南方医科大学学报杂志最新文献

Objectives: To investigate the association of NUF2 expression with tumor prognosis and its regulatory role in tumor microenvironment.

Methods: We analyzed NUF2 expression, its prognostic value, and is immune-related functions across different cancer types using datasets from the Human Protein Atlas (HPA), TCGA, GTEx, CCLE, and TIMER. RT-qPCR, Western blotting, and immunohistochemistry were used to detect NUF2 expression in liver cancer cell lines and tissue and blood samples from patients with liver cancer. GO, KEGG, and GSEA analyses were conducted to explore the molecular mechanisms of NUF2 and its related genes, and a competitive endogenous RNA (ceRNA) network for NUF2 in liver cancer was constructed.

Results: NUF2 expression was upregulated in the tumor tissues of 27 cancers and was associated with clinical stages in several cancers. High NUF2 expressions were correlated with poor overall survival, disease-specific survival, progression-free survival, and disease-free survival of cancer patients. NUF2 expression levels were positively correlated with tumor mutational burden, microsatellite instability, infiltrating immune cells, immune cell marker genes and immune checkpoint genes in different cancers. RT-qPCR, Western blotting, and immunohistochemistry confirmed that NUF2 expression was upregulated in liver cancer cell lines and tumor tissues and blood samples of liver cancer patients, and was decreased significantly after operation. GO, KEGG and GSEA analyses indicated that NUF2 was involved in chromosome segregation and cell cycle and was associated with glycine, serine and threonine metabolism.

Conclusions: NUF2 expression is upregulated in 27 cancers and is associated with clinical stage and poor prognosis in some malignancies. NUF2 expression is closely correlated with immune cell infiltration in different cancers, suggesting its potential value for predicting immunotherapy response in these cancers.

Objectives: To explore the mechanism by which histone deacetylase 1 (HDAC1) regulates steroid-induced apoptosis of mouse osteocyte-like MLO-Y4 cells.

Methods: MLY-O4 cells were treated with 400 nmol/L trichostatin A (TSA) or 1 mmol/L dexamethasone for 24 h or transfected with a HDAC1-overexpressing vector prior to TSA or dexamethasone treatment. The changes in the expressions of HDAC1, SP1, cleaved caspase-3 and Bax, SP1 acetylation level, cell proliferation, and cell apoptosis were examined. The interaction between HDAC1 and SP1 was determined with immunoprecipitation assay and Western blotting.

Results: Treatment with dexamethasone significantly increased cell apoptosis, enhanced the expressions of cleaved caspase-3 and Bax, reduced HDAC1 expression, and suppressed proliferation of MLO-Y4 cells. Both TSA and dexamethasone obviously increased SP1 acetylation level and the expression of SP1 in MLO-Y4 cells. HDAC1 overexpression in the cells significantly attenuated the effect of TSA and dexamethasone, promoted cell proliferation, lowered the expressions of SP1, cleaved caspase-3 and Bax, and inhibited dexamethasone-induced cell apoptosis. Immunoprecipitation assay and Western blotting demonstrated the interaction between HDAC1 and SP1 in the cells.

Conclusions: HDAC1 inhibits dexamethasone-induced apoptosis and promotes proliferation of cultured mouse osteocytes by suppressing SP1 expression via promoting its deacetylation.

Objectives: To investigate the effect of high glucose on macrophage polarization and the role of immune-responsive gene 1 (IRG1) in mediating its effect.

Methods: RAW264.7 cells were transfected with IRG1-overexpressing plasmid or IRG1 siRNA via electroporation and cultured in either normal or high glucose for 72 h to observe the changes in cell viability and morphology using CCK-8 assay and phase contrast microscopy. The protein levels of IRG1, iNOS, Arg-1, IL-1β and IL-10 in the treated cells were detected with Western blotting, and the fluorescence intensities of iNOS and Arg-1 were detected using immunofluorescence assay. The protein levels of IL-1β and IL-10 in the culture medium were determined with ELISA.

Results: High glucose exposure significantly reduced IRG1 and Arg-1 expressions, increased iNOS and IL-1β expressions and IL-1β secretion, and decreased IL-10 level in RAW264.7 cells. Transfection with the IRG1-overexpressing plasmid provided the cells with obvious resistance to high glucose-induced changes in iNOS, Arg-1, IL-1β and IL-10, whereas IRG1 knockdown further enhanced the effects of high glucose exposure on Arg-1 expression and the expression and secretion of IL-10.

