; however, the correlation between SPLUNC1expression and NPC patient prognosis has not been reported. In the present study, we used a large-scale sample of 1015 tissue cores to detect SPLUNC1 expression and its association with patient prognosis. SPLUNC1 expression was reduced in NPC samples compared to nontumor nasopharyngeal epithelium tissues. Positive expression of SPLUNC1 in NPC predicted a better prognosis (disease-free survival, P = 0.034; overall survival, P = 0.048). Cox's proportional hazards model revealed that SPLUNC1 could be a significant prognostic factor affecting disease-free survival ( P = 0.027). A c DNA micro-array analyzed by significant analysis of micro-array (SAM) and ingenuity pathway analysis (IPA) revealed that an indirect interaction existed between SPLUNC1 and retinoic acid (RA) in the cancer regulatory network. To further investigate the molecular mechanisms involved, we utilized several bioinformatics tools and identified 12 retinoid X receptors heterodimer binding sites in the promoter region of the SPLUNC1 gene. The transcriptional activity of the SPLUNC1 promoter was up-regulated significantly by all-trans-retinoic acid ( ATRA). SPLUNC1 and retinoic acid receptor expression were induced significantly by ATRA, and removal of ATRA led to a progressive loss of SPLUNC1 and retinoic acid receptor expression. ATRA inhibited proliferation and induced the differentiation of NPC cells. Interestingly, over-expression of SPLUNC1 sensitized NPC cells to ATRA, whereas knockdown of SPLUNC1 in HNE1 cells increased cell viability. Under SPLUNC1 knockdown conditions, differentiation was reversed by ATRA treatment. We concluded that SPLUNC1 could potentially predict prognosis for NPC patients and play an important role in ATRA-induced growth inhibition and differentiation in NPC cells. [ABSTRACT FROM AUTHOR]

Cyclodextrins are among the most popular host compounds in supramolecular chemistry. In this paper we describe a versatile approach to the multivalent functionalization of cyclodextrins by using photochemical thiol-alkene addition reactions ('thiol-ene click chemistry'). Starting from cyclodextrins allylated at the 2-OH, 3-OH and/or 6-OH positions, a range of thiols could be introduced in good to excellent yields. By using alkanethiols substituted with hydroxy, carboxylic acid, ester, protected amine, and tetraethyleneglycol groups, a broad variety of functionalized cyclodextrins was obtained. By using fluorinated alkanethiols, highly fluorinated cyclodextrins (up to 56 wt.-% of fluorine) were obtained in excellent yield. [ABSTRACT FROM AUTHOR]

Rechargeable molecular-cluster batteries (MCBs) based on the manganese cluster complex [Mn12O12(CH3CH2C(CH3)2COO)16(H2O)4] ([Mn12]) that exhibited a capacity of approximately 200 A h kg−1 in the battery voltage range of 4.0 to 2.0 V were developed. In these batteries, the capacity of approximately 100 A h kg−1 in the range of 4.0-3.0 V is caused by a chemical reduction from [Mn12]0 to [Mn12]8−, whereas the other half in the range of 3.0-2.0 V cannot be explained by a redox change of the Mn ions. We performed the cyclic voltammetry (CV) and 7Li solid-state NMR measurements on the Mn12-MCBs to investigate the origin of the capacity below 3.0 V. Pseudo-rectangular-shaped CV curves in the range of 3.0-2.0 V demonstrate the presence of an electrical double-layer (EDL) capacitance in Mn12-MCBs, which corresponds to approximately 100 A h kg−1. 7Li NMR studies suggest that Li ions form an EDL with electrons in carbon black electrodes in the capacitance voltage range. The capacitance effects are not formed by the single-carbon electrodes alone, but appear only in the mixture of Mn12 and the carbon black electrodes. This type of coexistence of capacitance effects and redox reaction in one electrochemical cell is quite unusual and can serve as a new working principle for high-performance energy-storage devices. [ABSTRACT FROM AUTHOR]

