EphA3 targeted by miR-3666 contributes to melanoma malignancy via activating ERK1/2 and p38 MAPK pathways

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• Melanoma is a rare but fatal skin cancer.
• The precise role of EPH receptor A3 (EphA3) in melanoma remains unclear despite its observed deregulation.

Purpose of the Study:

• To investigate the functional role of EphA3 in melanoma.
• To elucidate the regulatory relationship between miR-3666 and EphA3.
• To determine the downstream signaling pathways involved in EphA3-mediated melanoma progression.

Main Methods:

• Real-time quantitative PCR and Western blotting to assess gene and protein expression.
• Cell Counting Kit-8, scratch wound, and in vivo assays to evaluate cell proliferation, migration, and tumor growth.
• Luciferase reporter assays to confirm direct targeting of EphA3 by miR-3666.
• Analysis of p38-MAPK and ERK1/2 signaling pathway activation.

Main Results:

• EphA3 expression was upregulated in melanoma tissues and cells, inversely correlated with miR-3666 levels.
• Silencing EphA3 inhibited melanoma cell proliferation and migration, and reduced tumor growth in vivo.
• miR-3666 directly targets the 3'UTR of EphA3.
• miR-3666 mimic suppressed EphA3-driven melanoma cell proliferation and migration, and inactivated p38-MAPK and ERK1/2 pathways.

Conclusions:

• miR-3666 suppresses melanoma malignancy by downregulating EphA3 expression.
• The miR-3666/EphA3 axis inactivates the ERK1/2 and p38 MAPK pathways, inhibiting melanoma progression.
• The miR-3666/EphA3 interaction represents a potential therapeutic target for melanoma treatment.