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In this work, a Cd-based metal-organic framework (MOF) {Cd(H2L)2} n (Cd-MOF) (L = 5-(3-carboxypyridin-4-yl)isophthalic acid) has been synthesized solvothermally and characterized. The nitrogen-containing π-electron-rich moieties render Cd-MOF an ideal platform for iodine uptake. Its static adsorption and adsorption kinetics were also investigated. The Cd-MOF efficiently captures iodine and removal efficiency was achieved at 68.6% after 40 h. Furthermore, the Cd-MOF was chosen as the interfacial modification material between the perovskite layer and hole transport layer in the perovskite solar cells (PSCs), Cd-MOF can passivate surface defects and promote hole extraction. Consequently, the Cd-MOF-modified PSCs yield enhanced power conversion efficiencies (PCEs) of 23.71%, outperforming the reference PSCs (21.68%).

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Hypoxia-inducible factors (HIFs) play pivotal roles in numerous diseases and high-altitude adaptation, and HIF stabilizers have emerged as valuable therapeutic tools. In our prior investigation, we identified a highland-adaptation 24-amino-acid insertion within the Epas1 protein. This insertion enhances the protein stability of Epas1, and mice engineered with this insertion display enhanced resilience to hypoxic conditions. In the current study, we delved into the biochemical mechanisms underlying the protein-stabilizing effects of this insertion. Our findings unveiled that the last 11 amino acids within this insertion adopt a helical conformation and interact with the α-domain of the von Hippel-Lindau tumor suppressor protein (pVHL), thereby disrupting the Eloc-pVHL interaction and impeding the ubiquitination of Epas1. Utilizing a synthesized peptide, E14-24, we demonstrated its favorable membrane permeability and ability to stabilize endogenous HIF-α proteins, inducing the expression of hypoxia-responsive element (HRE) genes. Furthermore, the administration of E14-24 to mice subjected to hypoxic conditions mitigated body weight loss, suggesting its potential to enhance hypoxia adaptation.

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The optimization of flame retardancy and thermal conductivity in epoxy resin (EP), utilized in critical applications such as mechanical components and electronics packaging, is a significant challenge. This study introduces a novel, ultrasound-assisted self-assembly technique to create a dual-functional filler consisting of carbon nanotubes and ammonium polyphosphate (CNTs@APP). This method, leveraging dynamic ligand interactions and strategic solvent selection, allows for precise control over the assembly and distribution of CNTs on APP surfaces, distinguishing it from conventional blending approaches. The integration of 7.5 wt.% CNTs@APP10 into EP nanocomposites results in substantial improvements in flame retardancy, as evidenced by a limiting oxygen index (LOI) value of 31.8% and achievement of the UL-94 V-0 rating. Additionally, critical fire hazard indicators, including total heat release (THR), total smoke release (TSR), and the peak intensity of CO yield (PCOY), are significantly reduced by 45.9% to 77.5%. This method also leads to a remarkable 3.6-fold increase in char yield, demonstrating its game-changing potential over traditional blending techniques. Moreover, despite minimal CNTs addition, thermal conductivity is notably enhanced, showing a 53% increase. This study introduces a novel approach in the development of multifunctional EP nanocomposites, offering potential for wide range of applications.

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Crystallinity and flame retardancy are two key properties for poly(lactic acid)(PLA) in applications. In this paper, a quaternary phosphonium salt poly(ionic liquid) (PIL) and a phosphamide (POFA) were prepared. The PIL, POFA and their blend were used to regulate the flame retardancy and crystallization behaviors of PLA using the limiting oxygen index, UL-94 vertical burning, and thermogravimetric analysis, and differential scanning calorimetry etc. The results showed that a synergistic effect exists between PIL and POFA on flame retardancy. When 6 wt% PIL/POFA (2/1) was added into PLA, its LOI value is 28.0 vol%, and achieves the UL-94 V-0 rating while the PLA composites containing 6 wt% PIL or POFA just achieve the UL-94 V2. The PIL/POFA improves the flame retardancy of PLA by melting-away mode. In addition, the crystallization rate of PLA containing PIL/POFA is faster than that of PLA/PIL and PLA/POFA. The degradation of PLA induced by PIL/POFA produces some small molecular oligomers, which enhances the molecular chain mobility and rearrangement, thus contributes to better flame retardancy and faster crystallization.