In South and Southeast Asia, the habit of chewing betel nuts is prevalent, which leads to oral submucous fibrosis (OSF). OSF is a well‐established precancerous lesion, and a portion of OSF cases eventually progress to oral squamous cell carcinoma (OSCC). However, the specific molecular mechanisms underlying the malignant transformation of OSCC from OSF are poorly understood. In this study, the leading‐edge techniques of Spatial Transcriptomics (ST) and Spatial Metabolomics (SM) are integrated to obtain spatial location information of cancer cells, fibroblasts, and immune cells, as well as the transcriptomic and metabolomic landscapes in OSF‐derived OSCC tissues. This work reveals for the first time that some OSF‐derived OSCC cells undergo partial epithelial–mesenchymal transition (pEMT) within the in situ carcinoma (ISC) region, eventually acquiring fibroblast‐like phenotypes and participating in collagen deposition. Complex interactions among epithelial cells, fibroblasts, and immune cells in the tumor microenvironment are demonstrated. Most importantly, significant metabolic reprogramming in OSF‐derived OSCC, including abnormal polyamine metabolism, potentially playing a pivotal role in promoting tumorigenesis and immune evasion is discovered. The ST and SM data in this study shed new light on deciphering the mechanisms of OSF‐derived OSCC. The work also offers invaluable clues for the prevention and treatment of OSCC. [ABSTRACT FROM AUTHOR]

Single cell RNA sequencing (scRNA‐seq) provides a great convenience for studying tumor occurrence and development for its ability to study gene expression at the individual cell level. However, patient‐derived tumor tissues are composed of multiple types of cells including tumor cells and adjacent non‐malignant cells such as stromal cells and immune cells. The spatial locations of various cells in situ tissues plays a pivotal role in the occurrence and development of tumors, which cannot be elucidated by scRNA‐seq alone. Spatially resolved transcriptomics (SRT) technology emerges timely to explore the unrecognized relationship between the spatial background of a particular cell and its functions, and is increasingly used in cancer research. This review provides a systematic overview of the SRT technologies that are developed, in particular the more widely used cutting‐edge SRT technologies based on next‐generation sequencing (NGS). In addition, the main achievements by SRT technologies in precisely unveiling the underappreciated spatial locations on gene expression and cell function with unprecedented high‐resolution in cancer research are emphasized, with the aim of developing more effective clinical therapeutics oriented to a deeper understanding of the interaction between tumor cells and surrounding non‐malignant cells. [ABSTRACT FROM AUTHOR]

The poor prognosis of serous ovarian cancer (SOC) is due to its high invasive capacity and cisplatin resistance of SOC cells, whereas the molecular mechanisms remain poorly understood. In the present study, the expression and function of non‐muscle myosin heavy chain IIB (MYH10) in SOC are identified by immunohistochemistry, in vitro, and in vivo studies, respectively. The mechanism of MYH10 is demonstrated by co‐immunoprecipitation, GST pull‐down, confocal laser assays, and so on. The results show that the knockdown of MYH10 suppressed SOC cell proliferation, migration, invasion, metastasis, and cisplatin resistance both in vivo and in vitro. Further studies confirm that the MYH10 protein functional domain combines with non‐muscle myosin heavy chain IIA (MYH9) to recruit the deubiquitinating enzyme Ubiquitin‐specific proteases 45 and deubiquitinates snail to inhibit snail degradation, eventually promoting tumorigenesis, progression, and cisplatin resistance in SOC. In clinical samples, MYH10 expression is significantly elevated in SOC samples compared to the paratumor samples. And the expression of MYH10 is positively correlated with MYH9 expression. MYH10+/MYH9+ co‐expression is an independent prognostic factor for predicting SOC patient survival. These findings uncover a key role of the MYH10‐MYH9‐snail axis in SOC carcinogenesis, progression, and cisplatin resistance, and provide potential novel therapeutic targets for SOC intervention. [ABSTRACT FROM AUTHOR]

