Two risk assessment models for predicting white matter injury in extremely preterm infants.

BACKGROUND: Extremely preterm infants (EPIs) are at high-risk of white matter injury (WMI), leading to long-term neurodevelopmental impairments. We aimed to develop nomograms for WMI. METHODS: The study included patients from 31 provinces, spanning ten years. 6074 patients before 2018 were randomly divided into a training and internal validation group (7:3). The external validation group comprised 1492 patients from 2019. Predictors were identified using the least absolute shrinkage and selection operator (LASSO) and multivariable logistic regression and nomograms were constructed. Models' performance was evaluated using receiver operating characteristic (ROC), decision curve analysis (DCA) and calibration curves. RESULTS: The prenatal nomogram included multiple gestation, premature rupture of membranes (PROM), chorioamnionitis, prenatal glucocorticoids, hypertensive disorder complicating pregnancy (HDCP) and Apgar 1 min, with area under the curve (AUC) of 0.805, 0.816 and 0.799 in the training, internal validation and external validation group, respectively. Days of mechanical ventilation (MV), shock, patent ductus arteriosus (PDA) ligation, intraventricular hemorrhage (IVH) grade III-IV, septicemia, hypothermia and necrotizing enterocolitis (NEC) stage II-III were identified as postpartum predictors. The AUCs were 0.791, 0.813 and 0.823 in the three groups, respectively. DCA and calibration curves showed good clinical utility and consistency. CONCLUSION: The two nomograms provide clinicians with precise and efficient tools for prediction of WMI. IMPACT: This study is a large-sample multicenter study, spanning 10 years. The two nomograms are convenient for identifying high-risk infants early, allowing for reducing poor prognosis.

miR24-2 Promotes Malignant Progression of Human Liver Cancer Stem Cells by Enhancing Tyrosine Kinase Src Epigenetically.

MicroRNA24-2 (miR24-2) is associated with human tumorigenesis; however, its molecular mechanisms are poorly understood. Herein, our findings demonstrate that miR24-2 promotes the proliferation ability in vitro and the tumorigenic ability in vivo in human liver cancer stem cells (hLCSCs). Mechanically, the miR24-2 targets for 3' UTR (2,627-2,648) of protein arginine methyltransferase 7 (PRMT7) inhibit the translational ability of prmt7 gene. Moreover, miR24-2 inhibits the di-/tri-methylation of histone H4 arginine 3 by reducing PRMT7 and then promotes the expression of Nanog via long noncoding RNA HULC. Notably, miR24-2 inhibits histone deacetylase HDAC3 through miR675, which promotes the acetylation of histone H4 at lysine 16. Subsequently, miR24-2 enhances the interaction between LC3 and ATG4 dependent on PI3K and triggers cellular autophagy. Strikingly, miR24-2 inhibits the degradation of pyruvate kinase M1 via autophagosome-P62 in hLCSCs. Furthermore, miR24-2 enhances the activity of Src by promoting the binding of PKM1 to the Src promoter regions in hLCSCs. In particular, our results also indicate that src gene determines the oncogenic functions of miR24-2. These results provided a valuable theoretical basis for the discovery of liver cancer therapeutic targets and diagnosis markers based on miR24-2.

miR24-2 accelerates progression of liver cancer cells by activating Pim1 through tri-methylation of Histone H3 on the ninth lysine.

Several microRNAs are associated with carcinogenesis and tumour progression. Herein, our observations suggest both miR24-2 and Pim1 are up-regulated in human liver cancers, and miR24-2 accelerates growth of liver cancer cells in vitro and in vivo. Mechanistically, miR24-2 increases the expression of N6-adenosine-methyltransferase METTL3 and thereafter promotes the expression of miR6079 via RNA methylation modification. Furthermore, miR6079 targets JMJD2A and then increased the tri-methylation of histone H3 on the ninth lysine (H3K9me3). Therefore, miR24-2 inhibits JMJD2A by increasing miR6079 and then increases H3K9me3. Strikingly, miR24-2 increases the expression of Pim1 dependent on H3K9me3 and METTL3. Notably, our findings suggest that miR24-2 alters several related genes (pHistone H3, SUZ12, SUV39H1, Nanog, MEKK4, pTyr) and accelerates progression of liver cancer cells through Pim1 activation. In particular, Pim1 is required for the oncogenic action of miR24-2 in liver cancer. This study elucidates a novel mechanism for miR24-2 in liver cancer and suggests that miR24-2 may be used as novel therapeutic targets of liver cancer.

