The Interplay between KSHV Infection and DNA-Sensing Pathways.

During viral infection, the innate immune system utilizes a variety of specific intracellular sensors to detect virus-derived nucleic acids and activate a series of cellular signaling cascades that produce type I IFNs and proinflammatory cytokines and chemokines. Kaposi's sarcoma-associated herpesvirus (KSHV) is an oncogenic double-stranded DNA virus that has been associated with a variety of human malignancies, including Kaposi's sarcoma, primary effusion lymphoma, and multicentric Castleman disease. Infection with KSHV activates various DNA sensors, including cGAS, STING, IFI16, and DExD/H-box helicases. Activation of these DNA sensors induces the innate immune response to antagonize the virus. To counteract this, KSHV has developed countless strategies to evade or inhibit DNA sensing and facilitate its own infection. This review summarizes the major DNA-triggered sensing signaling pathways and details the current knowledge of DNA-sensing mechanisms involved in KSHV infection, as well as how KSHV evades antiviral signaling pathways to successfully establish latent infection and undergo lytic reactivation.

Inhibition of KMO Ameliorates Myocardial Ischemia Injury via Maintaining Mitochondrial Fusion and Fission Balance.

Looking for early diagnostic markers and therapeutic targets is the key to ensuring prompt treatment of myocardial ischemia (MI). Here, a novel biomarker xanthurenic acid (XA) was identified based on metabolomics and exhibited high sensitivity and specificity in the diagnosis of MI patients. Additionally, the elevation of XA was proved to induce myocardial injury in vivo by promoting myocardial apoptosis and ferroptosis. Combining metabolomics and transcriptional data further revealed that kynurenine 3-monooxygenase (KMO) profoundly increased in MI mice, and was closely associated with the elevation of XA. More importantly, pharmacological or heart-specific inhibition of KMO obviously suppressed the elevation of XA and profoundly ameliorated the OGD-induced cardiomyocytes injury and the ligation-induced MI injury. Mechanistically, KMO inhibition effectively restrained myocardial apoptosis and ferroptosis by modulating mitochondrial fission and fusion. In addition, virtual screening and experimental validation were adopted to identify ginsenoside Rb3 as a novel inhibitor of KMO and exhibited great cardioprotective effects by regulating mitochondrial dynamical balance. Taken together, targeting KMO may provide a new approach for the clinical treatment of MI through maintaining mitochondrial fusion and fission balance, and ginsenoside Rb3 showed great potential to be developed as a novel therapeutic drug targeting KMO.

Metabolomics study of ribavirin in the treatment of orthotopic lung cancer based on UPLC-Q-TOF/MS.

Ribavirin is a common antiviral drug, especially for patients with hepatitis C. Our recent studies demonstrated that ribavirin showed anti-tumor activity in colorectal cancer and hepatocellular carcinoma, but its effects on lung cancer remains unclear. This study aimed to evaluate the anti-tumor activity of ribavirin against lung cancer and elucidate the underlying mechanism. We established orthotopic mouse model of lung cancer (LLC and GLC-82) and employed an ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS)-based metabolomics approach. We found that ribavirin significantly inhibited the proliferation and colony formation of lung cancer cells. Tumor sizes of orthotopic lung cancer in ribavirin-treated groups were also significantly lower than those in control groups. Metabolomics analysis revealed that ribavirin mainly affected 5 metabolic pathways in orthotopic lung tumor models, taurine and hypotaurine metabolism, nicotinate and nicotinamide metabolism, linoleic acid metabolism, arginine biosynthesis and arachidonic acid metabolism. Furthermore, we identified 5 upregulated metabolites including ß-nicotinamide adenine dinucleotide (NAD+), nicotinamide (NAM), taurine, ornithine and citrulline, and 7 downregulated metabolites including 1-methylnicotinamide (MNAM), S-adenosyl-l-homocysteine (SAH), N1-Methyl-2-pyridone-5-carboxamide (2PY), homocysteine (Hcy), linoleic acid, arachidonic acid (AA) and argininosuccinic acid in ribavirin-treated groups. These results provide new insight into the anti-tumor mechanism of ribavirin for lung cancer.

