Objective: To explore clinical evaluate of CK19 mRNA and EGFR mRNA for diagnosis of laryngeal carcinoma micrometastasis, correlation between circulation tumor cell and lymph node metastasis.
Method: Of 30 nude mice, 25 were randomly divided into 5 experimental groups (5 mice in each group), 5 were acted as control group. The mice were killed 2,4,6,8 and 10 weeks after injection. The expression of CK19 and EGFR mRNA in the peripheral blood and tumor tissue were detected by RT-PCR assay. The expression of EGFR in tumor tissue were detected by immunohistochemistry and lymph node transfer were confirmed using continuous pathological dying.
Result: None of CK19 and EGFR mRNA were detected in peripheral blood of control group, CK19 mRNA-positive rate was 48% and 80% in peripheral blood and tumor tissue from the experimental group, respectively, and EGFR mRNA-positive rate was 36% and 76%, respectively. Lymph node metastasis happened in the exponential growth phase and transfer rate was 60%(15/25). The expression of CK19 mRNA and EGFR mRNA in lymphatic metastasis groups was higher than that of control, with a positive correlation between lymphatic metastasis and CTC (r = 0.655 , P < 0.01). The protein positive expression rate of EGFR were 88%(22/25) in tumor tissue. All peripheral blood expressed EGFR concomitant EGFR expressing in tumor tissues, and a high expression of EGFR in tumor tissue displayed high expression of EGFR in peripheral blood as well.
Conclusion: The expression of CK19 and EGFR mRNA in the peripheral blood can provide predictive information of lymphatic metastasis, EGFR mRNA might be a new target of treatment and diagnosis for malignant tumour.