ObjectiveTo investigate that the TGF- beta/Smad signaling pathway mediated epithelial mesenchymal transition (EMT) in trachea stenosis after transplantation. Methods180-220 g male rats (n=50) were randomly divided into a control group and an experimental group. no surgical operation rats were in the control group. tracheal transplantation rats (Wistar-SD rat) were in the experimental group. Graft specimens were obtained in rats on 3,7,10,14,35,90 days after operation. HE staining is used to explain the fibrosis degree of tracheal stenosis. The fibrosis degree of tracheal stenosis was detected by calculating the fibrosis rate. Immunohistochemical staining was used to detect transplanted tracheal, such as EMT related molecules E-cadherin, vimentin, alpha-SMA expression, p-Smad2/3 expression and transcription factor ZEB1, Snail1 expression in tracheal graft specimens. ResultsHE staining showed that the tracheal fibrosis rate of the control group was 0.171±0.020, fibrosis rate was 0.537±0.013 (P < 0.01) on the third day after transplantation. The result of immunohistochemical staining showed that vimentin positive epithelial cells increased significantly (P < 0.05). E-cadherin expression significantly reduced (P < 0.05). Compared with the control group, TGF- beta expression increased (P < 0.05) in the experiment group. Compared with the control group, the expression of p-Smad2/3, the transcription factor ZEB1 and Snail1 significantly increased (P < 0.05) in the experiment group. ConclusionMechanism of tracheal stenosis may be due to EMT. At the same time, TGF- beta/Smad signaling pathway and transcription factor ZEB1, Snail1 may regulate the EMT.
ObjectiveTo reveal the true value of plasma detection of epidermal growth factor receptor (EGFR) mutation for early-stage non-small cell lung cancer (NSCLC) gene diagnosis and to predict survival prognosis. MethodsTissue samples of positive EGFR mutations by using amplification refractory mutation system (ARMS) method were surgically resected from 198 patients with stage I-IV NSCLC between February 2014 and June 2015 in Tangdu hospital. Paired blood samples were collected before surgery. And the cellfree DNA (cfDNA) in plasma was extracted, plasma EGFR mutations were detected by real-time polymerase chain reaction (PCR). Concentration of cfDNA was measured by ultraviolet spectrophotometry. Follow-up observation for stage ⅢA patients was put into force after surgery. Kaplan-Meire was used in survival analysis. ResultsThe sensitivity of EGFR mutation for the 198 paired tissues and plasma samples was 17.2%.The sensitivity was positively correlated with TNM stage and negatively correlated with tumor differentiation. The sensitivity of sage ⅢA was 33.3%, significantly higher than that of the patients at stage ⅠA (1.6%, P=0.000) and stage ⅠB (7.9%, P=0.004). The sensitivity of poor differentiation was 36.8%, significantly higher than that of high differentiation (0.0%, P=0.000) and moderate differentiation (15.7%, P=0.010). There was no correlation between plasma cfDNA concentration and patient characteristics. Survival analysis showed that plasma detection was a vital factor for predicting postoperative survival prognosis of stage ⅢA patients (P=0.014). ConclusionTissue samples cannot be replaced by plasma samples for epidermal growth factor receptor (EGFR) mutation test in early-stage NSCLC patients, currently. When the sensitivity increases dramatically in the plasma samples of stage ⅢA NSCLC and poor differentiation tumor, we recommend using plasma detection for gene diagnosis, dynamic monitoring of EGFR mutations in stage ⅢA or poorly differentiated tumors, especially in NSCLC patients whose tissue samples cannot be obtained by surgery. And plasma EGFR detection is a valuable method of forecasting survival prognosis for locally advanced NSCLC patients.