Autophagy-related protein 5 (ATG5) interacts with bone marrow stromal cell antigen 2 (BST2) to stimulate HBV replication through antagonizing the antiviral activity of BST2.

Hepatitis B virus (HBV) infection is a major global health burden with 820 000 deaths per year. In our previous study, we found that the knockdown of autophagy-related protein 5 (ATG5) significantly upregulated the interferon-stimulated genes (ISGs) expression to exert the anti-HCV effect. However, the regulation of ATG5 on HBV replication and its underlying mechanism remains unclear. In this study, we screened the altered expression of type I interferon (IFN-I) pathway genes using RT² Profiler™ PCR array following ATG5 knock-down and we found the bone marrow stromal cell antigen 2 (BST2) expression was significantly increased. We then verified the upregulation of BST2 by ATG5 knockdown using RT-qPCR and found that the knockdown of ATG5 activated the Janus kinase/signal transducer and activator of transcription (JAK-STAT) signaling pathway. ATG5 knockdown or BST2 overexpression decreased Hepatitis B core Antigen (HBcAg) protein, HBV DNA levels in cells and supernatants of HepAD38 and HBV-infected NTCP-HepG2. Knockdown of BST2 abrogated the anti-HBV effect of ATG5 knockdown. Furthermore, we found that ATG5 interacted with BST2, and further formed a ternary complex together with HBV-X (HBx). In conclusion, our finding indicates that ATG5 promotes HBV replication through decreasing BST2 expression and interacting with it directly to antagonize its antiviral function.

HIF-1α facilitates glioma proliferation and invasion by activating pyroptosis signaling axis.

BACKGROUND: HIF-1α is thought to be a novel regulator which contributes to carcinogenesis. However, the mechanism underlying the effect of HIF-1α in gliomas remains largely unknown. METHODS: In the research, we demonstrate that HIF-lα mRNA and protein levels are elevated in glioma cells. The colony formation assays, transwell assays, and wound-healing assays showed that overexpression of HIF-1α promoted proliferation and invasion of glioma cells. RESULTS: Overexpression of HIF-lα also increased the expression of inflammatory factors related to pyrolysis (TNF-α, IL-10, and IL-1ß) and protein related to pyrolysis signal pathway (NLRP3, ASC, caspase-1, GSDMD, and GSDME). CONCLUSIONS: Therefore, we speculate that HIF-1α promotes the proliferation and invasion of glial cells by regulating pyrolysis pathway. These results might provide a novel strategy and target for treatment of glioma.

Unraveling EGFR-TKI resistance in lung cancer with high PD-L1 or TMB in EGFR-sensitive mutations.

BACKGROUND: Although EGFR-TKI resistance mechanisms in non-small cell lung cancer (NSCLC) have been extensively studied, certain patient subgroups remain with unclear mechanisms. This retrospective study analysed mutation data of NSCLC patients with EGFR-sensitive mutations and high programmed death-ligand 1 (PD-L1) expression or high TMB to identify primary resistance mechanisms. METHODS: Hybrid capture-based next-generation sequencing (NGS) was used to analyse mutations in 639 genes in tumor tissues and blood samples from 339 NSCLC patients. PD-L1 immunohistochemical staining was also performed on the same cell blocks. Molecular and pathway profiles were compared among patient subgroups. RESULTS: TMB was significantly higher in lung cancer patients with EGFR-sensitive mutations and high PD-L1 expression. Compared with the high-expression PD-L1 or high TMB and low-expression or TMB groups, the top 10 genes exhibited differences in both gene types and mutation rates. Pathway analysis revealed a significant mutations of the PI3K signaling pathway in the EGFR-sensitive mutation group with high PD-L1 expression (38% versus 12%, p < 0.001) and high TMB group (31% versus 13%, p < 0.05). Notably, PIK3CA and PTEN mutations emerged as the most important differentially mutated genes within the PI3K signaling pathway. CONCLUSIONS: Our findings reveal that the presence of PI3K signaling pathway mutations may be responsible for inducing primary resistance to EGFR-TKIs in NSCLC patients with EGFR-sensitive mutations along with high PD-L1 expression or high TMB. This finding is of great significance in guiding subsequent precision treatments in NSCLC.