Downregulation of PRMT5 by AMI-1 enhances therapeutic efficacy of compound kushen injection in lung carcinoma in vitro and in vivo.

Protein arginine methyltransferase 5 (PRMT5) is overexpressed in lung carcinoma, which promotes tumor cell proliferation, survival, migration and invasion. Compound Kushen injection (CKI) is a mixture of natural compounds extracted from Kushen and Baituling, which are mainly used to stop in cancer pain and bleeding. Here we found that cell viability and colony formation were inhibited after the incubation of AMI-1. Meanwhile, AMI-1 suppressed cell migration, enhanced apoptosis, induced cell cycle arrest, inhibited PRMT5 expression and histone H3R8 and H4R3 symmetric di-methylation (H3R8me2s and H4R3me2s) accumulation, down-regulated the expression of eukaryotic translation initiation factor 4E (eIF4E) in lung carcinoma cells. Moreover, AMI-1 suppressed tumor growth, decreased H3R8me2s and H4R3me2s accumulation, down-regulated eIF4E expression and increased p53 expression in lung carcinoma xenografts of BALB/c nude mice. Of note, combined and CKI markedly enhanced the anticancer efficacy CKI in lung carcinoma. The above findings demonstrated that AMI-1 has established antineoplastic activity and this role may be associated with affecting the function of eIF4E via inhibiting PRMT5 activity or protein levels in lung carcinoma. This study highlights evidence of novel selective anticancer activity of AMI-1 in combination with CKI in lung carcinoma.

Signature of seven cuproptosis-related lncRNAs as a novel biomarker to predict prognosis and therapeutic response in cervical cancer.

Background: Given the high incidence and high mortality of cervical cancer (CC) among women in developing countries, identifying reliable biomarkers for the prediction of prognosis and therapeutic response is crucial. We constructed a prognostic signature of cuproptosis-related long non-coding RNAs (lncRNAs) as a reference for individualized clinical treatment. Methods: A total of seven cuproptosis-related lncRNAs closely related to the prognosis of patients with CC were identified and used to construct a prognostic signature via least absolute shrinkage and selection operator regression analysis in the training set. The predictive performance of the signature was evaluated by Kaplan-Meier (K-M) analysis, receiver operating characteristic (ROC) analysis, and univariate and multivariate Cox analyses. Functional enrichment analysis and single-sample gene set enrichment analysis were conducted to explore the potential mechanisms of the prognostic signature, and a lncRNA-microRNA-mRNA network was created to investigate the underlying regulatory relationships between lncRNAs and cuproptosis in CC. The associations between the prognostic signature and response to immunotherapy and targeted therapy were also assessed. Finally, the prognostic value of the signature was validated using the CC tissues with clinical information in my own center. Results: A prognostic signature was developed based on seven cuproptosis-related lncRNAs, including five protective factors (AL441992.1, LINC01305, AL354833.2, CNNM3-DT, and SCAT2) and two risk factors (AL354733.3 and AC009902.2). The ROC curves confirmed the superior predictive performance of the signature compared with conventional clinicopathological characteristics in CC. The ion transport-related molecular function and various immune-related biological processes differed significantly between the two risk groups according to functional enrichment analysis. Furthermore, we discovered that individuals in the high-risk group were more likely to respond to immunotherapy and targeted therapies including trametinib and cetuximab than those in the low-risk group. Finally, CC tissues with clinical data from my own center further verify the robustness of the seven-lncRNA risk signature. Conclusion: We generated a cuproptosis-related lncRNA risk signature that could be used to predict prognosis of CC patients. Moreover, the signature could be used to predict response to immunotherapy and chemotherapy and thus could assist clinicians in making personalized treatment plans for CC patients.

Ribavirin inhibits cell proliferation and metastasis and prolongs survival in soft tissue sarcomas by downregulating both protein arginine methyltransferases 1 and 5.

