The Application Value Of Thymidine Kinase1in Esophageal Squamous Cell Carcinoma Diagnosis

Background： Esophageal cancer, with obvious characteristics of regionaldistribution,is one of the most common malignancies of digestive tract throughout theworld. The incidence and mortality of Esophageal cancer in China ranks first in theworld, Henan and some other provinces undergo high incidence of esophageal cancer[1].Esophageal squamous cell carcinoma accounts for90%of esophageal cancer in China[2], which has a higher invasive and different biological characteristics fromadenocarcinoma. The esophageal squamous cell carcinoma is treated by comprehensiveapproach consisted of operation,radiotherapy and chemotherapy.Although thetreatments have progressed, the long-term prognosis of patients is still not satisfied,because of the poor early diagnosis rate. Studies show that early diagnosis andtreatment of most tumor will improve the survival rate of patients.Thymidine kinase1(TK1),a kind of enzymes,is closely related to synthesis and repairof DNA. The level of TK1in proliferating cells is significantly higher than that innon-proliferating cells. To a certain extent,the content of serological thymidine kinase1(STK1) responses to the cell proliferation in the body. In patients with malignanttumors, more than95%of the STK1activity is derived from malignant cells[3].Therefore, STK1is a good biomarker indicating the multiplication of tumor cells.As themonoclonal and polyclonal antibody of human TK1have been developed, TK1protein level in serum which is extremely low can be tested base on the sensitiveenhanced chemiluminescence and dot blot assay. STK1has been widely used in variousclinical solid tumors and hematological system tumor as a serum tumor marker in earlydiagnosis, prognosis and treatment response. Objective：To investigate the level and clinical significance of serum TK1inpatients with esophageal squamous cell carcinoma.Methods:1.100samples collected from esophageal squamous cell carcinoma patientsand60samples from healthy adults were measured for the level of serum TK1byenzyme immunoassay and ot blot enhanced chemiluminescence assay.2.Then comparedthe random40patients’serum TK1before and after operation.3.Finally,analysed thecorrelation between the level of serum TK1from100esophageal squamous cellcarcinoma patients and gender,age, smoking history, family history of cancer,the TNMstages, lymph node metastasis,as well as the degree of tumor differentiation.Results:1.The positive rate （P<0.01）and the level of TK1（P<0.001） in esophagealsquamous cell carcinoma group were significantly higher than that in healthy group.2.The positive rate （P<0.01）and the value of TK1（P<0.001）in pre-operation groupwere both decreased than the post operation group.3.While the TK1value of Ⅲ+Ⅳstages and lymph node metastasis ones were also higher than that ofⅠ+Ⅱstages（P<0.05）and lymph node metastasis-free one（sP<0.05）,respectively. The higher thedegree of differentiation, the lower the STK1value is (P <0.01). The S-TK1concentration is unrelated with gender, age, smoking history or family history of cancer.Conclusion:Serum TK1testing shows critical clinical significance indiagnosis,treatment and prognostic of esophageal squamous cell carcinoma patients.