Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by immune dysregulation and cellular metabolic abnormalities, including enhanced glycolytic activity in CD4+ T cells. However, the molecular regulators that link metabolic alterations to aberrant CD4+ T cell responses remain incompletely understood. We integrated bulk RNA sequencing (RNA-seq) datasets from peripheral blood mononuclear cells (PBMCs) of SLE patients with a set of glycolysis- and lactate metabolism-related genes (GALMRGs) to prioritize candidate metabolic regulators. Candidate genes were then evaluated in independent bulk RNA-seq, single-cell RNA sequencing (scRNA-seq), and purified CD4+ T cell datasets, among which ENO1 emerged as a leading hit. To investigate its role in CD4+ T cell function, we performed in silico perturbation analysis and validated predictions using clinical samples and in vitro experiments in human and murine CD4+ T cells. ENO1 was reproducibly upregulated across multiple independent cohorts and emerged as the top candidate. scRNA-seq revealed elevated GALMRG scores in CD4+ T cells from SLE patients. In silico perturbation linked ENO1 to T-cell activation programs, and experimental ENO1 knockdown altered the expression of activation-related genes, including CCR7, IL7R, JUNB, and AIF1. At the protein level, ENO1 was elevated in PBMCs and CD4+ T cells from SLE patients, and ENO1 expression in CD4+ T cells correlated positively with SLE Disease Activity Index (SLEDAI) scores. Functionally, ENO1 inhibition suppressed proliferation of both human and murine CD4+ T cells, and ENO1 knockdown reduced glucose uptake and intracellular lactate levels in activated murine CD4+ T cells. Molecular docking identified Barasertib and CC_401 as candidate ENO1-interacting compounds, providing a computational basis for future validation. This study identifies ENO1 as a glycolysis- and lactate metabolism-associated factor associated with CD4+ T cell function in SLE and offers a resource for further mechanistic investigation of glycolysis and lactate metabolism in the disease.
Hepatocellular carcinoma (HCC) is a malignant tumor with high mortality worldwide. Abnormalities in the ubiquitin proteasome system are considered to contribute to HCC progression. DDB1 and CUL4 associated factor 13 (DCAF13) is a substrate receptor of the E3 ubiquitin ligase CRL4, but its role and downstream substrates in HCC have not been fully elucidated. In this study, we aimed to investigate the regulatory mechanisms of DCAF13 in HCC. Our results demonstrated that DCAF13 was significantly upregulated in HCC tissues and cell lines, and its high expression was correlated with advanced TNM stage and poor overall survival. Functionally, DCAF13 knockdown inhibited HCC cell proliferation, colony formation, and migration, and promoted cell apoptosis in vitro. Knockdown of DCAF13 also suppressed tumor growth in vivo. Through RNA-sequencing, we found that DCAF13 positively regulated the calcium signaling pathway. Mechanistically, we demonstrated that DCAF13 directly binds to RCAN1.4, promotes its ubiquitination and proteasomal degradation. Lower RCAN1.4 levels were associated with a reduction in its inhibitory effect on calcineurin, in which were associated with NFAT1 nuclear accumulation. These findings suggest that DCAF13 promotes HCC progression, at least in part, by facilitating RCAN1.4 ubiquitination and degradation, and contributing to calcium signaling alterations. Accordingly, DCAF13 may serve as a potential biomarker and therapeutical target for HCC.
Vascular cell adhesion molecule-1 (VCAM-1) has been implicated in tumor progression, but its role and molecular mechanisms in colorectal cancer (CRC) remain incompletely defined. This study investigated the clinical association and functional mechanisms of VCAM-1 in CRC. Immunohistochemistry using a tissue microarray containing 90 CRC samples showed that VCAM-1 expression was higher in CRC tissues than in adjacent non-tumorous tissues. Reanalysis of the original survival dataset showed that VCAM-1 positivity was associated with better overall survival in this cohort, whereas its associations with most clinicopathological variables were not statistically significant. This survival association should be interpreted cautiously and requires validation in larger independent cohorts. In vitro, VCAM-1 knockdown in HCT116 and SW480 cells suppressed proliferation, migration, and invasion and promoted apoptosis. Mechanistically, VCAM-1 depletion inhibited RhoA/LIMK/Cofilin signaling, reduced F-actin organization and fluorescence intensity, and reversed epithelial-mesenchymal transition (EMT)-related changes; RhoA-Q63L expression partially restored downstream signaling, cytoskeletal organization, migration, and invasion. VCAM-1 also contributed to CRC cell adhesion to endothelial cells and migration in an M2 macrophage co-culture setting. In vivo, stable VCAM-1 knockdown in HCT116 cells reduced tumor growth in a subcutaneous model. In a tail-vein BLI model, the same knockdown decreased whole-body experimental colonization burden. Together, these findings suggest that VCAM-1 may promote CRC cell progression through RhoA/LIMK/Cofilin-related cytoskeletal remodeling and tumor microenvironment-associated interactions. However, the clinical prognostic direction observed in the current cohort differs from the tumor-promoting functional findings, and the prognostic and therapeutic relevance of VCAM-1 should be further evaluated in larger studies.