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Integrating metal-organic framework (MOF)-covalent organic framework (COF) allows versatile engineering of hybrid materials with properties superior to pristine components, especially COFs suffered from aggregation-caused quenching (ACQ), unlocking more possibilities to improve the luminescence of COFs. In this work, we prepared various MOF@COF composites with different COF layer thicknesses, in which stable UiO-66-NH2 served as the inner substrate and 1,3,5-benzenetricarboxaldehyde (BT), and 3,3'-dihydroxybenzidine (DH) were used to construct a COF layer. In addition to the conventional preparation method, we increased the ratio of BT and DH to be 1:2.5, and impressively, the morphologies of acquired UC (1:2.5) materials were quite different from the previous reticular structure and gradually extended from the spherical structure to the prickly structure with the increase of COF monomers. Remarkably, all of the UC materials possessed better luminescence properties than individual COF due to the limited COF layers. Meanwhile, UC-1 materials with an optimal COF layer displayed the strongest emission. In comparison with a single COF, the quantum yields of UC-1 and UC-1 (1:2.5) were increased nearly 7 times and 5 times, respectively. Moreover, the fluorescence of UC-1 materials was progressively enhanced via selective F- sensing. This work is expected to shed light on the potential hybridization of MOF-COF with structural adjustment, morphological design, and luminescence enhancement.

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Luminescent metal-organic frameworks (MOFs) have garnered considerable attention in various fields. Herein, we proposed a hierarchical confinement strategy based on MOF-on-MOF to tune luminescence emission ranging from blue to red including white light in a flexible way. The easily available ZIF-8 MOF was used as a host for the confinement of two kinds of size-matching dyes (perylene and rhodamine B) to obtain a layered ZIF-8@dye@ZIF-8@dye via in situ encapsulation and seed-mediated synthesis. ZIF-8@dye@ZIF-8@dye materials with different fluorescence emission in dispersed and solid states were both obtained by tuning the initial encapsulation concentration of dye and changing the structure of the inner and outer ZIF-8@dye layers. To our delight, ZIF-8@0.125perylene@ZIF-8@25RhB with white light emission in the dispersed state was obtained; meanwhile, ZIF-8@0.125perylene + 25RhB and mechanically mixed ZIF-8@0.125perylene + ZIF-8@25RhB could not realize white light emission under the same conditions, indicating that the proposed hierarchical confinement strategy facilitated white light regulation. Similarly, the emission of ZIF-8@dye@ZIF-8@dye in the solid state has also been investigated; ZIF-8@perylene@ZIF-8@3RhB with white light emission was obtained, while white light emission could not be achieved in ZIF-8@perylene + 3RhB and ZIF-8@perylene + ZIF-8@3RhB, which further indicated the importance of the hierarchical confinement strategy based on MOF-on-MOF. The proposed hierarchical confinement strategy may also inspire the development of other functional optical MOF materials.

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Background: Neuroinflammation is related with the inflammatory stress of brain tissue induced by the activation of microglial in the central nervous system (CNS), which is still an intractable disease for modern clinical system. Chlorogenic acid has multiple biological activities such as antivirus and anti-inflammation, while few researches have revealed its therapeutic functions in neuroinflammation. Methods: BV2 cells were treated with lipopolysaccharide (LPS) to establish neuroinflammation cell models, and the effects and mechanism of chlorogenic acid in improving the inflammatory progression were investigated. In brief, the toxicity of chlorogenic acid on BV2 cells was detected with MTT assay. The levels of the inflammatory factors including TNF-α, IL-6, IL-1ß, and IFN-α were measured with ELISA, and the abundances of TLR4, MyD88, TRIF, and NF-κB were observed by qRT-PCR and western blot. Results: Chlorogenic acid did not exhibit obvious toxic and side effects on BV2 cells. The levels of TNF-α, IL-6, IL-1ß, and IFN-α were observably upregulated in BV2 cells after treating with LPS. Chlorogenic acid significantly reduced the levels of TNF-α, IL-6, IL-1ß, and IFN-α. Moreover, the abundances of TLR4, MyD88, TRIF, and NF-κB were increased in LPS-induced BV2 cells, while chlorogenic acid could obviously reduce their expressions. Conclusion: This study suggests that chlorogenic acid can improve the inflammatory stress of LPS-induced BV2 cell via interacting with the TLR4-mediated downstream pathway, which is a potential drug for neuroinflammation treatment.

