Circular RNA (circRNA) is an intriguing class of RNA with covalently closed-loop structure and is highly stable and conservative. As new members of the ncRNAs, the function, mechanism, potential diagnostic biomarker, and therapeutic target have raised increased attention. Most circRNAs are presented with characteristics of abundance, stability, conservatism, and often exhibiting tissue/developmental-stage-specific manner. Over 30,000 circRNAs have been identified with their unique structures to maintain stability more easily than linear RNAs. An increased numbers of circRNAs are dysregulated and involved in several biological processes of malignance, such as tumorigenesis, growth, invasion, metastasis, apoptosis, and vascularization. Emerging evidence suggests that circRNAs play important roles by acting as miRNA sponge or protein scaffolding, autophagy regulators, and interacting with RNA-binding protein (RBP), which may potentially serve as a novel promising biomarker for prevention, diagnosis and therapeutic target for treatment of human cancer with great significance either in scientific research or clinic arena. This review introduces concept, major features of circRNAs, and mainly describes the major biological functions and clinical relevance of circRNAs, as well as expressions and regulatory mechanisms in various types of human cancer, including pathogenesis, mode of action, potential target, signaling regulatory pathways, drug resistance, and therapeutic biomarkers. All of which provide evidence for the potential utilities of circRNAs in the diagnosis and treatment of cancer. © 2020 Tang and Hann.Background Statins, which are used to lower blood cholesterol levels by inhibiting HMG-CoA reductase, have shown anticancer effects in many cancer cells. However, the role of statins in gastric cancer remains unclear. This study aims to investigate whether the statins could antagonize progression of gastric cancer cells and tried to find the molecule mechanism. Methods Effects of simvastatin on the morphology, proliferation, migration, apoptosis, and invasion of gastric cancer cells were detected and compared. Western blotting, cell viability assay, fluorescence, and transfection were employed to study the molecule mechanism of the effects and the interaction between YAP and β-catenin signaling. Results Simvastatin could inhibit proliferation, migration and invasion, and promote the apoptosis in gastric cancer cells. Mechanistic studies showed that simvastatin treatment could inhibit the expression of β-catenin and the activity of YAP and the downstream targets of YAP and β-catenin in gastric cancer cells. Moreover, we found that YAP and β-catenin could form a positive feedback loop in gastric cancer cells. Further investigation revealed that simvastatin mainly acted through by inhibiting the activity of RhoA to inhibit YAP and β-catenin, and the geranylgeranyl pyrophosphate pathway mediated this regulation. Conclusion Statins represent a promising therapeutic option for gastric cancer by simultaneously targeting YAP and β-catenin signaling. © 2020 Liu et al.Introduction Epithelial membrane protein 1 (EMP1), a member of the EMP family, is overexpressed in a large number of tumors and is thought to be a cellular connexin on the cell membrane and is involved in proliferation, invasion, metastasis of tumor cells, and epithelial-mesenchymal transition (EMT). Nevertheless, its biomedical function in ovarian cancer is still unclear. Methods EMP1 was detected in ovarian cancer cell lines by whole transcriptome resequencing. The mRNA of EMP1 was examined by qRT-PCR. The relationship between expression of EMP1 and clinical classification, metastasis, and shortened survival time in ovarian cancer specimens was analysed by immunohistochemical (IHC). The mechanism of EMP1 enhanced proliferation and invasion of ovarian cancer cells was determined by siRNA interference, colony formation, migration and invasion experiments, and Western blot. Results EMP1 was up-regulated in ovarian cancer cell lines and ovarian cancer tissues in comparison with non-cancerous ovarian specimens. High expression of EMP1 in ovarian cancer specimens was obviously related to high clinical classification, metastasis, and shortened survival time. High expressed EMP1 facilitates cell proliferation, invasion and EMT in ovarian cancer cells. Over-expressed EMP1 increased the protein levels of RAS/RAF/MAPK/c-JUN. Conclusion Over-expressed EMP1 in ovarian cancer promotes tumor cell proliferation, invasion, and EMT by the MAPK signaling pathway. © 2020 Liu et al.Introduction Ring finger protein 6 (RNF6) locates on the chromatin 13q.12.13, where amplification is frequently occurred in colorectal cancer (CRC). Previous studies have reported the role of RNF6 to accelerate the progression and metastasis of CRC. Methods In this paper, we mainly analyzed the potential of RNF6 to predict the prognosis and metastasis of CRC. Based on the cut-off value of RNF6, enrolled CRC patients were assigned into high- and low-level group. Correlation between RNF6 level and survival of CRC patients was assessed. Results Our findings revealed that RNF6 was upregulated in CRC tissues. IHC staining demonstrated higher positive expression of RNF6 in CRC tissues. Nearly 61.2% CRC patients had a positive expression of RNF6. Moreover, RNF6 was closely linked to lymphovascular invasion (LV) (P=0.006), invasion depth (P=0.001), metastasis (P less then 0.001) and TNM staging (P less then 0.001). In CRC tissues, RNF6 level was negatively correlated to that of E-cadherin (r=-0.7093, P less then 0.0001). OS (overall survival) and RFS (recurrence-free survival) were worse in CRC patients with high-level RNF6, and tumor cell metastasis was believed to be the major reason. Conclusion Therefore, RNF6 was confirmed to be a hallmark predicting the prognosis and metastasis in CRC patients. find more © 2020 Zhu and Wang.Purpose Hepatocellular carcinoma (HCC) has a high incidence in China and exploring effective ways for early diagnosis is an important method to improve the prognosis of patients with HCC. Additional studies reported that. Some kinds of microRNA (miRNA) in plasma will change accordingly during HCC progress, and this change can be used to diagnose HCC, especially with miRNA-122, miRNA-21 and miRNA-96. We were aiming at investigating the values of the exosomal miRNAs in diagnosis and prognosis for HCC patients. Patients and Methods Blood samples from 50 patients with HCC and 50 patients with hepatic cirrhosis and 50 healthy volunteers were obtained. The diagnostic accuracy of the plasma and exosomal miRNAs and the comparisons among different groups were measured by the area under the curve (AUC) on receiver operating characteristic (ROC) curve analysis. Results Expression levels of miRNA-21 and miRNA-96 were significantly higher in patients with HCC and of miRNA-122 were significantly lower in HCC compared with cirrhotic patients in both exosomes and plasma.find more