Plasmonic Modulation of the Upconversion Luminescence Based on Gold Nanorods for Designing a New Strategy of Sensing MicroRNAs.

Upconversion nanoparticles (UCNPs) have potential applications in biosensing and bioimaging. However, the UCNPs-based sensors constructed by luminescence resonance energy transfer (LRET) always suffer from low quenching efficiency, hindering their application. Therefore, exploring a new strategy to resolve this issue is highly desirable. Herein, a strategy based on the surface plasmon resonance (SPR) effect of gold nanorods (AuNRs) is presented. The luminescence of UCNPs was modulated by adjusting the SiO2 thickness of AuNRs@SiO2 and the structure of UCNPs; an enhancement factor of ≈50 times was obtained. Based on the results of the SPR effect of AuNRs, we designed two kinds of potential upconversion microRNA sensors using microRNA-21 as a model to resolve the problem of the lower quenching efficiency resulting from a dye as a quencher. Studies revealed that the proposed strategy could be successfully used to construct upconversion microRNA sensors for avoiding the limitation of the low quenching efficiency. The sensitivity was ≈10 000 times higher than that of the upconversion sensor using dyes as quenchers. Importantly, the assay of microRNA-21 was successfully achieved using this sensor in human serum samples and human breast cancer cell (MCF-7) lysates. It provides a new method for designing upconversion microRNA sensors and may have potential for use in biosensing and bioimaging.

Semi-rational mutagenesis of an industrial Streptomyces fungicidicus strain for improved enduracidin productivity.

The biosynthesis of the valuable antibiotic enduracidin by Streptomyces fungicidicus TXX3120 is a complex multistep process. To identify the rate-limiting step of the entire biosynthetic process, we carried out a deep RNA sequencing towards the mycelia of TXX3120 at different fermentation stages. Comparative RNA-seq analysis indicated that the expression level of the endC gene during the enduracidin production phase was evidently lower than that of the other relevant genes to enduracidin biosynthesis. This result was further confirmed by quantitative RT-PCR, and the giant non-ribosomal peptide synthase (NRPS) encoded by endC was predicated to be the rate-limiting enzyme in enduracidin biosynthesis. To increase the expression of endC during the enduracidin production phase, a reporter-based selection system was developed by genetically replacing the initial part of the endC gene with a thiostrepton resistance gene (tsr), which will then act as a selectable marker to report the expression level of the rate-limiting gene endC, thereby facilitating the selection of enduracidin-overproducing mutants following random mutagenesis. After one round of mutagenesis, thiostrepton resistance selection, and restoration of the endC gene, three mutant strains with improved endC expression levels were obtained. Their highest enduracidin titers reached 9780.54, 9272.46, and 8849.06 U/mL, respectively representing 2.31-, 2.19-, and 2.09-fold of the initial industrial strain TXX3120. Our research provides a useful strategy for the rational breeding of industrial strains that synthesize complex natural products.

Lighting Up MicroRNA in Living Cells by the Disassembly of Lock-Like DNA-Programmed UCNPs-AuNPs through the Target Cycling Amplification Strategy.

