Circulating Proteasomes in the Pathogenesis of Head and Neck Squamous Cell Carcinoma.

Increased proteasome activity was revealed in blood serum of patients with stage T1N0M0 head and neck squamous cell carcinoma in comparison with patients with chronic diseases of the larynx and laryngopharynx. This opens prospects of using chymotrypsin-like activity measurement for differential diagnosis of squamous cell carcinoma, screening for high-risk groups, and evaluation of the degree of tumor differentiation.