Hypoxia-induced Circular RNA hsa_circ_0006508 Promotes the Warburg Effect in Colorectal Cancer Cells

Background: The hypoxia-induced Warburg effect promotes colorectal cancer malignancy with altered circular RNA (circRNA) expression. Aims: To investigate the association with the Warburg effect in colorectal cancer and whether has_circ_0006508 can be induced by hypoxia. Study design: In vitro cell lines and human-sample study. Methods: The biological functions of circ_0006508 and miR-1272 in the viability, colony formation, and glycolysis under hypoxic conditions were determined by loss-of-function and gain-of-function experiments. The chromatin immunoprecipitation assay was used to demonstrate the direct binding between circ_0006508 promoters and hypoxia-inducible factor 1α (HIF-1α). Transcription activity was subjected to the Luciferase reporter assay. The correlation of circ_0006508 and miR-1272 with overall survival was determined with the Kaplan-Meier analysis. Results: Upregulated circ_0006508 and downregulated miR-1272 were observed in colorectal cancer samples, which was associated with the TNM stage and overall survival. Functional assays demonstrated that the hypoxia-induced upregulated circ_0006508 and downregulated miR-1272 promoted the viability and Warburg effect of colorectal cancer in vitro. Mechanistically, HIF-1α-induced circ_0006508 could directly sponge miR-1272, which played a suppressive role in glycolysis. Conclusion: Circ_0006508-mediated miR-1272 inhibition could promote the malignant behaviors of colorectal cancer with an upregulated Warburg effect.

Moscatilin suppresses the inflammation from macrophages and T cells.

In this study, we aim to investigate moscatilin in alleviating symptoms of autoimmune liver disease (ALD) in a concanavalin A (ConA)-induced liver injury mouse model and elucidate the underlying mechanisms. ALD mouse models were constructed by intravenous injection of ConA (20 mg/kg) and the serum level of alanine aminotransferase (ALT) was measured using an enzyme-linked immunosorbent assay. Moscatilin in various doses was administered for two days starting from a day before the ConA injection. We showed that moscatilin dose-dependently decreased ALT levels in liver tissue of ALD mouse models. Ifng and Tnfa also showed significant downregulation in liver tissues. Macrophages only showed significant Tnfa downregulation and CD4+ T cells only showed significant Ifng downregulation at high moscatilin doses. In vivo administration of moscatilin induced interleukin-37 upregulation in hepatic tissues. In vitro, moscatilin also induced IL-37 upregulation in hepatic stellate cell line JS-1 rather than immune cells represented by RAW264.7 and CTLL-2 cell lines, suggesting that the hepatic stellate cell is majorly responsive to moscatilin treatment in terms of interleukin (IL)-37 upregulation. Our data indicate that moscatilin could alleviate liver injury in ConA-induced ALD mouse models through anti-inflammatory activities, warranting further development of moscatilin as a new drug in treating ALD.

HMGB1/RAGE pro-inflammatory axis promotes vascular endothelial cell apoptosis in limb ischemia/reperfusion injury.

OBJECTIVE: High-Mobility Group Box 1 (HMGB1) promotes vascular injuries induced by limb Ischemia and Reperfusion (IR), but the molecular mechanisms are not well understood. This study aimed to investigate the role of Receptor for Advanced-Glycation End products (RAGE) in HMGB1-regulated inflammatory response and vascular injury in limb IR using the rat IR and cellular Hypoxia and Reoxygenation (HR) models. METHODS: We analyzed the vascular structure and elastic fiber deposition in rat femoral arteries by histological staining. We determined gene expression in vascular tissues and cells by quantitative RT-PCR, Western blotting and immunofluorescence; analyzed the protein levels in rat serum or cell supernatant by ELISA; and assessed protein interaction by co-immunoprecipitation. We used CCK-8 for analyzing cell viability, and assessed apoptosis by Hoechst staining and flow cytometry. RESULTS: RAGE inhibition by FPS-ZM1 significantly repressed rat vascular injury that was induced by limb IR treatment. HMGB1 and RAGE expression, P38, ERK1/2, P65 and IKBa phosphorylation, as well as HIF-1a, NLRP3, Caspase-1, TNF-a and IL-6 expression and P65 in nucleus, increased in femoral arteries of a rat IR model and HUVEC undergoing HR treatment, whereas all the factors except HMGB1 and RAGE were inhibited by FPS-ZM1 treatment. In addition, we found that HMGB1 binds with RAGE in HUVEC undergoing HR treatment, which was suppressed by FPS-ZM1. Finally, the apoptosis of HUVEC also increased by HR treatment, but repressed under FPS-ZM1 treatment. CONCLUSION: HMGB1 binds with RAGE to promote vascular inflammation and endothelial cell apoptosis, which mediates vascular injury during acute limb IR.

