Down-regulation of heparanase leads to the inhibition of invasion and proliferation of A549 cells in vitro and in vivo.

Heparanase is a mammalian endoglycosidase that degrades heparan sulfate at the cell surface and in the extracellular matrix. The expression of heparanase was detected in a wide variety of human malignant tumors and closely associated with tumor invasion, metastasis, and angiogenesis. However, the specific roles of heparanase and its mechanisms of regulating the malignant potential of non-small cell lung cancer (NSCLC) cells still remain unclear. In the present study, the expression of heparanase was down-regulated in NSCLC cell line by antisense oligodeoxynucleotide. Results showed that down-regulation of heparanase led to significant inhibition of invasive and proliferative potentials of A549 cells in vitro and in vivo. Further research demonstrated that down-regulation of heparanase significantly inhibited the angiogenic potential of A549 cells, which might be the mechanism responsible for the inhibition of A549 cell proliferation in BALB/c nude mice in vivo. These findings demonstrate that heparanase plays essential roles in regulating the invasion, proliferation, and angiogenesis of A549 cells.

Comprehensive Analysis of N6-Methyladenosine (m6A) RNA Methylation Regulators and Tumour Microenvironment Cell Infiltration Involving Prognosis and Immunotherapy in Gastroesophageal Adenocarcinomas.

Objective: Gastroesophageal adenocarcinoma (GEA) is a high deadly and heterogeneous cancer. RNA N6-methyladenosine (m6A) modification plays a non-negligible role in shaping individual tumour microenvironment (TME) characterizations. However, the landscape and relationship of m6A modification patterns and TME cell infiltration features remain unknown in GEA. Methods: In this study, we examined the TME of GEA using assessments of the RNA-sequencing data focusing on the distinct m6A modification patterns from the public databases. Intrinsic patterns of m6A modification were evaluated for associations with clinicopathological characteristics, underlying biological pathways, tumour immune cell infiltration, oncological outcomes, and treatment responses. The expression of key m6A regulators and module genes was validated by qRT-PCR analysis. Results: We identified two distinct m6A modification patterns of GEA (cluster 1/2 subgroup), and correlated two subgroups with TME cell-infiltrating characteristics. Cluster 2 subgroup correlates with a poorer prognosis, downregulated PD-1 expression, higher risk scores, and distinct immune cell infiltration. In addition, PPI and WGCNA network analysis were integrated to identify key module genes closely related to immune infiltration of GEA to find immunotherapy markers. COL4A1 and COL5A2 in the brown module were significantly correlated to the prognosis, PD-1/L1 and CTLA-4 expression of GEA patients. Finally, a prognostic risk score was constructed using m6A regulator-associated signatures that represented an independent prognosis factor for GEA. Interestingly, COL5A2 expression was linked to the response to anti-PD-1 immunotherapy, m6A regulator expression, and risk score. Conclusion: Our work identified m6A RNA methylation regulators as an important class of players in the malignant progression of GEA and were associated with the complexity of the TME. COL5A2 may be the potential biomarker which contributes to predicting the response to anti-PD-1 immunotherapy and patients' prognosis.

Upregulation of molecules associated with T-regulatory function by thymoglobulin pretreatment of human CD4+ cells.

BACKGROUND: This study evaluated the immunologic effects of thymoglobulin in modulating human CD4+ cells. METHODS: Human CD4+ cells were purified from peripheral blood mononuclear cells by negative selection method. CD4+ cells were pretreated with thymoglobulin and incubated for 72 hr. Cells and culture supernatants were collected and studied by real-time quantitative polymerase chain reaction, fluorescence activated cell scanning, multiplex cytokine assay, and mixed lymphocyte reaction (MLR). RESULTS: Thymoglobulin pretreated CD4+ cells demonstrated up-regulation of gene transcripts for CTLA-4, OX40, forkhead box P3 (Foxp3), CD25, IFN-gamma, IL-10, and IL-2 as determined by real-time quantitative polymerase chain reaction. Fluorescence-activated cell scanning analysis demonstrated that CD4+ cells, pretreated with thymoglobulin, up-regulated CD25 expression on their surface, and the surface expression of CTLA-4 and OX40 and the expression of intracellular Foxp3 were observed in these CD4+CD25+ cells. Additionally, MLR demonstrated that thymoglobulin-pretreated cells partially inhibited proliferation of untreated autologous CD4+ cells in response to allogeneic cells. The high levels of IFN-gamma, IL-10, IL-2, and IL-4 were detected by multiplex cytokine assay in supernatants collected from cultures of thymoglobulin-pretreated CD4+ cells. The lymphocyte proliferation of allogeneic MLR was also partially blocked in the presence of supernatants from cultures of thymoglobulin-pretreated CD4+ cells. CONCLUSIONS: This study demonstrates that the unique effects of thymoglobulin in modulating CD4+ cells may be an important mechanism for its action in inducing immunosuppression and transplant tolerance.