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Hepatic stellate cells (HSCs) activation is a key step that promotes hepatic fibrosis. Emerging evidence suggests that aerobic glycolysis is one of its important metabolic characteristics. Our previous study has reported that CD147, a glycosylated transmembrane protein, contributes significantly to the activation of HSCs. However, whether and how it is involved in the aerobic glycolysis of HSCs activation is unknown. The objective of the present study was to validate the effect of CD147 in HSCs activation and the underlying molecular mechanism. Our results showed that the silencing of CD147 decreased the expression of α-smooth muscle-actin (α-SMA) and collagen I at both mRNA and protein levels. Furthermore, CD147 silencing decreased the glucose uptake, lactate production in HSCs, and repressed the lactate dehydrogenase (LDH) activity, the expression of hexokinase 2 (HK2), glucose transporter 1 (Glut1). The effect of galloflavin, a well-defined glycolysis inhibitor, was similar to CD147 siRNA. Mechanistically, CD147 silencing suppressed glycolysis-associated HSCs activation through inhibiting the hedgehog signaling. Moreover, the hedgehog signaling agonist SAG could rescue the above effect of CD147 silencing. In conclusion, CD147 silencing blockade of aerobic glycolysis via suppression of hedgehog signaling inhibited HSCs activation, suggesting CD147 as a novel therapeutic target for hepatic fibrosis. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10616-021-00460-9.

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Bone defect is a common problem and inducing osteoblasts differentiation is the key process for the regenerative repair. Recently, the mesoporous silica (MS) coated nanohydroxyapatite (nHA) particles (nHA-MS) has shown enhanced intrinsic potency for bone regeneration, whereas whether the osteogenesis potency can be further enhanced after drug delivery has not been investigated. In this study, the nHA-MS was fabricated by a novel biphase stratification growth way. The cytotoxicity in MC3T3-E1 was validated by MTT assay, apoptosis analysis and cell cycle examination. The cell uptake was observed by confocal laser scanning microscope and transmission electron microscope respectively. After adsorption with dexamethasone (DEX), the osteogenic differentiation was determined bothin vitroandin vivo. The synthesized nHA-MS showed a core-shell structure that the nanorod-like nHA was coated by a porous MS shell (∼5 nm pores diameter, ∼50 nm thickness). A dose-dependent cytotoxicity was observed and below 10 µg ml-1was a safe concentration. The nHA-MS also showed efficient cell uptake efficiency and more efficient in DEX loading and release. After DEX adsorption, the nanoparticles exhibited enhanced osteogenic induction in MC3T3-E1 and rat calvarial bone defect regeneration. In conclusion, the nHA-MS is a favorable platform for drug delivery to obtain more enhanced osteogenesis capabilities.

