The circRNA circADAMTS6 promotes progression of ESCC and correlates with prognosis

Hsa_circ_0008667 promotes progression and improves the prognosis of gastric cancer by inhibiting miR-9-5p

BACKGROUND AND STUDY AIM

Gastric cancer (GC) is one of the most common gastrointestinal tumors characterized by aggressive development and poor prognosis. Circular RNAs (circRNAs) have been used as prognostic biomarkers and therapeutic targets in many cancers, including GC. Hsa_circ_0008667 is differentially expressed in GC; however, its function and clinical significance remained unelucidated. Therefore, this study aimed to investigate the role and significance of hsa_circ_0008667 in GC and its potential as a biomarker and therapeutic target of GC.

PATIENTS AND METHODS

Through quantitative reverse-transcription real-time PCR, hsa_circ_0008667 expression in GC tissues and cells were analyzed, followed by statistical analyses to assess the clinical significance. Cell Counting Kit-8 and Transwell assays were performed to examine the effects of hsa_circ_0008667 silencing on GC cell growth and metastasis. Additionally, correlation analysis was performed to assess the relationship between hsa_circ_0008667 and miR-9-5p, which was further validated through luciferase reporter assay.

RESULTS

Hsa_circ_0008667 was considerably upregulated and tightly correlated with lymph node metastasis and the tumor-node-metastasis stage, which was predictive of poor prognosis in patients with GC. Hsa_circ_0008667 silencing suppressed GC cell proliferation, migration, and invasion. Furthermore, hsa_circ_0008667 negatively regulated miR-9-5p expression. MiR-9-5p downregulation enhanced GC malignancy and reversed hsa_circ_0008667 knockdown-mediated GC suppression.

CONCLUSION

The findings of this study suggest hsa_circ_0008667 to be a prognostic biomarker and tumor promoter of GC via miR-9-5p modulation.

Non‑coding RNA: A promising diagnostic biomarker and therapeutic target for esophageal squamous cell carcinoma (Review)

Esophageal cancer (EC) is a common form of malignant tumor in the digestive system that is classified into two types: Esophageal squamous cell carcinomas (ESCC) and esophageal adenocarcinoma. ESCC is known for its early onset of symptoms, which can be difficult to identify, as well as its rapid progression and tendency to develop drug resistance to chemotherapy and radiotherapy. These factors contribute to the high incidence of disease and low cure rate. Therefore, a diagnostic biomarker and therapeutic target need to be identified for ESCC. Non-coding RNAs (ncRNAs) are a class of molecules that are transcribed from DNA but do not encode proteins. Initially, ncRNAs were considered to be non-functional segments generated during transcription. However, with advancements in high-throughput sequencing technologies in recent years, ncRNAs have been associated with poor prognosis, drug resistance and progression of ESCC. The present study provides a comprehensive overview of the biogenesis, characteristics and functions of ncRNAs, particularly focusing on microRNA, long ncRNAs and circular RNAs. Furthermore, the ncRNAs that could potentially be used as diagnostic biomarkers and therapeutic targets for ESCC are summarized to highlight their application value and prospects in ESCC.

IGF2BP2-m6A-circMMP9 axis recruits ETS1 to promote TRIM59 transcription in laryngeal squamous cell carcinoma

Laryngeal squamous cell carcinoma (LSCC) is a common malignancy of the head and neck. Recently, circular RNA (circRNA) has been studied extensively in multisystem diseases. However, there are few research on biological functions and molecular mechanisms of circRNAs in LSCC. CircRNA array was used to detect the differentially expressed circRNAs. Kaplan-Meier and cox regression analysis were used to identify survival based on circMMP9. The qRT-PCR, RNase R treatment, sanger sequencing and in situ hybridization were used to verify circMMP9 expression, characteristics and localization in LSCC tissues and cells. Functionally, colony formation, MTS, transwell and in vivo assays were proceeded to detect the biological function of circMMP9 in LSCC progression. The RNA-seq was conducted to identify the molecular targets of circMMP9. Mechanically, MeRIP, RNA Immunoprecipitation (RIP), RNA pulldown, Chromatin immunoprecipitation (ChIP) and dual-luciferase reporter assays were carried on to verify the regulatory mechanism of circMMP9. CircMMP9 was discovered upregulated in LSCC tissues and cells, and high level of circMMP9 was associated with poor prognosis, low degree of pathological grading, high TNM stage and lymph node metastasis of LSCC. CircMMP9 knockdown prevented LSCC progression both in vitro and in vivo, whereas, circMMP9 overexpression had the opposite effect. CircMMP9 was stabilized by IGF2BP2 in m6A-dependent manner. TRIM59 was identified as downstream target of circMMP9. CircMMP9 recruited ETS1 to stimulate TRIM59 transcription. Moreover, TRIM59 accelerated LSCC progression via activating the PI3K/AKT signal pathway. Our findings offered a unique regulatory mechanism for circMMP9 in LSCC, as well as a novel proof that circMMP9 may be utilize as a diagnostic marker and therapeutic target for LSCC patients.