Protein arginine methyltransferases 1 and 5 (PRMT1 and PRMT5) are frequently overexpressed in diverse types of cancers and correlate with poor prognosis, thus making these enzymes potential therapeutic targets. The aim of this study was to assess and elucidate the anti-tumour effect and epigenetic regulatory mechanism of ribavirin in soft tissue sarcomas (STS). We showed that ribavirin inhibited growth and metastasis and prolonged survival in animals bearing STS cells by downregulating the mRNA and protein levels of PRMT1/PRMT5 and attenuating the accumulation of asymmetric and symmetric di-methylation of arginine (ADMA and SDMA). Furthermore, ribavirin lowered the permeability of the peritoneum in KM mice bearing S180 ascites via decreasing the level of vascular endothelial growth factor (VEGF). Ribavirin was a potent inhibitor of cell proliferation and metastasis in STS cells through downregulation of both type I PRMT1 and type II PRMT5. Ribavirin could be used to enhance the efficacy of doxorubicin in STS allograft tumour models.

Stabilities and catapults of truncated carbon nanocones.

Truncated carbon nanocones (CNCs) can be taken as energy suppliers because of their special structures. In this paper, we demonstrate the stability of truncated CNCs under compression and the escape behavior of a fullerene catapulted from a compressed CNC by molecular dynamics simulations and theoretical models. The strain energy of a CNC and cohesive energy between a fullerene and the CNC (due to their van der Waals interactions) dominate the stability and catapulting capability of the cone, which strongly depend on geometrical parameters (apex angle, top radius and height) of each CNC and axial distances between them. In particular, the additional transverse vibration of buckled CNCs after released plays a significant role in their catapulting abilities and efficiencies. Finally, finite element method and experiments are further performed to validate the escape mechanism. This study should be of great importance to providing a theoretical support for designing novel nanodevices in mico/nanoelectromechanical systems.

Ampelopsin-sodium induces apoptosis in human lung adenocarcinoma cell lines by promoting tubulin polymerization in vitro.

Previous studies have demonstrated that ampelopsin (AMP), a type of flavonoid isolated from the stems and leaves of Ampelopsis grossedentata, exhibits anti-cancer activity in various types of cancer. Conversion of AMP into its sodium salt (AMP-Na) conferred enhanced solubility and stability to it. The present study aimed to evaluate the anti-cancer activity of AMP-Na in human lung adenocarcinoma cell lines and to investigate its mechanisms of action. Cell proliferation and viability were assessed by MTT and colony formation assays, and cell migration was determined using a scratch wound healing assay. The cell cycle distribution, apoptosis rate and tubulin immunofluorescence intensity were analyzed using flow cytometry, the cell ultra-microstructure was examined using transmission electron microscopy and the accumulation of tubulin was determined using laser confocal microscopy. The results demonstrated that AMP-Na significantly inhibited the proliferation, clonogenicity and migration of human lung adenocarcinoma cells. Furthermore, AMP-Na induced SPC-A-1 cell apoptosis, and promoted tubulin polymerization. The results suggested that the underlying mechanisms of AMP-Na may involve targeting of microtubules and tubulin polymerization to subsequently disrupt mitosis and induce cell cycle arrest at the S-phase.

Cyclophosphamide versus cyclosporine A therapy in steroid-resistant nephrotic syndrome: a retrospective study with a mean 5-year follow-up.

OBJECTIVE: To compare the clinical efficacy of cyclophosphamide (CTX) and cyclosporine A (CSA) in initial treatment of children with steroid-resistant nephrotic syndrome (SRNS). METHODS: Prospectively maintained databases were reviewed to retrospectively compare two cohorts with SRNS that received peroral administration of 2 to 2.5 mg/kg/d CTX for 3 to 6 months or 1 to 5 mg/kg/d CSA for 2 years until the primary analysis cut-off date during 2007 to 2011. The time to first on-study relapse of SRNS was the primary endpoint. The effective rate was the second endpoint. RESULTS: A total of 127 children with SRNS were included (CTX-treated cohort: n = 62; CSA-treated cohort: n = 65), with a mean 5-year follow-up. CTX-treated children showed a significantly delayed time to first on-study relapse of SRNS compared with CSA-treated children (hazard ratio 0.66, 95% confidence interval 0.32-1.75). The relapse rate (rate/year) in CTX-treated children (1.1 ± 0.1) at the 24-month follow-up was significantly higher than that with CSA (0.4 ± 0.2). This difference persisted until the final follow-up. CONCLUSIONS: CSA is associated with a significantly lower relapse rate and significantly higher effective rate compared with CTX, especially in children with minimal change disease.

