Occult hepatitis B virus(HBV)infection(OBI)represents a potential reservoir for HBV transmission,capable of spreading through routes such as blood transfusion.Additionally,OBI can con-tribute to the chronic progression of hepatitis B-related diseases,sustaining a state of chronic HBV infec-tion.In individuals with compromised immune function or undergoing immunosuppressive therapy,OBI may lead to HBV re-activation,potentially triggering severe liver conditions such as acute hepatitis or liv-er failure.As a result,OBI poses a significant public health challenge,profoundly impacting the health and well-being of affected populations and complicating HBV infection control efforts in China.Clinically diagnosing OBI remains challenging,but its hallmark is serum hepatitis B surface antigen negative and the presence of HBV covalently closed circular DNA(cccDNA)in the liver.With the increasing focus on achieving functional cure for chronic hepatitis B,both domestic and international guidelines have re-fined functional cure.Notably,these guidelines acknowledge that cccDNA may persist in the liver tissue of individuals who have achieved functional cure,suggesting resemblance of an occult infection state.Here,we provide a comprehensive overview of OBI,including its definition,classification,public health implications,underlying mechanisms,and clinical reactivation.By updating the understanding of OBI,we aim to raise awareness among clinicians and public health professionals regarding the significance of OBI in the current context and encourage greater attention to this population.

With the continuous increase in global obesity prevalence,the impact of obesity on reproduc-tive physiology has garnered widespread societal attention.As a metabolic disorder,obesity is typically accompanied by multiple abnormal physiological phenomena,such as excessive adipose accumulation and exacerbated inflammatory responses,which severely compromise the reproductive health of humans and animals.Reproductive damage induced by obesity involves a series of complex biochemical reactions and in vivo metabolic pathways,manifesting as impaired male sperm quality and female fertility.To better un-derstand the relationship between obesity and reproductive physiology,this review summarizes the repro-ductive injuries caused by obesity and their underlying mechanisms.In the obese state,conditions such as oxidative stress,insulin resistance,and hyperinsulinemia are induced,with adipokines(leptin,adi-ponectin,resistin,etc.)and inflammatory factors(TNF-α,IL-6,IL-1β,etc.)interacting synergisti-cally to affect the reproductive system.Oxidative stress activates the MAPK and NF-κB pathways,inter-fering with insulin signaling,while chronic inflammation leads to adipocyte secretory disorders and dis-rupts the hypothalamic-pituitary-gonadal regulatory axis.Studies have shown that obese males exhibit sig-nificantly decreased testosterone levels and impaired sperm quality,whereas obese females suffer from re-productive hormone imbalance,ovulation disorders,and polycystic ovary syndrome.This review discus-ses how obesity-induced metabolic disorders lead to impaired reproductive physiology in both males and females,along with the underlying mechanisms,providing a theoretical basis for the prevention and treat-ment of obesity-related reproductive disorders in the future.

Ferroptosis,a novel form of programmed cell death driven by iron-dependent lipid peroxida-tion,plays a crucial role in both disease treatment and microbial control due to its multi-level regulatory mechanisms.It mainly involves iron metabolism,lipid peroxidation,and antioxidant systems.In the field of disease treatment,ferroptosis is regarded as a highly promising therapeutic target because of its key role in autoimmune diseases,cancer,and cardiovascular diseases.This review systematically summarizes the core regulatory factors of ferroptosis,such as glutathione peroxidase 4(GPX4)and long-chain acyl-CoA synthetase 4(ACSL4)and their interaction networks,and deeply explores the application prospects of targeted intervention strategies based on ferroptosis signaling pathways in disease treatment and micro-bial control.Additionally,we also summarize the current issues faced by ferroptosis in practical applica-tions and proposes strategies,such as nanodelivery,improved drug chemical stability and enhanced water solubility to optimize therapeutic efficacy.We aim to provide a theoretical basis and practical guidelines for exploring more targeted treatments using ferroptosis.

Breast cancer(BRCA)remains one of the leading causes of cancer-related deaths worldwide due to its high rates of metastasis and recurrence,making it crucial to explore its underlying molecular mechanisms.Our previous study demonstrated that miR-326 inhibits BRCA progression by targeting EPH receptor B3(EPHB3).This study further explores the molecular mechanism by which long non-coding RNAs(LncRNAs)regulates BRCA progression via the competing endogenous RNA(ceRNA)mecha-nism,in which it competes with EPHB3 for miR-326 binding.Bioinformatics analysis identified LncRNA Small Nucleolar RNA Host Gene 12(SNHG12)as a potential miR-326-binding molecule.SNHG12 was found to be significantly upregulated in BRCA tissues,exhibiting a negative correlation trend with miR-326 and a positive correlation trend with EPHB3,suggesting its potential involvement in the ceRNA regu-latory network.Nuclear-cytoplasmic fractionation assays revealed cytoplasmic localization of SNHG12,while dual-luciferase reporter assays confirmed its direct binding to miR-326.Functional experiments demonstrated that SNHG12 knockdown significantly suppressed BRCA cell proliferation,invasion,and migration,while miR-326 inhibition reversed these effects.Furthermore,miRNA pulldown assay re-vealed significant enrichment of SNHG12 and EPHB3 in the miR-326 pulldown products,indicating di-rect binding between them.Western blotting and rescue experiments revealed that SNHG12 upregulates EPHB3 expression by sponging miR-326,thereby promoting the malignant behaviors of BRCA cells.Col-lectively,this study revealed that LncRNA SNHG12 promotes BRCA progression by regulating the miR-326/EPHB3 axis through a ceRNA mechanism.The SNHG12/miR-326/EPHB3 pathway may represent a promising target for the molecular diagnosis and targeted therapy of BRCA.

