Objective To investigate the effect of resveratrol on the tumor microenvironment in osteosarcoma. Methods A C57BL/6 xenograft mouse model was established and treated with resveratrol. Single-cell sequencing was performed to analyze changes in the tumor microenvironment. Immunohistochemistry was used to assess immune cell infiltration, while Western blotting was conducted to examine alterations in cellular signaling pathways. Results Resveratrol significantly inhibited the proliferation of LM8 osteosarcoma cells in C57BL/6 mice compared to the control group. Additionally, CD8⁺ T cell recruitment was enhanced. The Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway was notably downregulated in LM8 osteosarcoma cells following resveratrol treatment. Conclusion Resveratrol promotes CD8⁺ T cell infiltration by inhibiting the JAK2/STAT3 signaling pathway, suggesting its potential as a therapeutic agent in osteosarcoma treatment.
Osteosarcoma/genetics* ; STAT3 Transcription Factor/genetics* ; Resveratrol/pharmacology* ; Animals ; Janus Kinase 2/genetics* ; Signal Transduction/drug effects* ; Tumor Microenvironment/immunology* ; Cell Line, Tumor ; Mice, Inbred C57BL ; Mice ; Humans ; Cell Proliferation/drug effects* ; Bone Neoplasms/metabolism* ; CD8-Positive T-Lymphocytes/drug effects* ; Xenograft Model Antitumor Assays

Objective To screen the potential key genes of osteosarcoma by bioinformatics methods and analyze their immune infiltration patterns. Methods The gene expression profiles GSE16088 and GSE12865 associated with osteosarcoma were obtained from the Gene Expression Omnibus(GEO),and the differentially expressed genes(DEGs)related to osteosarcoma were screened by bioinformatics tools.Gene Ontology(GO)annotation,Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment,and analysis of immune cell infiltration were then carried out for the DEGs.The potential Hub genes of osteosarcoma were identified by protein-protein interaction network,and the expression of Hub genes in osteosarcoma and normal tissue samples was verified via the Cancer Genome Atlas(TCGA). Results A total of 108 DEGs were screened out.GO annotation and KEGG pathway enrichment revealed that the DEGs were mainly involved in integrin binding,extracellular matrix (ECM) structural components,ECM receptor interactions,and phosphatidylinositol 3-kinase/protein kinase B(PI3K/Akt)signaling pathway.Macrophages were the predominant infiltrating immune cells in osteosarcoma.Secreted phosphoprotein 1(SPP1),matrix metallopeptidase 2(MMP2),lysyl oxidase(LOX),collagen type V alpha(II)chain(COL5A2),and melanoma cell adhesion molecule(MCAM)presented differential expression between osteosarcoma and normal tissue samples(all P<0.05). Conclusions SPP1,MMP2,LOX,COL5A2,and MCAM are all up-regulated in osteosarcoma,which may serve as potential biomarkers of osteosarcoma.Macrophages are the key infiltrating immune cells in osteosarcoma,which may provide new perspectives for the treatment of osteosarcoma.
Bone Neoplasms/immunology* ; Computational Biology/methods* ; Gene Expression Profiling/methods* ; Humans ; Osteosarcoma/immunology* ; Phosphatidylinositol 3-Kinases/genetics* ; Tumor-Associated Macrophages/immunology*

Bone Neoplasms ; immunology ; pathology ; Child ; Humans ; Osteosarcoma ; immunology ; pathology ; Rosette Formation

OBJECTIVETo investigate the cytotoxic effect of γδ T cells from osteosarcoma patients against interferon-γ (IFN-γ)-treated osteosarcoma cells in vitro.

METHODSHuman γδ T cells were amplified by zoledronate from peripheral blood cells of osteosarcoma patients. The expression of Fas on the osteosarcoma cells were measured by flow cytometry and quantitative real-time PCR analysis before and after IFN-γ treatment. The cytotoxicity of γδ T cells against osteosarcoma cells was evaluated with LDH assay.

RESULTSIFN-γ significantly enhanced the susceptibility of the osteosarcoma cell lines HOS and U2OS to the cytotoxicity of γDelta; T cells from osteosarcoma patients (P<0.01). IFN-γ obviously up-regulated the expression of Fas in HOS and U2OS cells (P<0.01). Anti-FasL mAb failed to inhibit the cytotoxicity of γδ T cells in untreated osteosarcoma targets (P>0.05), but significantly impaired γδ T cell cytotoxicity in IFN-γ pre-treated osteosarcoma targets (P<0.01).