Arginine methyltransferase inhibitor 1 exhibits antitumor effects against cervical cancer in vitro and in vivo.

Protein arginine methyltransferase 5 (PRMT5), a type II PRMT, is highly expressed in several types of tumors including cervical cancer. Arginine methyltransferase inhibitor 1 (AMI-1) inhibits solid tumors by targeting PRMT5. However, the effect of AMI-1 on cervical cancer is still unknown. In this study, we provided the first evidence that AMI-1 reduced cervical cancer cell proliferation, colony formation and promoted cell apoptosis in vitro. Suppression of tumorigenicity was also confirmed in vivo. Mechanistic studies revealed that AMI-1 significantly reduced PRMT5 level in cells and mice xenografts model of cervical cancer. These results suggest that AMI-1 inhibits cervical cancer by type II PRMT5.

Large stretchability and failure mechanism of graphene kirigami under tension.

From the macro- to the nanoscale, kirigami structures show novel and tunable properties by tailoring the original two-dimensional sheets. In this study, the large stretchability and failure behavior in graphene nanoribbon kirigami (GNR-k) are obtained using the finite element (FE) method and molecular dynamics (MD) simulations. The carbon-carbon bond in the FE method is equivalent to a nonlinear Timoshenko beam based on the Tersoff-Brenner potential. All the results from the present FE method are in reasonable agreement with those from our MD simulations using the REBO potential. These results from the two methods show that the maximum ultimate strain of GNR-k (around 100%) is around 4 times higher than that of a pristine graphene nanoribbon (GNR), whereas the minimum ultimate stress of GNR-k is around one order of magnitude lower than that of the GNR. In particular, the large stretchability of GNR-k is indirectly proven to be mainly derived from the out-of-plane bending deformation by measuring the nonlinear mechanical properties of paper kirigami. Our results provide physical insights into the origins of the large stretchability of GNR-k and make GNR-k applicable to flexible nanodevices.

The Vibration of a Linear Carbon Chain in Carbon Nanotubes.

An explicit solution for the vibration of a carbon chain inside carbon nanotubes (CNTs) was obtained using continuum modeling of the van der Waals (vdW) interactions between them. The effect of the initial tensile force and the amplitude of the carbon chain as well as the radii of the CNTs on the vibration frequency were analyzed in detail, respectively. Our analytical results show that the vibration frequency of the carbon chain in a (5,5) CNT could be around two orders of magnitude higher than that of an independent carbon chain without initial tensile force. For a given CNT radius, the vibration frequency nonlinearly increases with increasing amplitude and initial tensile force. The obtained analytical cohesive energy and vibration frequency are reasonable by comparison of present molecular dynamics (MD) simulations. These findings will be a great help towards understanding the vibration property of a nanowire in nanotubes, and designing nanoelectromechanical devices.

Asiatic acid ameliorates pulmonary fibrosis induced by bleomycin (BLM) via suppressing pro-fibrotic and inflammatory signaling pathways.

Idiopathic pulmonary fibrosis is known as a life-threatening disease with high mortality and limited therapeutic strategies. In addition, the molecular mechanism by which pulmonary fibrosis developed is not fully understood. Asiatic acid (AA) is a triterpenoid, isolated from Centella asiatica, exhibiting efficient anti-inflammatory and anti-oxidative activities. In our study, we attempted to explore the effect of Asiatic acid on bleomycin (BLM)-induced pulmonary fibrosis in mice. The findings indicated that pre-treatment with Asiatic acid inhibited BLM-induced lung injury and fibrosis progression in mice. Further, Asiatic acid down-regulates inflammatory cells infiltration in bronchoalveolar lavage fluid (BALF) and pro-inflammatory cytokines expression in lung tissue specimens induced by BLM. Also, Asiatic acid apparently suppressed transforming growth factor-beta 1 (TGF-ß1) expression in tissues of lung, accompanied with Collagen I, Collagen III, α-SMA and matrix metalloproteinase (TIMP)-1 decreasing, as well as Smads and ERK1/2 inactivation. Of note, Asiatic acid reduces NOD-like receptor, pyrin domain containing-3 (NLRP3) inflammasome. The findings indicated that Asiatic acid might be an effective candidate for pulmonary fibrosis and inflammation treatment.

