TK-1 Recombinant Rabbit mAb (SDT-4127-9)

Human thymidine kinase 1 (TK1) is a cell-cycle-dependent enzyme that catalyzes the phosphorylation of thymidine, a key step in DNA precursor synthesis. Its expression is tightly restricted to the S phase of proliferating cells, making it a sensitive biomarker reflecting cellular proliferation activity. Serum TK1 concentration is barely detectable in quiescent normal cells but rises markedly when cells undergo malignant transformation and rapid division.

Serum TK1 measurement serves as a valuable auxiliary tumor marker for early screening, risk stratification and therapeutic monitoring of multiple malignancies, including lung, breast, colorectal and hematological cancers. Pre-treatment TK1 levels correlate with tumor burden, differentiation grade and metastatic potential. A sustained decrease in TK1 after surgery, chemotherapy or targeted therapy indicates effective tumor control, while persistent elevation suggests residual tumor cells or high recurrence risk. Compared with conventional tumor markers, TK1 mirrors proliferation status rather than tissue origin, enabling dynamic assessment of disease progression.

However, TK1 lacks absolute tumor specificity. Benign proliferative disorders, inflammation and tissue injury can also trigger mild TK1 elevation, which may lead to false-positive results. Therefore, TK1 cannot independently confirm cancer diagnosis and must be interpreted together with imaging findings, pathological results and other tumor biomarkers. Collectively, human TK1 detection provides critical quantitative information on tumor proliferation, assisting clinicians in evaluating disease aggressiveness, predicting prognosis and monitoring treatment response in oncology practice.