Mir-22-3p Enhances the Chemosensitivity of Gastrointestinal Stromal Tumor Cell Lines to Cisplatin through PTEN/PI3K/Akt Pathway.

Mir-22-3p is associated with many important biological processes, including neuroprotection, tumorigenesis, and various other tumor progressions. Our study aimed to investigate the roles of Mir-22-3p in chemosensitivity of gastrointestinal stromal tumor (GIST-T1) cells to cisplatin and explore its underlying mechanisms. Mir-22-3p high-expressing cell line was established by transfecting GIST-T1 cell line cells with Mir-22-3p mimic. After treatment with cisplatin (10 µM), Cell counting kits-8 (CCK-8) method was used to detect the cell viability. Flow cytometry was applied to measure the degree of cell apoptosis. Scratch wound healing test was used to detect the migration ability of cells. The protein and mRNA levels of the phosphatase and tensin homolog deleted on chromosome ten (PTEN)/phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) pathway-related factors were analyzed by Western blot and qRT-PCR. The mRNA level of Mir-22-3p was increased in transfected GIST-T1 cells compared with that in control cells. The survival rate and Bcl-2/Bax ratio of GIST-T1 cells treated with both Mir-22-3p analogue and cisplatin were significantly decreased, while the apoptosis rate and protein level of caspase-3 were significantly increased (p<0.05). In addition, the mRNA and protein levels of PTENwere significantly increased in cells treated with both Mir-22-3p analogue and cisplatin (p<0.05), while the expression levels of PI3K and Akt were significantly decreased (p<0.05). Mir-22-3p overexpression can increase the chemosensitivity of cisplatin in human gastrointestinal stromal tumor cells by PTEN/PI3K/Akt pathway.

NF-κB/miR-223-3p/ARID1A axis is involved in Helicobacter pylori CagA-induced gastric carcinogenesis and progression.

Infection with Helicobacter pylori (H. pylori) and the resulting gastric inflammation is regarded as the strongest risk factor for gastric carcinogenesis and progression. NF-κB plays an important role in linking H. pylori-mediated inflammation to cancer. However, the underlying mechanisms are poorly understood. In this study, we find that H. pylori infection induces miR-223-3p expression in H. pylori CagA-dependent manner. NF-κB stimulates miR-223-3p expression via directly binding to the promoter of miR-223-3p and is required for H. pylori CagA-mediated upregulation of miR-223-3p. miR-223-3p promotes the proliferation and migration of gastric cancer cells by directly targeting ARID1A and decreasing its expression. Furthermore, miR-223-3p/ARID1A axis is involved in CagA-induced cell proliferation and migration. In the clinical setting, the level of miR-223-3p is upregulated, while ARID1A is downregulated significantly in human gastric cancer tissues compared with the corresponding noncancerous tissues. The expression level of miR-223-3p is significantly higher in H. pylori-positive gastric cancer tissues than that in H. pylori-negative tissues. Moreover, a negative correlation between miR-223-3p and ARID1A expression is found in the gastric cancer tissues. Taken together, our findings suggested NF-κB/miR-223-3p/ARID1A axis may link the process of H. pylori-induced chronic inflammation to gastric cancer, thereby providing a new insight into the mechanism underlying H. pylori-associated gastric diseases.

Mutual information network-based support vector machine strategy identifies salivary biomarkers in gastric cancer.

PURPOSE: To determine the vital salivary transcriptomic biomarkers for the early detection of gastric cancer via comparing classification efficiency of multiple candidate genes. METHODS: We firstly identified 5 kinds of candidate genes related to gastric cancer, including differential pathway genes (DPGs) based on the attract method, hub genes in differential pathways based on mutual information network (MIN) analysis, differentially expressed genes (DEGs) identified by Significance Analysis of Microarrays (SAM), informative genes (DEGs in differential pathways), and key genes (hub DEGs). Then, the classification efficiency of these 5 kinds of candidate genes were assessed using support vector machines (SVM) model. The genes with the best classification efficiency were considered as salivary biomarkers in gastric cancer. RESULTS: Using the attract method, we screened 5 differential pathways in gastric cancer, in which there were 349 DPGs. Based on these DPGs, MIN with 345 genes and 1313 interactions was constructed, from which we obtained 26 hub genes by topological analysis. Meanwhile, we identified 374 DEGs in gastric cancer. Combining DEGs with DPGs and hub genes respectively, we selected 16 informative genes and 5 key genes. SVM analysis showed that the key genes presented the best classification efficiency with AUC=0.99, specificity=1.00, sensitivity=0.98 and MCC=0.95, which would be considered as salivary biomarkers in gastric cancer. CONCLUSIONS: This study successfully explored several salivary biomarkers for the non-invasive detection of gastric cancer with high specificity and sensitivity, which might contribute to the early detection and treatment of gastric cancer.