The Influence of Crosslink Density on the Failure Behavior in Amorphous Polymers by Molecular Dynamics Simulations.

The crosslink density plays a key role in the mechanical response of the amorphous polymers in previous experiments. However, the mechanism of the influence is still not clear. In this paper, the influence of crosslink density on the failure behavior under tension and shear in amorphous polymers is systematically studied using molecular dynamics simulations. The present results indicate that the ultimate stresses and the broken ratios (the broken bond number to all polymer chain number ratios) increase, as well as the ultimate strains decrease with increasing crosslink density. The strain concentration is clearer with the increase of crosslink density. In other words, a higher crosslink density leads to a higher strain concentration. Hence, the higher strain concentration further reduces the fracture strain. This study implies that the mechanical properties of amorphous polymers can be dominated for different applications by altering the molecular architecture.

Targeting protein arginine methyltransferase 5 inhibits human hepatocellular carcinoma growth via the downregulation of beta-catenin.

BACKGROUND: Protein arginine methyltransferase 5 (PRMT5), a type II PRMT, is highly expressed in some tumors, but its role in hepatocellular carcinoma (HCC) is still unknown. METHODS: PRMT5 level in HCC specimens was determined by immunohistochemical staining and the association with clinicopathologic features was evaluated. PRMT5 was inhibited by AMI-1 (a small molecule inhibitor of PRMTs) or small interference RNA (siRNA). The proliferation of HCC cells was tested by Cell Counting Kit-8, cell migration was evaluated by Transwell assay and cell cycle and apoptosis were analyzed by flow cytometry. The effect of AMI-1 on HCC in vivo was examined by mouse xenograft model. RESULTS: PRMT5 expression was markedly upregulated in HCC tissues, and correlated inversely with overall patient survival. Knockdown of PRMT5 significantly reduced the proliferation of HCC cells, but did not affect the growth of normal liver cells. Furthermore, ß-catenin was identified as a target of PRMT5. Silencing PRMT5 significantly down-regulated the expression of ß-catenin and the downstream effector Cyclin D1 in HCC cells. AMI-1 strongly inhibited HCC growth in vivo, increased the ratio of Bax/Bcl-2, and led to apoptosis and loss of migratory activity in several HCC cells. Meanwhile, AMI-1 decreased the expression levels of symmetric dimethylation of H4 (H4R3me2s), a histone mark of PRMT5. CONCLUSIONS: PRMT5 plays an important role in HCC. PRMT5 may be a promising target for HCC therapy.

Targeting protein arginine methyltransferase 5 inhibits colorectal cancer growth by decreasing arginine methylation of eIF4E and FGFR3.

Protein arginine methyltransferases (PRMTs) plays critical roles in cancer. PRMT5 has been implicated in several types of tumors. However, the role of PRMT5 in cancer development remains to be fully elucidated. Here, we provide evidence that PRMT5 is overexpressed in colorectal cancer (CRC) cells and patient-derived primary tumors, correlated with increased cell growth and decreased overall patient survival. Arginine methyltransferase inhibitor 1 (AMI-1)strongly inhibited tumor growth, increased the ratio of Bax/Bcl-2, and induced apoptosis in mouse CRC xenograt model. AMI-1 also induced apoptosis and decreased the migratory activity in several CRC cells. In CRC xenografts AMI-1 significantly decreased symmetric dimethylation of histone 4 (H4R3me2s), a histone mark of type II PRMT5, but not the expression of H4R3me2a, a histone mark of type I PRMTs. These results suggest that the inhibition of PRMT5 contributes to the antitumor efficacy of AMI-1. Chromatin immunoprecipitation (ChIP) identified FGFR3 and eIF4E as two key genes regulated by PRMT5. PRMT5 knockdown reduced the levels of H4R3me2s and H3R8me2s methylation on FGFR3 and eIF4E promoters, leading to decreased expressions of FGFR3 and eIF4E. Collectively, our findings provide new evidence that PRMT5 plays an important role in CRC pathogenesis through epigenetically regulating arginine methylation of oncogenes such as eIF4E and FGFR3.

