Nomograms for Predicting Risk and Survival of Esophageal Cancer Lung Metastases: a SEER Analysis.

Background: The overall survival rate is notably low for esophageal cancer patients with lung metastases (LM), presenting significant challenges in their treatment. Methods: Through the Surveillance, Epidemiology, and End Results (SEER) program, individuals diagnosed with esophageal cancer between 2010 and 2015 were enrolled. Based on whether esophageal cancer metastasized to the lungs, we used propensity score matching (PSM) to balance correlated variables. Propensity score matching was a critical step in our study that helped to minimize the impact of possible confounders on the study results. We balanced variables related to lung metastases using the PSM method to ensure more accurate comparisons between the study and control groups. Specifically, we performed PSM in the following steps. First, we performed a univariate logistic regression analysis to screen for variables associated with lung metastasis. For each patient, we calculated their propensity scores using a logistic regression model, taking into account several factors, including gender, T-stage, N-stage, surgical history, radiotherapy history, chemotherapy history, and bone/brain/liver metastases. We used a 1:1 matching ratio based on the propensity score to ensure more balanced baseline characteristics between the study and control groups after matching. After matching, we validated the balance of baseline characteristics to ensure that the effect of confounders was minimized. We used logistic regression to identify risk variables for LM, while Cox regression was used to find independent prognostic factors. We then created nomograms and assessed their accuracy using the calibration curve, receiver operating curves (ROC), and C index. Results: In the post-PSM cohort, individuals diagnosed with LM experienced a median overall survival (OS) of 5.0 months (95% confidence interval [CI] 4.3-5.7), which was significantly lower than those without LM (P<0.001). LM has been associated to sex, T stage, N stage, surgery, radiation, chemotherapy, and bone/brain/liver metastases. LM survival was affected by radiation, chemotherapy, and bone/liver metastases. The nomograms' predictive power was proved using the ROC curve, C-index, and validation curve. Conclusion: Patients with LM have a worse chance of surviving esophageal cancer. The nomograms can effectively predict the risk and prognosis of lung metastases from esophageal cancer.

FOXO1 reshapes neutrophils to aggravate acute brain damage and promote late depression after traumatic brain injury.

BACKGROUND: Neutrophils are traditionally viewed as first responders but have a short onset of action in response to traumatic brain injury (TBI). However, the heterogeneity, multifunctionality, and time-dependent modulation of brain damage and outcome mediated by neutrophils after TBI remain poorly understood. METHODS: Using the combined single-cell transcriptomics, metabolomics, and proteomics analysis from TBI patients and the TBI mouse model, we investigate a novel neutrophil phenotype and its associated effects on TBI outcome by neurological deficit scoring and behavioral tests. We also characterized the underlying mechanisms both in vitro and in vivo through molecular simulations, signaling detections, gene expression regulation assessments [including dual-luciferase reporter and chromatin immunoprecipitation (ChIP) assays], primary cultures or co-cultures of neutrophils and oligodendrocytes, intracellular iron, and lipid hydroperoxide concentration measurements, as well as forkhead box protein O1 (FOXO1) conditional knockout mice. RESULTS: We identified that high expression of the FOXO1 protein was induced in neutrophils after TBI both in TBI patients and the TBI mouse model. Infiltration of these FOXO1high neutrophils in the brain was detected not only in the acute phase but also in the chronic phase post-TBI, aggravating acute brain inflammatory damage and promoting late TBI-induced depression. In the acute stage, FOXO1 upregulated cytoplasmic Versican (VCAN) to interact with the apoptosis regulator B-cell lymphoma-2 (BCL-2)-associated X protein (BAX), suppressing the mitochondrial translocation of BAX, which mediated the antiapoptotic effect companied with enhancing interleukin-6 (IL-6) production of FOXO1high neutrophils. In the chronic stage, the "FOXO1-transferrin receptor (TFRC)" mechanism contributes to FOXO1high neutrophil ferroptosis, disturbing the iron homeostasis of oligodendrocytes and inducing a reduction in myelin basic protein, which contributes to the progression of late depression after TBI. CONCLUSIONS: FOXO1high neutrophils represent a novel neutrophil phenotype that emerges in response to acute and chronic TBI, which provides insight into the heterogeneity, reprogramming activity, and versatility of neutrophils in TBI.