Conclusions: High glucose promotes M1 polarization of the macrophages possibly through a mechanism to inhibit the expression of IRG1 protein, thus leading to chronic inflammatory response.

Objectives: To investigate the mechanism through which N-acetylneuraminic acid (Neu5Ac) exacerbates hypoxia/reoxygenation (H/R) injury in rat cardiomyocytes (H9C2 cells).

Methods: H9C2 cells were cultured in hypoxia and glucose deprivation for 8 h followed by reoxygenation for different durations to determine the optimal reoxygenation time. Under the optimal H/R protocol, the cells were treated with 0, 5, 10, 20, 30, 40, 50, and 60 mmol/L Neu5Ac during reoxygenation to explore the optimal drug concentration. The cells were then subjected to H/R injury followed by treatment with Neu5Ac, Fer-1 (a ferroptosis inhibitor), or both. The changes in SOD activity, intracellular Fe²⁺ and lipid ROS levels in the cells were evaluated, and the cellular expressions of Nrf2, GPX4, HO-1, FSP1, and xCT proteins were detected using Western blotting.

Results: Following hypoxia and glucose deprivation for 8 h, the cells with reoxygenation for 6 h, as compared with other time lengths of reoxygenation except for 9 h, showed the lowest expression levels of Nrf2, GPX4, HO-1, and FSP1 proteins (P<0.001). Neu5Ac treatment of dose-dependently decreased the viability of the cells with H/R injury with an IC₅₀ of 30.07 mmol/L. Reoxygenation for 3 h with normal glucose supplementation and a Neu5Ac concentration of 30 mmol/L were selected as the optimal conditions in the subsequent experiments. The results showed that Neu5Ac could significantly increase SOD activity, Fe²⁺ and lipid ROS levels and reduce Nrf2, GPX4, HO-1, and FSP1 protein expressions in H9C2 cells with H/R injury, but its effects were significantly attenuated by treatment with Fer-1.

Conclusions: Neu5Ac exacerbates ferroptosis of myocardial cells with H/R injury by inhibiting the Nrf2 axis to promote the production of ROS and lipid ROS.

Objectives: To investigate the inhibitory effect of Danshen Injection on endothelial-mesenchymal transition (EndMT) induced by peritoneal dialysis fluid in HMrSV5 cells and the role of the TGF‑β/Smad signaling pathway in mediating this effect.

Methods: HMrSV5 cells cultured in 40% peritoneal dialysis solution for 72 h to induce EndMT were treated with 0.05%, 0.1% and 0.5% Danshen Injection. CCK-8 assay was used to assess the changes in viability of the treated cells, and the levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), transforming growth factor-β (TGF-β), and vascular endothelial growth factor (VEGF) in the cell supernatant were detected using ELISA; Western blotting was performed to detect the protein expressions of E-cadherin, α-smooth muscle actin (α-SMA), p-Smad 2/3, and Smad 7 in the cells.

Results: Culture in 40% peritoneal dialysis fluid for 72 induced significant EndMT in HMrSV5 cells, which exhibited obviously lowered cell viability. Danshen Injection within the concentration range of 0.025%-1.5% did not significantly affect the viability of the cells. Exposure of HMrSV5 cells to peritoneal dialysis fluid for 72 h significantly increased the production of IL-6, TNF‑α, TGF‑β and VEGF, upregulated the protein expressions of α‑SMA and p-Smad 2/3, and lowered the expressions of E-cadherin and Smad7 proteins. Treatment of the exposed cells with Danshen injection significantly increased cell viability and cellular expressions of E-cadherin and Smad 7 proteins and reduced the production of IL-6, TNF-α, TGF-β and VEGF and the protein expressions of α‑SMA and p-Smad 2/3.

Conclusions: Danshen Injection can suppress peritoneal dialysis fluid-induced EndMT in HMrSV5 cells possibly by regulating the TGF-β/Smad signaling pathway.

Objectives: To observe the role of miR-139-5p and Notch1 signaling pathway in regulation of homing of bone mesenchymal stem cells (BMSCs) of asthmatic rats.