Bacteria-derived nanovesicles enhance tumour vaccination by trained immunity.

Trained immunity enhances the responsiveness of immune cells to subsequent infections or vaccinations. Here we demonstrate that pre-vaccination with bacteria-derived outer-membrane vesicles, which contain large amounts of pathogen-associated molecular patterns, can be used to potentiate, and enhance, tumour vaccination by trained immunity. Intraperitoneal administration of these outer-membrane vesicles to mice activates inflammasome signalling pathways and induces interleukin-1ß secretion. The elevated interleukin-1ß increases the generation of antigen-presenting cell progenitors. This results in increased immune response when tumour antigens are delivered, and increases tumour-antigen-specific T-cell activation. This trained immunity increased protection from tumour challenge in two distinct cancer models.

PPIs therapy has a negative impact on the clinical outcomes of advanced SCLC patients treated with PD-L1 inhibitors.

BACKGROUND: Programmed death-ligand 1 (PD-L1) inhibitors has emerged as a first-line therapeutic strategy for advanced small cell lung cancer (SCLC), which can stimulate T-cell activation, thereby preventing tumor avoidance of immunologic surveillance, whereas, proton pump inhibitors (PPIs) can play an important role in regulating immune function. This study assessed whether the concomitantly use of PPIs affected outcomes of immunotherapy in advanced SCLC. METHODS: Data from advanced SCLC patients who firstly treated with PD-L1 inhibitors between July 2018 and February 2021 was retrospectively analyzed. The impact of concomitant medications (especially PPIs) on objective response rate, progression-free survival (PFS) and overall survival (OS) were evaluated. RESULTS: Of 208 patients, 101 received immunotherapy concomitant PPIs. The median PFS of patients receiving PPIs (6.6 months) were significantly shorter than those without PPIs (10.6 months), and so was OS. There was associated with a 74.9% increased risk of progression and 58.3% increased risk of death. Both first-line and post-first-line immunotherapy, patients treated PPIs had poorer PFS. CONCLUSION: PPIs therapy has a negative impact on the clinical outcomes of advanced SCLC patients treated with PD-L1 inhibitors.

Classification models for Tobacco Mosaic Virus and Potato Virus Y using hyperspectral and machine learning techniques.

Tobacco Mosaic Virus (TMV) and Potato Virus Y (PVY) pose significant threats to crop production. Non-destructive and accurate surveillance is crucial to effective disease control. In this study, we propose the adoption of hyperspectral and machine learning technologies to discern the type and severity of tobacco leaves affected by PVY and TMV infection. Initially, we applied three preprocessing methods - Multivariate Scattering Correction (MSC), Standard Normal Variate (SNV), and Savitzky-Golay smoothing filter (SavGol) - to corrected the leaf full-length spectral sheet data (350-2500nm). Subsequently, we employed two classifiers, support vector machine (SVM) and random forest (RF), to establish supervised classification models, including binary classification models (healthy/diseased leaves or PVY/TMV infected leaves) and six-class classification models (healthy and various severity levels of diseased leaves). Based on the core evaluation index, our models achieved accuracies in the range of 91-100% in the binary classification. In general, SVM demonstrated superior performance compared to RF in distinguishing leaves infected with PVY and TMV. Different combinations of preprocessing methods and classifiers have distinct capabilities in the six-class classification. Notably, SavGol united with SVM gave an excellent performance in the identification of different PVY severity levels with 98.1% average precision, and also achieved a high recognition rate (96.2%) in the different TMV severity level classifications. The results further highlighted that the effective wavelengths captured by SVM, 700nm and 1800nm, would be valuable for estimating disease severity levels. Our study underscores the efficacy of integrating hyperspectral technology and machine learning, showcasing their potential for accurate and non-destructive monitoring of plant viral diseases.

Experiences and requirements in nutritional management of patients with esophageal cancer: a systematic review and qualitative meta-synthesis.

