Circular RNA hsa_circ_0000700 promotes cell proliferation and migration in Esophageal Squamous Cell Carcinoma by sponging miR-1229

Abstract

Accumulating evidence has demonstrated that circular RNAs (circRNAs) are involved in the pathogenesis of cancer, including that of esophageal squamous cell carcinoma (ESCC). The current study aimed to investigate the role of hsa_circ_0000700 in ESCC. hsa_circ_0000700, miR-1229, and related functional gene expression was measured by RT-qPCR. To characterize the functions of hsa_circ_0000700 and miR-1229, ESCC cells were infected with hsa_circ_0000700-specific siRNA, miR-1229 mimics, and an inhibitor alone or in combination. Cell Counting Kit-8 (CCK8), colony formation, EdU, flow cytometry, and Transwell assays were employed to evaluate cell proliferation, apoptosis, and migration. Luciferase reporter and RNA immunoprecipitation assays were used to confirm the targeting relationship between hsa_circ_0000700 and miR-1229. Finally, a competing endogenous RNAs (ceRNA) network was built for hsa_circ_0000700, and miR-1229 targets were analyzed by bioinformatics. circ_0000700 expression was significantly upregulated in ESCC cell lines. Actinomycin D and RNase R treatment confirmed that circ_0000700 was more stable than its linear CDH9 mRNA form. Moreover, a cytoplasmic and nuclear fractionation assay suggested that circ_0000700 was mainly distributed in the cytoplasm of ECA-109 and TE-1 cells. In vitro, the proliferative and migratory capacities of ECA-109 and TE-1 cells were inhibited by knocking down circ_0000700 expression. Additionally, miR-1229 silencing reversed the circ_0000700-specific siRNA-induced attenuation of malignant phenotypes. Mechanistically, circ_0000700 was identified as a sponge of miR-1229 and could activate PRRG4, REEP5, and PSMB5 indirectly to promote ESCC progression. In summary, our results suggest that hsa_circ_0000700 functions as an oncogenic factor by sponging miR-1229 in ESCC.

Circ_0005231 promotes the progression of esophageal squamous cell carcinoma via sponging miR‐383‐5p and regulating KIAA0101

“… 22 Moreover, the proliferative and migratory capacities of ESCC cells were decreased and apoptosis was increased by hsa_circ_0000700 knockdown. 23 In this study, a novel upregulated circRNA named circ_0005231 was identified based on the GEO database, and we further confirmed the level of circ_0005231 was remarkably upregulated in ESCC plasma, tissues and cells. Next, we knocked down circ_0005231 expression and evaluated the effects on ESCC cell behavior.…”

PSMB5 overexpression is correlated with tumor proliferation and poor prognosis in hepatocellular carcinoma

“…Wang et al [7] revealed that the downexpression of PSMB5 significantly inhibited the proliferation and migration of breast cancer cells both in vitro and in vivo. Fang et al [13] demonstrated that hsa_circ_0000700 could activate PSMB5 indirectly to enhance esophageal squamous cell carcinoma proliferation. These findings suggest an oncogenic role of PSMB5, which is consistent with our research results.…”

“…In addition, the tumor‐promoting role of PSMB5 has been reported in relation to many human cancers, such as breast cancer, esophageal squamous cell carcinoma and prostate cancer. Aberrant expression of PSMB5 is correlated to tumor cell proliferation metastasis and drug resistance [ 7 , 11 , 12 , 13 , 14 ]. However, as for a subunit of the whole proteasome complex, the functional role and biological mechanism of PSMB5 in HCC still remain largely unknown.…”

Knockdown circ_0040414 inhibits inflammation, apoptosis and promotes the proliferation of cardiomyocytes via miR‐186‐5p/PTEN/AKT axis in chronic heart failure

“…For RNase R treatment, the total RNA of 2 μg was extracted from AC16 cells and incubated with or without 3 U/μg of RNase R (Epicentre) for 15 min at 37°C. Circ_0040414 and Linear 0040414 level was quantified using RT-qPCR (Fang et al, 2021).…”