Methods: Normal rat BMSCs were co-cultured with bronchial epithelial cells from normal or asthmatic rats, followed by transfection with miR-139-5p mimics or a negative control sequence. The changes in cell viability and cell cycle were analyzed, and the cellular expressions of CXCR4 and SDF-1 were detected using immunofluorescence staining. The changes of BMSC homing after the transfection were observed, and the expressions of Notch1, RBP-J, and Hes1 mRNAs and proteins and Th1/Th2 cytokines were detected with RT-qPCR, Western blotting or ELISA.

Results: The co-cultures of BMSCs and asthmatic bronchial epithelial cells showed significantly decreased expressions of miR-139-5p, IL-2 and IL-12 and increased expressions of CXCR4, SDF-1, IL-5, IL-9, Notch1, RBP-J, and Hes1. Transfection with miR-139-5p mimics significantly increased the expressions of miR-139-5p, IL-2, CXCR4 and SDF-1 and lowered the expression levels of IL-5, IL-9, Notch1, activated Notch1, and Hes1 in the co-cultured cells. Correlation analysis showed that BMSC homing was positively correlated with miR-139-5p and IL-12 and negatively correlated with IL-5 expression. The expression of CXCR4 was negatively correlated with activated Notch1, and SDF-1 was positively correlated with miR-139-5p but negatively correlated with Notch1 expression.

Conclusions: High expression of miR-139-5p promotes homing of BMSCs in asthma by targeting the Notch1 signaling pathway to regulate the expressions of Th1/Th2 cytokines, thereby alleviating airway inflammation.

Objectives: To study the relationship between traditional Chinese cultural beliefs and suicide risk in Chinese medical postgraduate students.

Methods: The Chinese Traditional Cultural Belief Scale (CTCBS) and Suicidal Behavior Questionnaire (SBQ-R) were used to investigate 541 medical postgraduate students in a medical university.

Results: The total score of traditional Chinese cultural belief of the medical postgraduate students was 49.68±6.85, and 66.9% of them had a clear cultural belief. The detection rate of suicide risk among the medical postgraduates was 15.7%, and 20.1% of them reported suicidal ideation within the past year. Traditional Chinese cultural belief was negatively correlated with suicide risk among the medical postgraduates (r=-0.210, P<0.001), and those with higher levels of cultural belief had lower SBQ-R scores (F=6.255, P<0.01). The medical postgraduates with lower cultural beliefs had a higher detection rate of suicide risk (28.6% vs 21.2% vs 12.7%). The students with high suicide risks had significantly lower total scores and all the dimension scores of CTCBS (P<0.001).

Conclusions: Most medical postgraduates have clear traditional Chinese cultural beliefs, which can be beneficial to reduce suicide risk among the students.

Objectives: To investigate the inhibitory effect of GSK484, a PAD4 inhibitor, on H3Cit expression following sepsis and its effects for improving sepsis-induced endothelial dysfunction.

Methods: Eighteen C57BL/6 mice were randomized into sham-operated group, sepsis model group and GSK484 treatment group (n=6), and in the latter two groups, models of sepsis were established by cecal ligation and puncture (CLP). The mice in GSK484 treatment group were given an intraperitoneal injection of GSK484 (4 mg/kg) on the second day following the surgery. Twenty-four hours after the injection, the mice were euthanized for measurement of serum levels of VEGF, ESM-1, IL-6 and IL-1β using ELISA. Lung tissue pathology was observed with HE staining, and pulmonary expressions of F-actin, VE-cadherin, ZO-1 and H3Cit proteins were detected using immunofluorescence staining and Western blotting. In primary cultured of mouse lung microvascular endothelial cells, the effect of stimulation with LPS (10 μg/mL) for 24 h on tube formation, proliferation, apoptosis and expressions of VEGF, ESM-1, IL-6 and IL-1β were assessed using CCK-8 assay, flow cytometry and ELISA.

