OBJECTIVE: To investigate the expression of signal transducer and activator of transcription 3 (STAT3) and phosphorylated STAT3 (p-STAT3) protein in papillary thyroid carcinoma (PTC), and to explore the correlation and significance between the expression of STAT3, p-STAT3 and epithelial-mesenchymal transition (EMT). METHOD: The expression of STATS3. p-STAT3, E-cadherin and Vimentin protein in 56 cases of PTC specimens and adjacent normal tissues specimens ware detected by immunohistochemistry. The correlation of the expression of STATS, p-STAT3, E-cadherin and Vimentin protein in PTC with clinicopathological characteristics was analyzed. RESULT: The positive rates of STAT3, p-STAT3 in PTC tissue were significantly higher than those in adjacent normal tissues specimens respectively (P < 0.01). The positive rates of E-cadherin in PTC tissues were remarkably lower, compared to adjacent normal tissues specimens (P < 0.01), however the positive rates of Vimentin in PTC tissues were remarkably higher, compared to adjacent normal tissues specimens (P < 0.01). The expression of STAT3, p-STAT3, E-cadherin and Vimentin protein were associated with lymph node metastasis and clinical stage (all P < 0.05). The expression of STAT3 and p-STAT3 was negatively correlated with E-cadherin expression (r = -0.494 and r = -0.364, P < 0.01, respectively), but positively with Vimentin expression (r = 0.533 and r = 0.377, P < 0.01, respectively) in PTC tissues. CONCLUSION: PTC tissues have STAT3 protein activation and EMT phenotype, as were all correlated significantly with PTC invasion and metastasis. STAT3 signaling pathway activation might mediate EMT and then promote PTC invasion and metastasis.
OBJECTIVE: To investigate the expression of signal transducer and activator of transcription 3 (STAT3) and phosphorylated STAT3 (p-STAT3) protein in papillary thyroid carcinoma (PTC), and to explore the correlation and significance between the expression of STAT3, p-STAT3 and epithelial-mesenchymal transition (EMT). METHOD: The expression of STATS3. p-STAT3, E-cadherin and Vimentin protein in 56 cases of PTC specimens and adjacent normal tissues specimens ware detected by immunohistochemistry. The correlation of the expression of STATS, p-STAT3, E-cadherin and Vimentin protein in PTC with clinicopathological characteristics was analyzed. RESULT: The positive rates of STAT3, p-STAT3 in PTC tissue were significantly higher than those in adjacent normal tissues specimens respectively (P < 0.01). The positive rates of E-cadherin in PTC tissues were remarkably lower, compared to adjacent normal tissues specimens (P < 0.01), however the positive rates of Vimentin in PTC tissues were remarkably higher, compared to adjacent normal tissues specimens (P < 0.01). The expression of STAT3, p-STAT3, E-cadherin and Vimentin protein were associated with lymph node metastasis and clinical stage (all P < 0.05). The expression of STAT3 and p-STAT3 was negatively correlated with E-cadherin expression (r = -0.494 and r = -0.364, P < 0.01, respectively), but positively with Vimentin expression (r = 0.533 and r = 0.377, P < 0.01, respectively) in PTC tissues. CONCLUSION: PTC tissues have STAT3 protein activation and EMT phenotype, as were all correlated significantly with PTC invasion and metastasis. STAT3 signaling pathway activation might mediate EMT and then promote PTC invasion and metastasis.