Autophagy-related gene 7 deficiency caused by miR-154-5p overexpression suppresses the cell viability and tumorigenesis of retinoblastoma by increasing cell apoptosis

Insights on E1-like enzyme ATG7: functional regulation and relationships with aging-related diseases

Autophagy is a dynamic self-renovation biological process that maintains cell homeostasis and is responsible for the quality control of proteins, organelles, and energy metabolism. The E1-like ubiquitin-activating enzyme autophagy-related gene 7 (ATG7) is a critical factor that initiates classic autophagy reactions by promoting the formation and extension of autophagosome membranes. Recent studies have identified the key functions of ATG7 in regulating the cell cycle, apoptosis, and metabolism associated with the occurrence and development of multiple diseases. This review summarizes how ATG7 is precisely programmed by genetic, transcriptional, and epigenetic modifications in cells and the relationship between ATG7 and aging-related diseases.

Role of non-coding RNAs and exosomal non-coding RNAs in retinoblastoma progression

Retinoblastoma (RB) is a rare aggressive intraocular malignancy of childhood that has the potential to affect vision, and can even be fatal in some children. While the tumor can be controlled efficiently at early stages, metastatic tumors lead to high mortality. Non-coding RNAs (ncRNAs) are implicated in a number of physiological cellular process, including differentiation, proliferation, migration, and invasion, The deregulation of ncRNAs is correlated with several diseases, particularly cancer. ncRNAs are categorized into two main groups based on their length, i.e. short and long ncRNAs. Moreover, ncRNA deregulation has been demonstrated to play a role in the pathogenesis and development of RB. Several ncRNAs, such as miR-491-3p, miR-613,and SUSD2 have been found to act as tumor suppressor genes in RB, but other ncRNAs, such as circ-E2F3, NEAT1, and TUG1 act as tumor promoter genes. Understanding the regulatory mechanisms of ncRNAs can provide new opportunities for RB therapy. In the present review, we discuss the functional roles of the most important ncRNAs in RB, their interaction with the genes responsible for RB initiation and progression, and possible future clinical applications as diagnostic and prognostic tools or as therapeutic targets.

Identification and analysis of microRNA editing events in recurrent bladder cancer based on RNA sequencing: MicroRNA editing level is a potential novel biomarker

Background: With the continued advancement of RNA-seq (RNA-sequencing), microRNA (miRNA) editing events have been demonstrated to play an important role in different malignancies. However, there is yet no description of the miRNA editing events in recurrent bladder cancer.

Objective: To identify and compare miRNA editing events in primary and recurrent bladder cancer, as well as to investigate the potential molecular mechanism and its impact on patient prognosis.

Methods: We examined the mRNA and miRNA transcriptomes of 12 recurrent bladder cancer cases and 13 primary bladder cancer cases. The differentially expressed mRNA sequences were analyzed. Furthermore, we identified the differentially expressed genes (DEGs) in recurrent bladder cancer. The Gene Ontology (GO) functional enrichment analyses on DEGs and gene set enrichment analysis were performed. The consensus molecular subtype (CMS) classification of bladder cancer was identified using the Consensus MIBC package in R (4.1.0); miRNA sequences were then further subjected to differentially expressed analysis and pathway enrichment analysis. MiRNA editing events were identified using miRge3.0. miRDB and TargetScanHuman were used to predict the downstream targets of specific differentially edited or expressed miRNAs. The expression levels of miR-154-5p and ADAR were validated by RT-qPCR. Finally, survival and co-expression studies were performed on the TCGA-BLCA cohort.

Results: First, the mRNA expression levels in recurrent bladder cancer changed significantly, supporting progression via related molecular signal pathways. Second, significantly altered miRNAs in recurrent bladder cancer were identified, with miR-154-5p showing the highest level of editing in recurrent bladder cancer and may up-regulate the expression levels of downstream targets HS3ST3A1, AQP9, MYLK, and RAB23. The survival analysis results of TCGA data revealed that highly expressed HS3ST3A1 and RAB23 exhibited poor prognosis. In addition, miR-154 editing events were found to be significant to CMS classification.

Conclusion: MiRNA editing in recurrent bladder cancer was detected and linked with poor patient prognosis, providing a reference for further uncovering the intricate molecular mechanism in recurrent bladder cancer. Therefore, inhibiting A-to-I editing of miRNA may be a viable target for bladder cancer treatment, allowing current treatment choices to be expanded and individualized.

LINC00488 Induces Tumorigenicity in Retinoblastoma by Regulating microRNA-30a-5p/EPHB2 Axis

OBJECTIVE

LINC00488 confers oncogenic activity in the progression of some tumors. Hence, the target of the study was about to specify LINC00488-mediated network in retinoblastoma (RB).

METHODS

LINC00488 expression was tested in RB clinical tissues. siRNA targeting LINC00488 or miR-30a-5p mimic was introduced into RB cell line (Y79) to observe cellular biological functions. The relationship between LINC00488, miR-30a-5p and EPHB2 was verified. Afterward, the role of miR-30a-5p involved in RB through targeted regulation of EPHB2 was probed in vitro and in vivo.

RESULTS

LINC00488 was induced in RB tissue and cells. LINC00488 knockdown or miR-30a-5p upregulation depressed the malignant activities of Y79 cells. LINC00488 could sponge miR-30a-5p that targeted EPHB2. EPHB2, and EPHB2 overexpression counteracted miR-30a-5p restoration-induced inhibition of Y79 cell development in vitro and in vivo.

CONCLUSION

LINC00488 induces tumorigenicity in RB by binding to miR-30a-5p to target EPHB2, which may offer a new clue of RB treatment from an lncRNA-miRNA-mRNA network.

Four Autophagy-Related Long Noncoding RNAs Provide Coexpression and ceRNA Mechanisms in Retinoblastoma through Bioinformatics and Experimental Evidence

Retinoblastoma (RB) is the most common type of intraocular malignant tumor that lowers the quality of life among children worldwide. Long noncoding RNAs (lncRNAs) are reported to play a dual role in tumorigenesis and development of RB. Autophagy is also reported to be involved in RB occurrence. Although several studies of autophagy-related lncRNAs in RB have been explored before, there are still unknown potential mechanisms in RB. In the present study, we mined dataset GSE110811 from the Gene Expression Omnibus database and downloaded autophagy-related genes from the Human Autophagy Database for further bioinformatic analysis. By implementing the differential expression analysis and Pearson correlation analysis on the lncRNA expression matrix and autophagy-related genes expression matrix, we identified four autophagy-related lncRNAs (namely, N4BP2L2-IT2, SH3BP5-AS1, CDKN2B-AS1, and LINC-PINT) associated with RB. We then performed differential expression analysis on microRNA (miRNA) from dataset GSE39105 for further analyses of lncRNA-miRNA-mRNA regulatory mechanisms. With the miRNA-lncRNA module on the StarBase 3.0 website, we predicted the differentially expressed miRNAs that could target the autophagy-related lncRNAs and constructed a potential lncRNA-miRNA-mRNA regulatory network. Furthermore, the functional annotations of these target genes in regulatory networks were presented using the Cytoscape and the Metascape annotation tool. Finally, the expression pattern of the four autophagy-related lncRNAs was evaluated via qRT-PCR. In conclusion, our findings suggest that the four autophagy-related lncRNAs could be critical molecules associated with the development of RB and affect the occurrence and development of RB through the lncRNA-miRNA-mRNA regulatory network. Genes (GRP13B, IFT88, EPHA3, GABARAPL1, and EIF4EBP1) may serve as potential novel therapeutic targets and biomarkers in RB.