Hsa_circ_0075960 Serves as a Sponge for miR-361-3p/SH2B1 in Endometrial Carcinoma

Circ_CHMP5 aggravates oxidized low-density lipoprotein-induced damage to human umbilical vein endothelial cells through miR-516b-5p/TGFβR2 axis

BACKGROUND

Atherosclerosis (AS) was one of the main causes of death in the elderly, and lesions in human umbilical vein endothelial cells (HUVECs) could lead to AS. CircRNA-charged multivesicular body protein 5 (circ_CHMP5) was reported to participate in the progression of AS.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was used to analyze the levels of circ_CHMP5, miR-516b-5p, and transforming growth factor beta receptor 2 (TGFβR2) in AS patients or ox-LDL-induced HUVECs. 5-Ethynyl-2'-deoxyuridine and cell counting kit-8 assays were performed to detect cell proliferation. Proteins expression was assessed by western blot assay. Cell apoptosis was examined by flow cytometry. Tube formation assay was utilized to measure the tube formation ability of HUVCEs. The targeting relationships between miR-516b-5p and circ_CHMP5 or TGFβR2 were confirmed by dual-luciferase reporter assay and RNA-pull down assay.

RESULTS

Circ_CHMP5 was enhanced in the serum of AS patients and ox-LDL-exposure HUVECs. Ox-LDL blocked proliferation and tube formation of HUVECs and induced cell apoptosis, and circ_CHMP5 knockdown reversed these effects. In addition, circ_CHMP5 regulated the growth of ox-LDL-induced HUVECs through miR-516b-5p and TGFβR2. Moreover, the effects of circ_CHMP5 knockdown on ox-LDL-induced HUVECs were obviously recovered by downregulation of miR-516b-5p, and overexpression of TGFβR2 restored the effects of miR-516b-5p upregulation on ox-LDL-stimulated HUVECs.

CONCLUSION

Silence of circ_CHMP5 overturned ox-LDL-treated inhibition of HUVECs proliferation and angiogenesis by miR-516b-5p and TGFβR2. These results provided new solutions for the treatment of AS.

LncRNA BBOX1-AS1 Contributes to the Progression of Esophageal Carcinoma by Targeting the miR-361-3p/COL5A1 Axis

Long noncoding RNAs (lncRNAs) are known to participate in the progression of several cancers, including esophageal carcinoma (EC), a common malignancy of the digestive system. Although the role of the lncRNA-miRNA-mRNA regulatory network is crucial for the growth and progression of EC, the regulation of lncRNA BBOX1-AS1 (BBOX1 antisense RNA1) remains unclear. We performed reverse transcription-quantitative PCR (RT-qPCR) and western blotting to evaluate miR-361-3p, collagen type V alpha 1 chain (COL5A1), and BBOX1-AS1 expression levels in EC cells and tissues. The colony formation assay (CFA) and Cell Counting Kit-8 (CCK-8) were employed to identify EC cell proliferation, while western blotting was used to examine EC cell apoptosis and Bax and Bcl-2 expression levels. The effect of BBOX1-AS1 on EC proliferation was determined using an in vivo carcinogenesis assay. Correlation between COL5A1, BBOX1-AS1, and miR-361-3p was examined using the luciferase reporter system and RNA immunoprecipitation assay (RIP). Herein, we observed that BBOX1-AS1 expression levels were upregulated in EC cells and tissues. BBOX1-AS1 knockdown inhibited EC cell proliferation and conferred a pro-apoptotic effect. These results indicated a positive interaction between BBOX1-AS1 and miR-361-3p in EC and a negative association with miR-361-3p. COL5A1 was recognized as a downstream miR-361-3p target and was inversely related to miR-361-3p in EC. Therefore, BBOX1-AS1 expression suppressed cell apoptosis and promoted cell proliferation via the downregulation of miR-361-3p and upregulation of COL5A1 expression. Overall, BBOX1-AS1 facilitates EC progression via the miR-361-3p or COL5A1 axis, indicating that BBOX1-AS1 might be a potential therapeutic target for EC therapy.

Circ_0044556 Promotes the Progression of Colorectal Cancer via the miR-665-Dependent Expression Regulation of Diaphanous Homolog 1

BACKGROUND

Cancer progression can be regulated by noncoding circular RNAs. A recent study has indicated that circ_0044556 facilitated the progression of colorectal cancer.

AIM

This research was performed to explore the regulatory mechanism of circ_0044556 in CRC.

METHODS

Circ_0044556, miR-665 and Diaphanous Homolog 1 levels were detected by the quantitative real-time polymerase chain reaction. Cell proliferation analysis was performed by cell counting kit-8 assay and Edu assay. Cell cycle progression was assessed using flow cytometry. The protein examination was conducted using western blot. Transwell assay was used to analyze cell migration and invasion. Dual-luciferase reporter assay was performed to validate the interaction between targets. In vivo research was implemented by xenograft tumor assay.

RESULTS

Circ_0044556 was upregulated in colorectal cancer samples and cells. Silencing circ_0044556 inhibited cell proliferation, cell cycle progression, migration, invasion, and epithelial-mesenchymal transition in CRC cells. Circ_0044556 could directly target miR-665 and the function of circ_0044556 was associated with the regulation of miR-665. In addition, Diaphanous Homolog 1 was a target gene for miR-665 and the anti-tumor role of miR-665 in colorectal cancer was dependent on the downregulation of Diaphanous Homolog 1. Diaphanous Homolog 1 level was regulated by circ_0044556 via sponging miR-665 in CRC cells. In vivo assay suggested that circ_0044556 promoted CRC tumor growth by regulating the miR-665 and Diaphanous Homolog 1 levels.