Unlabelled LRET biosensor based on double-stranded DNA for the detection of anthraquinone anticancer drugs.

Based on upconversion nanoparticles (UCNPs) as energy donor and herring sperm DNA (hsDNA) as molecular recognition element, an unlabelled upconversion luminescence (UCL) affinity biosensor was constructed for the detection of anthraquinone (AQ) anticancer drugs in biological fluids. AQ anticancer drugs can insert into the double helix structure of hsDNA on the surface of UCNPs, thereby shortening the distance from UCNPs. Therefore, the luminescence resonance energy transfer (LRET) phenomenon is effectively triggered between UCNPs and AQ anticancer drugs. Hence, AQ anticancer drugs can be quantitatively detected according to the UCL quenching rate. The biosensor showed good sensitivity and stability for the detection of daunorubicin (DNR) and doxorubicin (ADM). For the detection of DNR, the linear range is 1-100 µg·mL-1 with a limit of detection (LOD) of 0.60 µg·mL-1, and for ADM, the linear range is 0.5-100 µg·mL-1 with a LOD of 0.38 µg·mL-1. The proposed biosensor provides a convenient method for monitoring AQ anticancer drugs in clinical biological fluids in the future.

PreS1- targeting chimeric antigen receptor T cells diminish HBV infection in liver humanized FRG mice.

Current therapies control but rarely achieve a cure for hepatitis B virus (HBV) infection. Restoration of the HBV-specific immunity by cell-based therapy represents a potential approach for a cure. In this study, we generated HBV specific CAR T cells based on an antibody 2H5-A14 targeting a preS1 region of the HBV large envelope protein. We show that the A14 CAR T cell is capable of killing hepatocytes infected by HBV with high specificity; adoptive transfer of A14 CAR T cells to HBV infected humanized FRG mice resulted in reductions of all serum and intrahepatic virological markers to levels below the detection limit. A14 CAR T cells treatment increased the levels of human IFN-γ, GM-CSF, and IL-8/CXCL-8 in the mice. These results show that A14 CAR T cells may be further developed for curative therapy against HBV infection by eliminating HBV-infected hepatocytes and inducing production of pro-inflammatory and antiviral cytokines.

Intrinsic and extrinsic factors determining natural killer cell fate: Phenotype and function.

Natural killer (NK) cells are derived from hematopoietic stem cells. They belong to the innate lymphoid cell family, which is an important part of innate immunity. This family plays a role in the body mainly through the release of perforin, granzyme, and various cytokines and is involved in cytotoxicity and cytokine-mediated immune regulation. NK cells involved in normal immune regulation and the tumor microenvironment (TME) can exhibit completely different states. Here, we discuss the growth, development, and function of NK cells in regard to intrinsic and extrinsic factors. Intrinsic factors are those that influence NK cells to promote cell maturation and exert their effector functions under the control of internal metabolism and self-related genes. Extrinsic factors include the metabolism of the TME and the influence of related proteins on the "fate" of NK cells. This review targets the potential of NK cell metabolism, cellular molecules, regulatory genes, and other mechanisms involved in immune regulation. We further discuss immune-mediated tumor therapy, which is the trend of current research.

Two host-guest grown ether supramolecules show switchable phase transition, dielectric and second-harmonic generation effect.

The excellent properties of host-guest crown ether inclusions in phase transition, dielectric and second-order nonlinear optical properties have attracted much attention. In this paper, we successfully designed and prepared two novel host-guest crown ether supramolecules [(DFBA)(15-crown-5)]X (X = ClO4-, 1; ReO4-, 2) by reactions of 2,6-difluorobenzylamine (DFBA) with 1,4,10,13-pentaoxacyclopentadecane (15-crown-5) in HClO4, or HReO4 aqueous solution. By the introduction of difluoro-substituted benzylamine as a guest cation, the phase transition temperatures are greatly increased to 377 K for 1 and 391 K for 2. More importantly, the space group of 1 has changed from centrosymmetric (CS) P2/c to the non-centrosymmetric (NCS) Pca21 in 2 when substituting perchlorate (ClO4-) with the larger and heavier perrhenate (ReO4-), which leads to 2 showing a switchable and stable second-harmonic generation (SHG) effect. According to the principle of momentum matching between a cation and anion, the perrhenate group increases the energy barrier of the molecular thermal motion, which not only significantly increases the phase transition temperature of 2 but also causes it to be frozen and crystallized in a NCS space group at room temperature. This research demonstrates that a polar molecule can adjust the suitability of anions and cations inside the crystal by practical chemical means.

