Cell Cycle-Dependent Tumor Engraftment and Migration Are Enabled by Aurora-A

Area of Science:

• Molecular Biology
• Cell Biology
• Cancer Research

Background:

• Cell-cycle progression and cell migration are key features of human carcinoma.
• These processes are often considered independent but may share regulatory pathways involving microtubule nucleation at centrosomes.

Purpose of the Study:

• To investigate the molecular mechanisms connecting cell-cycle progression and cell migration in breast cancer.
• To identify key proteins and pathways involved in regulating these interconnected processes.

Main Methods:

• Utilized multiparameter imaging of wound closure assays in 4T1-luciferase2 breast cancer cells.
• Tracked cell-cycle progression, cell migration, and microtubule nucleation dynamics.
• Employed gene silencing (HMMR) and pharmacological inhibition (Aurora kinase-A) to study pathway components.

Main Results:

• Cell migration velocity and directionality were elevated during the S-G2 phases of the cell cycle, associated with front-polarized centrosomes and increased microtubule nucleation.
• Inhibition of Aurora kinase-A (AURKA) reduced migratory phenotypes without affecting cell-cycle progression.
• The Aurora-A/TPX2/HMMR axis was identified as a key regulator, with HMMR-T703 phosphorylation predicting survival in ER-negative breast cancer patients.

Conclusions:

• Demonstrated a molecular axis (Aurora-A/TPX2/HMMR) that intersects cell-cycle progression and cell migration.
• This pathway regulates microtubule cytoskeleton dynamics, influencing tumor cell engraftment and migration.
• The Aurora-A/TPX2/HMMR axis represents a potential therapeutic target for improving survival in ER-negative breast tumors.