The Expression And Significance Of MicroRNA Let-7and K-ras In Esophageal Squamous Cell Carcinoma

Objective:To investigate the expression and clinical significance of microRNA let-7and its downstream protein K-ras in both esophageal squamous cell carcinoma(ESCC)and corresponding paracancerous tissues,exploring the correlation between them and analyzing the mechanism of their action in ESCC.Methods:Clinical data of38ESCC patients receiving esophagectomy in our department from January to June in2010were collected.The expression of let-7and K-ras were detected in paraffin sections of ESCC and corresponding paracancerous tissues(control group).There were38eligible cases containing29male patients and9female patients, aged from48to80(average64.53). Real-time quantitative polymerase chain reaction(qRT-PCR) and Immunohistochemistry(Elivision method) were performed to detect the expression of microRNA let-7and K-ras separately in both in both esophageal squamous cell carcinoma(ESCC) and corresponding paracancerous tissues. T test,Chi-Squared and variance analysis were used to analyze the correlation between the let-7,K-ras expression and clinical parameters(such as age,sex,depth of tumor invasion,differentiation,TNM stage and lymph node metastasis),and also the relationship between let-7and K-ras.Results:(1There was significant difference in the expression of let-7in ESCC tissues and corresponding paracancerous tissues.(2)The positive rate of K-ras was28.9%(11/38) in ESCC tissues,while zero in paracancerous tissues.(3)There were no statistically significant correlation between the experssion of let-7,K-ras in ESCC tissues and clinical parameters(such as age,sex,depth of tumor invasion,differentiation,TNM stage and lymph node metastasis).(4)There were statistically significant difference of the let-7expression in ESCC tissues between K-ras positive group and negative group. Conclusion:(1)The expression of let-7was higher in paracancerous tissues than in ESCC tissues.(2)There were no significant correlation between the experssion of let-7,K-ras in ESCC tissues and clinical parameters(such as age,sex,depth of tumor invasion,differentiation,TNM stage and lymph node metastasis).(3)There were significant difference of the let-7expression in ESCC tissues between K-ras positive group and negative group.