CircRNAs and miRNAs are involved in the progression of tumor. CircMCTP2 is considered as a novel tumor promoter. However, the exact functions of circMCTP2 in bladder cancer are still unclear. This study was designed to explore the underlying mechanisms of circMCTP2-modulated tumor development in bladder cancer.

The present study is an original research. The levels of circMCTP2 in a total of 39 bladder cancer specimens and cell lines were determined by RT-qPCR. The expression of FZD8 in T24 and RT-4 cells treated with miR-99a-5p mimics were examined using western blotting. In addition, the proliferative, migrative and invasive abilities of transfected cells were determined by CCK8 and Transwell assays. Furthermore, the apoptosis of transfected cells was evaluated using flow cytometry. Dual luciferase reporter assay was performed to elucidate the relationship between miR-99a-5p and circMCTP2/FZD8.

The levels of circMCTP2 were elevated in bladder cancer samples and cells, and this was related to worse survival rate. Downregulation of circMCTP2 suppressed growth and metastasis of cells, whereas the apoptotic rate of cells was enhanced. The levels of miR-99a-5rp was elevated after the downregulation of circMCTP2. Moreover, reverse correlation between the expression of miR-99a-5p and circMCTP2 was revealed in bladder cancer specimens. Additionally, FZD8 was the putative target of miR-99a-5p and the mimics of miR-99a-5p inhibited the proliferation, migration and invasion of bladder cancer cells via the FZD8/Wnt-b-catenin axis. Moreover, circMCTP2 regulated the growth and metastasis of bladder cancer cells potentially through regulating the miR-99a-5p/FZD8/Wnt-b-catenin axis. In summary, circMCTP2 was considered as an oncogenic factor through regulating the miR-99a-5p/FZD8/Wnt-b-catenin axis.

This novel signaling could regulate the biological behaviours of bladder cancer cells, and these findings highlighted circMCTP2 as a critical target for treating bladder cancer.

The clinical significance of hsa_circ_0004018 and hsa_circ_0003570 in patients with hepatitis B virus-related hepatocellular carcinoma (HBV-HCC) is unclear. We aimed to explore the clinical significance and prognostic utility of these two circular RNAs (circRNAs) in patients with HBV-HCC. Based on 86 paired tissue samples of HCC and adjacent non-HCC, the relative expression profiles of hsa_circ_0004018 and hsa_circ_0003570 were determined using quantitative real-time polymerase chain reactions. The cut-off values were the median expression of each of the two circRNAs in 86 patients with HBV-HCC. The combination group comprised patients with high levels of the two circRNAs. Clinicopathological features, body composition profiles at the L3 level, and survival rates were investigated. The expression of hsa_circ_0004018 and hsa_circ_0003570 was downregulated in HCC tissues compared with non-HCC tissues. High expression levels of hsa_circ_0003570 (hazard ratio (HR), 0.437; p = 0.009) and hsa_circ_0004018 (HR, 0.435; p = 0.005) were inversely independent risk factors for overall and progression-free survival in patients with HBV-HCC, whereas the combination group was also an inversely independent risk factor for overall (HR, 0.399; p = 0.005) and progression-free survival (HR, 0.422; p = 0.003) in patients with HBV-HCC. The combination of hsa_circ_0003570 and hsa_circ_0004018 may be a potential prognostic biomarker for HBV-HCC.

Circular RNAs (circRNAs) are class of non-coding RNA, which are characterized by a covalently closed loop structure. Functionally they can act on cellular physiology, notably by sponging microRNAs (miR), regulating gene expression or interacting with binding protein. To date, circRNAs might represent an interesting, underexploited avenue for new target discovery for therapeutic applications, especially in the liver. The first characteristic of non-alcoholic fatty liver disease (NAFLD) is hepatic cholesterol accumulation, followed by its advanced form of the affection, nonalcoholic steatohepatitis (NASH), due to the occurrence of lobular inflammation, irreversible fibrosis, and in some cases hepatocellular carcinoma (HCC). Therefore, studies have investigated the importance of the dysregulation of circRNAs in the onset of metabolic disorders. In this review, we summarize the potential role of circRNAs in the development of metabolic diseases associated with the liver such as NAFLD or NASH, and their potential to become therapeutic strategies for these pathologies.

Circular RNAs (circRNAs) are potential biomarkers owing to their stability, tissue specificity, and abundance. This study aimed to evaluate the clinical significance of hsa_circ_0003570 expression and to investigate its potential as a biomarker in hepatocellular carcinoma (HCC). We evaluated hsa_circ_0003570 expression in 121 HCC tissue samples, its association with clinicopathological characteristics, and overall and progression-free survival. Hsa_circ_0003570 expression was downregulated in HCC tissues. Low hsa_circ_0003570 expression was more common in tumors larger than 5 cm (odds ratio (OR), 6.369; 95% confidence interval (CI), 2.725−14.706; p < 0.001), vessel invasion (OR, 5.128; 95% CI, 2.288−11.494; p < 0.001); advanced tumor-node metastasis stage (III/IV; OR, 4.082; 95% CI, 1.866−8.929; p < 0.001); higher Barcelona Clinic Liver Cancer stage (B/C; OR, 3.215; 95% CI, 1.475−6.993; p = 0.003); and higher AFP (>200 ng/mL; OR, 2.475; 95% CI, 1.159−5.291; p = 0.018). High hsa_circ_0003570 expression was an independent prognostic factor for overall survival (hazard ratio (HR), 0.541; 95% confidence interval (CI), 0.327−0.894; p = 0.017) and progression-free survival (HR, 0.633; 95% CI, 0.402−0.997; p = 0.048). Hsa_circ_0003570 is a potential prognostic biomarker in patients with HCC, and further validation of hsa_circ_0003570 is needed.