Excessive inflammation contributes to adverse cardiac remodeling after myocardial infarction (MI), but the mechanisms linking cardiomyocyte injury to immune activation remain incompletely understood. Here, we investigated the role of the endoplasmic reticulum chaperone HSP90B1 in cardiomyocyte injury and inflammatory crosstalk after MI. We examined HSP90B1 expression in human myocardial tissues, mouse MI hearts, and oxygen-glucose deprivation (OGD)-treated AC16 cardiomyocytes. Hsp90b1+/− mice were used to evaluate post-MI survival, cardiac function, and myocardial remodeling. HSP90B1 was selectively silenced or overexpressed in AC16 cardiomyocytes, and transcriptomic and pharmacological analyses were performed to investigate the signaling pathways involved. A non-contact Transwell co-culture system was also established to assess the effects of cardiomyocyte HSP90B1 on macrophage inflammatory activation. HSP90B1 was increased in human and mouse myocardial tissues after MI and in OGD-treated AC16 cardiomyocytes. Hsp90b1+/− mice showed improved post-MI survival, preserved cardiac function, and reduced adverse remodeling. In AC16 cardiomyocytes, HSP90B1 promoted OGD-induced pyroptosis and was associated with activation of NF-κB/NLRP3 signaling, whereas pharmacological inhibition of these pathways reduced pyroptosis-related responses. In a non-contact cardiomyocyte–macrophage co-culture system, cardiomyocyte HSP90B1 expression influenced the pro-inflammatory phenotype of macrophages. Our findings identify HSP90B1 as a key regulator of cardiomyocyte pyroptotic signaling and post-MI inflammatory remodeling, with cardiomyocyte HSP90B1 expression associated with M1-like macrophage polarization.
Hexokinase 2 (HK2), a key enzyme in the Warburg effect, is associated with poor prognosis in colorectal cancer (CRC). HK2 is known to exert glycolysis-independent functions, yet the underlying targets and mechanisms remain unclear. This study aims to investigate the functional role of ZNF366 as a direct target of HK2 in colorectal cancer and reveal a non-metabolic function of HK2 in CRC. HK2-binding proteins were identified by immunoprecipitation and mass spectrometry. ZNF366 expression was assessed by western blotting and qRT-PCR. Cell proliferation, invasion, and migration were evaluated by functional assays. In vivo tumor growth was examined using a xenograft model. Molecular mechanisms were dissected by co-immunoprecipitation and ubiquitination assays. ZNF366 is downregulated in CRC tissues and cells. Overexpression of ZNF366 suppresses cell proliferation, invasion, and migration in vitro, and inhibits tumor growth in vivo, accompanied by decreased levels of pERK1/2, Cyclin D1, and MMP9, whereas ZNF366 knockdown increases their expression, indicating a negative regulatory role of ZNF366 on malignant phenotypes. HK2 and ZNF366 protein levels are inversely correlated in CRC specimens. HK2 reduces ZNF366 protein levels without affecting its mRNA expression. Mechanistically, UBE3A is identified as the E3 ubiquitin ligase for ZNF366. HK2 enhances the interaction between ZNF366 and UBE3A, leading to increased polyubiquitylation and degradation of ZNF366, which in turn correlates with enhanced malignancy of CRC cells. Our findings suggest that HK2 facilitates UBE3A-dependent ZNF366 degradation, which may partially contribute to the tumor-promoting effect of HK2, revealing a novel HK2-UBE3A-ZNF366 regulatory axis that provides insights into the non-metabolic functions of HK2 in CRC.