Epstein‐Barr virus (EBV) infection leads to cancers with an epithelial origin, such as nasopharyngeal cancer and gastric cancer, as well as multiple blood cell‐based malignant tumors, such as lymphoma. Interestingly, EBV is also the first virus found to carry genes encoding miRNAs. EBV encodes 25 types of pre‐miRNAs which are finally processed into 44 mature miRNAs. Most EBV‐encoded miRNAs were found to be involved in the occurrence and development of EBV‐related tumors. However, the function of EBV‐miR‐BART12 remains unclear. The findings of the current study revealed that EBV‐miR‐BART12 binds to the 3'UTR region of Tubulin Polymerization‐Promoting Protein 1 (TPPP1) mRNA and downregulates TPPP1, thereby promoting the invasion and migration of EBV‐related cancers, such as nasopharyngeal cancer and gastric cancer. The mechanism underlying this process was found to be the inhibition of TPPP1 by EBV‐miRNA‐BART12, which, in turn, inhibits the acetylation of α‐tubulin, and promotes the dynamic assembly of microtubules, remodels the cytoskeleton, and enhances the acetylation of β‐catenin. β‐catenin activates epithelial to mesenchymal transition (EMT). These two processes synergistically promote the invasion and metastasis of tumor cells. To the best of our knowledge, this is the first study to reveal the role of EBV‐miRNA‐BART12 in the development of EBV‐related tumors as well as the mechanism underlying this process, and suggests potential targets and strategies for the treatment of EBV‐related tumors. [ABSTRACT FROM AUTHOR]

Nasopharyngeal carcinoma (NPC) is a unique EBV‐associated subtype of head and neck cancer, which has the highest incidence in Southern China and eastern South Asia. The interaction between genetic risk factors and environmental challenge, have been considered to contribute to the development of nasopharyngeal carcinogenesis. Constitutive activation of NF‐κB signaling has been seen in NPC tissues and is associated with unfavorable prognosis. Recently, several whole exome sequencing study consistently revealed that high frequency mutations of NF‐κB pathway negative regulators is common in nasopharyngeal carcinoma, which reinforce the importance of NF‐κB driving oncogenesis. This review focuses on the current state of research in role of NF‐κB in NPC carcinogenesis. We summarized the newly identified loss of function (LOF) mutations on NF‐κB negative regulators leading to it's activation bypass LMP‐1 stimulation. We discussed the critical role of NF‐κB activation in immortalization and transformation of nasopharygeal epithelium. We also depicted how NF‐κB signaling mediated chronic inflammation contribute to persistent EBV infection, immune evasion of EBV infected cells, metabolic reprogramming, and cancer stem cells (CSCs) formation in NPC. Lastly, we discussed the clinical resonance of targeting NF‐κB for NPC precise therapy. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is the most common primary tumor of the liver and the sixth most common lethal cancer worldwide. Recent evidences demonstrated that oxidored nitro domain containing protein 1 (NOR1), a putative tumor suppressor gene, is overexpressed in human HCC tissues. However, the role of NOR1 in HCC development remains unclear. Here, we described that NOR1 protein level is elevated in HCC and is associated with poorer clinical outcome. However, ecotopic overexpression of NOR1 protein in human HCC cell line HepG2 cells had no effect on cells proliferation, migration, and clonality. Immunofluoresence assay indicates NOR1 protein is mainly expressed at CD163 positive M2 tumor associated macrophages (TAMs). To explore the role of NOR1 in the development of HCC, we interrogated the susceptibility of mice lacking the NOR1 gene to DEN‐induced hepatocarcinogenesis. NOR1 deficient mice displayed resistance to DEN‐induced HCC. We also demonstrate that mNOR1 protein is enriched in F4/80 positive Kupffer cells (KCs) infiltrated in DEN induced murine HCC tissues. Loss of NOR1 led to increase of iNOS whereas decrease of Arg1, Ym1 expression in KCs. Overexpression of NOR1 in THP‐1 macrophages led to decrease of iNOS but increase of Arg1. Mechanistic investigations showed that inflammatory cytokines IL‐6, TNF‐α production, and NF‐κB activation were also decreased in NOR1 knockout mice exposed to DEN treatment. Our data suggested that NOR1 is overexpressed in HCC associated TAMs and promotes M2 alternative polarization. Genetic deletion of NOR1 in mice leads to impairment of IL‐6 production and NF‐κB activation, which in turn attenuates DEN‐induced HCC development. [ABSTRACT FROM AUTHOR]