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

Circular RNA circCHSY1 silencing inhibits the malignant progression of esophageal squamous cell carcinoma

BACKGROUND

CircRNAs play a crucial role in the regulation of various cancers. This study aims to investigate the involvement of circCHSY1 in the development of esophageal squamous cell carcinoma (ESCC).

METHODS

RNA levels were quantified using qRT-PCR, and protein levels were measured by western blot. The stability of circCHSY1 was analyzed using RNase R. The functional effect of circCHSY1 on cell behavior was evaluated by CCK-8, EdU, flow cytometry, transwell, tube formation, and xenograft tumor model assays. The associations among circCHSY1, miR-1229-3p, and Tectonic-1 (TCTN1) were certified by bioinformatics analysis, dual-luciferase reporter assay, and RNA pull-down assay.

RESULTS

CircCHSY1 was up-regulated in both ESCC tissues and cell lines in comparison with the control groups. Knockdown of circCHSY1 inhibited the proliferation, migration, invasion, and tube formation and promoted apoptosis of ESCC cells. Mechanistically, circCHSY1 targeted miR-1229-3p, which was downregulated in ESCC tissues and cells. Inhibition of miR-1229-3p attenuated the effects mediated by circCHSY1 suppression. Besides, miR-1229-3p bound to TCTN1, and TCTN1 overexpression restored miR-1229-3p-induced effects in ESCC cells. Animal experiments revealed that circCHSY1 silencing suppressed tumor tumorigenesis in vivo.

CONCLUSION

CircCHSY1 contributed to ESCC cell malignancy, and the underlying mechanism involved the circCHSY1/miR-1229-3p/TCTN1 axis, providing potential therapeutic targets for ESCC.

CircSEMA6A upregulates PRRG4 by targeting MiR-520h and recruiting ELAVL1 to affect cell invasion and migration in papillary thyroid carcinoma

Objective

As the most prevalent type of thyroid malignancy, papillary thyroid carcinoma (PTC) accounts for over 80% of all thyroid cancers. Circular RNAs (circRNAs) have been found to regulate multiple cancers, including PTC.

Materials and methods

Quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were used to analyse RNA and protein levels. Fluorescence in situ hybridization (FISH) was used to detect the distribution of the target genes. Functional experiments and animal experiments were implemented to analyse the biological functions of target genes in vitro and in vivo. Luciferase reporter, RNA pulldown, RNA binding protein immunoprecipitation (RIP) and mRNA stability assays were used to probe the underlying mechanisms.

Results

CircSEMA6Awas found to be upregulated in PTC tissues and cells, and its circular structure was verified. CircSEMA6A promotes PTC cell migration and invasion. Moreover, circSEMA6A functions as a competing endogenous RNA (ceRNA) to upregulate proline rich and Gla domain 4 (PRRG4) expression by sponging microRNA-520h (miR-520h). CircSEMA6A recruits ELAV1 to stabilize PRRG4 mRNA and drives PTC progression via PRRG4.

Conclusion

CircSEMA6A upregulates PRRG4 by targeting miR-520h and recruiting ELAVL1 to affect the invasion and migration of PTC cells, offering insight into the molecular mechanisms of PTC.

Construction of noninvasive prognostic model of bladder cancer patients based on urine proteomics and screening of natural compounds

BACKGROUND

Bladder cancer (BCa) has a high incidence and recurrence rate worldwide. So far, there is no noninvasive detection of BCa therapy and prognosis based on urine multi-omics. Therefore, it is necessary to explore noninvasive predictive models and novel treatment modalities for BCa.

METHODS

First, we performed protein analysis of urine from five BCa patients and five healthy individuals using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Combining multi-omics data to mine particular and sensitive molecules to predict BCa prognosis. Second, urine proteomics data were combined with TCGA transcriptome data to select differential genes that were specifically highly expressed in urine and tissues. Further, the Lasso equation was used to screen specific molecules to construct a noninvasive prediction model of BCa. Finally, natural compounds of specific molecules were selected by combined network pharmacology and molecular docking to complete molecular structure docking.

RESULTS

A noninvasive predictive model was constructed using PSMB5, P4HB, S100A16, GET3, CNP, TFRC, DCXR, and MPZL1, specific molecules screened by multi-omics, and clinical features, which had good predictive value at 1, 3, and 5 years of prediction. High expression of these target genes suggests a poor prognosis in patients with BCa, and they were mainly involved in cell adhesion molecules and the IGF pathway. In addition, the corresponding drugs and natural compounds were selected by network pharmacology, and the molecular structure 7NHT of PSMB5 was found to be well docked to Ellagic acid, a natural compound in Hetaoren that we found. The 3D structure 6I7S of P4HB was able to bind to Stigmasterol in Shanzha stably, and the structure 6WRV of TFRC as an iron transport carrier was also able to bind to Stigmasterol in Shanzha stably. The structures 1WOJ, 3D3W, and 6IGW of CNP, DCXR, and MPZL1 can also play an important role in combination with the natural compounds (S)-Stylopine, Kryptoxanthin, and Sitosterol in Maqianzi, Yumixu, and Laoguancao.