PURPOSE: Nutritional management of patients with esophageal cancer is a significant issue. This systematic review aimed to comprehensively synthesize qualitative research evidence on the experiences and requirements in nutritional management from the perspective of patients with esophageal cancer. METHODS: A systematic review and meta-synthesis of qualitative studies were conducted. Studies written in Chinese or English were retrieved from nine databases, namely, PubMed, Web of Science, Cochrane Library, CINAHL, Embase, CNKI, WanFang, VIP, and SinoMed, from inception to December 23, 2022. After screening the titles, abstracts, and full texts, 19 articles were finally included for quality assessment and meta-synthesis. RESULTS: Three comprehensive themes were derived. These were dietary experiences (perception of symptoms and dietary behaviors), emotional experiences (negative and positive emotions), and social support (inappropriate social support and inadequate nutritional management). CONCLUSIONS: The experiences and requirements of esophageal cancer patients in terms of nutritional management during treatment and rehabilitation were reviewed and factors influencing nutritional management were discussed. The findings suggested that medical institutions should expedite the development of comprehensive nutritional management systems, create conducive nutritional environmental facilities, and establish interdisciplinary teams to implement personalized comprehensive interventional models for the management of patient nutrition. These steps would maximize the effectiveness of nutritional therapy, promote early patient recovery, and bridge the gap between healthcare professionals and patients in the understanding of nutritional management.

Vacuum sealing drainage combined with eggshell-like debridement antibiotic-loaded calcium sulphate for calcaneal osteomyelitis.

BACKGROUND: To compare the clinical efficacy of vacuum sealing drainage, eggshell-like debridement combined with antibiotic calcium sulphate implantation and conventional debridement combined with antibiotic calcium sulphate implantation in the treatment of calcaneal osteomyelitis. METHODS: Sixty-six patients with calcaneal osteomyelitis who were treated in our department between January 2017 and August 2021 were included in this study. Thirty-one patients underwent VSD and eggshell-like debridement combined with antibiotic calcium sulphate implantation. Thirty-five patients underwent conventional debridement combined with antibiotic calcium sulphate implantation. The inflammatory markers, operation time, wound healing time, hospital stay, full weight bearing time after operation, recurrence rate of infection, complications, and American Orthopedic Foot and Ankle Society (AOFAS) scores were compared between the two groups. RESULTS: The operation time and full weight bearing time after operation of observation group were longer than that of control group. Compared with preoperative results, WBC, ESR, CRP and PCT in both groups were significantly decreased at 14 days after operation, and there was no statistical significance between the two groups. The wound healing time and hospital stay in the observation group were shorter than those in the control group (P < 0.05). There were four patients with aseptic exudation in the observation group and ten patients with aseptic exudation in the control group, and the wounds healed well after multiple dressing changes. Seven patients in the observation group underwent secondary bone grafting due to bone defects, and four patients in the control group received secondary bone grafting due to bone defects. In the observation group, three patients received debridement combined with antibiotic calcium sulphate implantation again due to recurrent infection, compared with seven patients in the control group. One year after operation, the observation group had a better AOFAS scores than the control group, especially in terms of foot function (P < 0.05). CONCLUSION: Compared with conventional debridement and antibiotic calcium sulphate implantation, VSD and eggshell-like debridement combined with antibiotic calcium sulphate implantation in the treatment of calcaneal osteomyelitis can shorten the wound healing and hospital stay of patients, reduce postoperative aseptic exudation complications and infection recurrence rate, and better preserve the foot function, which is a simple and effective method.

Allicin Alleviates Mitochondrial Dysfunction in Acrylamide-Induced Rat Kidney Involving the Regulation of SIRT1.

Acrylamide (AA), commonly formed in carbohydrate-rich thermally processed foods, exerts harmful effects on the kidney. Allicin, from crushed garlic cloves, exhibits strong biological activities. In the current study, the protection mechanisms of allicin against AA-caused nephrotoxicity were comprehensively examined using an in vivo rat model based on previous research that allicin plays a key role in improving renal function. The results showed that allicin attenuated histological changes of the kidney and ameliorated renal function. Damaged mitochondrial structures, upregulated voltage-dependent anion channel 1 expression, and decreased membrane potential and adenosine 5'-triphosphate levels were observed after AA treatment. Surprisingly, allicin notably reversed the adverse effects. Further, allicin effectively restored mitochondrial function via modulating mitochondrial biogenesis and dynamics, which might be associated with the upregulated expression of sirtuin 1 (SIRT1). Meanwhile, allicin dramatically activated the SIRT1 activity and subsequently inhibited p53 acetylation, prevented the translocation of cytochrome c to the cytoplasm, and reduced the caspase expression, thus further inhibiting mitochondrial apoptosis caused by AA. In summary, the relieving effect of allicin on AA-caused nephrotoxicity lies in its inhibition of mitochondrial dysfunction and mitochondrial apoptosis.

