Hsa_circ_0087862 contributes to the progression of colorectal cancer through regulating miR-512-3p/HK2 axis.

Colorectal cancer (CRC) theratened thousands of people every year. Emerging evidences suggested that circular RNAs (circRNAs) were involved in CRC malignancies. However, the underlying mechanisms have yet not been revealed. Quantitative real-time PCR (qRT-PCR) was used to determine the expression of circ_0087862 and microRNA-512-3p (miR-512-3p). Western blot was performed to measure the protein expression of hexokinase 2 (HK2), B-cell lymphoma-2 (Bcl-2), BCL2-associated X (Bax) and BCL2 antagonist/killer 1 (Bak). Moreover, 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay, colony formation and 5-ethynyl-2'-deoxyuridine (EdU) assay were employed to assess CRC cell proliferation. Also, migration/invasion abilities and apoptosis rates were investigated by transwell assay and flow cytometry. Glucose consumption, lactate production and ATP production were detected using the corresponding kits. Dual-luciferase reporter analysis and RNA immunoprecipitation (RIP) experiments were utilized to analyze the target association of miR-512-3p and circ_0087862 or HK2. Finally, xenograft assay was carried out to analyze the function of circ_0087862 in tumor growth in vivo. Circ_0087862 expression was elevated in CRC tissues and cells. Circ_0087862 silencing repressed cell viabilities, proliferation, migration/invasion and glycolysis, and reinforced cell apoptosis. However, HK2 could weaken these impacts. Additionally, miR-512-3p targeted HK2, and circ_0087862 could regulate HK2 expression by miR-512-3p. Furthermore, circ_0087862 silencing decreased CRC cell xenograft tumor growth. Collectively, our data suggested that circ_0087862 knockdown impeded cell viabilities, proliferation, and glycolysis, and contributed to cell apoptosis in CRC, indicating circ_0087862 as a promising tumor promoter.

Chen Y ，Chen L ，Wu J ，Su D ... -  《-》

Circ-FOXM1 contributes to cell proliferation, invasion, and glycolysis and represses apoptosis in melanoma by regulating miR-143-3p/FLOT2 axis.

Tian S ，Han G ，Lu L ，Meng X ... -  《World Journal of Surgical Oncology》

Circ_0087862 promotes tumorigenesis and glycolysis in colorectal cancer by sponging miR-296-3p to regulate PGK1 expression.

Circular RNAs (circRNAs) exert crucial roles in tumor progression of multiple cancers, including colorectal cancer (CRC). However, the functions of most circRNAs are not been fully elucidated. In this study, the role and mechanism of circ_0087862 in CRC were investigated. The expression of circ_0087862, microRNA-296-3p (miR-296-3p) and phosphoglycerate kinase 1 (PGK1) was detected by quantitative real-time PCR (qRT-PCR). Cell Counting Kit-8 (CCK-8) assay and 5-ethynyl-2'-deoxyuridine (EdU) assay were used to assess cell proliferation. Flow cytometry was employed to analyze cell apoptosis. Transwell assay was employed to evaluate cell invasion. Western blot assay was employed to detect the level of related protein markers and PGK1. The glucose consumption, lactate production were tested by corresponding kits. The relationship between miR-296-3p and circ_0087862 or PGK1 was verified by dual-luciferase reporter assay or RNA immunoprecipitation (RIP) assay. The in vivo function of circ_0087862 was examined by xenograft mice model. The expression levels of circ_0087862 and PGK1 were up-regulated in CRC tissues and cells, while miR-296-3p was down-regulated. Circ_0087862 silencing suppressed cell proliferation, invasion and glycolysis and promoted cell apoptosis in CRC cells. Circ_0087862 targeted miR-296-3p in CRC cells. MiR-296-3p inhibition reversed circ_0087862 silencing-mediated inhibition effect on cell proliferation, invasion and glycolysis, as well as the promotion effect on cell apoptosis. PGK1 was a target of miR-296-3p, and the overexpression of PGK1 attenuated miR-296-3p-mediated tumor suppression effect on CRC progression. Moreover, knockdown of circ_0087862 inhibited tumorigenesis in vivo. Circ_0087862 promoted CRC progression via miR-296-3p/PGK1 axis and might act as a potential target for CRC therapy.

