Circ_0001686 knockdown suppresses tumorigenesis and enhances radiosensitivity in esophagus cancer through regulating miR-876-5p/SPIN1 axis

Gene expression profiling of SPIN1 in gastric cancer: insights into tumorigenesis and potential therapeutic targets

Background

Gastric cancer (GC) is a prevalent malignant tumor globally, posing a significant threat to human health. The histone code reader Spindlin1 (SPIN1) has been implicated in tumorigenesis and tumor progression, however, the exact molecular mechanisms underlying these processes remain incompletely understood. The biological function and regulatory mechanisms of SPIN1 in GC remain ambiguous. This study aims to investigate the regulatory mechanisms of SPIN1 in the pathogenesis and progression of GC, as well as to identify genes closely associated with SPIN1 and potential biomarkers.

Methods

Gene expression profiles from 375 patients diagnosed with gastric cancer (GC) and 32 control subjects were obtained from the TCGA-STAD database. Our study examined the relationships between SPIN1 expression and various factors including tumor progression, clinical stage, survival status, immune microenvironment and drug sensitivity within the cohort of 375 GC patients and 32 controls. Furthermore, we investigated the interplay between m6A and 5 mC regulators in influencing the expression of SPIN1 in GC, and identified genes with significant correlations with SPIN1 through Spearman correlation analysis.

Results

A significantly elevated expression of SPIN1 was found in 375 GC patients compared to 32 control subjects. SPIN1 expression was positively correlated with EMT score and angiogenesis score. Cell proliferation-related gene sets (myogenesis, mitotic spindle and G2M checkpoint) were all significantly associated with the high SPIN1 GC group. Eosinophils was associated with high expression of SPIN1. A total of 21 checkpoints were associated with SPIN1 expression. Low SPIN1 expression group could benefit from Axitinib, Cytarabine, Pazopanib and Sunitinib. Most m6A regulators and a subset of m5C regulators were positively associated with SPIN1. Finally, we screened the 10 genes with the strongest correlation with SPIN1, among which CDH11 and SLC8A1 were associated with the prognosis of GC.

Conclusion

In conclusion, our study has provided valuable insights into the pivotal role of SPIN1 in GC development, elucidating its potential molecular mechanisms and establishing it as a promising therapeutic target.

SPIN1 accelerates tumorigenesis and confers radioresistance in non-small cell lung cancer by orchestrating the FOXO3a/FOXM1 axis

Despite the importance of radiation therapy as a nonsurgical treatment for non-small cell lung cancer (NSCLC), radiation resistance has always been a concern because of poor patient response and outcomes. Therefore, it is crucial to identify novel targets to increase the effectiveness of radiotherapy and investigate the mechanisms underlying radioresistance. Previously, we demonstrated that Spindlin 1 (SPIN1) was related to tumour initiation and progression. In this study, we found that SPIN1 expression was higher in NSCLC tissues and cell lines than in the corresponding controls. SPIN1 overexpression in NSCLC patients was closely correlated with disease progression and poor prognosis. Functionally, SPIN1 depletion inhibited cell proliferation, decreased the percentage of cells in the G2/M phase and suppressed cell migration and invasion. Moreover, SPIN1 knockdown decreased the clonogenic capacity, impaired double-strand break (DSB) repair and increased NSCLC radiosensitivity. Mechanistically, forkhead box M1 (FOXM1) was identified as a key downstream effector of SPIN1 in NSCLC cells. Furthermore, SPIN1 was found to facilitate MDM2-mediated FOXO3a ubiquitination and degradation, leading to FOXM1 upregulation. Moreover, restoration of FOXM1 expression markedly abolished the inhibitory effects and increased radiosensitivity induced by SPIN1 depletion. These results indicate that the SPIN1-MDM2-FOXO3a/FOXM1 signalling axis is essential for NSCLC progression and radioresistance and could serve as a therapeutic target for increasing radiotherapy efficacy.

Circ-POSTN promotes the progression and reduces radiosensitivity in esophageal cancer by regulating the miR-876-5p/FYN axis

BACKGROUND

Circular RNAs (circRNAs) play critical roles in the tumorigenesis and radiosensitivity of multiple cancers. Nevertheless, the biological functions of circRNA periostin (circ-POSTN) in esophageal cancer (EC) progression and radiosensitivity have not been well elucidated.

METHODS

The expression of circ-POSTN, microRNA-876-5p (miR-876-5p), and proto-oncogene tyrosine-protein kinase (FYN) was analyzed by quantitative reverse transcription PCR (RT-qPCR). Cell proliferation was assessed by MTT, colony formation, and 5-ethynyl-2'-deoxyuridine (EDU) assays. All protein levels were detected by western blot assay. Cell apoptosis and invasion were assessed by flow cytometry analysis and transwell assay, respectively. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were used to validate the interaction between miR-876-5p and circ-POSTN or FYN. The role of circ-POSTN in vivo was explored by establishing mice xenograft model.