Gastric cancer remains one of the most prevalent and lethal malignancies of the digestive tract worldwide,underscoring the urgent need for more effective targeted therapeutic strategies.Poly(ADP-ri-bose)polymerase(PARP)inhibitors have demonstrated remarkable efficacy in tumors with homologous recombination repair(HRR)deficiency;however,their clinical application in gastric cancer remains limited.Clinical evidence suggests that patients harboring Helicobacter pylori infection in combination with HRR gene mutations exhibit a significantly elevated risk of developing gastric cancer,thereby supporting the potential benefit of PARP inhibition in this setting.In this study,a kinase inhibitor library was screened in combination with the PARP inhibitor olaparib in gastric cancer cells.And we identify the cy-clin-dependent kinase 8/19(CDK8/19)inhibitor Senexin A as a compound that synergistically enhances the cytotoxic effect of PARP inhibition(P<0.05).Phenotypic validation using CCK-8 and colony for-mation assays demonstrated that the combination treatment significantly suppressed cellular proliferation and clonogenic potential compared to either monotherapy(P<0.0001).Mechanistically,alkaline comet assays revealed a significant increase in DNA damage in the combination treatment group relative to either single-agent group(P<0.0001),suggesting that the synergistic effect results from the exacerbation of DNA damage via impaired DNA repair mechanisms.In addition,treatment with CDK8/19 inhibitors a-lone markedly increased the formation of γH2AX and 53BP1 foci in irradiated gastric cancer cells(P<0.0001),indicating inhibition of DNA damage repair pathways.Transcriptome sequencing further re-vealed that CDK8/19 inhibition impacts critical cellular pathways,including DNA repair,cell cycle reg-ulation,and RNA splicing.Co-immunoprecipitation assays confirmed that inhibition of CDK8/19 kinase activity significantly reduces the phosphorylation level of PARP1,suggesting a potential regulatory inter-action.Immunohistochemical analysis of tumor and adjacent non-tumor tissues from gastric cancer pa-tients demonstrated that CDK8 is significantly overexpressed in tumor tissues,supporting its potential as both a prognostic biomarker and a therapeutic target.Collectively,this study elucidates a mechanistic ba-sis by which CDK8/19 inhibition enhances the sensitivity of gastric cancer cells to PARP inhibitors.These findings provide a strong rationale for the combined use of CDK8/19 and PARP inhibitors as a tar-geted therapeutic strategy and offer promising translational implications for advancing personalized medi-cine in gastric cancer treatment.

Fucoidan(FUC)is a natural seaweed-derived drug.Previously,our experiments have shown that FUC can significantly inhibit the cell viability of human osteosarcoma 143B cells and induce cell death,but the mechanism remains unclear.Ferroptosis,a novel form of cell death,has emerged as an important target for tumor therapy.This study aims to investigate whether FUC induces ferroptosis of 143B cells and elucidate its underlying molecular mechanisms.CCK-8 and LDH assays result showed that FUC(10,100,400 μg/mL)significantly reduced cell viability of 143B cells and induced cell death.Calce-in-AM staining,FeRhoNox-1 staining,and C11 BODIPY 581/591 staining indicated that FUC obviously increased the levels of labile iron pool(LIP),Fe2+,and lipid reactive oxygen species(Lip ROS)in 143B cells.Chemical colorimetric analysis revealed that FUC markedly decreased intracellular Glutathi-one(GSH)contents.Real-time quantitative PCR showed that FUC dramatically reduced the mRNA lev-els of ferroptosis-related factors solute carrier family 7 member 11(SLC7A11)and glutathione peroxidase 4(GPX4),while increasing the mRNA levels of prostaglandin endoperoxide synthase 2(PTGS2)and acyl-CoA synthetase long-chain family member 4(ACSL4).Western blotting analysis demonstrated that FUC significantly reduced the protein levels of SLC7A11 and GPX4,and the ratios of p-PI3K/PI3K,p-AktSer473/Akt,and p-AktThr308/Akt,but increased the protein level of ACSL4.Immunofluorescence staining showed that FUC obviously inhibited the nuclear translocation of p-AktSer473.The ferroptosis in-hibitor ferrostatin-1(Fer-1)and iron chelator deferoxamine(DFO)remarkably suppressed cell death in-duced by FUC in 143B cells.Additionally,the PI3K/Akt pathway activator 740Y-P significantly inhibi-ted FUC-induced iron overload and lipid peroxidation in 143B cells,and restored the protein levels of SLC7A11 and GPX4.In conclusion,FUC can induce ferroptosis of 143B cells by inhibiting the PI3K/Akt signaling pathway,which may be a potential target for the prevention and treatment of osteosarcoma.