Intelligent Responsive Nanoparticles with Multilevel Triggered Drug Penetration for Tumor Photochemotherapy.

Nanomedicines have contradictory size requirements to overcome systemic barriers and penetrate the tumor extracellular matrix (ECM). Larger-sized nanoparticles (50-200 nm) exhibit prolonged blood circulation half-life and improved tumor enrichment, while small-sized nanoparticles (4-20 nm) easily penetrate deep tumor tissues. Therefore, the development of intelligent responsive nanomedicine systems can not only increase nanodrug tumor accumulation but also improve their penetration into the ECM. Herein, we propose an intelligent responsive nanoparticle triggered by near-infrared light (NIR). The nanoparticle was constructed by a temperature-sensitive liposome (TSL) encapsulating ultrasmall melanin nanoparticles (MNPs) loaded with doxorubicin (MNP/doxorubicin (DOX)@TSL). When exposed to NIR irradiation, the tailor-made nanoparticles not only effectively ablated the tumor cells around blood vessels but also destroyed the structural integrity and released loaded ultrasmall MNP/DOX (<10 nm) to promote deep tumor penetration and enhance interior tumor cell killing. This NIR-triggered intelligent nanoparticle successfully integrated photothermal therapy (PTT) for perivascular tumor cells and chemotherapy for deep tumor cell inhibition. The in vivo results showed remarkable tumor regression in 4T1 breast tumor-bearing mice by 74.2%. This controllable size switchable nanosystem with efficient tumor accumulation and penetration has shown great potential in improving synergistic antitumor effects of photochemotherapy.

Construction of a Delivery Platform for Vaccine Based on Modified Nanotubes: Sustainable Prevention against Plant Viral Disease, Simplified Preparation Method, and Protection of Plasmid.

Control of plant viral diseases through cross-protection conferred by an attenuated vaccine is an important strategy for plant protection. However, the mutated site of an attenuated vaccine may not be stably inherited, while viruses have evolved efficient repair mechanisms for the maintenance of genomic integrity. Here, the wide host range and broad selection of mutation sites in cucumber mosaic virus (CMV) enabled construction of an attenuated vaccine through insertional mutation of the CMV 2b protein. CMV-R2E was stably inherited in tobacco for more than 10 generations and had a high relative control efficacy of CMV. Then, the use of polyetherimide (PEI)-modified functionalized carboxylated single-walled carbon nanotubes (PSWNTs) was investigated for vaccine delivery to address the problems of poor stability, complex procedure on field application, and exacting storage conditions with Agrobacterium inoculation. After co-incubating at a 1:300 ratio for 30 min, the vaccine and PSWNTs combined to form pCMV-R2E@PSWNTs, which resulted in a significant increase in the average height of the nanoparticles from 6.56 to 72.34 nm. The relative control efficacy of pCMV-R2E@PSWNTs to CMV was found to be 90.37%. Furthermore, the protective effect of PSWNTs on plasmids was investigated under various environmental conditions and the potential plant toxicity of pCMV-R2E@PSWNTs was assessed, providing a theoretical basis for field application of the vaccine nano-delivery system. A highly effective, stable viral vaccine for plants was thus developed and combined with nanocarriers to address the problems of field application. This approach has the potential to enable wider use of attenuated vaccines for sustainable prevention against plant viral disease in the field.

Outer Membrane Vesicle-Based Nanohybrids Target Tumor-Associated Macrophages to Enhance Trained Immunity-Related Vaccine-Generated Antitumor Activity.

