HuR (ELAVL1) Stabilizes SOX9 mRNA and Promotes Migration and Invasion in Breast Cancer Cells

Area of Science:

• Oncology
• Molecular Biology
• Gene Regulation

Background:

• RNA-binding proteins (RBPs) regulate gene expression and are implicated in cancer progression.
• HuR (Human antigen R) is an RBP that stabilizes mRNAs with AU-rich elements (AREs).
• The specific mRNA targets and functions of HuR in triple-negative breast cancer (TNBC) are not fully understood.

Purpose of the Study:

• To identify novel HuR-regulated mRNA targets in TNBC.
• To investigate the functional role of HuR-SOX9 interaction in TNBC cell behavior.

Main Methods:

• Bioinformatic analysis of gene expression profiles in HuR-silenced TNBC cells (Hs578T).
• Ribonucleoprotein immunoprecipitation (RIP) assays to confirm HuR-mRNA interaction.
• Assessment of SOX9 mRNA and protein levels, cell migration, and invasion assays.

Main Results:

• SOX9 was identified as a potential HuR target gene.
• Direct binding of HuR to SOX9 mRNA was confirmed via RIP assays.
• HuR depletion led to decreased SOX9 mRNA half-life and protein levels.
• Silencing HuR reduced migration and invasion in TNBC cells, mimicking SOX9 silencing effects.

Conclusions:

• HuR directly regulates SOX9 mRNA stability and protein expression in TNBC.
• The HuR-SOX9 axis plays a role in promoting migration and invasion in TNBC.
• Targeting HuR may offer a therapeutic strategy for inhibiting TNBC metastasis.