TRPV4 Regulates Breast Cancer Cell Extravasation, Stiffness and Actin Cortex

Area of Science:

• Oncology
• Molecular Biology
• Cell Biology

Background:

• Metastasis significantly impacts patient survival, with current treatments showing limited efficacy.
• Identifying novel molecular targets is crucial for improving outcomes in metastatic diseases.
• Understanding the genetic underpinnings of metastasis aids in developing targeted therapies.

Purpose of the Study:

• To investigate the molecular mechanisms driving cancer metastasis.
• To identify potential therapeutic targets for metastatic cancers.
• To explore the role of Transient Receptor Potential Vanilloid subtype 4 (TRPV4) in metastasis.

Main Methods:

• Utilized phosphoproteomics on an in vitro model of isogenic cell lines with varying metastatic potential.
• Analyzed TRPV4 mRNA levels in human epithelial cancers (breast, gastric, ovarian).
• Performed gene knockdown experiments in mouse xenografts and assessed cell behavior (invasion, migration, softness, blebbing).

Main Results:

• Phosphoproteomics implicated TRPV4 in breast cancer metastasis.
• Elevated TRPV4 mRNA levels correlated with poor clinical outcomes in breast, gastric, and ovarian cancers.
• TRPV4 knockdown reduced metastatic nodules in vivo and impaired cancer cell invasion and transendothelial migration, without affecting proliferation.
• TRPV4 overexpression increased cancer cell softness and altered actin organization.

Conclusions:

• TRPV4 plays a critical role in cancer cell extravasation, potentially by modulating cell rigidity via cytoskeletal control.
• TRPV4 represents a promising therapeutic target for improving treatment strategies against metastatic epithelial cancers.
• These findings offer new insights into the molecular drivers of cancer metastasis.