Long Noncoding RNA MEG3 Interacts with p53 Protein and Regulates Partial p53 Target Genes in Hepatoma Cells

Area of Science:

• Molecular Biology
• Oncology
• Genetics

Background:

• Maternally Expressed Gene 3 (MEG3) is a long noncoding RNA (lncRNA) implicated in tumor suppression.
• The precise mechanisms of MEG3's function, particularly its interaction with p53, require further elucidation in human diseases like hepatocellular carcinoma (HCC).

Purpose of the Study:

• To investigate the functional relationship between MEG3 and p53 in hepatoma cells.
• To determine the role of MEG3 in regulating p53 activity and its impact on HCC progression.

Main Methods:

• Transfection of MEG3 expression constructs into hepatoma cells.
• Deletion analysis of MEG3 to identify critical functional domains.
• Co-immunoprecipitation and qRT-PCR to assess protein interactions and gene expression.
• Cell proliferation and apoptosis assays.

Main Results:

• MEG3 enhances the stability and transcriptional activity of p53.
• The full-length MEG3 structure is essential for p53 activation.
• MEG3 directly interacts with the p53 DNA binding domain, leading to deregulation of p53 target genes.
• MEG3 expression is frequently reduced or lost in HCC samples.
• Overexpression of MEG3 inhibits hepatoma cell proliferation and induces apoptosis.

Conclusions:

• MEG3 functions as a tumor suppressor in hepatoma cells.
• MEG3 activates p53-mediated transcription by interacting with p53, thereby influencing target gene expression.
• MEG3 represents a potential therapeutic target for hepatocellular carcinoma.