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PURPOSE: Perineural invasion (PNI) is reported to correlate with local recurrence and poor prognosis of salivary adenoid cystic carcinoma (SACC). However, the pathogenesis of PNI remains unclear. The aims of this study were to investigate the correlation between sympathetic innervation and SACC PNI and to elucidate how the sympathetic neurotransmitter norepinephrine (NE) regulates the PNI process. MATERIALS AND METHODS: Sympathetic innervation and ß2-adrenergic receptor (ß2-AR) expression in SACC tissues were evaluated by immunohistochemistry. The NE concentrations in SACC tissues and dorsal root ganglia (DRG) coculture models were measured by ELISA. ß2-AR expression in SACC cells was detected by performing quantitative real-time polymerase chain reaction (qRT-PCR) and immunofluorescence assay. SACC cells were treated with NE, the nonselective α-AR blocker phentolamine, the ß2-AR antagonist ICI118,551, or were transfected with ß2-AR small interfering RNA (siRNA). Proliferation was evaluated in methyl thiazolyl tetrazolium assay, and migration was evaluated in Transwell assay and wound-healing assay. PNI was tested through both Transwell assay and a DRG coculture model. The expressions of epithelial-mesenchymal transition (EMT) markers and matrix metalloproteinases (MMPs) were measured by performing qRT-PCR and Western blot assay. RESULTS: Sympathetic innervation and ß2-AR were highly distributed in SACC tissues and correlated positively with PNI (P=0.035 and P=0.003, respectively). The sympathetic neurotransmitter NE was overexpressed in SACC tissues and DRG coculture models. Exogenously added NE promoted proliferation, migration, and PNI of SACC cells via ß2-AR activation. NE/ß2-AR signaling may promote proliferation, migration, and PNI by inducing EMT and upregulating MMPs. However, ß2-AR inhibition with either an antagonist or siRNA abrogated NE-induced PNI. CONCLUSION: Collectively, our findings reveal the supportive role of sympathetic innervation in the pathogenesis of SACC PNI and suggest ß2-AR as a potential therapeutic target for treating PNI in SACC.

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Tongue squamous cell carcinoma (TSCC) is the most common type of oral cancer and is an aggressive head and neck malignancy. Increasing studies have demonstrated that long noncoding RNAs (lncRNAs) play important roles in diverse biological cell processes, such as cell development, fate decisions, cell differentiation, cell migration, and invasion. In our study, we showed that long noncoding RNA colorectal neoplasia differentially expressed (CRNDE) expression was upregulated in TSCC cell lines and tissues. Overexpression of CRNDE increased the TSCC cell proliferation, cell cycle, and cell invasion. Moreover, ectopic expression of CRNDE inhibited the miR-384 expression in the SCC1 cell and increased the Kirsten Ras (KRAS), cell division cycle 42, and insulin receptor substrate 1 expression, which were the direct target genes of miR-384. We demonstrated that the miR-384 expression was downregulated in the TSCC samples compared with the paired adjacent nontumor samples. The expression of CRNDE was negatively correlated with the expression of miR-384 in the TSCC samples. Overexpression of miR-384 suppressed TSCC cell proliferation, cell cycle, and invasion. Furthermore, we demonstrated that CRNDE promoted TSCC cell proliferation and invasion through inhibiting miR-384 expression. These results suggested that CRNDE acts as an oncogene in the development of TSCC, which partially occurs through inhibiting miR-384 expression.

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Breast cancer is one of the most common malignant tumors among females. Recent studies demonstrated that microRNAs (miRNAs) played an important role in the regulation of tumor progression. In our present study, we firstly detected miR-340-5p expression in breast cancer cell lines and found lower expression of miR-340-5p in breast cancer cell lines (MCF-7, MDA-MB-231, BT-549, ZR-75-1) through qRT-PCR. Overexpressed miR-340-5p inhibited cell proliferation and drug resistance to docetaxel with enhanced cell apoptosis of breast cancer cells. Through bioinformatic prediction, we found that LGR5 was a potential target of miR-340-5p. LGR5 was highly expressed in breast cancer cells. Relative expression of LGR5 was negatively regulated by miR-340-5p. Knockdown of LGR5 also inhibited cell proliferation and drug resistance to docetaxel with enhanced cell apoptosis of breast cancer cells. Moreover, knockdown of LGR5 decreased the expression of ß-catenin, c-myc, Survivin. The activation of Wnt/ß-catenin pathway contracted the effects of LGR5 siRNA, indicating that LGR5 siRNA inhibited cell proliferation and drug resistance with induced apoptosis via suppressing Wnt/ß-catenin signaling pathway in breast cancer. Taken together, our study demonstrated that overexpressed miR-340-5p inhibited cell proliferation and drug resistance with increased apoptosis of breast cancer cells through down-regulating LGR5 expression via Wnt/ß-catenin pathway. The miR-340-5p/LGR5 axis may provide a new perspective for treatment for breast cancer.