Trained immunity refers to the innate immune system building memory-like features in response to subsequent infections and vaccinations. Compared with classical tumor vaccines, trained immunity-related vaccines (TIrV) are independent of tumor-specific antigens. Bacterial outer membrane vesicles (OMVs) contain an abundance of PAMPs and have the potential to act as TIrV-inducer, but face challenges in endotoxin tolerance, systemic delivery, long-term training, and trained tumor-associated macrophage (TAM)-mediated antitumor phagocytosis. Here, an OMV-based TIrV is developed, OMV nanohybrids (OMV-SIRPα@CaP/GM-CSF) for exerting vaccine-enhanced antitumor activity. In the bone marrow, GM-CSF-assisted OMVs train bone marrow progenitor cells and monocytes, which are inherited by TAMs. In tumor tissues, SIRPα-Fc-assisted OMVs trigger TAM-mediated phagocytosis. This TIrV can be identified by metabolic and epigenetic rewiring using transposase-accessible chromatin (ATAC) and transcriptome sequencing. Furthermore, it is found that the TIrV-mediated antitumor mechanism in the MC38 tumor model (TAM-hot and T cell-cold) is trained immunity and activated T cell response, whereas in the B16-F10 tumor model (T cell-hot and TAM-cold) is primarily mediated by trained immunity. This study not only develops and identifies OMV-based TIrV, but also investigates the trained immunity signatures and therapeutic mechanisms, providing a basis for further vaccination strategies.

Biotransformation of triterpenoid ganoderic acids from exogenous diterpene dihydrotanshinone I in the cultures of Ganoderma sessile.

BACKGROUND: Triterpenoids have shown a wide range of biological activities including antitumor and antiviral effects. Typically, triterpenes are synthesized through the mevalonate pathway and are extracted from natural plants and fungi. In this work, triterpenoids, ganoderic acids (GAs) were discovered to be produced via biotransformation of a diterpene, 15,16-dihydrotanshinone I (DHT) in the liquid cultured Ganoderma sessile mycelium. RESULTS: Firstly, the biotransformation products, two rare GAs were isolated and purified by column chromatography, and characterized using HR-ESI-MS spectrometry and NMR spectrometry. The two compounds were Lanosta-7,9(11),24-trien-15α,22,ß-diacetoxy-3ß-hydroxy-26-oic acid (LTHA) and Lanosta-7,9(11),24-trien-15α,22,ß-diacetoxy-3ß-carbonyl-26-oic acid (LTCA). Then, transcriptome and proteome technologies were employed to measure the expression of mRNA and protein, which further confirmed that triterpenoid GAs could be transformed from exogenous diterpenoid DHT. At the molecular level, we proposed a hypothesis of the mechanism by which DHT converted to GAs in G. sessile mycelium, and the possible genes involved in biotransformation were verified by RT-qPCR. CONCLUSIONS: Two rare GAs were obtained and characterized. A biosynthetic pathway of GAs from DHT was proposed. Although the synthetic route was not confirmed, this study provided important insights into omics resources and candidate genes for studying the biotransformation of diterpenes into triterpenes.

Lack of surgical resection is associated with increased early mortality in hematological patients complicated with rhino-orbital-cerebral mucormycosis.

Rhino-orbital-cerebral mucormycosis (ROCM), which is an acute fatal infectious disease with a high mortality rate, is increasingly being diagnosed in patients with hematological diseases worldwide. We aimed to investigate the clinical characteristics, treatment, and prognosis of hematological diseases complicated by ROCM. Our sample comprised a total of 60 ROCM patients with hematological diseases. The most common primary disease was acute lymphoblastic leukemia (ALL) (n=27, 45.0%), while 36 patients (60.0%) were diagnosed with a clear type of pathogen, all belonging to the Mucorales, most commonly Rhizopus (41.7%). Of the 32 patients (53.3%) who died, 19 (59.3%) died of mucormycosis, and 84.2% (n=16) of those died within 1 month. Forty-eight cases (80.0%) received antifungal treatment combined with surgical therapy, 12 of whom (25.0%) died of mucormycosis, amounting to a mortality rate that was significantly lower than in patients who received antifungal therapy alone (n=7, 58.3%) (P=0.012). The median neutrophil value of patients who underwent surgery was 0.58 (0.11-2.80) 103/µL, the median platelet value was 58.00 (17.00-93.00) 103/µL, and no surgery-related deaths were reported. Multivariate analysis showed that patient's advanced age (P=0.012, OR=1.035 (1.008-1.064)) and lack of surgical treatment (P=0.030, OR=4.971 (1.173-21.074)) were independent prognostic factors.In this study, hematological diseases associated with ROCM have a high mortality rate. Lack of surgical treatment is an independent prognostic factor for death from mucormycosis. Surgery may therefore be considered in patients with hematological disease even if their neutrophil and platelet values are lower than normal.

