Finally, in breast cancer patients, nuclear CtsL has been shown to interact with the Cyclin-Dependent Kinase 2-associated Protein 1 (CDK2AP1), an inhibitor of CDK2, thus revealing a potential role for CtsL as a regulator of cell cycle in breast cancer cells, contributing to aberrant cancer cell proliferation [259]. This evidence concerns the gene CDK2AP1 and breast carcinoma.