EphA2 mediated vascular endothelial growth factor expression via the p38 MAPK signaling pathway in squamous cell carcinoma of the head and neck / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To investigate the regulatory effect of erythropoietin-producing hepatocellular receptor (EphA2) on the expression of VEGF protein, a pro-angiogenic factor, via p38 mitogen-activated protein kinase (p38 MAPK) signaling pathway in squamous cell carcinoma of the head and neck(SCCHN) in vitro.</p><p><b>METHODS</b>SCCHN Tu686 cells were transfected with EphA2 overexpression vector pEGFP-N1-EphA2. Western blot was used to detect the expression of p38 MAPK and enzyme-linked immunosorbent assay (ELISA) was applied to assay of VEGF. SB203580 as a inhibitor of p38 MAPK signaling pathway was used.</p><p><b>RESULTS</b>The expression of VEGF protein was significantly up-regulated in Tu686 cells transfected with EphA2 overexpression vector (535.31 ± 45.71) pg/ml, when compared with Tu686 cells transfected with empty vector (400.99 ± 33.50) pg/ml and Tu686 cells with no transfection (385.30 ± 33.50) pg/ml (F = 17.091, P < 0.01). The expression of phosphorylated p38 MAPK was obviously increased in Tu686 cells with EphA2 overexpression. SB203580 inhibited the expressions of VEGF and phosphorylated p38 MAPK proteins in Tu686 cells with EphA2 overexpression.</p><p><b>CONCLUSION</b>EphA2 can regulate the expression of VEGF protein and stimulate p38 MAPK signaling pathway.</p>

Expression of astrocyte elevated gene-1 protein and its clinical significance in laryngeal squamous cell carcinoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To assess the protein expression of astrocyte elevated gene-1 (AEG-1) in tissue specimens of laryngeal squamous cell carcinoma (LSCC), and to correlate its expression with clinicopathological parameters and prognosis in patients with LSCC.</p><p><b>METHODS</b>RT-PCR was used to assay the expression of AEG-1 mRNA in 13 pairs of LSCC tissues and their corresponding noncarcinoma epithelia. Immunohistochemistry was performed on paraffin-embedded tissue specimens to investigate the protein expression of AEG-1 in 88 cases of LSCC specimens and 15 cases of adjacent epithelial samples.</p><p><b>RESULTS</b>The expression of AEG-1 mRNA was significantly increased in LSCC tissues compared to adjacent noncarcinoma epithelial tissues (0.81 ± 0.17 vs. 0.23 ± 0.10;t = 10.337, P < 0.001). Meantime, the positive rate of AEG-1 protein in 88 cases of LSCC was 87.5% (77/88). However, 15 cases of adjacent noncarcinoma epithelial merely demonstrated negative or mild expression of AEG-1 protein. AEG-1 overexpression was closely correlated with T stage (χ(2) = 6.289, P = 0.018), clinical stage (χ(2) = 11.049, P < 0.01), metastasis (χ(2) = 20.859, P < 0.01) and recurrence(χ(2) = 13.459, P < 0.01). The overall survival rates of patients with AEG-1 overexpression and low expression were 35.9% and 86.4%, respectively (χ(2) = 23.409, P < 0.01). Multivariate Cox regression analysis revealed that AEG-1 expression was an independent prognostic factor (P = 0.016).</p><p><b>CONCLUSION</b>AEG-1 protein may play a critical role in the initiation and progression of LSCC, implicating its predictive value in prognosis.</p>

EphA2 promotes angiogenesis and metastasis of head and neck squamous cell carcinoma in vivo / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To investigate the effects of EphA2 on the angiogenesis and cervical lymph node metastasis of squamous cell carcinoma of the head and neck (SCCHN) in vivo.</p><p><b>METHODS</b>EphA2 short hairpin (shRNA) lentiviral particles were used to knockdown the expression of EphA2 in SCCHN cell line M2 with high lymph nodes metastasis rate. Stable clones, obtained by puromycin screening, were assayed by RT-PCR and Western blot to validate the gene silencing efficiency and were used to establish SCCHN metastatic xenograft mouse model. Hematoxylin-eosin staining was applied to identify cervical lymph node metastasis of SCCHN in xenografted tumors. Immunohistochemistry was used to observe microvessel density. Western blot was used to investigate the protein expressions of EphA2 and vascular endothelial, growth factor (VEGF).</p><p><b>RESULTS</b>EphA2 shRNA lentiviral particles efficiently decreased the mRNA and protein expressions of EphA2 in SCCHN cell line M2, which were further successfully utilized to establish SCCHN metastatic xenograft mouse model. Compared with xenografted tumors in control group, xenografted tumors in M2EphA2RNAi(+) group decreased significantly tumor volume [(430.7 ± 190.0) mm(3) (x(-) ± s) vs (1179.0 ± 289.4) mm(3)] and weight [(0.26 ± 0.10) g vs (0.54 ± 0.12) g] (both P < 0.05). More importantly, bilateral cervical lymph node metastasis rate in M2EphA2RNAi(+) was also greatly declined (Mann-Whitney U = 10.0, P < 0.05). Decreased protein expressions of EphA2 and VEGF and microvessel density were observed in M2EphA2RNAi(+) group (t = 26.751, P < 0.01).</p><p><b>CONCLUSIONS</b>Knockdown of EphA2 expression led to the inhibition of tumor growth and metastasis in SCCHN nude mouse model. More importantly, SCCHN angiogenesis was also impeded, which might be associated with the decreased expression of VEGF.</p>

Expression of HMGB1 protein in laryngeal squamous cell carcinoma and its clinical significance / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the expression of HMGB1 protein in tissue specimens of laryngeal squamous cell carcinoma (LSCC) and adjacent normal mucosa, and explore the correlation of HMGB1 protein expression with clinicopathologic features and prognosis in LSCC.</p><p><b>METHODS</b>Ninty-three cases of LSCC and 5 cases of adjcent mucosal tissue samples were included in this study. Immunohistochemical staining was performed on paraffin-embedded tissue specimens to examine the HMGB1 protein expression. The data were futher correlated with the clinicopathological features and prognosis of the LSCC patients.</p><p><b>RESULTS</b>The positive rates of HMGB1 expression in LSCC specimens was 87.1%, significantly higher than that in the adjcent normal mucosa samples (46.7%, P = 0.001), and its overexpresion was closely correlated with T stage (Chi2 = 10.878, P = 0.004), clinical stage (Chi2 = 21.115, P < 0.01), metastasis (Chi2 = 28.298, P < 0.01) and recurrence (Chi2 = 14. 923, P = 0.001) in patients with LSCC. Patients with HMGB1 overexpression had both poorer disease-free survival and poorer overall survival compared with that in patients with low HMGB1 expression (Chi2 = 13.815, Chi2 = 11.912; Both P < 0.01). Univariate and multivariate Cox regression analyses revealed that HMGBI expression is an independent prognostic factor for patients with LSCC.</p><p><b>CONCLUSIONS</b>The results of this study demonstrate that HMGB1 protein expression is significantly increased in LSCC tissues, and HMGB1 protein overexpression is associated with a poorer prognosis in patients with LSCC. These results suggest that HMGB1 may play a critical role in the initiation and progression of LSCC, implicating HMGB1 may become a valuable marker for the prediction of prognosis in patients with LSCC.</p>

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>