Circ0120816 acts as an oncogene of esophageal squamous cell carcinoma by inhibiting miR-1305 and releasing TXNRD1

Abstract

Background Circular RNAs (circRNAs) have been discovered to participate in the carcinogenesis of multiple cancers. However, the role of circRNAs in esophageal squamous cell carcinoma (ESCC) progression is yet to be properly understood. This research aimed to investigate and understand the mechanism used by circRNAs to regulate ESCC progression. Methods Bioinformatics analysis was first performed to screen dysregulated circRNAs and differentially expressed genes in ESCC. The ESCC tissue samples and adjacent normal tissue samples utilized in this study were obtained from 36 ESCC patients. All the samples were subjected to qRT-PCR analysis to identify the expression of TXNRD1, circRNAs, and miR-1305. Luciferase reporter assay, RNA immunoprecipitation assay and RNA pull-down assay were later conducted to verify the existing relationship among circ0120816, miR-1305 and TXNRD1. CCK-8, BrdU, cell adhesion, cell cycle, western blot and caspase 3 activity assays were also employed to evaluate the regulation of these three biological molecules in ESCC carcinogenesis. To evaluate the effect of circ0120816 on ESCC tumor growth and metastasis, the xenograft mice model was constructed. Results Experimental investigations revealed that circ0120816 was the highest upregulated circRNA in ESCC tissues and that this non-coding RNA acted as a miR-1305 sponge in enhancing cell viability, cell proliferation, and cell adhesion as well as repressing cell apoptosis in ESCC cell lines. Moreover, miR-1305 was observed to exert a tumor-suppressive effect in ESCC cells by directly targeting and repressing TXNRD1. It was also noticed that TXNRD1 could regulate cyclin, cell adhesion molecule, and apoptosis-related proteins. Furthermore, silencing circ0120816 was found to repress ESCC tumor growth and metastasis in vivo. Conclusions This research confirmed that circ0120816 played an active role in promoting ESCC development by targeting miR-1305 and upregulating oncogene TXNRD1.

Hsa_circ_0072008 regulates cell proliferation, migration, and invasion in cervical squamous cell carcinoma via miR-1305/helicase, lymphoid specific (HELLS) axis

“…For example, miR-1305 is related to cell metastasis in bladder cancer [ 10 ]. Besides, miR-1305 takes part in regulating cell adhesion and cell apoptosis in esophageal squamous cell carcinoma cells [ 11 ]. Moreover, miR-1305 acts as a vital regulator in hepatocellular carcinoma [ 12 ].…”

Exosomal circRNA FNDC3B promotes the progression of esophageal squamous cell carcinoma by sponging miR-490-5p and regulating thioredoxin reductase 1 expression

“…Importantly, Li et al . disclosed that TXNRD1 was overexpressed in ESCC tissues, and miR-1305 exerted a tumor-suppressive function in ESCC cells via repressing TXNRD1 [ 23 ]. Consistently, we found that TXNRD1 level was enhanced in ESCC, and TXNRD1 upregulation abated the repressive function of miR-490-5p by increasing cell growth, monbility and glycolysis and decreasing apoptosis in ESCC cells.…”

“…In this study, we found that circFNDC3B may interact with miR-490-5p, however, whether circFNDC3B can act as a sponge molecule for miR-490-5p is unclear. Thioredoxin reductase 1 (TXNRD1) acts as a tumor promoter in ESCC [ 23 ]. TXNRD1 has been predicted to be a downstream target of miR-490-5p, but whether miR-490-5p can target TXNRD1 to affect ESCC remains poorly documented.…”

The expression of circ_0090049 in hepatocellular carcinoma and the molecular regulation mechanism of other biological functions

“…It is the sixth most common malignant tumor in the world, with high mortality, difficult treatment and poor surgical prognosis. More and more reports have shown that circRNAs, as an endogenous noncoding RNA, play an indispensable role numerous cancers, such as breast cancer [28], ovarian cancer [29], esophageal cancer [30], and liver cancer [31]. However, circ_0090049 has been relatively poorly studied in cancer.…”