Glutamate blunts cell-killing effects of neutrophils in tumor microenvironment.

Neutrophils are the first defenders of the innate system for injury and infection. They have gradually been recognized as important participants in tumor initiation and development due to their heterogeneity and plasticity. In the tumor microenvironment (TME), neutrophils can exert antitumor and protumor functions, depending on the surroundings. Tumor cells systemically alter intracellular amino acid (AA) metabolism and extracellular AA distribution to meet their proliferation need, leading to metabolic reprogramming and TME reshaping. However, the underlying mechanisms that determine how altered AAs affect neutrophils in TME are less-explored. Here, we identified that abundant glutamate releasing from tumor cells blunted neutrophils' cell-killing effects toward tumor cells in vitro and in vivo. Mass spectrometric detection, flow cytometry, and western blot experiments proved that increased levels of pSTAT3/RAB10/ARF4, mediated by glutamate, were accompanied with immunosuppressive phenotypes of neutrophils in TME. We also discovered that riluzole, an FDA-approved glutamate release inhibitor, significantly inhibited tumor growth by restoring neutrophils' cell-killing effects and decreasing glutamate secretion from tumor cells. These findings highlight the importance of tumor-released glutamate on neutrophil transformation in TME, providing new possible cancer treatments targeting altered glutamate metabolism.

Gaining the Freedom of Scalable Gas Diffusion Electrodes for the CO2 Reduction Reaction.

Gas diffusion electrodes (GDEs) in CO2 reduction reaction (CO2RR) alleviate the mass transfer limitation of gaseous reagents, which is beneficial for reducing CO2 into valuable chemicals. GDEs offer higher current densities compared to electrodes immersed in the electrolyte. Disclosing the roles of different structural parameters in tuning the performance of the GDEs is essential to exert the potential of catalysts and to meet potential large-scale industrial applications of the CO2RR. A novel layer structure for the airbrush-type spray fabrication of GDEs was designed and optimised, comprising a carbon-based gas-diffusion layer, a PEEK fabric, a Ni mesh, a carbon-integrated catalyst layer, and a PTFE top layer. It was shown that adjusting the carbon material in the gas diffusion and the catalyst layer impacts the selectivity of the CO2RR due to the modulation of the pore network. This work disclosed a practical and scalable but also an easily transferable pathway for preparing GDEs and offered an idea of how to tune the significant parameters of GDEs for optimising their CO2RR performance.

Potent and Specific Inhibition of NTCP-Mediated HBV/HDV Infection and Substrate Transporting by a Novel, Oral-Available Cyclosporine A Analogue.

Analogues of the natural product cyclosporine A (CsA) were developed and assessed as antivirals against infection of hepatitis B virus (HBV) and its satellite hepatitis D virus (HDV). An analogue termed 27A exhibits potent inhibition of HBV/HDV infection by specifically blocking viral engagement to its cellular receptor NTCP, while it lacks immunosuppressive activity found in natural CsA. Intraperitoneal injection or oral intake of 27A protects HDV-susceptible mouse model from HDV infection. 27A serves as a promising lead for the development of novel anti-HDV/HBV agents.

Liver X receptor inhibits the growth of hepatocellular carcinoma cells via regulating HULC/miR-134-5p/FOXM1 axis.

Hepatocellular carcinoma (HCC) is one of the most common malignancies with a high rate of mortality. Highly upregulated in liver cancer (HULC), the specifically overexpressed long non-coding RNA in human HCC, plays important roles in promoting the growth and metastasis of HCC cells. So downregulating HULC will be benefit to HCC treatment. The nuclear receptor LXR (liver X receptor), consist of α and ß isoforms, exerts significant anti-HCC effects, but the corresponding mechanisms are not well known, especially, it's unclear whether LXR is involved in the regulation of HULC. In this study, we found that LXR inhibited HCC cell growth by downregulating HULC, and LXRα (but not LXRß) caused HULC downregulation. Luciferase reporter assays showed that LXR suppressed transcriptional activity of HULC gene promoter, and chromatin immunoprecipitation assays revealed that LXRα (but not LXRß) bound to HULC promoter region. Furthermore, LXR increased miR-134-5p while decreased FOXM1 by reducing HULC. Additionally, HULC upregulated FOXM1 via sequestrating miR-134-5p, and miR-134-5p downregulated FOXM1 by targeting 3'-UTR of its mRNA. The in vivo experiments showed that LXR repressed the growth of HCC xenografts, and decreased HULC and FOXM1 while increased miR-134-5p in the xenografts. In summary, these findings for the first time demonstrate that LXR inhibits HCC cell growth by modulating HULC/miR-134-5p/FOXM1 axis, suggesting that the pathway LXR/HULC/miR-134-5p/FOXM1 may serve as a novel target for HCC treatment.

