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Summary: Epstein-Barr virus (EBV), an oncogenic herpesvirus, is predominantly found in the latent infection form and is highly associated with many human malignancies, which mainly have poor prognoses and no effective treatments. Here, we obtained thirteen compounds from small-molecule libraries for specific inhibition of EBV-latently infected cell growth in vitro by high-throughput screening. Among them, cetrimonium bromide (CetB) was identified to selectively inhibit the growth of different EBV-infected B lymphoma cell lines. Importantly, CetB reduced EBNA1 protein stability, activated G1 arrest and early apoptosis of EBV-latently infected cells without viral lytic reactivation, which leads to dramatically inhibit colony formation and tumor growth of EBV-infected cells in vitro and in vivo, and significantly prolong the survival of tumor-bearing mice. Overall, these findings demonstrate that CetB acts as a highly selective inhibitor of the growth of EBV-infected cells and has the potential for further development of effective therapeutic strategies specific against EBV-associated cancers.

Abstract Despite prolonged surveillance and interventions, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza viruses continue to pose a severe global health burden. Thus, we developed a chimpanzee adenovirus-based combination vaccine, AdC68-HATRBD, with dual specificity against SARS-CoV-2 and influenza virus. When used as a standalone vaccine, intranasal immunization with AdC68-HATRBD induced comprehensive and potent immune responses consisting of immunoglobin (Ig) G, mucosal IgA, neutralizing antibodies, and memory T cells, which protected the mice from BA.5.2 and pandemic H1N1 infections. When used as a heterologous booster, AdC68-HATRBD markedly improved the protective immune response of the licensed SARS-CoV-2 or influenza vaccine. Therefore, whether administered intranasally as a standalone or booster vaccine, this combination vaccine is a valuable strategy to enhance the overall vaccine efficacy by inducing robust systemic and mucosal immune responses, thereby conferring dual lines of immunological defenses for these two viruses.

Abstract Background Helicobacter pylori (H pylori) infection is the primary cause of gastric cancer (GC). The role of Disabled-2 (DAB2) in GC remains largely unclear. This study aimed to investigate the role of DAB2 in H pylori-mediated gastric tumorigenesis. Methods We screened various datasets of GC to analyze DAB2 expression and cell signaling pathways. DAB2 expression was assessed in human GC tissue microarrays. H pylori infection in vivo and in vitro models were further explored. Immunostaining, immunofluorescence, chromatin immunoprecipitation, co-immunoprecipitation, Western blot, quantitative polymerase chain reaction, and luciferase reporter assays were performed in the current study. Results The bioinformatic analysis verified that DAB2 was 1 of the 8 genes contributed to tumorigenesis and associated with poor prognosis in GC. The median overall survival and disease-free survival rates in DAB2high group were significantly less than those in DAB2low group. These findings demonstrated that H pylori transcriptionally activated DAB2 expression via signal transducer and activator of transcription 3 (STAT3)-dependent pathway. By bioinformatics analysis and knockdown or overexpression of DAB2, we found that DAB2 upregulated Yes-associated protein 1 (YAP1) transcriptional activity. Mechanistically, DAB2 served as a scaffold protein for integrin beta 3 (ITGB3) and SRC proto-oncogene non-receptor tyrosine kinase (SRC), facilitated the phosphorylation of SRC, promoted the small GTPase ras homolog family member A (RHOA) activation and phosphorylation of YAP1, and ultimately enhanced the YAP1 transcriptional activity. Conclusions Altogether, these findings indicated that DAB2 is a key mediator in STAT3–regulated translation of YAP1 and plays crucial roles in H pylori-mediated GC development. DAB2 might serve as a novel therapeutic target for GC.

Renal cell carcinoma (RCC) is a frequent urological malignancy characterized by a high rate of metastasis and lethality. The treatment strategy for advanced RCC has moved through multiple iterations over the past three decades. Initially, cytokine treatment was the only systemic treatment option for patients with RCC. With the development of medicine, antiangiogenic agents targeting vascular endothelial growth factor and mammalian target of rapamycin and immunotherapy, immune checkpoint inhibitors (ICIs) have emerged and received several achievements in the therapeutics of advanced RCC. However, ICIs have still not brought completely satisfactory results due to drug resistance and undesirable side effects. For the past years, the interests form researchers have been attracted by the combination of ICIs and targeted therapy for advanced RCC and the angiogenesis and immunogenic tumor microenvironmental variations in RCC. Therefore, we emphasize the potential principle and the clinical progress of ICIs combined with targeted treatment of advanced RCC, and summarize the future direction.