Xiao W ，Li P 《-》

Hsa_circ_0045932 regulates the progression of colorectal cancer by regulating HK2 through sponging miR-873-5p.

Circular RNAs (circRNAs) have been confirmed to be key regulators for colorectal cancer (CRC) progression. The purpose of this research was to explore the biological role and mechanism of hsa_circ_0045932 in CRC. RT-qPCR and Western blot (WB) were applied to examine RNA and protein levels, respectively. MTT assay, EdU assay, and transwell assay were used to detect cell proliferative, migration, and invasion. Glucose uptake and lactic acid level were determined to assess cellular glycolysis. Dual-luciferase reporter and RIP assays were carried out to detect the relationship between miR-873-5p and hsa_circ_0045932 or hexokinase 2 (HK2). Xenograft mice model was established to confirm the function of hsa_circ_0045932 in vivo. Hsa_circ_0045932 was overexpressed in CRC tissue samples and cells. Hsa_circ_0045932 knockdown repressed CRC cell proliferation, invasion, migration, and glycolysis abilities in vitro. MiR-873-5p could be sponged by hsa_circ_0045932, and its inhibitor also reversed the inhibitory effect of hsa_circ_0045932 knockdown on CRC cell progression. HK2 was targeted by miR-873-5p, and hsa_circ_0045932 regulated HK2 expression through targeting miR-873-5p. Overexpression of HK2 reversed the repressive effect of hsa_circ_0045932 knockdown on CRC cell malignant behaviors. Furthermore, the pro-tumor role of hsa_circ_0045932 in vivo was also confirmed using animal experiments. Hsa_circ_0045932 promoted CRC progression through sponging miR-873-5p to up-regulate HK2, which might offer novel therapeutic target for CRC clinical intervention.

Hong F ，Deng Z ，Tie R ，Yang S ... -  《-》

Circ-ACAP2 facilitates the progression of colorectal cancer through mediating miR-143-3p/FZD4 axis.

Circular RNAs (circRNAs) play crucial roles in multiple cancers, including colorectal cancer (CRC). Here, we explored the role of circRNA ArfGAP with coiled-coil, ankyrin repeat and PH domains 2 (circ-ACAP2) in the progression and radioresistance of CRC. Quantitative real-time polymerase chain reaction (qPCR) and Western blot assay were used to detect RNA and protein expression, respectively. The proliferation, apoptosis, migration, invasion and radioresistance of CRC cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry, transwell migration assay, transwell invasion assay and colony formation assay. The target interaction between microRNA-143-3p (miR-143-3p) and circ-ACAP2 or frizzled class receptor 4 (FZD4) was verified by dual-luciferase reporter assay. Murine xenograft model was established to explore the role of circ-ACAP2 in vivo. The expression of circ-ACAP2 was prominently enhanced in CRC tissues and cell lines. Circ-ACAP2 facilitated the proliferation, migration, invasion and radioresistance whereas inhibited the apoptosis of CRC cells. MiR-143-3p was a direct target of circ-ACAP2 in CRC cells. Circ-ACAP2 promoted the progression and radioresistance of CRC partly by sponging miR-143-3p. MiR-143-3p interacted with the 3' untranslated region (3'UTR) of FZD4 in CRC cells, and FZD4 overexpression partly reversed miR-143-3p-mediated effects in CRC cells. Wnt/β-catenin signalling was modulated by circ-ACAP2/miR-143-3p/FZD4 axis in CRC cells. Circ-ACAP2 contributed to the development and radioresistance of CRC partly through targeting miR-143-3p/FZD4 axis, which provided novel potential diagnostic and therapeutic targets for CRC.

Zhang G ，Liu Z ，Zhong J ，Lin L ... -  《-》