Homochiral Nickel Nitrite ABX3 (X = NO2-) Perovskite Ferroelectrics.

Chiral organic-inorganic perovskites (COIPs) have recently attracted increasing interest due to their unique inherent chirality and potential applications in next-generation optoelectronic and spintronic devices. However, COIP ferroelectrics are very sparse. In this work, for the first time, we present the nickel-nitrite ABX3 COIP ferroelectrics, [(R and S)-N-fluoromethyl-3-quinuclidinol]Ni(NO2)3 ([(R and S)-FMQ]Ni(NO2)3), where the X-site is the rarely seen NO2- bridging ligand. [(R and S)-FMQ]Ni(NO2)3 display mirror-relationship in the crystal structure and vibrational circular dichroism signal. It is emphasized that [(R and S)-FMQ]Ni(NO2)3 show splendid ferroelectricity with both an extremely high phase-transition point of 405 K and a spontaneous polarization of 12 µC/cm2. To our knowledge, [(R and S)-FMQ]Ni(NO2)3 are the first examples of nickel-nitrite based COIP ferroelectrics. This finding expands the COIP family and throws light on exploration of high-performance COIP ferroelectrics.

Dichloroacetate enhances the antitumor effect of pirarubicin via regulating the ROS-JNK signaling pathway in liver cancer cells.

Aim: Liver cancer is one of the most common malignancies and has a high recurrence rate. However, current treatment strategies do not achieve satisfactory outcomes in the clinic. To explore a new strategy to enhance the effectiveness of chemotherapy in liver cancer, we investigated whether dichloroacetate (DCA) could enhance the sensitivity of liver cancer cells to pirarubicin (THP). Methods: Liver cancer cells were treated with DCA alone, THP alone, or DCA and THP combined. Cell viability was determined by the CCK-8 assay. Cell apoptosis was analyzed by flow cytometer. Reactive oxygen species (ROS) were detected using a CM-H2DCFDA fluorescence probe. Protein levels were identified by immunoblotting. Results: The results revealed that DCA significantly enhanced the antitumor effect of THP in liver cancer cells. Changes in morphology and adherence ability were observed, as well as decreased cell viability. The results of flow cytometry showed that the combination of THP and DCA significantly increased apoptosis of liver cancer cells. Moreover, compared with THP alone, combination treatment with DCA significantly increased THP-triggered ROS generation in liver cancer cells. The antioxidant N-acetyl-L-cysteine reversed the synergistic effect of DCA and THP on ROS generation, cell viability and apoptosis. Furthermore, phosphorylation of c-Jun N-terminal kinase (JNK) was significantly increased in the DCA and THP combination group. The effects of DCA and THP on cell viability and apoptosis were inhibited by the JNK inhibitor SP600125. Conclusion: The results obtained in the present study indicated that DCA enhanced the antitumor effect of THP in liver cancer cells via regulating the ROS-JNK signaling pathway.

A reversible RNA on-switch that controls gene expression of AAV-delivered therapeutics in vivo.

Widespread use of gene therapy technologies is limited in part by the lack of small genetic switches with wide dynamic ranges that control transgene expression without the requirement of additional protein components1-5. In this study, we engineered a class of type III hammerhead ribozymes to develop RNA switches that are highly efficient at cis-cleaving mammalian mRNAs and showed that they can be tightly regulated by a steric-blocking antisense oligonucleotide. Our variant ribozymes enabled in vivo regulation of adeno-associated virus (AAV)-delivered transgenes, allowing dose-dependent and up to 223-fold regulation of protein expression over at least 43 weeks. To test the potential of these reversible on-switches in gene therapy for anemia of chronic kidney disease6, we demonstrated regulated expression of physiological levels of erythropoietin with a well-tolerated dose of the inducer oligonucleotide. These small, modular and efficient RNA switches may improve the safety and efficacy of gene therapies and broaden their use.