CONCLUSION

The noninvasive prediction model based on urinomics had excellent potential in predicting the prognosis of patients with BCa. The multi-omics screening of specific molecules combined with pharmacology and compound molecular docking can promote the research and development of novel drugs.

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

Aberrant expression of members of the proteasome subunit beta (PSMB) family (including PSMB2, PSMB4, PSMB7 and PSMB8) has been reported in hepatocellular carcinoma (HCC). However the role of PSMB5 in HCC is unclear. To address this issue, we examined the expression of PSMB5 in HCC tissues using the The Cancer Genome Atlas, International Cancer Genome Consortium and Gene Expression Omnibus databases. A quantitative real-time PCR and immunohistochemistry were performed to validate the expression of PSMB5 in HCC. The survival mutation status and immune cell infiltration of PSMB5 were also evaluated in HCC. We then examined the effect of knocking down PSMB5 expression through RNA interference in the HCC cell line Huh7. High expression of PSMB5 was observed in HCC tissues and was associated with poor prognosis. PSMB5 expression and clinical characteristics were then incorporated to build a prognostic nomogram. We observed that PSMB5 expression was closely related to the abundance of B cells, CD4⁺ T cells, CD8⁺ T cells, dendritic cell macrophages and neutrophils. Moreover silencing of PSMB5 in Huh7 significantly suppressed cell proliferation and migration at the same time as increasing apoptosis. Inhibition of the phosphatidylinositol-3-kinase/Akt/mechanistic target of rapamycin pathway was observed after PSMB5 downregulation in Huh7 cells. Our findings suggest that PSMB5 may promote the proliferation of HCC cells by inactivating the phosphatidylinositol-3-kinase/Akt/mechanistic target of rapamycin signaling pathway and thus PSMB5 may have potential as a biomarker for diagnosis and prognosis of HCC.

Genome-wide CRISPR knockout screening identified G protein pathway suppressor 2 as a novel tumor suppressor for uveal melanoma metastasis

PURPOSE

Uveal melanoma (UM) is the most common intraocular malignant tumor in adults. Due to the lack of effective treatments for metastatic UM, the survival of UM has not changed over the past 3 decades. Therefore, it is important to identify essential genes regulating the metastasis of UM.

METHODS

In this study, a genome-wide CRISPR knockout screen in an orthotopic mouse model of UM was performed to identify the regulatory genes conferring the metastatic phenotype. Loss-of-function analyses were performed to explore the function of G protein pathway suppressor 2 (GPS2) in UM metastasis in vitro and in vivo. RNA sequencing was performed to investigate the molecular mechanism underlying the function of GPS2 as a tumor suppressor in UM.

RESULTS

Among the highest-ranking genes, we found several validated tumor suppressors, such as SHPRH, GPS2, PRPH2, and hsa-mir-1229; GPS2 was chosen as the candidate gene for further studies. GPS2 was lower expressed in the tumor tissues of UM patients. Furthermore, knocking-down GPS2 promoted the proliferation and metastatic abilities of UM cells both in vivo and in vitro. Finally, analysis of the transcriptome data revealed that silencing GPS2 upregulates oncogenic signaling pathways MAPK and PI3K-Akt, and in the meantime downregulates tumor suppressor signaling pathway Slit/Robo in UM cells.

CONCLUSION

Altogether, our study proved that the GPS2 gene functions as a tumor suppressor and might be a novel potential therapeutic target for UM treatment.

Discovery of Anticancer Activity of Amentoflavone on Esophageal Squamous Cell Carcinoma: Bioinformatics, Structure-Based Virtual Screening, and Biological Evaluation

