Recently, serum HMGB-1, SIL-2R, TgAb and other markers have been gradually applied in diagnosing thyroid cancer, of which HMGB-1 is a highly conserved DNA marker capable of mediating tumor initiation and progression, which is highly expressed in malignant tumors but has a certain false negative rate, so it is often used as a secondary indicator in combination with SIL-2R, one of the immunosuppressive agents that can attenuate the endocrine effects in body, reduce the immune system capacity, thus promoting tumor cell differentiation and proliferation. The gene discussed is HMGB1; the disease is thyroid cancer.