FCHSD2 controls oncogenic ERK1/2 signaling outcome by regulating endocytic trafficking

Area of Science:

• Oncology
• Cell Biology
• Molecular Biology

Background:

• Receptor tyrosine kinases (RTKs) drive cancer metastasis through altered intracellular signaling.
• Clathrin-mediated endocytosis (CME), recycling, and degradation regulate RTK surface levels and activity.
• Oncogenic signaling can create feedback loops to enhance tumor progression by regulating endocytic trafficking.

Purpose of the Study:

• To investigate the role of FCH/F-BAR and Double SH3 Domain-Containing Protein (FCHSD2) in non-small-cell lung cancer (NSCLC) progression.
• To elucidate the impact of FCHSD2 loss on RTK trafficking and downstream signaling.
• To explore the clinical relevance of FCHSD2 and Ras-related protein Rab-7A (Rab7) in NSCLC patient outcomes.

Main Methods:

• Investigated FCHSD2 function in NSCLC cells.
• Analyzed the trafficking of epidermal growth factor receptor (EGFR) and c-Met (MET) upon FCHSD2 depletion.
• Assessed the nuclear translocation of extracellular signal-regulated kinase 1 and 2 (ERK1/2).
• Correlated FCHSD2 and Rab7 expression with NSCLC tumor grades and patient survival data.

Main Results:

• FCHSD2 loss impairs EGFR and MET recycling, directing them to late endosomes and lysosomal degradation.
• FCHSD2 depletion causes nuclear translocation of active ERK1/2, up-regulating EGFR and MET.
• Ras-related protein Rab-7A (Rab7) is critical for FCHSD2 depletion-induced effects.
• FCHSD2 loss correlates with higher NSCLC tumor grades.
• High FCHSD2 expression is linked to better patient survival, while high Rab7 expression is associated with decreased survival.

Conclusions:

• FCHSD2 plays a crucial role in regulating RTK trafficking and signaling in NSCLC.
• The FCHSD2-Rab7 axis influences oncogenic signaling and RTK homeostasis, impacting cancer progression.
• FCHSD2 and Rab7 serve as potential prognostic biomarkers for NSCLC.