MicroRNA-377-3p promotes cell proliferation and inhibits cell cycle arrest and cell apoptosis in hepatocellular carcinoma by affecting EGR1-mediated p53 activation

Cyclin B2 impairs the p53 signaling in nasopharyngeal carcinoma

BACKGROUND

Cyclin B2 (CCNB2), a member of the cyclin family, is an oncogene in multiple cancers, including nasopharyngeal carcinoma (NPC). However, the epigenetics mechanism for CCNB2 overexpression in NPC remains unclear. This study dissects the regulatory role of CCNB2 in NPC and the molecular mechanism.

METHODS

Differentially methylated genes (DMG) and differentially expressed genes (DEG) were screened out in GSE52068 and GSE13597 databases, respectively, and candidate targets were identified by the Venn diagram. GO annotation and pathway enrichment analyses were performed on selected DMG and DEG, and a PPI network was constructed to pinpoint hub genes. PCR and qMSP were conducted to detect the expression and methylation of CCNB2 in cells. The siRNA targeting CCNB2 was transfected into NPC cells, and the migration, proliferation, cell cycle, epithelial-mesenchymal transition (EMT), tumorigenesis, and metastasis were examined. The upstream factor responsible for CCNB2 overexpression in NPC was explored. The p53 activity in NPC cells was assessed using western blot analysis.

RESULTS

CCNB2 showed hypomethylation and overexpression in NPC. CCNB2 silencing inhibited cell migration, proliferation, cell cycle entry, and EMT. JMJD6 was overexpressed in NPC and upregulated CCNB2 through demethylation. JMJD6 reversed the effects of CCNB2 downregulation, resulting in elevated cellular activity in vitro and tumorigenic and metastatic activities in vivo. CCNB2 blocked the p53 pathway, while the p53 pathway inhibitor reversed the effect of CCNB2 silencing to increase the activity of NPC cells.

CONCLUSIONS

JMJD6 enhanced CCNB2 transcription by demethylating CCNB2, thereby repressing the p53 pathway and promoting NPC progression.

MiRNAs in Alcohol-Related Liver Diseases and Hepatocellular Carcinoma: A Step toward New Therapeutic Approaches?

Alcohol-related Liver Disease (ALD) is the primary cause of chronic liver disorders and hepatocellular carcinoma (HCC) development in developed countries and thus represents a major public health concern. Unfortunately, few therapeutic options are available for ALD and HCC, except liver transplantation or tumor resection for HCC. Deciphering the molecular mechanisms underlying the development of these diseases is therefore of major importance to identify early biomarkers and to design efficient therapeutic options. Increasing evidence indicate that epigenetic alterations play a central role in the development of ALD and HCC. Among them, microRNA importantly contribute to the development of this disease by controlling the expression of several genes involved in hepatic metabolism, inflammation, fibrosis, and carcinogenesis at the post-transcriptional level. In this review, we discuss the current knowledge about miRNAs' functions in the different stages of ALD and their role in the progression toward carcinogenesis. We highlight that each stage of ALD is associated with deregulated miRNAs involved in hepatic carcinogenesis, and thus represent HCC-priming miRNAs. By using in silico approaches, we have uncovered new miRNAs potentially involved in HCC. Finally, we discuss the therapeutic potential of targeting miRNAs for the treatment of these diseases.

Comprehensive analysis of potential ceRNA network and immune cell infiltration in intervertebral disc degeneration

Background

Intervertebral disc degeneration (IDD) has become a serious public health problem, the mechanism of which is complex and still unclear. We aimed to construct a ceRNA network related to IDD to explore its pathogenesis.

Methods

We downloaded the GSE67566, GSE63492, GSE116726 and GSE124272 datasets from GEO database, and obtained the differentially expressed RNAs. Then, we constructed a ceRNA network and the KEGG and GO enrichment analysis were performed. Finally, we performed immune cell infiltration analysis on the GSE124272 dataset and analysed the correlation between immune cell abundance and hub genes expression levels.

Results

The ceRNA network included three down-regulated circRNAs: hsa_circ_0074817, hsa_circ_0002702, hsa_circ_0003600, three up-regulated miRNAs: hsa-miR-4741, hsa-miR-3158-5p, hsa-miR-508-5p, and 57 down-regulated mRNAs, including six hub genes: IGF1, CHEK1, CCNB1, OIP5, BIRC5, AR. GO and KEGG analysis revealed that the network is involved in various biological functions. Immune infiltration analysis showed that IDD was closely related to immune cell infiltration, and hub genes could further affect the development of IDD by affecting immune cell infiltration.

Conclusion

This study identified the hsa_circ_0074817-hsa-miR-508-5p-IGF1/CHEK1/CCNB1, the hsa_circ_0003600-hsa-miR-4741-BIRC5/OIP5/AR and the hsa_circ_0002702-hsa-miR-3158-5p-IGF1/AR as important regulatory axis of IDD, which will help us gain further insight into the pathogenesis of IDD and determine potential therapeutic targets.