Results: Compared to the sham-operated mice, the septic mice exhibited significant lung tissue pathologies characterized by vascular congestion, alveolar rupture, edema, and neutrophil infiltration. Serum levels of IL-6, IL-1β, VEGF, and ESM-1 were elevated, pulmonary expressions of F-actin, VE-cadherin, and ZO-1 were decreased, and H3Cit expression was increased significantly in the septic mice. GSK484 treatment effectively mitigated these changes in the septic mice. The LPS-stimulated endothelial cells showed increased productions of IL-6, IL-1β, VEGF and ESM-1, which were significantly reduced after treatment with 2.5 μmol/L GSK484.

Conclusions: GSK484 treatment effectively suppresses H3Cit expression in septic mice to ameliorate sepsis-induced endothelial dysfunction.

Objectives: To investigate the mechanism of PHPS1 for promoting apoptosis of oral squamous cell carcinoma cells and the role of AMPK in regulating tumor angiogenesis under hypoxic conditions.

Methods: Human oral squamous cell carcinoma Ca9-22 cells cultured in hypoxic conditions (1% O₂) were inoculated subcutaneously in 16 nude mice, which were divided into control group and PHPS1 group (n=8) for treatment with 10% DMSO and 10% PHPS1 respectively. Tumor growth in the mice was monitored till 14 days after the treatment, and the xenografts were examined pathologically using HE staining. In Ca9-22 cells cultured in 1% O₂, the effect of PHPS1, compound C (an AMPK inhibitor), and their combination on expressions of SHP-2, AMPK, HIF-1α, PD-L1, caspase-8, caspase-3 and BAX were evaluated using Western blotting.

Results: In the tumor-bearing nude mice, PHPS1 treatment significantly inhibited tumor growth and neovascularization. HE staining showed significantly reduced tumor angiogenesis in PHPS1-treated mice. In Ca9-22 cells in hypoxic cultures, PHPS1 treatment significantly decreased the expression levels of SHP-2, HIF-1α, PD-L1, ERK2, STAT3 and VEGF and increased the expression of AMPK. The inhibitory effects of PHPS1 on HIF-1α and PD-L1 were obviously attenuated by the addition of compound C. PHPS1 also enhanced the expressions of caspase-3, caspase-8 and Bax proteins and increased the phosphorylation levels of PD-L1 and S195 in Ca9-22 cells, and these effects were effectively attenuated by compound C.

Conclusions: PHPS1 can enhance PD-L1 serine phosphorylation by regulating SHP-2/AMPK activity to promote apoptosis of oral squamous cell carcinoma cells under hypoxic conditions.

Objectives: To investigate the synergistic inhibitory effects of AKBA and doxorubicin on malignant phenotype of triple-negative breast cancer (TNBC) MDA-MB-231 cells.

Methods: CCK-8 assay was used to determine the 48-h IC₅₀ of AKBA and doxorubicin in MDA-MB-231 cells, and SynergyFinder was employed to calculate the synergistic index and the optimal concentrations of the two agents. MDA-MB-231 cells treated with AKBA (22.5 μmol/L), doxorubicin (0.84 μmol/L) or their combination were examined for changes in cell proliferation, migration, invasion and apoptosis using Transwell migration, scratch assay, clone generation, RT-qPCR and Western blotting. Network pharmacology analysis was conducted to identify the downstream targets of AKBA in TNBC. In nude mouse models bearing subcutaneous MDA-MB-231 cell xenografts, the effects of normal saline, AKBA (50 mg/kg), doxorubicin (2.5 mg/kg), and AKBA combined with doxorubicin on xenograft growth and histopathology were observed.

Results: The IC₅₀ of AKBA and doxorubicin in MDA-MB-231 cells at 48 h was 45.15±0.97 μmol/L and 0.42±0.99 μmol/L, respectively. SynergyFinder confirmed the synergistic effect of AKBA and ADR with a ZIP>10. The combined treatment with AKBA and doxorubicin significantly inhibited the proliferation, migration and invasion, promoted apoptosis of MDA-MB-231 cells, and effectively suppressed xenograft growth in nude mice. Network pharmacology analysis predicted that AKBA affects the progression of TNBC through its downstream target AKBA.

Conclusions: AKBA combined with doxorubicin inhibits proliferation, migration and invasion, promotes apoptosis of MDA-MB-231 cells and suppresses MDA-MB-231 cell xenograft growth in nude mice. The combined use of AKBA can attenuate the toxic effects of doxorubicin in nude mice.