Intracellular microRNAs imaging based on upconversion nanoprobes has great potential in cancer diagnostics and treatments. However, the relatively low detection sensitivity limits their application. Herein, a lock-like DNA (LLD) generated by a hairpin DNA (H1) hybridizing with a bolt DNA (bDNA) sequence is designed, which is used to program upconversion nanoparticles (UCNPs, NaYF4 @NaYF4 :Yb, Er@NaYF4 ) and gold nanoparticles (AuNPs). The upconversion emission is quenched through luminescence resonance energy transfer (LRET). The multiple LLD can be repeatedly opened by one copy of target microRNA under the aid of fuel hairpin DNA strands (H2) to trigger disassembly of AuNPs from the UCNP, resulting in the lighting up of UCNPs with a high detection signal gain. This strategy is verified using microRNA-21 as model. The expression level of microRNA-21 in various cells lines can be sensitively measured in vitro, meanwhile cancer cells and normal cells can be easily and accurately distinguished by intracellular microRNA-21 imaging via the nanoprobes. The detection limit is about 1000 times lower than that of the previously reported upconversion nanoprobes without signal amplification. This is the first time a nonenzymatic signal amplification method has been combined with UCNPs for imaging intracellular microRNAs, which has great potential for cancer diagnosis.

Naf1 Regulates HIV-1 Latency by Suppressing Viral Promoter-Driven Gene Expression in Primary CD4+ T Cells.

HIV-1 latency is characterized by reversible silencing of viral transcription driven by the long terminal repeat (LTR) promoter of HIV-1. Cellular and viral factors regulating LTR activity contribute to HIV-1 latency, and certain repressive cellular factors modulate viral transcription silencing. Nef-associated factor 1 (Naf1) is a host nucleocytoplasmic shuttling protein that regulates multiple cellular signaling pathways and HIV-1 production. We recently reported that nuclear Naf1 promoted nuclear export of unspliced HIV-1 gag mRNA, leading to increased Gag production. Here we demonstrate new functions of Naf1 in regulating HIV-1 persistence. We found that Naf1 contributes to the maintenance of HIV-1 latency by inhibiting LTR-driven HIV-1 gene transcription in a nuclear factor kappa B-dependent manner. Interestingly, Naf1 knockdown significantly enhanced viral reactivation in both latently HIV-1-infected Jurkat T cells and primary central memory CD4+ T cells. Furthermore, Naf1 knockdown in resting CD4+ T cells from HIV-1-infected individuals treated with antiretroviral therapy significantly increased viral reactivation upon T-cell activation, suggesting an important role of Naf1 in modulating HIV-1 latency in vivo Our findings provide new insights for a better understanding of HIV-1 latency and suggest that inhibition of Naf1 activity to activate latently HIV-1-infected cells may be a potential therapeutic strategy. IMPORTANCE: HIV-1 latency is characterized mainly by a reversible silencing of LTR promoter-driven transcription of an integrated provirus. Cellular and viral proteins regulating LTR activity contribute to the modulation of HIV-1 latency. In this study, we found that the host protein Naf1 inhibited HIV-1 LTR-driven transcription of HIV genes and contributed to the maintenance of HIV-1 latency. Our findings provide new insights into the effects of host modulation on HIV-1 latency, which may lead to a potential therapeutic strategy for HIV persistence by targeting the Naf1 protein.

Ficellomycin: an aziridine alkaloid antibiotic with potential therapeutic capacity.

Ficellomycin is an aziridine antibiotic produced by Streptomyces ficellus, which displays high in vitro activity against Gram-positive bacteria including multidrug resistant strains of Staphylococcus aureus. Compared to currently available antibiotics, ficellomycin exhibits a unique mechanism of action-it impairs the semiconservative DNA replication by inducing the formation of deficient 34S DNA fragments, which lack the ability to integrate into larger DNA pieces and eventually the complete bacterial chromosome. Until recently, some important progress has been made in research on ficellomycin synthesis and biosynthesis, opening the perspective to develop a new generation of antibiotics with better clinical performance than the currently used ones. In this review, we will cover the discovery and biological activity of ficellomycin, its biosynthesis, mode of action, and related synthetic analogs. The role of ficellomycin and its analogs as an important source of drug prototypes will be discussed together with future research prospects.

