Glioma is the most common primary intracranial tumor. At present, the conventional treatment methods have limited effect and cannot significantly prolong the survival time of patients. Chemokine CCL2 is the most important member of the CC chemokine family, which can regulate glioma angiogenesis, immunosuppression, progression and invasion, and resistance to apoptosis. This article reviews the potential mechanism of CCL2 promoting the malignant progression of glioma, in order to provide new ideas and methods for the targeted therapy of glioma.

Objective:To explore the prognostic biomarkers of glioblastoma (GBM) in the tumor microenvironment (TME) and its function.Methods:A total of 169 GBM samples of 161 GBM patients were collected from the Cancer Genome Atlas (TCGA) database. ESTIMATE algorithm in R4.1.0 software was used to calculate the proportion of immune components and stromal components in TME, which were expressed as immune score and stromal score, respectively. According to the median value of the two scores, 169 GBM samples were divided into the high score group and the low score group, respectively, 84 each in each group (those whose scores were equal to the median were not involved in the grouping). The differentially expressed genes (DEG) [false discovery rate (FDR) < 0.05] between the high score group and the low score group of the two scores were obtained by using limma package, and the co-up-regulated and co-down-regulated DEG of the two scores were obtained by using Venn program. Based on the STRING database, the protein interaction (PPI) network of co-up-regulated and down-regulated DEG of immune score and stromal score was constructed, and the top 30 genes with connectivity were selected. Univariate Cox proportional hazard model analysis of overall survival (OS) of 161 GBM patients in the TCGA database was performed on co-up-regulated and down-regulated DEG between immune score and stromal score by using R4.1.0 software to obtain the DEG affecting OS. The intersection of the DEG obtained from PPI analysis and Cox analysis was taken as the prognostic core genes. According to the median expression value of prognostic core genes in GBM samples from the TCGA database, 161 patients were divided into prognostic core genes high expression group and low expression group (patients whose scores were equal to the median were not involved in the grouping), with 80 cases in each group. Kaplan-Meier survival analysis of OS was performed by using R4.1.0 software. GSEA 4.2.1 software was used to perform gene set enrichment analysis (GSEA) on all genes with transcriptome data of GBM patients in the two groups of the TCGA databases, and the main enriched functions of the two groups of genes were obtained. The CIBERSORT algorithm was used to test the accuracy of the proportion of tumor infiltrating immune cell (TIC) subsets in 169 GBM samples from the TCGA database, and 57 GBM samples were finally obtained. Immune cells with differential expression levels and immune cells related to the expression of prognostic core genes among the samples with different expression levels of prognostic core genes were analyzed; Venn program was used to obtain the intersection of immune cells with differential levels and related immune cells, and differentially expressed TIC related to expressions of prognostic core genes in GBM were obtained.Results:Based on the immune score and stromal score of GBM samples in the TCGA database, a total of 693 co-up-regulated and co-down-regulated DEG of both scores were screened out. After the intersection of 78 DEG related to OS obtained by univariate Cox regression analysis and 30 DEG obtained by PPI network results, CC motif chemokine receptor 2 (CCR2) was identified as the prognostic core gene ( HR = 1.294, 95% CI 1.060-1.579, P = 0.011). GBM patients with CCR2 high expression had worse OS compared with those with CCR2 low expression ( P = 0.009). GSEA analysis showed that genes in the CCR2 high expression group were mainly enriched in immune-related pathways, while genes in the CCR2 low expression group were mainly enriched in metabolism-related pathways. Among 57 screened GBM samples, there were differences in the levels of 3 immune cells between the CCR2 high expression group and the CCR2 low expression group ( P < 0.05). CCR2 expression was correlated with the levels of 9 immune cells (all P < 0.05). Venn program analysis showed that differentially expressed 3 TIC in GBM related to CCR2 gene expression were obtained; among them, M2 macrophages were positively correlated with CCR2 expression, while T follicular helper cell and activated NK cells were negatively correlated with CCR2 expression. Conclusions:CCR2 may be the core gene related to the prognosis in the TME of GBM. As reference, the level of CCR2 can help to predict the status of TME and prognosis in GBM patients, which is expected to provide a new direction for the treatment of GBM.

Objective: To investigate the role of microRNA-96-5p in the proliferation and invasion of gastric cancer cells and its molecular mechanism. Methods: From June 2015 to January 2017, 53 resected specimens were collected. The transcriptional levels of microRNA-96-5p and forkhead box Q1 (FoxQ1) in gastric cancer tissues and the matched para-cancerous tissues were quantified by quantitative real-time PCR (qRT-PCR). The expression of FoxQ1 protein was also detected by immunohistochemistry (IHC). The relationship between microRNA-96-5p expression and the clinicopathological features of gastric cancer and its correlation with FoxQ1 expression were analyzed. The expressions of miRNA-96-5p in gastric cancer tissue and adjacent normal tissue were detected by qRT-PCR. miRNA-96-5p mimics was transfected to BGC-823 gastric cancer cells. The effects of miRNA-96-5p on cell proliferation and invasion were detected by cell counting kit-8 (CCK-8) assay and Transwell assay, respectively. The protein expressions of FoxQ1, E-cadherin and vimentin were determined by western blot. The relationship between FoxQ1 and miRNA-96-5p expressed in BGC-823 cells was detected by dual-luciferase reporter assay. Results: The median expression of miRNA-96-5p in gastric cancer tissue was 1.05, significantly lower than 3.23 of para-cancerous tissues (P<0.05). The positive rate of FoxQ1 expression in gastric cancer tissue was 71.7%, significantly higher than 28.3% of para-cancerous tissues (P<0.05). The expression of FoxQ1 was negatively corelated with the level of miRNA-96-5p (r=-0.613, P=0.006). The expression of miRNA-96-5p in gastric cancer cell BGC-823 was significantly decreased compared with normal gastric epithelial cell (0.96±0.08 vs 2.84±0.15, P<0.05). The results of CCK-8 assay and Transwell assay showed that overexpression of miRNA-96-5p significantly reduced the proliferation and invasion abilities of gastric cancer cells (P<0.05). Overexpression of miRNA-96-5p decreased the protein level of FoxQ1. Moreover, it upregulated the expression of E-cadherin and downregulated the expression of vimentin. The result of dual-luciferase-3′-UTR reporter assay confirmed that miRNA-96-5p binds to the 3′UTR of FoxQ1. Conclusion miRNA-96-5p may suppress the proliferation, migration and epithelial-mesenchymal transition (EMT) of gastric cancer cell by down-regulation of FoxQ1.