Increased sulfation of bile acids in mice and human subjects with sodium taurocholate cotransporting polypeptide deficiency.

Sodium taurocholate cotransporting polypeptide (NTCP, encoded by Slc10a1/SLC10A1) deficiency can result in hypercholanemia but no obvious symptoms in both mice and humans. However, the consequence of and response to long-term hypercholanemia caused by NTCP deficiency remain largely unexplored. Here, we analyzed lifelong dynamics of serum total bile acid (TBA) levels in Slc10a1-/- mice, and we also assessed changes of TBA levels in 33 young individuals with SLC10A1 loss-of-function variant p.Ser267Phe. We found that overall serum TBA levels tended to decrease gradually with age in both Slc10a1-/- mice and p.Ser267Phe individuals. Liver mRNA profiling revealed notable transcription alterations in hypercholanemic Slc10a1-/- mice, including inhibition of bile acid (BA) synthesis, enhancement of BA detoxification, and altered BA transport. Members of the sulfotransferase (SULT) family showed the most dramatic increases in livers of hypercholanemic Slc10a1-/- mice, and one of their BA sulfates, taurolithocholic acid 3-sulfate, significantly increased. Importantly, consistent with the mouse studies, comprehensive profiling of 58 BA species in sera of p.Ser267Phe individuals revealed a markedly increased level of BA sulfates. Together, our findings indicate that the enhanced BA sulfation is a major mechanism for BA detoxification and elimination in both mice and humans with Slc10a1/SLC10A1 deficiency.

Acridone Derivate Simultaneously Featuring Multiple Functions and Its Applications.

Compared with plenty of single-functional molecules, multifunctional molecules are scarce and have high demand in further research. In this work, a multifunctional molecule called 10-methyl-2-amino-acridone (MAA) is presented. Interestingly, MAA simultaneously features electrochemistry, two-photon fluorescence, visible-light-induced oxidase mimic, and photoelectrochemistry (PEC) activity, and the related properties are studied in detailed. Multiple functions integrated into one molecule allow MAA to become a versatile signal probe. Therefore, the MAA acted as an electrochemical indicator to detect exosomal total protein with high sensitivity at first. In addition, MAA is used for one- or two-photon fluorescence imaging in vitro and in vivo, including cells, three-dimensional (3D) tumor spheroids, zebrafish, and exosomes. The results suggest that MAA not only possesses favorable photostability, but it is also suitable for imaging in deep tissue. Furthermore, the visible-light-induced oxidase mimic and photoelectrochemical activities of MAA are selectively inhibited by Cu2+, and the relevant mechanism is carefully analyzed. On the basis of this phenomenon, we develop a dual-modal detection strategy for detection of Cu2+ in river water. Compared with a single signal readout model, this strategy is able to avoid false positive and negative detection through two series of data mutually validating each other. Therefore, our study shows that the "multiple-in-one" MAA provides a blueprint for the investigation and application of a multifunctional organic molecule.

Visfatin is regulated by interleukin­6 and affected by the PPAR­Î³ pathway in BeWo cells.