A novel link between circPDE3B and ferroptosis in esophageal squamous cell carcinoma progression

AIM

To unravel whether ferroptosis involves with the actions by circPDE3B-mediated facilitation of esophageal squamous cell carcinoma (ESCC) progression.

METHODS

Human ESCC tissues and cell lines were prepared for the evaluation of ferroptosis. Cellular iron, ROS, GSH, and MDA levels were measured to assess ferroptosis. Flow cytometry was employed to analyze apoptosis and cell cycle. Subcellular fractionation and fluorescence in situ hybridization (FISH) were conducted to validate the localization of circPDE3B. RNA pull-down, RNA immunoprecipitation (RIP), and luciferase assay were subjected to identify the molecular mechanisms. Nude mouse xenograft model was carried out to evaluate the function of circPDE3B/SLC7A11/CBS in vivo.

RESULTS

Increased circPDE3B in human ESCC specimens was positively correlated with ferroptosis-related molecules, SLC7A11 and CBS. Functionally, circPDE3B knockdown triggered ferroptosis, apoptosis, and cell cycle arrest in ESCC cells. Whereas, these effects were obviously blocked by miR-516b-5p inhibitor. Mechanistically, not only circPDE3B sponged miR-516b-5p to upregulate CBS, but also directly bound with HNRNPK to stabilize SLC7A11. In mice, depletion of circPDE3B restrained ESCC growth, while this was abolished by overexpression of CBS or SLC7A11.

CONCLUSION

In summary, circPDE3B promotes ESCC progression by suppressing ferroptosis through recruiting HNRNPK/SLC7A11 and miR-516b-5p/CBS axes.

CircRNA mannosidase alpha class 1A member 2 promotes esophageal squamous cell carcinoma progression by regulating C-C chemokine ligand 5

Esophageal squamous cell carcinoma (ESCC) is a common malignancy with high morbidity and mortality. Although circular RNAs (circRNAs) play important roles in various cancers including ESCC, the role of the circRNA mannosidase alpha class 1A member 2 (circMAN1A2) in ESCC has been rarely studied. This study aimed to explore the role of circMAN1A2 in ESCC. CircMAN1A2 expression in ESCC tissues and cells was evaluated, and the relationship between circMAN1A2 expression and prognosis in patients with ESCC was analyzed. C-C chemokine ligand 5 (CCL5) was found to be a downstream target of circMAN1A2 by analysing the Agilent Microarray. Next, we performed in vitro and in vivo xenotransplantation assays to explore the role of circMAN1A2 in ESCC. We observed that high circMAN1A2 expression is associated with poor prognosis in patients with ESCC. Suppression of circMAN1A2 expression inhibits the proliferation, migration, and invasiveness of ESCC via regulating CCL5. Our results suggest that circMAN1A2 can promote the progression of ESCC by regulating CCL5. Thus, circMAN1A2 might be a novel diagnostic biomarker of ESCC, and targeting circMAN1A2 using inhibitors could be a potential therapeutic strategy to treat ESCC.

ADAMTS6: Emerging roles in cardiovascular, musculoskeletal and cancer biology

ADAMTS family members control mammalian development and disease, primarily through their function as proteases, by regulation of extracellular matrix composition. Until recently, ADAMTS6 was known as one of the orphan proteinases of the nineteen-member family with a relatively unknown expression pattern and function. Emerging focus on this enzyme has started to uncover these unknowns and revealed a vast importance and requirement of ADAMTS6 in cardiovascular and musculoskeletal development. In addition, ADAMTS6 has been linked to numerous disease settings including several types of cancer. This review summarizes the necessity of ADAMTS6 during development, its role in disease and requirement for essential prospective studies to fully realize its biological implications and potential for therapeutic intervention.