Identification and characterization of the ficellomycin biosynthesis gene cluster from Streptomyces ficellus.

Ficellomycin is a peptide-like antibiotic which exhibits potent in vitro activity against Penicillium oxalicum and Staphylococcus aureus, even against strains resistant to most clinically used antibiotics. The gene cluster responsible for ficellomycin biosynthesis was cloned from Streptomyces ficellus and sequenced. It was found to contain 26 ORFs and is located within 30 kb of contiguous DNA. Targeted disruption of the encoding genes revealed that most were involved in the functional section of ficellomycin biosynthesis, such as peptide assembly, regulation, resistance, and biosynthesis of the precursor of ficellomycin 2-[4-guanidyl-1-azabicyclo[3.1.0]hexan-2-yl] glycine (2-GAHG). Within the 2-GAHG synthesis pathway, a sulfate adenylyltransferase appears to be involved in the synthesis of the pharmaceutically important 1-azabicyclo[3.1.0]hexane ring moiety, which has been reported to cause DNA cross-linking or impairment of semiconservative DNA replication.

Comparison of singleton and twin birth weight reference percentile curves by gestational age and sex in extremely preterm infants: a population-based study.

BACKGROUND: With the increasing survival rate of smaller newborns and twins, previous growth curves may not accurately assess the growth of extremely preterm infants (EPIs). Our study aimed to establish birth weight percentile curves for singletons and twins in EPIs from China and the USA and compare the differences between them. METHODS: In China, EPIs were from 31 provinces, from 2010 to 2021. The collected information was sex, gestational age, birth weight, singletons and twins. We used the generalised additive models for location scale and shape method to construct the birth weight percentile curves by gestational age and sex for EPIs. The National Vital Statistics System database from 2016 to 2021 was also analysed. We compared the differences between the 50th birth weight percentile curves of the two databases. RESULTS: We identified 8768 neonates in China (5536 singletons and 3232 twins) and 121 933 neonates in the USA (97 329 singletons and 24 604 twins). We established the 3rd, 10th, 25th, 50th, 75th, 90th and 97th birth weight reference curves for China and the USA. The results showed that males had higher birth weights than females. In China, for the same gestational age and sex, birth weights in singletons and twins were found to be similar, though singleton males born in China had slightly higher birth weights than male twins. In the USA, birth weights were also similar for females and males, with the same gestational age in singletons and twins. CONCLUSION: We established birth weight reference percentile curves by gestational age and sex for singletons and twins among EPIs in China and the USA.

CircHULC accelerates the growth of human liver cancer stem cells by enhancing chromatin reprogramming and chromosomal instability via autophagy.

BACKGROUND: Although CircHULC was overexpressed in several cancers, the role of CircHULC in malignancies has yet to be elucidated. METHODS: Gene infection, tumorigenesis test in vitro and in vivo and the signaling pathway analysis were performed. RESULTS: our results indicate that CircHULC promotes growth of human liver cancer stem cells and the malignant differentiation of hepatocyte-like cells. Mechanistically, CircHULC enhances the methylation modification of PKM2 via CARM1 and the deacetylase Sirt1. Moreover, CircHULC enhances the binding ability of TP53INP2/DOR with LC3 and LC3 with ATG4, ATG3, ATG5, ATG12. Therefore, CircHULC promotes the formation of autophagosomes. In particular, the binding ability of phosphorylated Beclin1 (Ser14) to Vps15, Vps34, ATG14L were significantly increased after CircHULC was overexpressed. Strikingly, CircHULC affects the expression of chromatin reprogramming factors and oncogenes through autophagy. Thereafter, Oct4, Sox2, KLF4, Nanog, and GADD45 were significantly decreased and C-myc was increased after CircHULC was overexpressed. Thus, CircHULC promotes the expression of H-Ras, SGK, P70S6K, 4E-BP1, Jun, and AKT. Interestingly, both CARM1 and Sirt1 determine the cancerous function of CircHULC dependent on autophagy. CONCLUSIONS: we shed light on the fact that the targeted attenuation of deregulated functioning of CircHULC could be a viable approach for cancer treatment, and CircHULC may acts as the potential biomarker and therapeutic target for liver cancer.

miR-3200 accelerates the growth of liver cancer cells by enhancing Rab7A.