The development of tailor-made tumor vaccines targeting specific tumor antigens is crucial for improving treatment accuracy.Tumor mRNA,as an emerging and promising vaccine modality,holds dis-tinct technical edge in addressing this challenge,thus attracting considerable attention in cancer treat-ment.This article reviews the design and synthesis processes of tumor mRNA vaccines,highlighting the latest advances in antigen identification,optimization of RNA sequence and structure,and its delivery.Additionally,it discusses the challenges these vaccines face and outlines potential future directions for development.

Homologous recombination is a crucial biological event during meiosis,and its initial step in-volves the formation of programmed DNA double-strand break(DSB).However,for a long time,how to reconstitute the process of meiotic DSB formation in vitro remained an unresolved challenge in the scien-tific community.Recently,scientists have achieved a breakthrough.For the first time,they successfully reconstructed the formation of meiotic DSB in vitro.The findings reveal that weak dimerization is a key characteristic of the SPO11(sporulation protein11)-TOP6BL(TOP6B like)core complex.In vivo,the activity of SPO11 may be limited by its intrinsically weak dimerization ability.This discovery suggests that the dimerization process of SPO11 plays a vital role in regulating meiotic DSB formation.This a-chievement not only fills a gap in related research fields but also provides critical insights into the molecu-lar mechanism of meiotic DSB formation.Moreover,it offers important directions and implications for fu-ture studies in this field.

Osteosarcoma is a highly aggressive primary bone tumor that predominantly affects children and adolescents.Conventional treatment modalities are often hindered by issues such as high recurrence rates and the development of drug resistance.Proteolysis-Targeting Chimeras(PROTACs)represent an innovative therapeutic strategy for osteosarcoma,which are designed to selectively degrade pathogenic proteins.This article offers a comprehensive analysis of the mechanisms underlying PROTACs,their tar-geted applications in osteosarcoma—including bromodomain and ultra-terminal domain targeting—and the associated challenges,such as delivery efficiency and off-target toxicity.Additionally,it suggests optimi-zation strategies for bone-targeted delivery(such as using DNA nanoflowers as carriers)and combination therapies(like targeted therapy and chemotherapy),informed by recent research findings,thereby provi-ding a theoretical framework for clinical translation.

Diabetes-related cognitive impairment(DCI)is a major complication of type 2 diabetes melli-tus(T2DM).Although exercise is essential in alleviating DCI,the underlying mechanisms remain un-clear.The aim of this study is to investigate the role and mechanism of exosomal miR-126a-5p induced by exercise in ameliorating DCI.Twenty-four 16-week-old male db/db mice were randomly divided into dia-betes group(n=12;DM)and exercise intervention group(n=12;DE).The control group consisted of male m/m mice of the same age group(n=12;CON).The DE group underwent 8 weeks of moderate in-tensity treadmill training(10 m/min,5 days a week).In the MWM experiment,compared to the CON group,the DM group exhibited prolonged escape latency(P<0.01),reduced swimming speed and target quadrant time(P<0.001),and decreased expression of miR-126a-5p and EX-miR-126a-5p in hipp-ocampal tissue(P<0.001).After exercise intervention,the DE group showed improved performance with decreased escape latency(P<0.05),increased swimming speed and target quadrant time(P<0.05),and elevated levels of exosomal miR-126a-5p(P<0.001).Morphological staining revealed a de-crease in the expression and proportion of NeuN in hippocampal neurons and an increase in the expression and proportion of glial cells in the CA1 and CA3 regions of DM group mice compared to CON group mice(P<0.05),while DE group mice showed increased fluorescence intensity and proportion of neurons(P<0.05).Western blotting analysis revealed that the DM group also showed significant upregulation of amy-loid β(Aβ),high mobility group box 1(Hmgb1),and NF-κB in the hippocampus(P<0.05),which were reduced after exercise(P<0.05).Moreover,exosomal miR-126a-5p overexpression greatly de-creased the levels of Hmgb1,NF-κB,and amyloid precursor protein(APP)in HT22 cells and TNF-α,IL-1β in supernatant exposed to HG(P<0.05),while inhibition of miR-126a-5p led to increased levels of these proteins(P<0.05).In conclusion,eight weeks of treadmill exercise improved cognitive function in db/db mice,likely through the EXs-miR-126/HMGB1/NF-κB pathway to reduce inflammation in hip-pocampal tissue.