Objective: To explore the influence of micro RNA-9(miR-9)on the down-regulation of NF-κB1 in esophageal carcinoma cell TE6. Method :The expression of mRNA of NF-κB1 in esophageal carcinoma cells TE6 by miR-9 was determined with RT-PCR

and the expression of protein of NF-κB1 in esophageal carcinoma cell TE6 by miR-9 was observed with Western blotting. Result: The expression of mRNA and protein of NF-κB1 in esophageal carcinoma cell TE6 were both up-regulated.The esophageal carcinoma cells which were transfected with negative control could not suppress the expression of mRNA and protein of NF-κB1

but the esophageal carcinoma cells which were transfected with miR-9 could significantly inhibit the expression of mRNA and protein of NF-κB1.The inhibition ratio were 73.21% and 87.63% respectively. Conclusion: The expression of NF-κB1 in esophageal cancer cell TE6 is significant down-regulated by miR-9.It provides a new way for prevention and tceat ment of esophageal carcinoma.