Researches indicate miR-3200 is closely related to tumorigenesis, However, the role of miR-3200 in human hepatocarcinogenesis is still unclear. In this study, we clearly demonstrate that miR-3200 accelerates the growth of liver cancer cells in vivo and in vitro. Obviously, these findings are noteworthy that miR-3200 affects the transcriptional regulation for several genes, including DSP，BABAM2, Rab7A,SQSTM1,PRKAG2,CDK1,ABCE1,BECN1,PTEN,UPRT. And miR-3200 affects the transcriptional ability of several genes, such as, upregulating CADPS, DSP,FBXO32, PPCA,SGK1, PATXN7L1, PLK2,ITGB5,FZD3,HOXC8,HSPA1A,C-Myc,CyclnD1,CyclinE,PCNA and down -regulating SUV39H1, MYO1G, OLFML3, CBX5, PPDE2A, HOXA7, RAD54L, CDC45,SHMT7,MAD2L1,P27,IQGAP3,PTEN,P57,SCAMP3,etc...On the other hand, it is obvious that miR-3200 affects the translational ability of several genes, such as, upregulating GNS,UPRT,EIFAD,YOS1,SGK1,K-Ras,PKM2,C-myc,Pim1,CyclinD1,mTOR,erbB-2,CyclinE,PCNA,RRAS,ARAF,RAPH1,etc.. and down-regulating KDM2A, AATF, TMM17B, RAB8B, MYO1G,P21WAF1/Cip1,GADD45,PTEN,P27,P18,P57,SERBP1,RPL34,UFD1,Bax,ANXA6,GSK3ß. Strikingly, miR-3200 affects some signaling pathway in liver cancer, including carbon metabolism signaling pathway, DNA replication pathway, FoxO signaling pathway, Hippo signaling pathway, serine and threonine metabolism signaling pathway, mTOR signaling pathway, Fatty acid biosynthesis signaling pathway, carcinogenesis-receptor activation signaling pathway, autophagy signaling pathway. Furthermore, our results suggest that miR-3200 enhances expression of RAB7A, and then Rab7A regulates the carcinogenic function of miR-3200 by increasing telomere remodeling in human liver cancer. These results are of great significance for the prevention and treatment of human liver cancer.

Vagal-mAChR4 signaling promotes Friend virus complex (FV)-induced acute erythroleukemia.

Erythroleukemia belongs to acute myeloid leukemia (AML) type 6 (M6), and treatment remains difficult due to the poor prognosis of the disease. Friend virus (FV) is a complex of two viruses: Friend murine leukemia virus (F-MuLV) strain along with a defective spleen focus-forming virus (SFFV), which can induce acute erythroleukemia in mice. We have previously reported that activation of vagal α7 nicotinic acetylcholine receptor (nAChR) signaling promotes HIV-1 transcription. Whether vagal muscarinic signaling mediates FV-induced erythroleukemia and the underlying mechanisms remain unclear. In this study, sham and vagotomized mice were intraperitoneally injected with FV. FV infection caused anemia in sham mice, and vagotomy reversed this change. FV infection increased erythroblasts ProE, EryA, and EryB cells in the spleen, and these changes were blocked by vagotomy. In bone marrow, FV infection reduced EryC cells in sham mice, an effect that was counteracted by vagotomy. FV infection increased choline acetyltransferase (ChAT) expression in splenic CD4+ and CD8+ T cells, and this change was reversed by vagotomy. Furthermore, the increase of EryA and EryB cells in spleen of FV-infected wild-type mice was reversed after deletion of ChAT in CD4+ T cells. In bone marrow, FV infection reduced EryB and EryC cells in sham mice, whereas lack of ChAT in CD4+ T cells did not affect this change. Activation of muscarinic acetylcholine receptor 4 (mAChR4) by clozapine N-oxide (CNO) significantly increased EryB in the spleen but decreased the EryC cell population in the bone marrow of FV-infected mice. Thus, vagal-mAChR4 signaling in the spleen and bone marrow synergistically promotes the pathogenesis of acute erythroleukemia. We uncover an unrecognized mechanism of neuromodulation in erythroleukemia.