CONCLUSIONIFN-γ can enhance the cytotoxic effect of human γδ T cells from osteosarcoma patients against osteosarcoma cells in vitro.

Bone Neoplasms ; metabolism ; Cell Line, Tumor ; Cytotoxicity, Immunologic ; Humans ; Interferon-gamma ; pharmacology ; Osteosarcoma ; immunology ; metabolism ; Receptors, Antigen, T-Cell, gamma-delta ; immunology ; T-Lymphocytes, Cytotoxic ; cytology ; drug effects ; immunology ; fas Receptor ; metabolism

OBJECTIVETo study the expression of membrane MICA (mMICA), soluble MICA (sMICA) and NKG2D receptor in cases of osteosarcoma and to analyze its clinical significance.

METHODSExpression of mMICA in osteosarcoma tissue of 43 cases was detected with immunohistochemistry. Expression of NKG2D in peripheral blood lymphocytes of 16 cases was analyzed by flow cytometry. Serum level of soluble MICA (sMICA) was measured by ELISA.

RESULTSmMICA was widely expressed in osteosarcoma tissue (37/43). Expression of NKG2D in peripheral blood lymphocytes was significantly decreased. High levels of mMICA and NKG2D expression were associated with better differentiation and earlier tumor stage of osteosarcoma (P < 0.05). A significant increase in serum level of sMICA was demonstrated in patients with metastasis and advanced tumor.

CONCLUSIONSThe mMICA expression in tumor tissue, NKG2D expression in peripheral lymphocytes and serum sMICA level correlate with the differentiation and stage of osteosarcoma. These parameters may thus represent potential diagnostic and prognostic markers in patients with osteosarcoma. Manipulation of the MICA-NKG2D pathway may become a target of immunotherapy for osteosarcoma.

Bone Neoplasms ; blood ; metabolism ; pathology ; Cell Differentiation ; Enzyme-Linked Immunosorbent Assay ; Flow Cytometry ; Histocompatibility Antigens Class I ; blood ; metabolism ; Humans ; Immunohistochemistry ; Lymphocytes ; immunology ; NK Cell Lectin-Like Receptor Subfamily K ; metabolism ; Neoplasm Staging ; Osteosarcoma ; blood ; metabolism ; pathology

OBJECTIVETo investigate the effect of anti-VEGF antibody on angiogenesis induced by osteosarcoma OS-732 cell line and tumor growth.

METHODSWith a tumor model on the chick embryo chorioallantoic membrane (CAM), the inhibition of angiogenesis and tumor growth by anti-VEGF antibody were observed under a stero-microscope and a light microscope. Furthermore, the proliferation and apoptosis in tumor cells and endothelial cells (EC) were studied by TdT-mediated duTP nick and labeling (TUNEL) and immunohistochemical staining using proliferating cell nuclear antigen (PCNA) monoclonal antibody.

RESULTSVEGF polyclonal antibody administration in tumor-bearing chick embryo resulted in growth arrest of xenografts and a markedly reduction in the new capillaries which converged upon the tumor. The tumor cell apoptotic index was higher in the anti-VEGF antibody treated group than the negative control group, but the proliferation index was not significantly different between them. At the same time, increased apoptosis and decreased proliferation in EC were also noted.

CONCLUSIONVEGF polyclonal antibody is able to inhibit the angiogenesis induced by OS-732 obviously, probably by the mechanism of inhibition of EC proliferation and promotion of their apoptosis, furtherly, which may contribute to the apoptosis of tumor cells and result in suppression of tumor growth.

Animals ; Antibodies ; therapeutic use ; Apoptosis ; Bone Neoplasms ; therapy ; Cell Division ; drug effects ; Chick Embryo ; Disease Models, Animal ; Endothelial Growth Factors ; immunology ; Endothelium, Vascular ; cytology ; drug effects ; Immunotherapy ; Lymphokines ; immunology ; Microscopy ; Neovascularization, Pathologic ; prevention & control ; Osteosarcoma ; therapy ; Vascular Endothelial Growth Factor A ; Vascular Endothelial Growth Factors