CONCLUSION

Our findings manifested that circ_0044556 functioned as an oncogenic circRNA in colorectal cancer by mediating the miR-665/Diaphanous Homolog 1 axis, elucidating the molecular mechanism of circ_0044556 in CRC progression.

LncRNA GATA3-AS1 promoted invasion and migration in human endometrial carcinoma by regulating the miR-361/ARRB2 axis

Endometrial carcinoma (EC) is a kind of fatal female malignancy. lncRNA GATA3-AS1 has been identified as an oncogene in various cancers. However, the functions and mechanisms of GATA3-AS1 in EC remain to be explored. Human EC tissues and four EC cell lines were used. Western blotting and quantitative real-time PCR (qRT-PCR) were used to evaluate the expression of GATA3-AS1, miR-361, and ARRB2. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were used to validate the interaction among GATA3-AS1, miR-361, and ARRB2. Flow cytometry, colony formation assay, scratch assay, and transwell assay were used to examine the cell apoptosis, proliferation, migration, and invasion of EC cells, respectively. In vivo tumor growth was monitored in nude mice. GATA3-AS1 and ARRB2 were upregulated while miR-361 was downregulated in human EC tissues and EC cells. GATA3-AS1 knockdown constrained cell proliferation, invasion, migration, and EMT while promoting the apoptosis of EC cells by upregulating miR-361. GATA3-AS1 negatively regulated miR-361 expression. ARRB2 was the direct target of miR-361 and could activate the Src/Akt pathway. In vivo, GATA3-AS1 knockdown suppressed tumor progression by upregulating the miR-361 expression. lncRNA GATA3-AS1 promoted EC invasion and migration by the miR-361/ARRB2 axis, which indicated that GATA3-AS1 might be a promising therapeutic option for advanced EC progression. KEY MESSAGES: GATA3-AS1 knockdown suppressed EC proliferation, invasion, and migration. GATA3-AS1 directly inhibited miR-361 as a ceRNA. MiR-361 knockdown reversed the tumor suppressive effect caused by GATA3-AS1 knockdown. MiR-361 bound to ARRB2 directly and suppressed its expression. The GATA3-AS1/miR-361/ARRB2 axis regulated EC cell proliferation, invasion, and migration.

Circular RNA hsa_circ_0011324 is involved in endometrial cancer progression and the evolution of its mechanism

Endometrial cancer (EC) is one of the most common gynecological tumors with an increasing incidence. CircRNA plays an essential regulatory role in EC. Our objective was to investigate the potential mechanism of circRNAs derived SPOC Domain Containing 1 (SPOCD1) in EC progression. Seven circRNAs from SPOCD1 were analyzed by circBase and their expression was verified by quantitative real-time polymerase chain reaction. Only the expression of hsa_circ_0011324 was significantly increased in cancer tissues. The cell lines Ishikawa and RL95-2 which interfered with or overexpressed hsa_circ_0011324 were constructed and cell functions were tested. Results revealed hsa_circ_0011324 overexpression promoted cell proliferation, migration, and invasion; while silence of hsa_circ_0011324 had opposite effect on cell functions. RNA22 website and Targetscan website were applied to analyze downstream genes regulated by hsa_circ_0011324. Then, the expression of downstream genes was detected in EC tissues. Results indicated hsa-miR-497/16-5p expression were down-regulated, and mechanistic target of rapamycin kinase (mTOR) was up-regulated in EC. Furthermore, hsa_circ_0011324 regulated mTOR expression and cell functions by affecting hsa-miR-497/16-5p. And the potential mechanism was hsa_circ_0011324 competes with mTOR to directly bind to hsa-miR-497/16-5p. In conclusion, hsa_circ_0011324 could sponge hsa-miR-497/16-5p targeted mTOR to participate in EC progress. Our study may provide a new therapeutic target for EC.

Hsa_circ_0000437 Inhibits the Development of Endometrial Carcinoma through miR-626/CDKN1B Axis

BACKGROUND

Circular RNAs (circRNAs) are pivotal in cancer biology. Nevertheless, the biological functions of circular RNA hsa_circ_0000437 (circ_0000437) have not yet been elucidated. In the present study, we studied the expression characteristics of circ_0000437 in endometrial carcinoma (EC) and explored the roles and potential mechanisms of circ_0000437 in EC progression.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was adopted to detect the expressions of circ_0000437, microRNA-626 (miR-626) and cyclin-dependent kinase inhibitor 1B (CDKN1B) in EC tissues and cells. 5-Ethynyl-2'-deoxyuridine (EdU), cell counting kit-8 (CCK-8) and Transwell assays were performed to evaluate EC cell proliferation and invasion. The expressions of CDKN1B and epithelial-mesenchymal transition (EMT)-related proteins (E-cadherin and N-cadherin) were detected by Western blot. Moreover, the targeted relationship between miR- 626 and circ_0000437 or CDKN1B was determined by a dual-luciferase reporter and RNA immunoprecipitation (RIP) assays.

RESULTS

Circ_0000437 expression was reduced in EC tissues, and the low expression of circ_0000437 was positively correlated with the lymph node metastasis and high TNM stage of EC patients. Knocking down circ_0000437 promoted the proliferation, invasion and EMT of EC cells. Circ_0000437 directly targeted miR-626 and negatively modulated miR-626 expression in EC cells. CDKN1B was identified as the downstream target of miR-626 in EC cells. Besides, CDKN1B overexpression of miR-626 knockdown reversed the effects of knocking down circ_0000437 on EC cells.

CONCLUSION

Circ_0000437 regulates the miR-626/CDKN1B pathway to suppress the proliferation, invasion and EMT of EC cells. This indicates that circ_0000437 may be a promising biomarker and therapy target for EC.