miR-624 accelerates the growth of liver cancer cells by inhibiting EMC3.

miRNA is a noncoding RNA found in recent years and more than one third of human genes are the target of miRNAs. miR-624, located on human chromosome 14, is associated with tumorigenesis. However, the role of miR-624 in human hepatocarcinogenesis is still unclear. Herein, our results indicate that miR-624 accelerates the growth of liver cancer cells in vivo and in vitro. Moreover, the modification distribution of H3K9me1 on chromosomes is different between rLV group and rLV-miR-624 group. miR-624 affects epigenetic regulation of several genes in human liver cancer cells, such as RAB21, SMARCD3, MAPK6,PRRX1, ZFHX3, EMC3 (TMEM111). Furthermore, miR-624 affects transcriptome of some genes in liver cancer, including RAB21， UBE2N， PPP1CC，KPNA3， RAB7A，CPEB2,KLF4， MARK2， JUN， ARF6， TMEM39A. On the other hand, miR-624 affects proteome of several genes in liver cancer, such as, RBM5,PTK2, KDM2A,POLR2H, POLR2G,CDK6,KIF15,CUL2,FKBP2,ErbB-3,JUN, PKM2, CyclinE,PLK1, mTOR, PPARγ, Rab7A,ARAF, UPF3B ，PTEN, SUZ12, GADD45, H3.3, CUL5, ARF6,EMC3,ATG4B,ATG14,CALR. Interestingly, miR-624 affects the RAB7A interaction network in liver cancer cells, involving in CLTC，ITGB1，HNRNPU， DARS1， RPS16， CTPS1，H3-3B，JUN,MYH10， CUL5， CPSF7. Strikingly, excessive MEC3 abrogates the carcinogenic functions of miR-624. Importantly, our findings indicate that miR-624 affects some signaling pathway in liver cancer, including Wnt signaling pathway，Hippo signaling pathway，mTOR signaling pathway, Ras signaling pathway，MAPK signaling pathway，PI3K-Akt signaling pathway, erbB signaling pathway. These results provide a basis for the treatment of human liver cancer.

Development and Validation of a Nomogram for Predicting the Risk of Bell's Stage II/III Necrotizing Enterocolitis in Neonates Compared to Bell's Stage I.

Background: Patients with Bell's Stage II/III necrotizing enterocolitis (NEC) may have more severe presentations, higher rates of death, and more long-term complications than those with Bell's Stage I NEC, so the purpose of this article was to construct a nomogram model to distinguish Bell's stage II/III NEC early from Bell's Stage I NEC, which is critical in the clinical management of NEC. Patients and Methods: A total of 730 NEC newborns diagnosed from January 2015 to January 2021 were retrospectively studied. They were randomly divided into training and validation groups at the ratio of 7:3. A nomogram model for predicting NEC was developed based on all the independent risk factors by multivariate regression analysis. The model's performance was mainly evaluated through three aspects: the area under the curve (AUC) to verify discrimination, the Hosmer-Lemeshow test and calibration curve to validate the consistency, and decision curve analysis (DCA) to determine the clinical effectiveness. Results: Predictors included in the prediction model were gestational age (GA), birth weight (BW), asphyxia, septicemia, hypoglycemia, and patent ductus arteriosus (PDA). This nomogram model containing the above-mentioned six risk factors had good discrimination ability in both groups, and the AUCs were 0.853 (95% CI, 0.82-0.89) and 0.846 (95% CI, 0.79-0.90), respectively. The calibration curve and DCA confirmed that the nomogram had good consistency and clinical usefulness. Conclusions: This individual prediction nomogram based on GA, BW, asphyxia, septicemia, hypoglycemia, and PDA served as a useful tool to risk-stratify patients with NEC, and can help neonatologists early distinguish Bell's stage II/III NEC early from Bell's Stage I NEC.