Deciphering the rhizosphere bacteriome associated with biological control of tobacco black shank disease.

Introduction: The black shank disease seriously affects the health of tobacco plants. Conventional control methods have limitations in terms of effectiveness or economic aspects and cause public health concerns. Thus, biological control methods have come into the field, and microorganisms play a key role in suppressing tobacco black shank disease. Methods: In this study, we examined the impact of soil microbial community on black shank disease basing on the structural difference of bacterial communities in rhizosphere soils. We used Illumina sequencing to compare the bacterial community diversity and structure in different rhizosphere soil samples in terms of healthy tobacco, tobacco showing typical black shank symptoms, and tobacco treated with the biocontrol agent, Bacillus velezensis S719. Results: We found that Alphaproteobacteria in the biocontrol group, accounted for 27.2% of the ASVs, was the most abundant bacterial class among three groups. Heatmap and LEfSe analyses were done to determine the distinct bacterial genera in the three sample groups. For the healthy group, Pseudomonas was the most significant genus; for the diseased group, Stenotrophomonas exhibited the strongest enrichment trend, and Sphingomonas showed the highest linear discriminant analysis score, and was even more abundant than Bacillus; for the biocontrol group, Bacillus, and Gemmatimonas were the largely distributed genus. In addition, co-occurrence network analysis confirmed the abundance of taxa, and detected a recovery trend in the network topological parameters of the biocontrol group. Further functional prediction also provided a possible explanation for the bacterial community changes with related KEGG annotation terms. Discussion: These findings will improve our knowledge of plant-microbe interactions and the application of biocontrol agents to improve plant fitness, and may contribute to the selection of biocontrol strains.

Nanoscale Organization of TRAIL Trimers using DNA Origami to Promote Clustering of Death Receptor and Cancer Cell Apoptosis.

Through inducing death receptor (DR) clustering to activate downstream signaling, tumor necrosis factor related apoptosis inducing ligand (TRAIL) trimers trigger apoptosis of tumor cells. However, the poor agonistic activity of current TRAIL-based therapeutics limits their antitumor efficiency. The nanoscale spatial organization of TRAIL trimers at different interligand distances is still challenging, which is essential for the understanding of interaction pattern between TRAIL and DR. In this study, a flat rectangular DNA origami is employed as display scaffold, and an "engraving-printing" strategy is developed to rapidly decorate three TRAIL monomers onto its surface to form DNA-TRAIL3 trimer (DNA origami with surface decoration of three TRAIL monomers). With the spatial addressability of DNA origami, the interligand distances are precisely controlled from 15 to 60 nm. Through comparing the receptor affinity, agonistic activity and cytotoxicity of these DNA-TRAIL3 trimers, it is found that ≈40 nm is the critical interligand distance of DNA-TRAIL3 trimers to induce death receptor clustering and the resulting apoptosis.Finally, a hypothetical "active unit" model is proposed for the DR5 clustering induced by DNA-TRAIL3 trimers.

Site-Specific Modification of Virus-Like Particles for Exogenous Tumor Antigen Display and Minimizing Preexisting Immunity.

The widespread preexisting immunity against virus-like particles (VLPs) seriously limits the applications of VLPs as vaccine vectors. Enabling technology for exogenous antigen display should not only ensure the assembly ability of VLPs and site-specific modification, but also consider the effect of preexisting immunity on the behavior of VLPs in vivo. Here, combining genetic code expansion technique and synthetic biology strategy, a site-specific modification method for hepatitis B core (HBc) VLPs via incorporating azido-phenylalanine into the desired positions is described. Through modification position screening, it is found that HBc VLPs incorporated with azido-phenylalanine at the main immune region can effectively assemble and rapidly conjugate with the dibenzocycolctyne-modified tumor-associated antigens, mucin-1 (MUC1). The site-specific modification of HBc VLPs not only improves the immunogenicity of MUC1 antigens but also shields the immunogenicity of HBc VLPs themselves, thereby activating a strong and persistent anti-MUC1 immune response even in the presence of preexisting anti-HBc immunity, which results in the efficient tumor elimination in a lung metastatic mouse model. Together, these results demonstrate the site-specific modification strategy enabled HBc VLPs behave as a potent antitumor vaccine and this strategy to manipulate immunogenicity of VLPs may be suitable for other VLP-based vaccine vectors.

