SPRED2 suppresses the stemness of hepatocellular carcinoma through the p53/miR-506-3p/KLF4 pathway

Area of Science:

• Oncology
• Molecular Biology
• Gene Regulation

Background:

• Endogenous Sprouty-related, EVH1 domain-containing protein 2 (SPRED2) inhibits the Ras/Raf/ERK-MAPK pathway.
• SPRED2 controls hepatocellular carcinoma (HCC) cell stemness by downregulating pluripotency factors like KLF4.
• The precise mechanisms of SPRED2's regulation of HCC stemness were previously unclear.

Purpose of the Study:

• To elucidate the molecular mechanisms by which SPRED2 regulates HCC cell stemness.
• To identify the key pluripotency factors and regulatory pathways involved in SPRED2's function.
• To validate the findings in clinical HCC samples.

Main Methods:

• Utilized human HCC cell lines (HepG2, HLE, Hep3B) with SPRED2 manipulation (deficiency/overexpression).
• Employed Western blot, RT-qPCR, co-immunoprecipitation, and ChIP-qPCR to assess protein/mRNA levels and interactions.
• Analyzed protein-protein interactions and gene transcription activation.
• Validated findings using clinical HCC tissues.

Main Results:

• KLF4 was identified as the primary pluripotency factor mediating SPRED2's stemness-suppressive effect.
• SPRED2 forms a complex with p53, enhancing transcription of miR-506-3p.
• Increased miR-506-3p directly downregulates KLF4 mRNA expression.
• Clinical HCC samples showed a negative correlation between KLF4 and miR-506-3p, and a positive correlation between miR-506-3p and SPRED2.

Conclusions:

• A novel SPRED2/p53/miR-506-3p/KLF4 axis was discovered, mediating SPRED2's suppression of HCC cell stemness.
• This axis represents a potential therapeutic target for preventing HCC progression.
• SPRED2 plays a critical role in regulating HCC cell stemness through this newly identified pathway.