Mast Cell Activation Triggered by Retrovirus Promotes Acute Viral Infection.

Mast cells (MCs) are strategically located at the host-environment interface and their non-allergic roles in the immune-surveillance of pathogens have recently gained more attention. However, MC-caused detrimental regulation of immune inflammations can promote viral invasion. Currently, the role of MCs in retroviral infection remains elusive. We have recently proved that human gut MCs could capture and transfer HIV-1 to CD4+ T cells for promoting viral spread; MC-released histamine augments HIV-1-induced functional polarization of dendritic cells to cause immunosuppression via stimulating the differentiation of regulatory T cells. In this study, we used a murine model of MuLV/Friend virus infection to address MC role in acute retroviral infection in vivo. The acute infection of MuLV/Friend virus could be established in C57BL/6 wild type mice, but viral acquisition showed low efficiency in C57BL/6-Kit W - sh/W - sh (Sash) mice which lack MCs. In mechanism, we found that MuLV/Friend virus triggered MC activation for degranulation; MC degranulation subsequently activated the granulocyte-like myeloid derived suppressive cells (G-MDSCs) to inhibit CD8+ T cells- and NK cells-mediated antiviral immune responses. The reconstruction of MCs in Sash mice promoted acute retroviral infection by regulating G-MDSCs functions and antiviral immune responses. Importantly, the administration of MC stabilizers to block cell degranulation elevated antiviral immune response and consequently suppressed retrovirus infection. This study uncovers a specific role of MCs in acute retroviral infection and elucidates the underlying immune-mechanisms. Targeting MCs may provide a novel approach for controlling acute infection by retroviruses.

Activation of α7 nicotinic acetylcholine receptor promotes HIV-1 transcription.

Alpha7 nicotinic acetylcholine receptor (α7 nAChR), a hub of the cholinergic anti-inflammatory pathway (CAP), is required for the treatment of inflammatory diseases. HIV-1 infection can upregulate the expression of α7 nAChR in T lymphocytes and affect the role of CAP. However, whether α7 nAChR regulates HIV-1 infection in CD4+ T cells is unclear. In this study, we first found that activation of α7 nAChR by GTS-21 (an α7 nAChR agonist) can promote the transcription of HIV-1 proviral DNA. Then, through transcriptome sequencing analysis, we found that p38 MAPK signaling was enriched in GTS-21 treated HIV-latent T cells. Mechanistically, activation of α7 nAChR could increase reactive oxygen species (ROS), reduce DUSP1 and DUSP6, and consequently enhance the phosphorylation of p38 MAPK. By co-immunoprecipitation and liquid chromatography tandem mass spectrometry, we found that p-p38 MAPK interacted with Lamin B1 (LMNB1). Activation of α7 nAChR increased the binding between p-p38 MAPK and LMNB1. We confirmed that knockdown of MAPK14 significantly downregulated NFATC4, a key activator of HIV-1 transcription. Taken together, activation of the α7 nAChR could trigger ROS/p-p38 MAPK/LMNB1/NFATC4 signaling pathway enhancing HIV-1 transcription. We have revealed an unrecognized mechanism of α7 nAChR-mediated neuroimmune regulation of HIV infection.

miR-1307 promotes hepatocarcinogenesis by CALR-OSTC-endoplasmic reticulum protein folding pathway.

