Circulating and tumor-infiltrating arginase 1-expressing cells in gastric adenocarcinoma patients were mainly immature and monocytic Myeloid-derived suppressor cells.

Myeloid-derived suppressor cells (MDSCs) are a group of heterogeneous cells derived from immature myeloid cells (IMCs). MDSCs are known to play important roles in tumor immune evasion. While we know that there are a large number of circulating and tumor-infiltrating MDSCs existing in gastric cancer (GC) patients, the phenotypic characteristics and arginase 1 (ARG1) expression levels of these MDSCs remain very unclear. In our study, flow cytometric analysis of circulating MDSCs from 20 gastric adenocarcinoma (GAC) patients found that ≥80% ARG1-expressing MDSCs were mainly early-stage MDSCs (HLA-DR-CD33+CD14-CD15-MDSCs). In addition, our investigation showed that tumor-infiltrating MDSCs from 6 GAC patients consisted of >35% ARG1-expressing naïve MDSCs (HLA-DR-CD33-CD11b-CD14-CD15-MDSCs), >15% early-stage MDSCs and >40% monocytic MDSCs (HLA-DR-CD14+MDSCs). This preliminary study describes the phenotypic characteristics and ARG1 expression levels of MDSCs from GAC patients and shows that circulating and tumor-infiltrating ARG1-expressing cells were mainly immature and monocytic MDSCs, which provides information to better understand the mechanisms that allow gastric cancer cells to evade the immune system.

Exosomal miRNA-107 induces myeloid-derived suppressor cell expansion in gastric cancer.

  Background: Myeloid-derived suppressor cells (MDSCs) promote immunosuppression in the tumor microenvironment, support tumor growth and survival, and may contribute to immunotherapy resistance. Recent studies showed that tumor-derived exosomes (TDEs) can induce MDSCs accumulation and expansion, the mechanisms of which are largely unknown. Methods: The morphologies and sizes of the exosomes was observed by using a JEM-1400 transmission electron microscope. MicroRNA(miR)-107 and ARG1, DICER1, PTEN, PI3K, AKT, mTOR, and NF-kB mRNAs were quantified by quantitative reverse tanscription PCR. Dual-Luciferase Reports Assay were used to examine the expression of genes which was targeted by miR-107. The expression of proteins were analyzed by using western blot. Results: MiR-107 was not only overexpressed in gastric cancer cells but also enriched in their secreted TDEs. Also, these miR-107 enriched TDEs could be taken up by HLA-DR-CD33+MDSCs, where miR-107 was able to target and suppress expression of DICER1 and PTEN genes. Dampened DICER1 expression supported expansion of MDSCs , while decreased PTEN led to activation of the PI3K pathway, resulting in increased ARG1 expression. Furthemore, gastric cancer-derived miR-107 TDEs, when dosed intravenously into mice, were also capable of inducing expansion of CD11b+Gr1+/high MDSCs in mouse peripheral blood and altering expression of DICER1, PTEN, ARG1, and NOS2 in the MDSCs. Conclusions: Our findings demonstrate for the first time that gastric cancer-secreted exosomes are able to deliver miR-107 to the host MDSCs where they induce their expansion and activition by targeting DICER1 and PTEN genes, thereby may provide novel cancer therapeutics target for gastric cancer.

Movement disorder in GNAO1 encephalopathy associated with gain-of-function mutations.

OBJECTIVE: To define molecular mechanisms underlying the clinical spectrum of epilepsy and movement disorder in individuals with de novo mutations in the GNAO1 gene. METHODS: We identified all GNAO1 mutations reported in individuals with epilepsy (early infantile epileptiform encephalopathy 17) or movement disorders through April 2016; 15 de novo mutant alleles from 25 individuals were introduced into the Gαo subunit by site-directed mutagenesis in a mammalian expression plasmid. We assessed protein expression and function in vitro in HEK-293T cells by Western blot and determined functional Gαo-dependent cyclic adenosine monophosphate (cAMP) inhibition with a coexpressed α2A adrenergic receptor. RESULTS: Of the 15 clinical GNAO1 mutations studied, 9 show reduced expression and loss of function (LOF; <90% maximal inhibition). Six other mutations show variable levels of expression but exhibit normal or even gain-of-function (GOF) behavior, as demonstrated by significantly lower EC50 values for α2A adrenergic receptor-mediated inhibition of cAMP. The GNAO1 LOF mutations are associated with epileptic encephalopathy while GOF mutants (such as G42R, G203R, and E246K) or normally functioning mutants (R209) were found in patients with movement disorders with or without seizures. CONCLUSIONS: Both LOF and GOF mutations in Gαo (encoded by GNAO1) are associated with neurologic pathophysiology. There appears to be a strong predictive correlation between the in vitro biochemical phenotype and the clinical pattern of epilepsy vs movement disorder.

[Analysis of association between the IRF5 gene single nucleotide polymorphism and allergic rhinitis].

OBJECTIVE: To study the possible association between interferon regulatory factor 5 (IRF5) gene polymorphism and allergic rhinitis (AR). METHODS: Six independent single nucleotide polymorphism (SNP, rs729302, rs4728142, rs3807306, rs2070197, rs11770589, rs2280714) were analyzed. The genotype and allele frequencies were detected in 110 AR patients and 101 healthy controls in Singapore Chinese population by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). RESULTS: Rs729302 was rejected as it was not polymorphic. For others SNP, no statistically significant difference was detected in genotype between AR and healthy control group (χ(2) value were 0.21, 5.02, 0.01, 2.91, 0.37, all P > 0.05). No statistically significant difference was detected in allele frequencies between AR and healthy control group (χ(2) value were 0.00, 2.78, 0.01, 2.31, 0.00, all P > 0.05). CONCLUSION: No association is observed between IRF5 and AR in Singapore Chinese population.

[To study of the nasal mucosa remodeling of allergic rhinitis patients].

OBJECTIVE: To explore whether there was tissue remodeling in the nasal mucosa of allergic rhinitis (AR) patients and detect the protein expressions of transforming growth factor beta1 (TGF-beta1), matrix metalloproteinases 9 (MMP-9) and tissue inhibitors of matrix metalloproteinases 1 (TIMP-1) in the nasal mucosa of these patients. METHOD: Pathologic staining was used to explore the mucosa of the middle turbinate tissues from 16 patients with mild AR, from 12 patients with severe AR, and from 15 non-AR, respect. The infiltrating of eosinophils and damage of epithelium were examined by the hematoxylin-eosin staining; goblet cells were counted by the alcian blue-periodic acid-schiff staining; the percentage area of extracellular matrix was determined by the MT; the protein expressions were measured by ELISA of TGF-beta1, MMP-9 and TIMP-1 in the middle turbinate tissues. RESULT: Compared with the control group, significant eosinophil infiltration and goblet cells were observed in both AR groups (P < 0.05). Evident epithelial damage and extracellular matrix deposition were observed in severe-AR group (P < 0.05). The expressions of TGF-beta1, MMP-9 and TIMP-1 in AR tissues were significant increased (P < 0.05). CONCLUSION: The nasal mucosa remodeling was observed in AR groups. The characteristics were as follows: eosinophils infiltration, epithelial damage, goblet cells hyperplasia and extracellular matrix deposition. TGF-beta1, MMP-9, TIMP-1 may play a role in the tissue remodeling processes.