E2F3 gene expression is a potential negative prognostic marker for localised and MYCN not-amplified neuroblastoma: Results of in silico analysis of 786 samples

Overexpression of H2AFX gene in neuroblastoma is associated with worse prognosis

BACKGROUND

Neuroblastoma (NB) is the most common solid tumour in childhood, and rises in the sympathetic nervous system. Here, we addressed the in silico analysis of the association between the expression of H2AFX gene involved in DNA damage response, and the survival of a cohort of 786 NB patients.

METHODS

In silico gene expression was retrieved from the publicly available dataset summarised by Cangelosi et al., including 13,696 gene expression profiles of 786 NB tumours at onset of disease. The prognostic value of H2AFX (H2A histone family member X) gene expression for event-free survival (EFS) and overall survival (OS) was evaluated by Kaplan-Meier and Cox regression analysis. The main results were validated on another openly accessible in silico database (NRC-283) containing 13,489 gene expressions in 283 NB patients. The expression of H2AFX protein was then tested by immunofluorescence on 48 primary NB samples of different tumour stages. H2AFX activity as an oncogene has been further validated in vitro by silencing the molecule in two NB cell lines, characterised by MYCN amplified or not, and performing cell growth and migration assays.

RESULTS

A strong inverse association between H2AFX expression and patients' survival was observed and confirmed by immunofluorescence results on primary NB tissue sections. Cox regression analysis also disclosed H2AFX as an independent predictor of EFS and OS. The gene-silencing experiments strongly suggested an oncogenic role for H2AFX on NB cells, regardless of MYCN amplification.

CONCLUSIONS

H2AFX is a prognostic marker for unfavourable NB and could be considered a target for therapeutic interventions.

Circ_0001495 influences the development of endometriosis through the miRNA-34c-5p/E2F3 axis

Endometriosis is a chronic gynecological condition characterized by the presence of endometrial glands and stroma outside the uterine cavity., accounting for 7% of all female malignant tumors and 20%- 30% of malignant tumors of the female reproductive system. Multiple studies have shown that circular RNA (circRNA) has the potential to become a targeted target and marker for EM. However, the roles of circ_0001495 in EM are still unclear. Our research aims to reveal the molecular mechanism of circ_0001495 in EM. In this study, RT-PCR or western blot were conducted to determine mRNA and protein expression. cell viability, proliferation, migration, invasion, and apoptosis were assessed by CCK-8, EdU, wound healing, transwell, and flow cytometry analyses, respectively. Additionally, the targeting relationship between miR-34c-5p and circ_0001495 or E2F3 was confirmed through dual-luciferase reporter gene assay. We found significant overexpression of circ_0001495 in EM tissues and cells. Knockdown of circ_0001495 inhibited the proliferation, migration and invasion of ectopic endometrial stromal cells (EESCs) and increased cell apoptosis. Moreover, we found that circ_0001495 regulated E2F3 levels by interacting with miR-34c-5p in EESC. Furthermore, in vitro, miR-34c-5p inhibition or E2F3 overexpression could attenuate the effect of circ_0001495 silencing on EM progression. In addition, the vivo experiment demonstrated that inhibition of circ_0001495 could repress the development of endometriosis by regulating the miR-34c-5p/E2F3 axis. In conclusion, our study suggested that circ_0001495 promoted EM progression in vitro and in vivo through the miR-34c-5p/E2F3 axis, which might be a potential therapeutic target for EM.