TROP2 Promotes Tumor Cell Migration through Downregulation of DSG2 Revealed by Super-Resolution Fluorescence Imaging

Area of Science:

• Oncology
• Cell Biology
• Molecular Mechanisms

Background:

• TROP2 is a significant biomarker and therapeutic target in epithelial cancers, linked to tumor proliferation, invasion, and metastasis.
• Tumor cell migration is crucial for invasiveness, malignancy, and patient prognosis, yet TROP2's role in this process is not fully understood.
• Desmosomes are vital for tissue architecture, but their alteration in cancer and relation to TROP2 requires further study.

Purpose of the Study:

• To elucidate the molecular mechanism by which TROP2 regulates tumor cell migration.
• To investigate the role of desmosomal cadherin DSG2 in TROP2-mediated tumor cell migration.
• To understand how TROP2 affects desmosome assembly and downstream signaling pathways.

Main Methods:

• Direct stochastic optical reconstruction microscopy (dSTORM) and biochemical assays.
• Co-localization imaging and co-immunoprecipitation to confirm TROP2-DSG2 interaction.
• TROP2 overexpression and knockdown cell lines, with validation at the tissue level.

Main Results:

• TROP2 interacts with DSG2, downregulating its levels and impairing desmosome assembly.
• High TROP2 expression promotes tumor cell proliferation and migration.
• TROP2 activates EGFR/AKT and FAK signaling pathways by suppressing DSG2.

Conclusions:

• TROP2 promotes tumor cell migration by downregulating DSG2 and disrupting desmosome integrity.
• The study reveals a novel mechanism linking TROP2, DSG2, and cell migration in epithelial cancers.
• Findings provide a basis for targeted therapies against TROP2 and its signaling pathways in cancer treatment.