EGCG regulates TGF-β1-induced epithelial mesenchymal transition in squamous cell carcinoma of head and neck / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To study the effect and molecular mechanism of epigallocatechin-3-gallate (EGCG) on epithelial-mesenchymal transition (EMT) in vitro induced by human recombinant TGF-β1 protein in squamous cell carcinoma of the head and neck.</p><p><b>METHODS</b>EMT morphological changes of Tu686 cells were observed after sequential treatment of 5 ng/ml TGF-β1 and 20 µmol/L EGCG. Tu686 cells were collected after the treatment of 5 ng/ml TGF-β1 for 24 h and EGCG with different concentrations (0, 10, 20, 30 µmol/L) for another 24 h or 20 µmol/L EGCG treatment for different time phase (6, 12, 24 h). Then RT-PCR and Western-blot were applied to detect mRNA and protein expression level of epithelial cell marker E-cadherin, mesenchymal cell marker Vimentin and Smad7, an inhibit molecule of TGF-β1 mediated pathway in Tu686 cells.</p><p><b>RESULTS</b>TGF-β1 successfully induced characterized EMT morphological and molecular changes in Tu686 cells, in which expression of E-cadherin decreased, Vimentin increased and Smad7 declined. However, EGCG could reverse the TGF-β1 mediated process of EMT by downregulating the expression of Vimentin and upregulating the expression of E-cadherin and Smad7.</p><p><b>CONCLUSION</b>EGCG significantly inhibits TGF-β1-mediated EMT inTu686 cell lines of SCCHN, which maybe associated with the upregulated-expression of Smad7, an inhibitor in TGF-β1 signaling pathway.</p>

Correlation of EphA2 protein expression with clinicopathological characteristics and prognosis in laryngeal squamous cell carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the expression of EphA2 protein in tissue specimens and cell lines of laryngeal squamous cell carcinoma (LSCC), and to further study the correlation of EphA2 protein expression with clinicopathological characteristics and prognosis in LSCC.</p><p><b>METHODS</b>Western blot was applied to assess the EphA2 protein expression in LSCC cell line Hep-2 cells and the head and neck immortalized epithelial cell line NP-69 cells. Immunohistochemical staining was performed on paraffin sections of 88 cases of LSCC specimens and 16 cases of adjcent normal tissue samples to investigate the EphA2 protein expression, and to futher elucidate its correlation with clinicopathological characteristics.</p><p><b>RESULTS</b>Compared with the NP-69 cells, EphA2 expression in LSCC cell line Hep-2 cells was upregulated. The positive rates of EphA2 expression in LSCC and adjcent normal tissues samples were 80.7% and 43.8%, respectively, with a significant difference between the two groups (P < 0.001). EphA2 overexpresion was closely correlated with clinical stage (I + II/III + IV, P = 0.005), metastasis (P = 0.025) and recurrence (P = 0.021) in LSCC. Furthermore, patients with EphA2 overexpression had poorer tumor-free survival and 5-year overall survival compared with that in patients with low EphA2 expression (33.3% vs. 63.2%, P = 0.003; 46.7% vs. 81.6%, P = 0.002). EphA2 expression combined with clinical stage provided a better predictive value in prognosis. Univariate and multivariate Cox regression analysis revealed that EphA2 expression is an independent prognostic factor for patients with LSCC (P = 0.019).</p><p><b>CONCLUSIONS</b>The results of this study demonstrate that EphA2 protein expression is significantly increased in LSCC tissues and cell lines, and EphA2 protein overexpression is associated with tumor recurrence, metastasis and poorer prognosis in LSCC patients. These results suggest that EphA2 may play a critical role in the initiation and progression of LSCC, implicating EphA2 as a valuable marker for the prediction of recurrence, metastasis and prognosis in LSCC.</p>