Abstract Background After the eradication of smallpox in China in 1979, vaccination with the vaccinia virus (VACV) Tiantan strain for the general population was stopped in 1980. As the monkeypox virus (MPXV) is rapidly spreading in the world, we would like to investigate whether the individuals with historic VACV Tiantan strain vaccination, even after more than 40 years, could still provide ELISA reactivity and neutralizing protection; and whether the unvaccinated individuals have no antibody reactivity against MPXV at all. Results We established serologic ELISA to measure the serum anti-MPXV titer by using immunodominant MPXV surface proteins, A35R, B6R, A29L, and M1R. A small proportion of individuals (born before 1980) with historic VACV Tiantan strain vaccination exhibited serum ELISA cross-reactivity against these MPXV surface proteins. Consistently, these donors also showed ELISA seropositivity and serum neutralization against VACV Tiantan strain. However, surprisingly, some unvaccinated young adults (born after 1980) also showed potent serum ELISA activity against MPXV proteins, possibly due to their past infection by some self-limiting Orthopoxvirus (OPXV). Conclusions We report the serum ELISA cross-reactivity against MPXV surface protein in a small proportion of individuals both with and without VACV Tiantan strain vaccination history. Combined with our serum neutralization assay against VACV and the recent literature about mice vaccinated with VACV Tiantan strain, our study confirmed the anti-MPXV cross-reactivity and cross-neutralization of smallpox vaccine using VACV Tiantan strain. Therefore, it is necessary to restart the smallpox vaccination program in high risk populations.

Abstract Background A dietary pattern (DP) may impact on cancer incidence more strongly than individual foods, but this association remains uncertain. Here, we aimed to broadly explore the associations of an obesity-related DP with overall and 19 site-specific cancers. Methods This study included 114,289 cancer-free participants with at least two dietary assessments. A total of 210 food items were classified into 47 food groups, and the mean amount of each food group was used in reduced-rank regression to derive the obesity-related DP. Cox regressions were conducted to explore the associations of the obesity-related DP with overall and 19 site-specific cancers. The parallel mediation model was constructed to quantify the mediating roles of potential mediators. Results During a median follow-up period of 9.4 years, 10,145 (8.9%) incident cancer cases were documented. The derived-DP was characterized by a higher intake of beer and cider, processed meat, high sugar beverages, red meat, and artificial sweetener, and a lower intake of fresh vegetables, olive oil, tea, and high fiber breakfast cereals. Observational analysis showed that a higher obesity-related DP Z-score was linearly associated with an increased risk of overall cancer (adjusted hazard ratio (HR) = 1.02, 95% CI: 1.01, 1.04 per 1-SD increase, corrected P

ABSTRACT The covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV) is the major obstacle to curing chronic hepatitis B (CHB). Current cccDNA detection methods are mostly based on biochemical extraction and bulk measurements. They nevertheless generated a general sketch of its biological features. However, an understanding of the spatiotemporal features of cccDNA is still lacking. To achieve this, we established a system combining CRISPR-Tag and recombinant HBV minicircle technology to visualize cccDNA at single-cell level in real time. Using this system, we found that the observed recombinant cccDNA (rcccDNA) correlated quantitatively with its active transcripts when a low to medium number of foci (

Purpose: As the mechanism of interaction between circular RNAs (circRNAs) and microRNAs (miRNAs) in regulating the development of prostate cancer (PCa) is not clear, this study focuses on investigating these effects. Materials and Methods: Sample tissues were collected from the PCa of patients, and microarray analysis of human circRNAs was conducted. The expression of circ_0001686, hsa_miR-411-5p (miR-411-5p) were also detected by qRT-PCR. Circ_0001686 and miR-411-5p mimics were transfected into the PCa cell lines (CWR22RV1and LNCaP) and MTT, colony formation, Transwell, and scratch wound assays were used to analyze the biological behaviors of PCa cells. Si-circ_0001686 and ASO-miR-411-5p were used as negative controls, and dual-luciferase reporter assays were performed to verify the interactions among circ_0001686, miR-411-5p, and SMAD3/TGFBR2. The levels of SMAD3 and TGFBR2 in different treated PCa cells were measured by western blot, and in vivo experiments in a nude mouse model were carried out to strengthen the in vitro findings of miR-411-5p. Results: The expression of circ_0001686 was up-regulated, while the expression of miR-411-5p was down-regulated in PCa cells. Moreover, circ_0001686 promoted cell proliferation, migration, and invasion. Molecular mechanism exploration revealed that circ_0001686 could reduce miR-411-5p, affecting the downstream target genes of SMAD3 and TGFBR2. In vitro and in vivo studies verified that miR-411-5p inhibits PCa progression. Conclusions: Circ_0001686 can reduce miR-411-5p to increase the expression of SMAD3/TGFBR2, which consequently promotes the proliferation, invasion, and migration of PCa cells.