Identification and validation of ferroptosis-related genes in patients infected with dengue virus: implication in the pathogenesis of DENV.

Ferroptosis, an iron-dependent form of regulated cell death, has been associated with many virus infections. However, the role of ferroptosis in dengue virus (DENV) infection remains to be clarified. In our study, a dengue fever microarray dataset (GSE51808) of whole blood samples was downloaded from the Gene Expression Omnibus (GEO), and a list of ferroptosis related genes (FRGs) was extracted from the FerrDb. We identified 37 ferroptosis-related differentially expressed genes (FR-DEGs) in DENV-infected patient blood samples compared to healthy individuals. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses as well as protein-protein interaction (PPI) network of FR-DEGs revealed that these 37 FR-DEGs were mainly related to the C-type lectin receptor and p53 signaling pathway. Nine out of the 37 FR-DEGs (HSPA5, CAV1, HRAS, PTGS2, JUN, IL6, ATF3, XBP1, and CDKN2A) were hub genes, of which 5 were validated by qRT-PCR in DENV-infected HepG2 cells. Finally, using miRNA-mRNA regulatory network, we identified has-miR-124-3p and has-miR-16-5p as the most critical miRNAs in regulating the expression of these hub genes. In conclusion, our findings demonstrated that 5 FR-DEGs, JUN, IL6, ATF3, XBP1, and CDKN2A, and two miRNAs, has-miR-124-3p and has-miR-16-5p may implicate an essential role of ferroptosis in DENV infection, and further studies are warranted to explore the underlying mechanisms.

Diversity and Evolution of Iron Uptake Pathways in Marine Cyanobacteria from the Perspective of the Coastal Strain Synechococcus sp. Strain PCC 7002.

Marine cyanobacteria contribute to approximately half of the ocean primary production, and their biomass is limited by low iron (Fe) bioavailability in many regions of the open seas. The mechanisms by which marine cyanobacteria overcome Fe limitation remain unclear. In this study, multiple Fe uptake pathways have been identified in a coastal strain of Synechococcus sp. strain PCC 7002. A total of 49 mutants were obtained by gene knockout methods, and 10 mutants were found to have significantly decreased growth rates compared to the wild type (WT). The genes related to active Fe transport pathways such as TonB-dependent transporters and the synthesis and secretion of siderophores are found to be essential for the adaptation of Fe limitation in Synechococcus sp. PCC 7002. By comparing the Fe uptake pathways of this coastal strain with other open-ocean cyanobacterial strains, it can be concluded that the Fe uptake strategies from different cyanobacteria have a strong relationship with the Fe bioavailability in their habitats. The evolution and adaptation of cyanobacterial iron acquisition strategies with the change of iron environments from ancient oceans to modern oceans are discussed. This study provides new insights into the diversified strategies of marine cyanobacteria in different habitats from temporal and spatial scales. IMPORTANCE Iron (Fe) is an important limiting factor of marine primary productivity. Cyanobacteria, the oldest photosynthetic oxygen-evolving organisms on the earth, play crucial roles in marine primary productivity, especially in the oligotrophic ocean. How they overcome Fe limitation during the long-term evolution process has not been fully revealed. Fe uptake mechanisms of cyanobacteria have been partially studied in freshwater cyanobacteria but are largely unknown in marine cyanobacterial species. In this paper, the characteristics of Fe uptake mechanisms in a coastal model cyanobacterium, Synechococcus sp. PCC 7002, were studied. Furthermore, the relationship between Fe uptake strategies and Fe environments of cyanobacterial habitats has been revealed from temporal and spatial scales, which provides a good case for marine microorganisms adapting to changes in the marine environment.