Visfatin, an adipocytokine and cytosolic enzyme with nicotinamide phosphoribosyltransferase (Nampt) activity, is involved in the pathogenesis of numerous metabolic disorders. In addition, the nuclear receptor peroxisome proliferator­activated receptor­Î³ (PPAR­Î³) serves important roles in anti­inflammatory reactions and regulates glucose and lipid metabolism. The aim of the present study was to investigate the effect of interleukin­6 (IL­6) on the expression and secretion of visfatin in BeWo cells, and to determine whether the PPAR­Î³ pathway is involved in the regulation of visfatin by IL­6. Therefore, BeWo cells were stimulated with serial concentrations of IL­6 or pioglitazone, and the expression levels of visfatin and PPAR­Î³ were determined by reverse transcription­quantitative polymerase chain reaction and western blotting. The results of the present study demonstrated that IL­6 downregulated the mRNA levels of visfatin and PPAR­Î³, which were strongly associated. Activation of PPAR­Î³ by pioglitazone resulted in significantly increased expression of visfatin, which abrogated the inhibitory effect of IL­6 on visfatin in BeWo cells. Furthermore, treatment using pioglitazone alone increased the expression and secretion of the visfatin protein, compared with the control or IL­6 alone group. In summary, the findings of the present study suggested that IL­6 inhibited the expression of visfatin and PPAR­Î³ at the transcriptional level; in addition, activation of PPAR­Î³ upregulated visfatin at the mRNA and protein expression levels. Therefore, the PPAR­Î³ signaling pathway may be involved in the regulation of visfatin by IL­6 in BeWo cells. These results may provide novel insight into the roles of visfatin in trophoblastic cells. Furthermore, thiazolidinedione pioglitazone, by upregulating visfatin expression, may promote the energy metabolism of trophoblastic cells, maintain the function of the placenta and improve the outcome of pregnancy.

Discovery of a novel cathepsin inhibitor with dual autophagy-inducing and metastasis-inhibiting effects on breast cancer cells.

Drug resistance and cancer cells metastasis have been the leading causes of chemotherapy failure and cancer-associated death in breast cancer patients. In present, various active molecules either exhibiting novel mechanism of action such as inducing autophagy or inhibiting metastasis have been developed to address these problems. However, the compounds exhibiting such dual functions have rarely been described. Previous work in our group showed that TSA, as a synthetic analog of asperphenamate, induced autophagic cell death in breast cancer cells instead of apoptosis. Furthermore, the target enzyme of TSA was predicted to be cathepin L (Cat L) by natural product consensus pharmacophore strategy. Accumulated evidences have shown that cathepsins are closely associated with migration and invasion of breast cancer cells. It seemed likely that TSA-like molecules may possess the dual functions of inducing autophagy and inhibiting metastasis. Therefore, sixty optically active derivatives were firstly designed and synthesized by replacing the A-ring moiety of TSA with other substituted-phenyl sulfonyl groups. Further cathepsin inhibitory activity assay showed that (S, S) and (S, R) isomers displayed no activity against four kinds of cathepsins (L, S, K, B), while all derivatives tested were inactive toward K and B subtypes. Compound 6a with meta-bromo substituent displayed the greatest inhibitory activity, and its inhibitory capability against Cat L and S was 3.9 and 11.5-fold more potent than that of TSA, respectively. Molecular docking also exhibited that 6a formed more hydrogen bonds or π-π contacts with Cat L or S than TSA. In order to determine whether 6a could play dual roles, its anti-cancer mechanism was further investigated. On the one hand, MDC staining experiment and western blotting analysis validated that 6a can induce autophagy in MDA-MB-231 cells. On the other hand, its metastatic inhibitory ability was also confirmed by wound healing and transwell chamber experiment.

Discovery of novel cathepsin inhibitors with potent anti-metastatic effects in breast cancer cells.

It is still challenging to determine the potential targets of natural products, which is essential for further drug research and development. Due to its novel mechanism of action of inducing autophagy effects in breast cancer cells, asperphenamate has received our considerable attention. However, its unknown target inevitably impedes further study. In our previous work, the target enzyme of asperphenamate was predicted as cathepsin by the natural product consensus pharmacophore strategy. Then, asperphenamate and its three derivatives were chosen to study in detail by molecular docking calculations with AutoDock 4 suite. The docking results showed the three derivatives interacted more tightly with either cathepsin L or cathepsin S than with asperphenamate. The ortho-benzyloxyl phenylacetyl derivative 1 andp-toluenesulfonyl derivative 3 showed similar interactions with cathepsin L and adopted a better geometric shape within the binding pocket than did the N-CBZ-piperidyl analog 2. On the other hand, compound 2 formed more hydrogen bonds than 1 and 3 to make it tightly bind within cathepsin S. The cathepsin inhibitory activity assay verified the molecular simulation results. Compound 2 was remarkably less active than 1 and 3 against cathepsin L. However, compound 2 showed the strongest potency against cathepsin S with IC50 of 13.12 ±â€¯0.29 µM. Considering that cathepsin S plays a vital role in the process of metastasis in breast cancer cells, the inhibitory effect of 2 on migration and invasion was further studied in human breast cancer MDA-MB-231 cells by wound healing and transwell chamber assays. The results illustrated that 2 exhibited an apparent inhibitory ability to the metastasis of MDA-MB-231 cells. Next, 2 will be chosen as a lead compound to develop novel double functional chemotherapeutic agents with both novel mechanisms of action against apoptosis-resistant cancer cells, such as inducing autophagy and inhibiting cancer metastasis.