RESULTS

Circ-POSTN was overexpressed in EC tissues and cells. Knockdown of circ-POSTN inhibited cell proliferation and invasion and elevated apoptosis and radiosensitivity in EC cells. MiR-876-5p was a direct target of circ-POSTN, and its knockdown reversed the role of sh-circ-POSTN in EC cells. FYN was a direct target of miR-876-5p, and FYN elevation weakened the effects of miR-876-5p overexpression on the progression and radiosensitivity of EC cells. Moreover, circ-POSTN acted as a miR-876-5p sponge to regulate FYN expression. Circ-POSTN interference also suppressed tumor growth and enhanced radiosensitivity in vivo.

CONCLUSION

Circ-POSTN knockdown inhibited proliferation and invasion, but increased apoptosis and enhanced radiosensitivity in EC cells via modulating miR-876-5p/FYN axis, which might be a potential diagnostic and therapeutic target for EC.

Exosome-transported of circ_0081069 induces SPIN1 production by binding to miR-195-5p to inhibit radiosensitivity in esophageal squamous cell carcinoma

Circ_0081069 plays a key role in tumor growth; however, its effect on radiosensitivity in esophageal squamous cell carcinoma (ESCC) remains unknown. The study is performed to reveal the association of circ_0081069 expression and radiosensitivity in ESCC and the underlying mechanism. Circ_0081069, miR-195-5p, and spindlin 1 (SPIN1) RNA expression were detected by quantitative real-time polymerase chain reaction. Protein expression was checked by Western blot analysis or immunohistochemistry assay. Cell viability, proliferation, cell apoptosis, migration, and invasion were investigated by cell counting kit-8, 5-Ethynyl-29-deoxyuridine, flow cytometry analysis, scratch test, and transwell assays, respectively. The sensitivity of ESCC cells to radiation was investigated by cell colony formation assay. The interactions among circ_0081069, miR-195-5p, and SPIN1 were identified by dual-luciferase reporter assay and RNA Immunoprecipitation assay. Xenograft mouse model assay was performed to determine the effect of circ_0007841 on radiosensitivity in vivo. Circ_0081069 and SPIN1 expression were upregulated, whereas miR-195-5p was downregulated in ESCC tissues, ESCC cells, and radiation-stimulated ESCC cells. Circ_0081069 silencing inhibited ESCC cell proliferation, invasion, and migration but improved cell apoptosis. In addition, circ_0081069 knockdown enhanced ESCC cell radiosensitivity in vitro and in vivo. Circ_0081069 bound to miR-195-5p and regulated radiosensitivity by binding to miR-195-5p in ESCC cells. Moreover, SPIN1, a target of miR-195-5p, rescued miR-195-5p-mediated effects in ESCC cells. Circ_0081069 was secreted from ESCC cells by being packaged into exosomes. Further, circ_0081069-Exo inhibited radiosensitivity in ESCC cells. Exosome-mediated transfer of circ_0081069 induced SPIN1 production by binding to miR-195-5p, further inhibiting radiosensitivity in ESCC.

Hsa_circ_0043603 promotes the progression of esophageal squamous cell carcinoma by sponging miR-1178-3p and regulating AADAC expression

This study aims to investigate the regulatory impact of hsa_circ_0043,603, a circular RNA, on the progression of esophageal squamous cell carcinoma (ESCC), which ranks as the sixth leading cause of global mortality. We evaluated the expression, origin, and localization of hsa_circ_0043,603 in ESCC tumors using qRT-PCR, bioinformatics, and FISH analysis. Functional studies were conducted by manipulating the hsa_circ_0043,603 expression in Eca109 cells through overexpression and silencing plasmids. Additionally, xenografts derived from circ_0043,603-overexpressing Eca109 cells enabled us to investigate tumor growth, proliferation, and apoptosis. Through Starbase analysis, we identified miR-1178-3p as a target of circ_0043,603, which was validated using RIP and luciferase assays. Furthermore, we predicted arylacetamide deacetylase (AADAC) as a target of miR-1178-3p and examined its expression in ESCC tissues using Western blot. Lastly, we performed AADAC silencing and overexpression in Eca109 cells to study their impact on cellular phenotypic features, apoptosis, and their interaction with miR-1178-3p mimics and inhibitors. The low expression of hsa_circ_0043,603 in ESCC tissue was associated with poor prognosis. Overexpression of hsa_circ_0043,603 inhibited ESCC growth, invasion, migration, and proliferation, while promoting apoptosis in vitro and suppressing tumor growth in vivo. hsa_circ_0043,603 achieved these effects by targeting the oncogenic miR-1178-3p. Furthermore, AADAC was identified as a target of miR-1178-3p, and its reduced expression was confirmed in ESCC tissues. Overexpression of AADAC in Eca109 cells resulted in suppressed cell growth, proliferation, migration, and invasion by regulating miR-1178-3p. hsa_circ_0043,603 acts as a sponge for miR-1178-3p, leading to the regulation of AADAC expression and inhibition of ESCC development. These results suggest the potential of hsa_circ_0043,603 as a therapeutic and diagnostic target for ESCC.