If a colon cancer cell line develops a mutation that constitutively activates EGFR (epidermal growth factor receptor), which consequence involving cell cycle regulation is most likely?

💡 Explanation

Constitutive EGFR activation drives continuous cell division signals, overriding normal checkpoint controls. This is because EGFR signaling promotes cyclin D expression, thus cells bypass the G1/S checkpoint. Therefore, the checkpoint is circumvented, rather than DNA repair being enhanced or cells becoming sensitive to apoptosis.

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