Silencing Retinoid X Receptor Alpha Expression Enhances Early-Stage Hepatitis B Virus Infection In Cell Cultures.

Multiple steps of the life cycle of hepatitis B virus (HBV) are known to be coupled to hepatic metabolism. However, the details of involvement of the hepatic metabolic milieu in HBV infection remain incompletely understood. Hepatic lipid metabolism is controlled by a complicated transcription factor network centered on retinoid X receptor alpha (RXRα). Here, we report that RXRα negatively regulates HBV infection at an early stage in cell cultures. The RXR-specific agonist bexarotene inhibits HBV in HepG2 cells expressing the sodium taurocholate cotransporting polypeptide (NTCP) (HepG2-NTCP), HepaRG cells, and primary Tupaia hepatocytes (PTHs); reducing RXRα expression significantly enhanced HBV infection in the cells. Transcriptome sequencing (RNA-seq) analysis of HepG2-NTCP cells with a disrupted RXRα gene revealed that reduced gene expression in arachidonic acid (AA)/eicosanoid biosynthesis pathways, including the AA synthases phospholipase A2 group IIA (PLA2G2A), is associated with increased HBV infection. Moreover, exogenous treatment of AA inhibits HBV infection in HepG2-NTCP cells. These data demonstrate that RXRα is an important cellular factor in modulating HBV infection and implicate the participation of AA/eicosanoid biosynthesis pathways in the regulation of HBV infection.IMPORTANCE Understanding how HBV infection is connected with hepatic lipid metabolism may provide new insights into virus infection and its pathogenesis. By a series of genetic studies in combination with transcriptome analysis and pharmacological assays, we here investigated the role of cellular retinoid X receptor alpha (RXRα), a crucial transcription factor for controlling hepatic lipid metabolism, in de novo HBV infection in cell cultures. We found that silencing of RXRα resulted in elevated HBV covalently closed circular DNA (cccDNA) formation and viral antigen production, while activation of RXRα reduced HBV infection efficiency. Our results also showed that silencing phospholipase A2 group IIA (PLA2G2A), a key enzyme of arachidonic acid (AA) synthases, enhanced HBV infection efficiency in HepG2-NTCP cells and that exogenous AA treatment reduced de novo HBV infection in the cells. These findings unveil RXRα as an important cellular factor in modulating HBV infection and may point to a new strategy for host-targeted therapies against HBV.

A ratiometric electrochemical biosensor for the exosomal microRNAs detection based on bipedal DNA walkers propelled by locked nucleic acid modified toehold mediate strand displacement reaction.

Sensitive and selective detection of microRNAs (miRNAs) in cancer cells derived exosomes have attracted rapidly growing interest owing to their potential in diagnostic and prognostic applications. Here, we design a ratiometric electrochemical biosensor based on bipedal DNA walkers for the attomolar detection of exosomal miR-21. In the presence of miR-21, DNA walkers are activated to walk continuously along DNA tracks, resulting in conformational changes as well as considerable increases of the signal ratio produced by target-respond and target-independent reporters. With the signal cascade amplification of DNA walkers, the biosensor exhibits ultrahigh sensitivity with the limit of detection (LOD) down to 67 aM. Furthermore, owing to the background-correcting function of target-independent reporters termed as reference reporters, the biosensor is robust and stable enough to be applied in the detection of exosomal miR-21 extracted from breast cancer cell lines and serums. In addition, because locked nucleic acid (LNA) modified toehold mediate strand displacement reaction (TMSDR) has extraordinary discriminative ability, the biosensor displays excellent selectivity even against the single-base-mismatched target. It is worth mentioning that our sensor is regenerative and stable for at least 5 cycles without diminution in sensitivity. In brief, the high sensitivity, selectivity and reproducibility, together with cheap, make the proposed biosensor a promising approach for exosomal miRNAs detection, in conjunction with early point-of-care testing (POCT) of cancer.