CircPRDM5 inhibits the proliferation, migration, invasion, and glucose metabolism of gastric cancer cells by reducing GCNT4 expression in a miR-485-3p-dependent manner.

Circular RNA (circRNA) plays a key part in the pathological process of gastric cancer (GC). The study is organized to analyze the function of circPRDM5 in GC cell tumor properties. Expression levels of circPRDM5, miR-485-3p, glucosaminyl (N-acetyl) transferase 4 (GCNT4), ki67, E-cadherin, N-cadherin, and hexokinase 2 (HK2) were analyzed by quantitative real-time polymerase chain reaction (PCR), Western blotting or immunohistochemistry assay. Cell proliferation was assessed by cell colony formation assay and 5-ethynyl-2'-deoxyuridine assay. Cell migration and invasion were investigated by transwell assay. Glycolysis was evaluated by the Seahorse XF Glycolysis Stress Test Kit. Dual-luciferase reporter assay and RNA pull-down assay were performed to identify the associations among circPRDM5, miR-485-3p, and GCNT4. Xenograft mouse model assay was conducted to determine the effects of circPRDM5 on tumor formation in vivo. CircPRDM5 and GCNT4 expression were downregulated, while miR-485-3p expression was upregulated in GC tissues and cells when compared with paracancerous tissues or human gastric epithelial cells. CircPRDM5 overexpression inhibited proliferation, migration, invasion, and glucose metabolism of GC cells; however, circPRDM5 depletion had the opposite effects. CircPRDM5 repressed tumor properties of GC cells in vivo. MiR-485-3p restoration relieved circPRDM5-induced effects in GC cells. GCNT4 overexpression remitted the promoting effects of miR-485-3p mimics on GC cell malignancy. CircPRDM5 acted as a sponge for miR-485-3p, and GCNT4 was identified as a target gene of miR-485-3p. Moreover, circPRDM5 regulated GCNT4 expression by interacting with miR-485-3p.CircPRDM5 acted as a miR-485-3p sponge to inhibit GC progression by increasing GCNT4 expression, proving a potential target for GC therapy.

Circ_0005758 impedes gastric cancer progression through miR-1229-3p/GCNT4 feedback loop.

Circular RNAs (circRNAs) have been reported to have roles in the carcinogenesis of gastric cancer (GC). Circ_0005758 was discovered to be decreased in GC, here, the detailed functions and molecular mechanism of circ_0005758 in GC progression were investigated. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were used to measure the levels of genes and proteins. The biological functions of circ_0005758 on GC progression were investigated by using in vitro assays, including 5-ethynyl-2'-deoxyuridine (EDU), transwell, tube formation and flow cytometry, and in vivo murine xenograft model. The binding between miR-1229-3p and circ_0005758 or GCNT4 (Glucosaminyl (N-Acetyl) Transferase 4) was confirmed using dual-luciferase reporter assay and pull-down assay. Circ_0005758 expression was decreased in GC tissues and cells, re-expression of circ_0005758 induced apoptosis and suppressed proliferation, migration, invasion and angiogenesis in GC cells in vitro, and impeded xenograft tumor growth in nude mice. Mechanistically, circ_0005758 sequestered miR-1229-3p to release GCNT4 expression, indicating the circ_0005758/miR-1229-3p/GCNT4 competing endogenous RNA (ceRNA) network GC cells. Besides, an increased miR-1229-3p level and a decreased GCNT4 expression were observed in GC. Rescue experiments demonstrated that miR-1229-3p up-regulation or GCNT4 down-regulation attenuated the anticancer effects of circ_0005758 re-expression on GC cells. Circ_0005758 acts as a tumor suppressor to impede gastric cancer progression via miR-1229-3p/GCNT4 axis, implying that therapeutic targeting of circ_0005758 may better to prevent gastric cancer.

Glycogene Expression Profile of Human Limbal Epithelial Cells with Distinct Clonogenic Potential.