Combined use of vitamin D3 and metformin exhibits synergistic chemopreventive effects on colorectal neoplasia in rats and mice.

Vitamin D3 and metformin are widely used in humans for regulating mineral metabolism and as an antidiabetic drug, respectively; and both of them have been shown to have chemopreventive effects against various tumors. This study was designed to investigate the potential synergistic chemopreventive effects of vitamin D3 and metformin against the development of early colon neoplasia in two models. The first model was a 1,2-dimethylhydrazine dihydrochloride (DMH)-induced colon cancer rat model and the second, a DMH-dextran sodium sulfate (DSS)-induced colitis-associated colon neoplasia mouse model. Compared with either vitamin D3 or metformin alone, combined use of vitamin D3 and metformin showed more pronounced effect in reducing the numbers of aberrant crypt foci (ACF) and tumor in the colon. The most prominent inhibitory effects were observed in the vitamin D3 medium dose (100 IU/kg/d) and metformin medium dose (120 mg/kg/d) combination group. Furthermore, our results showed that enhancement of metformin's chemopreventive effects by vitamin D3 was associated with downregulation of S6P expression, via the AMPK (IGFI)/mTOR pathway. In addition, enhancement of vitamin D3's chemopreventive effects by metformin was associated with inhibition of the protein expressions of c-Myc and Cyclin D1, via the vitamin D receptor/ß-catenin pathway. These findings show that the combined use of vitamin D3 and metformin exhibits synergistic effects against the development of early colon neoplasia. They suggest that the combined use of vitamin D3 and metformin may represent a novel strategy for chemoprevention of colorectal cancer.

Ampelopsin sodium exhibits antitumor effects against bladder carcinoma in orthotopic xenograft models.

The aim of this study was to establish xenograft models of tumor in mice bladder and evaluate the antitumor efficacy of ampelopsin sodium (Amp-Na). A total of 2×10 human bladder carcinoma EJ cells and murine sarcoma 180 cells were instilled into the bladder of BALB/c nu/nu mice and Swiss mice after preconditioning to establish the tumor model. Mice bearing orthotopic tumors were treated with Amp-Na by intravenous, intraperitoneal, or intravesical instillation. In addition, the pharmacokinetics property of Amp-Na was investigated in normal BALB/c mice. Our results showed that Amp-Na was excreted mainly through the urine, where it existed at a high concentration. Amp-Na significantly inhibited the proliferation of EJ and sarcoma 180 cells both in vivo and in vitro and this can be at least partially attributed to the cell cycle arrest induced by Amp-Na. This study suggests that the use of Amp-Na is an attractive chemotherapeutic modality for bladder cancer patients.

Anti-tumor efficacy and pre-clinical immunogenicity of IFNα2a-NGR.

Previously studies have shown that tumor-homing peptide NGR enhances the therapeutic efficacy of human interferon α2a (IFNα2a) against tumors. Here we investigated in vivo anti-tumor effect of recombinant human IFNα2a-NGR (rhIFNα2a-NGR) against human lung adenocarcinoma cell line SPC-A-1, A549 and murine Lewis lung carcinoma (LLC) subcutaneously xenografted tumors and further assessed the immunogenicity of rhIFNα2a-NGR in Sprague Dawley (SD) rats and rhesus monkeys. We found that rhIFNα2a-NGR significantly inhibited the growth of SPC-A-1, A549 and LLC cells-xenografted tumors in a dose-dependent manner. Although the antibodies to rhIFNα were detected in the serum of SD rats and rhesus monkeys treated with rhIFNα2a-NGR, these antibodies did not cause obvious pathological consequence. Taken together, these data demonstrate that rhIFNα2a-NGR has obvious anti-tumor efficacy in vivo, perhaps due to the tumor-homing peptide NGR. Thus rhIFNα2a-NGR represents a promising novel drug for effective treatment of cancer.