Chromosomally unstable tumor cells specifically require KIF18A for proliferation

Area of Science:

• Oncology
• Cell Biology
• Biochemistry

Background:

• Chromosomal instability (CIN) is a key feature of cancer cells, arising from errors in mitotic spindle regulation.
• CIN cells exhibit altered microtubule dynamics, potentially making them vulnerable to specific therapeutic interventions targeting the mitotic spindle.

Purpose of the Study:

• To investigate the differential response of CIN tumor cells versus near-diploid cells to the inhibition of kinesin motor proteins involved in mitotic spindle control.
• To identify specific kinesin targets that selectively impact CIN cell proliferation.

Main Methods:

• Inhibition of KIF18A, a kinesin motor protein, in CIN cells derived from triple-negative breast cancer and colorectal cancer.
• Comparison of cellular responses (mitotic delays, spindle morphology, cell death) between CIN and near-diploid cells following KIF18A inhibition.
• Correlation analysis between KIF18A sensitivity and centrosome fragmentation.

Main Results:

• KIF18A is essential for the proliferation of CIN cells but not near-diploid cells.
• KIF18A inhibition in CIN cells leads to mitotic delays, multipolar spindles, and increased cell death.
• Sensitivity to KIF18A knockdown correlates with centrosome fragmentation in CIN cells.

Conclusions:

• Altered microtubule dynamics in CIN tumor cells can be exploited therapeutically.
• KIF18A inhibition represents a potential strategy to reduce the proliferative capacity of CIN cells.
• Targeting KIF18A may offer a selective approach for treating cancers characterized by chromosomal instability.