Final answer:
Collagenase is the enzyme that helps cancer cells penetrate the extracellular matrix by digesting it.
Step-by-step explanation:
The enzyme that helps cancer cells penetrate the extracellular matrix by digesting it is called collagenase.
Collagenase is produced by both cancer cells and the cells surrounding a tumor. It digests collagen, which is a protein found in the extracellular matrix.
By degrading collagen, collagenase allows cancer cells to break through the extracellular matrix and invade nearby tissues.