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Oral squamous cell carcinoma (OSCC) cells are usually resistant to doxorubicin, resulting in limited application of doxorubicin in OSCC treatment. MicroRNA (miR)­221 has been reported to be involved in the development of OSCC; however, it remains unclear if and how miR­221 is implicated in modulating the sensitivity of OSCC cells to doxorubicin. In the present study, reverse transcription­quantitative polymerase chain reaction (RT­qPCR) was used to assess miR­221 expression in OSCC cells in response to doxorubicin treatment. In addition, the SCC4 and SCC9 OSCC cell lines were transfected with anti­miR­221 oligonucleotides and cell viability and apoptosis following doxorubicin treatment were evaluated using an MTT assay and Annexin V­fluorescein isothiocyanate/Hoechst double staining, respectively. The mRNA and protein expression levels of tissue inhibitor of metalloproteinase­3 (TIMP3) in anti­miR­221­transfected cells were assessed using RT­qPCR and western blot analysis, respectively. Furthermore, a luciferase reporter assay was performed to investigate whether TIMP3 may be a direct target gene of miR­221. To explore the roles of TIMP3 in miR­221­mediated cell responses, TIMP3 expression was silenced following transfection with TIMP3­targeting small interfering (si)RNA in cells overexpressing miR­221, and cell viability and apoptosis in response to doxorubicin treatment were measured. The results of the present study demonstrated that miR­221 expression was upregulated in SCC4 and SCC9 cells following treatment with doxorubicin. However, inhibiting the doxorubicin­induced upregulation of miR­221 through transfection with anti­miR­221 oligonucleotides led to an increase in the sensitivity of OSCC cells to doxorubicin. In addition, the results indicated that TIMP3 was a direct target of miR­221 in OSCC cells, as determined by a 3'­untranslated region luciferase reporter assay. Co­transfection of cells with anti­miR­221 oligonucleotides and TIMP3­specific small interfering RNA resulted in reduced sensitivity to doxorubicin compared with the cells transfected with the miR­221 inhibitor alone. In conclusion, these results indicated that OSCC cells are resistant to doxorubicin through upregulation of miR­221, which in turn downregulates TIMP3. Therefore, silencing miR­221 or upregulating TIMP3 may be considered promising therapeutic approaches to enhance the sensitivity of OSCC to doxorubicin.

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The aim of this study was to construct nomograms to predict long-term overall survival (OS) and tongue cancer-specific survival (TCSS) of tongue squamous cell carcinoma (TSCC) patients based on clinical and tumor characteristics. Clinical, tumor, and treatment characteristics of 12,674 patients diagnosed with TSCC between 2004 and 2013 were collected from the Surveillance, Epidemiology, and End Results database. These patients were then divided into surgery and nonsurgery cohorts, and nomograms were developed for each of these groups. The step-down method and cumulative incidence function were used for model selection to determine the significant prognostic factors associated with OS and TCSS. These prognostic variables were incorporated into nomograms. An external cohort was used to validate the surgery nomograms. Seven variables were used to create the surgery nomograms for OS and TCSS, which had c-indexes of 0.709 and 0.728, respectively; for the external validation cohort, the c-indexes were 0.691 and 0.711, respectively. Nine variables were used to create the nonsurgery nomograms for OS and TCSS, which had c-indexes of 0.750 and 0.754, respectively. The calibration curves of the 5- and 8-year surgery and nonsurgery nomograms showed excellent agreement between the probabilities and observed values. By incorporating clinicopathological and host characteristics in patients, we are the first to establish nomograms that accurately predict prognosis for individual patients with TSCC. These nomograms ought to provide more personalized and reliable prognostic information, and improve clinical decision-making for TSCC patients.