Esophageal squamous cell carcinoma (ESCC) is the most common primary esophageal malignancy with poor prognosis. Here, due to the necessity for exploring potential therapies against ESCC, we obtained the gene expression data on ESCC from the TCGA and GEO databases. Venn diagram analysis was applied to identify common targets. The protein-protein interaction network was constructed by Cytoscape software, and the hub targets were extracted from the network via cytoHubba. The potential hub nodes as drug targets were found by pharmacophore-based virtual screening and molecular modeling, and the antitumor activity was evaluated through in vitro studies. A total of 364 differentially expressed genes (DEGs) in ESCC were identified. Pathway enrichment analyses suggested that most DEGs were mainly involved in the cell cycle. Three hub targets were retrieved, including CENPF, CCNA2 (cyclin A), and CCNB1 (cyclin B1), which were highly expressed in esophageal cancer and associated with prognosis. Moreover, amentoflavone, a promising drug candidate found by pharmacophore-based virtual screening, showed antiproliferative and proapoptotic effects and induced G1 in esophageal squamous carcinoma cells. Taken together, our findings suggested that amentoflavone could be a potential cell cycle inhibitor targeting cyclin B1, and is therefore expected to serve as a great therapeutic agent for treating esophageal squamous cell carcinoma.

Current advances and future perspectives on the functional roles and clinical implications of circular RNAs in esophageal squamous cell carcinoma: more influential than expected

Esophageal squamous cell carcinoma (ESCC) is one of the most aggressive gastrointestinal cancers with high incidence and mortality. Therefore, it is necessary to identify novel sensitive and specific biomarkers for ESCC detection and treatment. Circular RNAs (circRNAs) are a type of noncoding RNAs featured by their covalently closed circular structure. This special structure makes circRNAs more stable in mammalian cells, coupled with their great abundance and tissue specificity, suggesting circRNAs may present enormous potential to be explored as valuable prognostic and diagnostic biomarkers for tumor. Mounting studies verified the critical roles of circRNAs in regulating ESCC cells malignant behaviors. Here, we summarized the current progresses in a handful of aberrantly expressed circRNAs, and elucidated their biological function and clinical significance in ESCC, and introduced a series of databases for circRNA research. With the improved advancement in high-throughput sequencing and bioinformatics technique, new frontiers of circRNAs will pave the path for the development of precision treatment in ESCC.

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

Background

Circular RNAs (circRNAs) can act as key regulators in human cancers, including esophageal squamous cell carcinoma (ESCC). However, the role and mechanism of circ_0005231 in ESCC have not previously been reported.

Methods

RNA levels and protein levels were detected by real‐time quantitative polymerase chain reaction (RT‐qPCR) and Western blot assay, respectively. Cell proliferation was assessed by colony formation assay and 5‐ethynyl‐2'‐deoxyuridine (EdU) assay. Wound healing and transwell assays were used to assess cell migration and invasion, respectively. The intermolecular interaction was predicted by bioinformatic analysis and verified by RNA immunoprecipitation (RIP), RNA pulldown and dual‐luciferase reporter assays. Xenograft tumor model was used for exploring the biological function of circ_0005231 in vivo.

Results

Circ_0005231 was upregulated in ESCC plasma, tissues and cells. Cell proliferation, migration and invasion were significantly restrained by knockdown of circ_0005231 in ESCC cells. Circ_0005231 acted as a sponge of miR‐383‐5p, and circ_0005231 regulated ESCC cellular behavior by sponging miR‐383‐5p. Moreover, miR‐383‐5p directly targeted KIAA0101, and circ_0005231 positively regulated KIAA0101 expression by sponging miR‐383‐5p. Furthermore, circ_0005231 knockdown suppressed the malignant behavior of ESCC cells by downregulating KIAA0101. Importantly, knockdown of circ_0005231 blocked xenograft tumor growth in vivo.

Conclusion

Circ_0005231 acted as a sponge of miR‐383‐5p to promote ESCC progression by upregulating KIAA0101, which provided a potential therapeutic strategy for ESCC treatment.

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

Previous studies have shown that circ_0040414 is highly expressed in the blood of patients with heart failure (HF), which suggests that circ_0040414 is associated with heart failure (HF). However, the functional involvement of circ_0040414 in HF and its potential mechanism remains unclear. Consistent with previous studies, our study showed that the expression of circ_0040414 in the peripheral blood of patients with chronic heart failure (CHF) was significantly higher than that of healthy control, which indicated that circ_0040414 could be used as a diagnostic biomarker in patients with CHF. In cardiomyocytes, circ_0040414 increased the level of proapoptotic proteins Bax, cleaved-caspase 3 and reduced the expression of antiapoptotic protein Bcl-2. It also promoted inflammatory factors IL-6, TNF-α, and IL-β, but inhibited cell proliferation. In terms of mechanism, circ_0040414 upregulated the expression of phosphatase and tensin homolog (PTEN) through sponging miR-186-5p to inhibit AKT signaling activity. Our study uncovered a novel role and the mechanism of circ_0040414 in controlling CHF, enriched the molecular regulatory network in CHF, and may provide a possible strategy for the treatment of CHF.