PubMed Health⌕ Search

Biomedical subjects

Jian Liu

Publications and source records attributed to Jian Liu.

7 recordsLinked to original sources
PubMed2026

E2F7 promotes lung adenocarcinoma progression by affecting phosphorylation and stabilization of β-catenin.

BACKGROUND: E2F transcription factor 7 (E2F7) has been implicated in the tumorigenesis and progression of multiple cancer types; however, the molecular mechanisms through which E2F7 regulates malignant phenotypes in cancer cells remain largely undefined. In this study, we investigated the biological functions and underlying mechanisms of E2F7 in lung adenocarcinoma (LUAD). METHODS: E2F7 expression in LUAD was analyzed using The Cancer Genome Atlas (TCGA) datasets and further validated in clinical specimens via quantitative real-time polymerase chain reaction (PCR) and immunohistochemistry. The effects of E2F7 on cancer cell self‑renewal and epithelial-mesenchymal transition (EMT) were assessed using sphere formation and Transwell assays, respectively. In vivo tumorigenicity and metastasis were evaluated using xenograft models combined with extreme limiting dilution analysis to assess tumor-initiating capacity. Wnt/β‑catenin pathway activity was measured using T-cell factor optimal promoter luciferase reporter plasmid/far-from optimal promoter luciferase reporter plasmid (TOP/FOP) flash reporter assays. β‑Catenin expression, stability, and ubiquitination were examined via western blotting, cycloheximide chase assays, and ubiquitination assays. Protein-protein interactions among E2F7, β‑catenin, and glycogen synthase kinase 3 beta (GSK3β) were verified through co‑immunoprecipitation (Co‑IP), glutathione S‑transferase (GST) pull‑down, and immunofluorescence assays. Truncated mutants were generated to map the functional binding domains of E2F7. In vitro immunoprecipitation and kinase assays were further performed to confirm that E2F7 regulates GSK3β autophosphorylation and β‑catenin phosphorylation. RESULTS: Bioinformatic analyses revealed that E2F7 was significantly upregulated in LUAD tissues, and elevated E2F7 expression correlated with poor patient prognosis. Functional assays demonstrated that E2F7 promoted LUAD cell self‑renewal and EMT. Mechanistically, cytoplasmic E2F7 directly associated with β‑catenin through its DNA‑binding domain (DBD) and PHA03247 domain. E2F7 modulated β‑catenin phosphorylation at Ser675 and Ser33/37/T41, thereby inhibiting ubiquitin‑mediated degradation and enhancing β‑catenin protein stability. Furthermore, E2F7 interacted with GSK3β and suppressed its autophosphorylation at Tyr216, concomitant with reduced β-catenin phosphorylation at Ser33/37/T41 and its accumulation. CONCLUSION: Collectively, these findings indicate that E2F7 drives LUAD malignant progression through regulation of the GSK3β/β‑catenin signaling axis and stabilization of β‑catenin. This study unveils a novel oncogenic mechanism of E2F7 in LUAD and identifies E2F7 as a promising therapeutic target for clinical intervention in LUAD.

E2F7↗
PubMed2026

Unraveling the coastal marine plastisphere archaeome.

Plastic pollution has created an expanding anthropogenic microbial niche, the plastisphere, raising questions about microbial ecology and associated impacts. Archaea, the third domain of life with fundamental ecological and evolutionary significance, remain poorly understood in this habitat. Here, using paired plastic debris and bulk-water samples from coastal marine ecosystems, key archaeal habitats increasingly threatened by plastic pollution, we characterize the plastisphere archaeome through archaeal amplicon sequencing and metagenomics. We show that the archaeome is significantly reshaped in the plastisphere, exhibiting higher taxonomic diversity, greater community heterogeneity, and selective enrichment of Euryarchaeota and Crenarchaeota. Archaeal genes involved in methane, nitrogen, and sulfur cycling are enriched in the plastisphere. Taxonomic and functional divergence between the plastisphere and bulk water increases with anthropogenic chemical stress. These findings suggest that plastic pollution could alter marine archaeal diversity, biogeography, and biogeochemical potential, extending understanding of plastisphere impacts to the archaeal domain.

Archaea↗
PubMed2026

Role of Sanqi Baiji San in Mitigating Ethanol-Induced Gastric Epithelial Cell Injury via PI3K/AKT-related Signaling.