The key structure of the interface between the spike protein of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and human angiotensin-converting enzyme 2 (hACE2) acts as an essential switch for cell entry by the virus and drugs targets. However, this is largely unknown. Here, we tested three peptides of spike receptor binding domain (RBD) and found that peptide 391–465 aa is the major hACE2-interacting sites in SARS-CoV-2 spike RBD. We then identified essential amino acid residues (403R, 449Y, 454R) of peptide 391–465 aa that were critical for the interaction between the RBD and hACE2. Additionally, a pseudotyped virus containing SARS-CoV-2 spike with individual mutation (R454G, Y449F, R403G, N439I, or N440I) was determined to have very low infectivity compared with the pseudotyped virus containing the wildtype (WT) spike from reference strain Wuhan 1, respectively. Furthermore, we showed the key amino acids had the potential to drug screening. For example, molecular docking (Docking) and infection assay showed that Cephalosporin derivatives can bind with the key amino acids to efficiently block infection of the pseudoviruses with wild type spike or new variants. Moreover, Cefixime inhibited live SARS-CoV-2 infection. These results also provide a novel model for drug screening and support further clinical evaluation and development of Cephalosporin derivatives as novel, safe, and cost-effective drugs for prevention/treatment of SARS-CoV-2.

[This corrects the article DOI: 10.1371/journal.ppat.1007416.].

Sex differences in immune responses had been reported to correlate with different symptoms and mortality in the disease course of coronavirus disease 2019 (COVID-19). However, whether severe acute respiratory syndrome coronavirus (SARS-CoV-2) infection interferes with females’ fertility and causes different symptoms among pregnant and non-pregnant females remains unknown. Here, we examined the differences in viral loads, SARS-CoV-2-specific antibody titers, proinflammatory cytokines, and levels of T cell activation after SARS-CoV-2 sub-lethal infection between pregnant and non-pregnant human Angiotensin-Converting Enzyme II (ACE2) transgenic mouse models. Both mice showed elevated levels of viral loads in the lung at 4 days post-infection (dpi). However, viral loads in the pregnant group remained elevated at 7 dpi while decreased in the non-pregnant group. Consistent with viral loads, increased production of proinflammatory cytokines was detected from the pregnant group, and the IgM or SARS-CoV-2-specific IgG antibody in serum of pregnant mice featured delayed elevation compared with non-pregnant mice. Moreover, by accessing kinetics of activation marker expression of peripheral T cells after infection, a lower level of CD8+ T cell activation was observed in pregnant mice, further demonstrating the difference of immune-response between pregnant and non-pregnant mice. Although vertical transmission did not occur as SARS-CoV-2 RNA was absent in the uterus and fetus from the infected pregnant mice, a lower pregnancy rate was observed when the mice were infected before embryo implantation after mating, indicating that SARS-CoV-2 infection may interfere with mice’s fertility at a specific time window. In summary, pregnant mice bear a weaker ability to eliminate the SARS-CoV-2 virus than non-pregnant mice, which was correlated with lower levels of antibody production and T cell activation.

ABSTRACT Hypoxia signaling is a key regulator in the development and progression of many types of human malignancies, including viral cancers. The latency-associated nuclear antigen (LANA), encoded by Kaposi’s sarcoma-associated herpesvirus (KSHV) during latency, is a multifunctional protein that plays an essential role in viral episome maintenance and lytic gene silencing for inducing tumorigenesis. Although our previous studies have shown that LANA contains a SUMO-interacting motif (LANASIM), and hypoxia reduces SUMOylated KAP1 association with LANASIM, the physiological proteomic network of LANASIM-associated cellular proteins in response to hypoxia is still unclear. In this study, we individually established cell lines stably expressing wild-type LANA (LANAWT) and its SIM-deleted mutant (LANAdSIM) and treated them with or without hypoxia, followed by coimmunoprecipitation and mass spectrometry analysis to systemically identify the hypoxia-responsive profile of LANASIM-associated cellular proteins. We found that in hypoxia, the number of cellular proteins associated with LANAWT instead of LANAdSIM was dramatically increased. Functional network analysis revealed that two major pathways, which included cytoskeleton organization and DNA/RNA binding and processing pathways, were significantly enriched for 28 LANASIM-associated proteins in response to hypoxia. HNRNPU was one of the proteins consistently identified that interacted with LANASIM in different proteomic screening systems and responded to hypoxia. This study provides a proteomic profile of LANASIM-associated proteins in hypoxia and facilitates our understanding of the role of the collaboration between viral infection and the hypoxia response in inducing viral persistence and tumorigenesis. IMPORTANCE Kaposi’s sarcoma-associated herpesvirus (KSHV) has been reported to be involved in the regulation of host proteins in response to hypoxic stress. LANA, one of the key latent proteins, contains a SUMO-interacting motif (LANASIM) and reduces the association with SUMOylated KAP1 upon hypoxic treatment. However, the physiological systematic network of LANASIM-associated cellular proteins in hypoxia is still unclear. Here, we revealed two major pathways, which included cytoskeleton organization and DNA/RNA binding and processing pathways, that were significantly enriched for 28 LANASIM-associated proteins in hypoxia. This discovery not only provides a proteomic profile of LANASIM-associated proteins in hypoxia but also facilitates our understanding of the collaboration between viral infection and hypoxic stress in inducing viral persistence and tumorigenesis.