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KAI1/CD82 is a metastatic suppressor gene in human prostate cancer and several other types of cancer in humans. The present study aimed to examine the role of the overexpression of KAI1 in the progression of oral cancer. Human KAI1/CD82 cDNA was transfected into OSCC­15 and 293T cell lines, and its effects on OSCC­15 cell proliferation, invasion and apoptosis were assessed by performing a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay, Matrigel invasion and Annexin V­FITC staining, respectively. In addition, a xenograft model was used to assess the effect of KAI1/CD82 on the in vivo growth of tumors. The overexpression of KAI1/CD82 inhibited the proliferation and invasion of OSCC-15 cells. It also enhanced the apoptotic rate of the OSCC­15 cells. Furthermore, the overexpression of KAI1/CD82 inhibited tumor growth in the xenograft model. The results demonstrated that the overexpression of KAI1/CD82 significantly inhibited the proliferation and invasion of human oral cancer cells, and inhibited tumor growth in the xenograft model. Therefore, KAI1/CD82 may be considered as a potential therapeutic target in oral cancer.

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OBJECTIVE: We performed a systematic review to assess the prognostic value of perineural invasion (PNI) for patients with head and neck adenoid cystic carcinoma. STUDY DESIGN: A literature search of MEDLINE and EMBASE was used to identify relevant literature up to December 2015. The primary outcomes of interest were overall survival, disease-free survival, and locoregional control. Study information and hazard ratios (HRs) were extracted, and HRs were pooled using the Mantel-Haenszel fixed-effects model and the DerSimonian and Laird random-effects model according to heterogeneity. RESULTS: Twenty-two studies and 1332 patients were included in this study. The PNI ratio was 43.2%. PNI was at increasing risk for overall survival (HR = 2.98; 95% confidence interval [CI] 2.00-4.46), disease-free survival (HR = 1.88; 95% CI, 1.42-2.49), and locoregional control (HR = 2.15; 95% CI, 1.48-3.13) with statistical significance. CONCLUSIONS: PNI is an independent factor for poor prognosis in patients with head and neck adenoid cystic carcinoma. Moreover, PNI poses a significantly higher threat to male patients and younger patients.

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p12 cyclin-dependent kinase 2 (CDK2)-associating protein 1 (p12CDK2-AP1) has been demonstrated to negatively regulate the activity of CDK2. However, the underlying molecular mechanism remains largely unknown. We aimed to determine the potential binding proteins of p12CDK2-AP1 and to elucidate the role of p12CDK2-AP1 in the regulation of the proliferation, invasion, apoptosis, and in vivo growth of human oral squamous cell carcinoma cells. The protein-protein interaction was predicted using computational decision templates. The predicted p12CDK2­AP1 interacting proteins were overexpressed in human oral squamous cell carcinoma OSCC-15 cells, and the protein binding was examined using co-precipitation (Co-IP). Cell proliferation and invasion were determined via MTT assay and Transwell system, respectively. Cell apoptosis was evaluated using Annexin V-FITC/PI double staining followed by flow cytometric analysis. The in vivo growth of OSCC-15 cells was examined in nude mouse tumor xenografts. We found that overexpression of either p12CDK2-AP1 or CD82 significantly suppressed the proliferation and invasion but promoted the apoptosis of OSCC-15 cells (P<0.05). Importantly, combined overexpression of p12CDK2-AP1 and CD82 showed synergistic antitumor activity compared with the overexpression of a single protein alone (P<0.05). Additionally, the simultaneous overexpression of p12CDK2-AP1 and CD82 significantly suppressed the in vivo tumor growth of OSCC-15 cells in nude mice compared with the negative control (P<0.05). Our findings indicate that p12CDK2-AP1 interacts with CD82 to play a functional role in suppressing the in vitro and in vivo growth of OSCC-15 cells.