Glycans function as valuable markers of stem cells but also regulate the ability of these cells to self-renew and differentiate. Approximately 2% of the human genome encodes for proteins that are involved in the biosynthesis and recognition of glycans. In the present study, we evaluated the expression of a small subset of glycogenes in human limbal epithelial cells with distinct clonogenic potential. Individual clones were classified as abortive or clonogenic, based on the fraction of the terminal colonies produced; clones leading exclusively to terminal colonies were referred to as abortive while those with half or fewer terminal colonies were referred to as clonogenic. An analysis of glycogene expression in clonogenic cultures revealed a high content of transcripts regulating the galactose and mannose metabolic pathways. Abortive clones were characterized by increased levels of GCNT4 and FUCA2, genes that are responsible for the branching of mucin-type O-glycans and the hydrolysis of fucose residues on N-glycans, respectively. The expansion of primary cultures of human limbal epithelial cells for 10 days resulted in stratification and a concomitant increase in MUC16, GCNT4 and FUCA2 expression. These data indicate that the clonogenic potential of human limbal epithelial cells is associated with specific glycosylation pathways. Mucin-type O-glycan branching and increased fucose metabolism are linked to limbal epithelial cell differentiation.

MicroRNA MiR-130a-3p promotes gastric cancer by targeting Glucosaminyl N-acetyl transferase 4 (GCNT4) to regulate the TGF-ß1/SMAD3 pathway.

Gastric cancer is the third-leading cause of cancer-related deaths worldwide. Dysregulation of glucosaminyl (N-acetyl) transferase 4 (GCNT4) gene and miR-130a-3p gene has been reported in the development of gastric cancer. We elucidated the function of the miR-130a-3p-GCNT4 axis in gastric cancer. Reverse transcription quantitative polymerase-chain reaction measured miR-130a-3p and GCNT4 levels in gastric cancer tissues and cells. The interaction between miR-130a-3p and GCNT4 was assessed using luciferase and RNA pull-down assays. Biological roles of miR-130a-3p and GCNT4 were determined using cell proliferation, migration, and invasion assays in gastric cancer cells. In addition, the effect of miR-130a-3p on the tumor growth in vivo was investigated using tumor xenografts assay. Levels of total TGF-ß1, phosphorylated SMAD3 (p-SMAD3), and SMAD3 were measured by using western blot. The results showed that miR-130a-3p levels were increased, while GCNT4 levels were reduced in gastric cancer tissues and cell lines. While miR-130a-3p mimics facilitated cellular proliferation, migration, and invasion in vitro, promoted tumor growth in vivo, and activated the TGF-ß1/SMAD3 signaling pathway, overexpression of GCNT4 prevented the growth of gastric cancer cells and restrained the activation of the TGF-ß1/SMAD3 pathway. Mechanistically, miR-130a-3p suppressed gastric cancer genesis by inhibiting GCNT4 expression and activating the TGF-ß1/SMAD3 signaling pathway. Altogether, we proposed that targeting of GCNT4 and activation of the TGF-ß1/SMAD3 signaling pathway by miR-130a-3p enhanced the growth of gastric cancer cells. This study provides important strategies for the selection of therapeutic targets for gastric cancer treatment involving miR-130a-3p/GCNT4/TGF-ß1/SMAD3 axis.

GCNT4 is Associated with Prognosis and Suppress Cell Proliferation in Gastric Cancer.

BACKGROUND: GCNT4 is a member of the glucosaminyl (N-acetyl) transferases family that has been implicated in multiple human malignancies. However, the role of GCNT4 in gastric cancer (GC) is unknown. In this present study, we aimed to explore the role and clinicopathological correlation of GCNT4 in GC. MATERIALS AND METHODS: We first evaluated the dysregulation of GCNT4 in The Cancer Genome Atlas (TCGA) and then we performed RT-qPCR and immunohistochemistry to validate the results in a cohort of in-house patients. The clinicopathological correlation and function of GCNT4 in GC were also analysed. RESULTS: GCNT4 was found to be significantly downregulated in GC. In addition, GCNT4 expression correlated with tumour depth, nervous invasion and pathological tumor-node-metastasis (pTNM) stage. Moreover, lower GCNT4 levels conferred poor overall survival (OS) and disease-free survival (DFS) to GC patients. Multivariate Cox regression analysis revealed that GCNT4 protein expression is an independent prognostic factor for OS in patients with GC. Further functional experimental results revealed that overexpression of GCNT4 appears to halt GC cell proliferation and the cell cycle. CONCLUSION: Altogether, these findings indicated that GCNT4 regulates the GC cell cycle and have important implications for the selection of therapeutic targets to prevent tumour proliferation.