TRIM32 is often aberrantly expressed in many types of cancers. Kaposi’s sarcoma-associated herpesvirus (KSHV) is linked with several human malignancies, including Kaposi’s sarcoma and primary effusion lymphomas (PELs). Increasing evidence has demonstrated the crucial role of KSHV lytic replication in viral tumorigenesis. However, the role of TRIM32 in herpesvirus lytic replication remains unclear. Here, we reveal that the expression of TRIM32 is upregulated by KSHV in latency, and reactivation of KSHV lytic replication leads to the inhibition of TRIM32 in PEL cells. Strikingly, RTA, the master regulator of lytic replication, interacts with TRIM32 and dramatically promotes TRIM32 for degradation via the proteasome systems. Inhibition of TRIM32 induces cell apoptosis and in turn inhibits the proliferation and colony formation of KSHV-infected PEL cells and facilitates the reactivation of KSHV lytic replication and virion production. Thus, our data imply that the degradation of TRIM32 is vital for the lytic activation of KSHV and is a potential therapeutic target for KSHV-associated cancers. IMPORTANCE TRIM32 is associated with many cancers and viral infections; however, the role of TRIM32 in viral oncogenesis remains largely unknown. In this study, we found that the expression of TRIM32 is elevated by Kaposi’s sarcoma-associated herpesvirus (KSHV) in latency, and RTA (the master regulator of lytic replication) induces TRIM32 for proteasome degradation upon viral lytic reactivation. This finding provides a potential therapeutic target for KSHV-associated cancers. [ABSTRACT FROM AUTHOR]

Developing broad-spectrum vaccines and optimal vaccination strategies is crucial to controlling the COVID-19 pandemic. Here, we generated a chimpanzee adenoviral vector-based COVID-19 vaccine carrying broad-spectrum immunogens, modified full-length spike, and conserved T-cell epitopes of SARS-CoV-2, and assessed its immune response in mice through intramuscular (i.m.), intranasal (i.n.), or combined immunization routes (i.m. + i.n., or i.n. + i.m.). Compared to other vaccination strategies, the two combined regimens elicited higher neutralizing antibody (NAb) responses to all variants. Compared to i.n. + i.m. regimen, the i.m. + i.n. regimen stimulated a stronger secondary GC response, which is more pivotal to high-quality antibody production than the primary GC response. Moreover, the i.m. + i.n. regimen was adept at mediating systemic cellular immunity, while the i.n. + i .m. regimen tended to elicit lung tissue-resident memory T (TRM) cell responses. Overall, the two combined regimens induced comprehensive but distinct immune responses consisting of lgA, lgG, NAbs, GC B cells, long-lived plasma cells, TRM cells, and systemic memory T cells, which conferred complete protection against BA.2 infection in hACE2 transgenic mice, and warranted further investigation as potential universal vaccination strategies. IMPORTANCE The development of broad-spectrum SARS-CoV-2 vaccines will reduce the global economic and public health stress from the COVID-19 pandemic. The use of conserved T-cell epitopes in combination with spike antigen that induce humoral and cellular immune responses simultaneously may be a promising strategy to further enhance the broad spectrum of COVID-19 vaccine candidates. Moreover, this research suggests that the combined vaccination strategies have the ability to induce both effective systemic and mucosal immunity, which may represent promising strategies for maximizing the protective efficacy of respiratory virus vaccines. [ABSTRACT FROM AUTHOR]