RHOV Is a Detachment-Responsive Rho GTPase Necessary for Ovarian Cancer Peritoneal Metastasis

Area of Science:

• Oncology
• Molecular Biology
• Cell Biology

Background:

• Epithelial ovarian cancer predominantly spreads via transcoelomic metastasis, a process driven by tumor cells in peritoneal fluid.
• This metastatic progression is the primary cause of mortality in ovarian cancer patients.
• Understanding early cellular adaptations to matrix detachment is key to preventing metastasis.

Purpose of the Study:

• To identify early molecular adaptations enabling ovarian cancer cells to survive matrix detachment.
• To investigate the role of the Rho GTPase RHOV in ovarian cancer metastasis.

Main Methods:

• Analysis of a conserved detachment-sensitive gene signature in ascites-derived ovarian cancer cell lines.
• Functional studies involving RHOV knockdown and rescue experiments in vitro and in vivo.
• Investigation of RHOV's downstream signaling pathways, including c-Jun signaling and cytoskeletal remodeling.

Main Results:

• A gene signature activated by matrix detachment was identified, with RHOV being highly induced.
• Loss of RHOV impaired anoikis resistance, multicellular aggregate formation, migration, and invasion.
• RHOV deficiency completely abolished metastasis in vivo, while its function required GTP-binding and membrane localization.
• RHOV was found to enhance c-Jun signaling and cytoskeletal remodeling.

Conclusions:

• RHOV is a critical, detachment-sensitive Rho GTPase essential for ovarian cancer peritoneal metastasis.
• Targeting RHOV and early post-detachment adaptations presents a potential therapeutic strategy for metastatic ovarian cancer.
• This study elucidates RHOV's pro-metastatic functions and its role in understudied Rho GTPase family members.