miR-1307 is highly expressed in liver cancer and inhibits methyltransferase protein8. Thereby, miR-1307 inhibits the expression of KDM3A and KDM3B and increases the methylation modification of histone H3 lysine 9, which enhances the expression of endoplasmic-reticulum-related gene CALR. Of note, miR-1307 weakens the binding ability of OSTC to CDK2, CDK4, CyclinD1, and cyclinE and enhances the binding ability of CALR to CDK2, CDK4, CyclinD1, and cyclinE, decreasing of p21WAF1/CIP1, GADD45, pRB, and p18, and decreasing of ppRB. Furthermore, miR-1307 increases the activity of H-Ras, PKM2, and PLK1. Strikingly, miR-1307 reduces the binding ability of OSTC to ATG4 and enhances the binding ability of CALR to ATG4. Therefore, miR-1307 reduces the occurrence of autophagy based on ATG4-LC3-ATG3-ATG7-ATG5-ATG16L1-ATG12-ATG9- Beclin1. In particular, miR-1307 enhances the expression of PAK2, PLK1, PRKAR2A, MYBL1, and Trim44 and inhibits the expression of Sash1 and Smad5 via autophagy. Our observations suggest that miR-1307 promotes hepatocarcinogenesis by CALR-OSTC-endoplasmic reticulum protein folding pathway.

CircMEG3 inhibits telomerase activity by reducing Cbf5 in human liver cancer stem cells.

Circular RNA (CircRNA) is a newly identified special class of non-coding RNA (ncRNA) that plays an important regulatory role in the progression of certain diseases. Herein, our results indicate that CircMEG3 is downregulated expression and negatively correlated with the expression of telomerase-related gene Cbf5 in human liver cancer. Moreover, CircMEG3 inhibits the growth of human liver cancer stem cells in vivo and in vitro. CircMEG3 inhibits the expression of m6A methyltransferase METTL3 dependent on HULC. Moreover, CircMEG3 inhibits the expression of Cbf5, a component of telomere synthetase H/ACA ribonucleoprotein (RNP; catalyst RNA pseudouracil modification) through METTL3 dependent on HULC. Thereby, CircMEG3 inhibits telomerase activity and shortens telomere lifespan dependent on HULC and Cbf5 in human liver cancer stem cell. Strikingly, increased Cbf5 abrogates the ability of CircMEG3 to inhibit malignant differentiation of human liver cancer stem cells. In summary, these observations provide important basic information for finding effective liver cancer therapeutic targets.

Long noncoding RNA MEG3 blocks telomerase activity in human liver cancer stem cells epigenetically.

BACKGROUND: MEG3 downregulated the expression in several tumors and inhibits human tumorigenesis. But so far, the mechanism of MEG3 in tumorigenesis is still unclear. METHODS: In gene infection, cellular and molecular technologies and tumorigenesis test in vitro and in vivo were performed, respectively. RESULTS: Our results indicate that MEG3 enhances the P53 expression by triggering the loading of P300 and RNA polymerase II onto its promoter regions dependent on HP1α. Moreover, MEG3 increases the methylation modification of histone H3 at the 27th lysine via P53. Furthermore, MEG3 inhibits the expression of TERT by increasing the H3K27me3 in TERT promoter regions, thereby inhibiting the activity of telomerase by reducing the binding of TERT to TERC. Furthermore, MEG3 also increases the expression of TERRA; therefore, the interaction between TERC and TERT was competitively attenuated by increasing the interaction between TERRA and TERT, which inhibits the activity of telomerase in hLCSCs. Strikingly, MEG3 reduces the length of telomere by blocking the formation of complex maintaining telomere length (POT1-Exo1-TRF2-SNM1B) and decreasing the binding of the complex to telomere by increasing the interplay between P53 and HULC. Ultimately, MEG3 inhibits the growth of hLCSCs by reducing the activity of telomerase and attenuating telomeric repeat binding factor 2(TRF2). CONCLUSIONS: Our results demonstrates MEG3 inhibits the occurrence of human liver cancer by blocking telomere, and these findings provide an important insight into the prevention and treatment of human liver cancer.