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MicroRNAs (miRNAs) represent a class of endogenous non-coding small RNAs that play important roles in multiple biological processes by degrading targeted mRNAs or repressing mRNA translation. Thousands of miRNAs have been identified in many plant species, whereas only a limited number of miRNAs have been predicted in M. acuminata (A genome) and M. balbisiana (B genome). Here, previously known plant miRNAs were BLASTed against the Expressed Sequence Tag (EST) and Genomic Survey Sequence (GSS), a database of banana genes. A total of 32 potential miRNAs belonging to 13 miRNAs families were detected using a range of filtering criteria. 244 miRNA:target pairs were subsequently predicted, most of which encode transcription factors or enzymes that participate in the regulation of development, growth, metabolism, and other physiological processes. In order to validate the predicted miRNAs and the mutual relationship between miRNAs and their target genes, qRT-PCR was applied to detect the tissue-specific expression levels of 12 putative miRNAs and 6 target genes in roots, leaves, flowers, and fruits. This study provides some important information about banana pre-miRNAs, mature miRNAs, and miRNA target genes and these findings can be applied to future research of miRNA functions.

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Cytokinins (CKs) regulate plant development and growth via a two-component signaling pathway. By forward genetic screening, we isolated an Arabidopsis mutant named grow fast on cytokinins 1 (gfc1), whose seedlings grew larger aerial parts on MS medium with CK. gfc1 is allelic to a previously reported cutin mutant defective in cuticular ridges (dcr). GFC1/DCR encodes a soluble BAHD acyltransferase (a name based on the first four enzymes characterized in this family: Benzylalcohol O-acetyltransferase, Anthocyanin O-hydroxycinnamoyltransferase, anthranilate N-hydroxycinnamoyl/benzoyltransferase and Deacetylvindoline 4-O-acetyltransferase) with diacylglycerol acyltransferase (DGAT) activity in vitro and is necessary for normal cuticle formation on epidermis in vivo. Here we show that gfc1 was a CK-insensitive mutant, as revealed by its low regeneration frequency in vitro and resistance to CK in adventitious root formation and dark-grown hypocotyl inhibition assays. In addition, gfc1 had de-etiolated phenotypes in darkness and was therefore defective in skotomorphogenesis. The background expression levels of most type-A Arabidopsis Response Regulator (ARR) genes were higher in the gfc1 mutant. The gfc1-associated phenotypes were also observed in the cutin-deficient glycerol-3-phosphate acyltransferase 4/8 (gpat4/8) double mutant [defective in glycerol-3-phosphate (G3P) acyltransferase enzymes GPAT4 and GPAT8, which redundantly catalyze the acylation of G3P by hydroxyl fatty acid (OH-FA)], but not in the cutin-deficient mutant cytochrome p450, family 86, subfamily A, polypeptide 2/aberrant induction of type three 1 (cyp86A2/att1), which affects the biosynthesis of some OH-FAs. Our results indicate that some acyltransferases associated with cutin formation are involved in CK responses and skotomorphogenesis in Arabidopsis.

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Salivary adenoid cystic carcinoma (SACC) has a unique tendency for perineural invasion (PNI), which results in tumor recurrence and poor prognosis. Recent studies have shown that the chemokine CCL5 and its receptor CCR5 play important roles in tumor invasion and metastasis. However, the role of the CCL5/CCR5 axis in the PNI of SACC has not been studied to date. In the present study, we evaluated the expression of CCL5 and CCR5 in SACC cases and nerve tissues, and performed a series of in vitro assays with the SACC cell line, SACC-83, to indicate the role of the CCL5/CCR5 axis in the PNI of SACC. We found that CCL5 (35.9%; 23/64) and CCR5 (70.3%; 45/64) were positively expressed in SACC cases, and the expression of CCR5 was significantly associated with the PNI of SACC (P<0.05). We also found that SACC-83 cells expressed the functional receptor, CCR5, for the chemokine CCL5, as demonstrated by calcium mobilization and actin polymerization assays. Furthermore, we found that exogenous CCL5 significantly facilitated the migration, invasion and PNI activity of SACC-83 cells in vitro (P<0.05). Further study showed that the CCR5 inhibitor (maraviroc) effectively blocked the migration, invasion and PNI activity of SACC-83 cells with or without CCL5 stimulation (P<0.05). These results indicate that the CCL5/CCR5 axis plays a critical role in the PNI of SACC, and that antagonists against CCR5 may be an effective anti-PNI agent for SACC therapy.

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