Eps8 controls Src- and FAK-dependent phenotypes in squamous carcinoma cells

Area of Science:

• Cell Biology
• Cancer Research
• Molecular Biology

Background:

• Eps8 is an actin regulatory protein with elevated expression in squamous cell carcinoma (SCC).
• Eps8 interacts with focal adhesion kinase (FAK) and Src in SCC cells, particularly in the DMBA/TPA chemical carcinogenesis model.

Purpose of the Study:

• To elucidate novel roles of Eps8 in regulating the spatial distribution and function of Src and FAK in SCC.
• To understand how Eps8 modulates SCC cell invasion and migration through its interactions with FAK and Src.

Main Methods:

• Investigated Eps8's role in controlling active Src localization in SCC cells.
• Examined the FAK-dependent and FAK-absent mechanisms of Src trafficking mediated by Eps8.
• Assessed the requirement of Eps8 for FAK-dependent SCC cell polarization and invasion.

Main Results:

• Eps8 controls active Src spatial distribution in a FAK-dependent manner.
• In FAK-absent SCC cells, Eps8 drives Src trafficking to autophagic structures.
• In FAK-expressing SCC cells, Eps8 localizes to focal adhesions and is essential for FAK-dependent polarization and invasion.

Conclusions:

• Eps8 is a critical mediator of Src and FAK functions in SCC.
• Eps8 regulates actin rearrangements, influencing Src localization and modulating FAK/Src-driven invasive migration.
• Eps8 plays a dual role in SCC cell behavior, affecting both autophagic coping mechanisms and invasive processes.