This work aimed to clarify the protective mechanism of Sanqi Baiji San (SQBJ) against ethanol-induced gastric epithelial cell injury and to explore its potential relevance to gastric ulcer (GU). Network pharmacology was used to screen SQBJ's active components (Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform [TCMSP], Oral Bioavailability [OB] ≥ 20%, Drug-Likeness [DL] ≥ 0.1), map their targets (Universal Protein Resource [UniProt]), collect GU-related targets (GeneCards/OMIM/DrugBank), and analyze overlapping targets via Gene Ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment and molecular docking. Ethanol-injured Gastric Epithelial Cell Line-1 (GES-1) cells were treated with SQBJ or the PI3K inhibitor LY294002. CCK-8 was used to determine the optimal SQBJ concentration. Network pharmacology analyses identified 126 common targets enriched within PI3K/AKT/MAPK-related cascades and suggested potential interactions between principal SQBJ constituents and PI3K/AKT-related proteins. In ethanol-challenged cells, SQBJ alleviated cell injury by reducing inflammatory mediator release and oxidative stress, as evidenced by decreased intracellular reactive oxygen species and malondialdehyde levels. SQBJ restored mitochondrial membrane potential and ATP content and reduced apoptosis-associated changes in B-cell lymphoma-2, cleaved caspase-3, and Bcl-2-associated X protein levels. SQBJ also modulated PI3K/AKT- and MAPK-associated signaling markers. These protective effects were largely weakened by LY294002, suggesting that PI3K/AKT-related signaling is involved in SQBJ-mediated cytoprotection. These findings provide an in vitro mechanistic basis for the potential application of SQBJ in GU, although further validation in animal models of ethanol-induced gastric ulcer is required.

Ethanol↗
PubMed2026

Potential evaluation of SULT1A3 as an early diagnostic marker for nasopharyngeal carcinoma: a study based on serum proteomics screening and ELISA validation.

BACKGROUND: Nasopharyngeal carcinoma (NPC) represents a highly prevalent and aggressive malignancy endemic to Southeast Asia. Early and accurate diagnosis is critical to improving survival outcomes; however, the absence of robust, stage-specific biomarkers remains a key obstacle to clinical implementation of early screening strategies. METHODS: We performed untargeted serum proteomic profiling using mass spectrometry in 15 treatment-na&#xef;ve early-stage NPC patients and 15 VCA-IgA-positive healthy controls. Bioinformatics analyses were conducted to identify differentially expressed proteins (DEPs). Machine learning (random forest combined with recursive feature elimination) was employed to prioritize candidate biomarkers, which were subsequently verified using enzyme-linked immunosorbent assay (ELISA) in independent sample cohorts. RESULTS: In total, 1,428 serum proteins were identified, among which 1,410 were reliably quantified. We observed 31 upregulated and 189 downregulated proteins in NPC patients relative to controls. Spearman correlation analysis revealed significant associations: LTA4H (leukotriene A4 hydrolase) levels correlated with serum cell infiltration (r&#x2009;=&#x2009;0.383, p&#x2009;=&#x2009;0.032) and CD8&#x2009;+&#x2009;T-cell abundance (r&#x2009;=&#x2009;0.408, p&#x2009;=&#x2009;0.021); both SULT1A3 (sulfotransferase family 1&#xa0;A member 3) and FGL1 (fibrinogen-like protein 1) levels were positively associated with M1 macrophage infiltration (r&#x2009;=&#x2009;0.510, p&#x2009;=&#x2009;0.003 and r&#x2009;=&#x2009;0.430, p&#x2009;=&#x2009;0.015, respectively). In a preliminary validation cohort (n&#x2009;=&#x2009;80), ELISA yielded AUC values of 0.631 (95% CI: 0.515-0.736, p&#x2009;=&#x2009;0.04) for LTA4H, 0.787 (95% CI: 0.681-0.871, p&#x2009;<&#x2009;0.001) for SULT1A3, and 0.688 (95% CI: 0.575-0.787, p&#x2009;=&#x2009;0.002) for FGL1. In large-scale independent validation, SULT1A3 achieved an AUC of 0.826 (95% CI: 0.766-0.876; sensitivity&#x2009;=&#x2009;78.89%, specificity&#x2009;=&#x2009;75.47%) in cohort 1 (n&#x2009;=&#x2009;196) and 0.796 (95% CI: 0.723-0.857; sensitivity&#x2009;=&#x2009;76.67%, specificity&#x2009;=&#x2009;76.67%) in cohort 2 (n&#x2009;=&#x2009;150). CONCLUSIONS: Through an integrated workflow combining proteomic screening, machine learning prioritization, and multi-stage ELISA validation, we identified SULT1A3 as a candidate serum-based biomarker for early detection of NPC. Preliminary findings suggest that SULT1A3 may have potential utility in clinical screening, though further validation in independent, multi&#x2011;center cohorts is required.

Humans↗
PubMed2025

COG6 is an essential host factor for influenza A virus infection.

Influenza A virus (IAV) relies on the host cellular machinery to support its replication. Understanding these host dependencies can inform the development of novel antiviral strategies. In this study, we identified conserved oligomeric Golgi complex subunit 6 (COG6) as a novel host factor critical for IAV replication through a genome-wide clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) knockout screen. Disruption of COG6 significantly impaired viral replication. Mechanistically, COG6 supports IAV replication via two distinct means. First, consistent with the role of the COG complex in Golgi homeostasis, COG6 is required for the proper presentation of surface sialic acids, the primary receptor for IAV entry. Second, COG6 deficiency unexpectedly led to lysosome-dependent degradation of viral proteins. Notably, lysosomal activity was also upregulated in IAV-infected wild-type cells, albeit to a lesser extent than in COG6-deficient cells. Treatment with lysosomal inhibitors rescued viral protein stability in COG6 knockout cells. Protein interaction analysis further demonstrated that COG6-mediated stabilization of viral proteins did not rely on viral protein-COG6 interaction, refuting the hypothesis that COG6 acts as a shield factor to protect viral protein from lysosomal degradation. Moreover, knockout of other COG subunits produced similar antiviral effects, suggesting that an intact COG complex is required for IAV replication. Together, these findings uncover a critical role of the COG complex in regulating IAV replication and highlight a previously unappreciated functional link between the Golgi and lysosomes that could be exploited for treating IAV infections.IMPORTANCEDespite advances in virology, numerous host determinants facilitating influenza A virus (IAV) pathogenesis remain uncharacterized. Our study establishes conserved oligomeric Golgi complex subunit 6 (COG6) as a critical host factor promoting IAV infection through complementary mechanisms: receptor modulation and viral protein stabilization. This represents the first demonstration that the COG complex regulates viral pathogenesis through proteostasis mechanisms, fundamentally expanding our understanding of host-virus interactions at the organelle interface. These findings not only provide new perspectives on viral exploitation of Golgi trafficking networks but also identify potential therapeutic targets against evolving influenza strains.

Influenza A virus↗
PubMed2025

Comprehensive discovery and functional characterization of the noncanonical proteome.

The systematic identification and functional characterization of noncanonical translation products, such as novel peptides, will facilitate the understanding of the human genome and provide new insights into cell biology. Here, we constructed a high-coverage peptide sequencing reference library with 11,668,944 open reading frames and employed an ultrafiltration tandem mass spectrometry assay to identify novel peptides. Through these methods, we discovered 8945 previously unannotated peptides from normal gastric tissues, gastric cancer tissues and cell lines, nearly half of which were derived from noncoding RNAs. Moreover, our CRISPR screening revealed that 1161 peptides are involved in tumor cell proliferation. The presence and physiological function of a subset of these peptides, selected based on screening scores, amino acid length, and various indicators, were verified through Flag-knockin and multiple other methods. To further characterize the potential regulatory mechanisms involved, we constructed a framework based on artificial intelligence structure prediction and peptide&#x2012;protein interaction network analysis for the top 100 candidates and revealed that these cancer-related peptides have diverse subcellular locations and participate in organelle-specific processes. Further investigation verified the interacting partners of pep1-nc-OLMALINC, pep5-nc-TRHDE-AS1, pep-nc-ZNF436-AS1 and pep2-nc-AC027045.3, and the functions of these peptides in mitochondrial complex assembly, energy metabolism, and cholesterol metabolism, respectively. We showed that pep5-nc-TRHDE-AS1 and pep2-nc-AC027045.3 had substantial impacts on tumor growth in xenograft models. Furthermore, the dysregulation of these four peptides is closely correlated with clinical prognosis. Taken together, our study provides a comprehensive characterization of the noncanonical proteome, and highlights critical roles of these previously unannotated peptides in cancer biology.

Humans↗
PubMed2025

Metagenomic Analysis of the Tonsil Virome Highlights Its Diagnostic Potential for Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is a chronic autoimmune disease whose exact pathogenesis remains unclear, despite links to genetics, environmental factors, and microbial dysbiosis. Recent studies have highlighted the role of the microbiome in RA, yet the contribution of the tonsil virome remains unexplored. This study aims to investigate whether changes in the tonsil virome are associated with RA progression and assess its diagnostic potential. Using metagenomic data from 32 RA patients and 30 healthy controls (HCs), we identified 45&#x2009;782 viral operational taxonomic units (vOTUs), with 14&#x2009;341 classified as core vOTUs. RA patients exhibited significantly reduced virome richness and diversity, whereas Siphoviridae and Microviridae dominated both groups. Statistical analysis identified 235 RA-associated viral markers, including 13 enriched in RA and 222 in HCs. RA-enriched markers were primarily bacteriophages infecting Streptococcaceae, whereas HCs displayed more diverse viral-host interactions. Random forest models demonstrated strong discriminatory power of viral markers in distinguishing RA patients from HCs, achieving an AUC of 0.960, outperforming bacterial markers. Correlation analyses further linked viral markers to immune cell subsets, suggesting that tonsil virome alterations may influence immune dysregulation in RA. This study reveals significant changes in the tonsil virome of RA patients, highlighting its potential as a diagnostic tool and offering new insights into RA pathogenesis. These findings pave the way for future research into the virome's role in autoimmune diseases and therapeutic development.

Humans↗