Background and purpose:The cortical actin-binding protein,cortactin,participates in several functions in the cytoskeleton system,cellular signal transduction and cell adhesion.There is also increasing evidence that it regulates tumor invasion and metastasis.However,the role played by cortactin in laryngeal carcinoma has not been clearly delineated.The purpose of this experiment was to investigate the effect of silencing cortactin expression on the proliferation and invasion in the human laryngeal carcinoma cell line Hep-2.Methods:A plasmid from a siRNA targeting cortactin was constructed and transfected into a Hep-2 cell line.The siRNA interference efficiency of cortactin was determined by Western blot.The proliferation was measured by MTT assay and plate colony formation. The Transwell test was used to detect the migration and invasion ability of the Hep-2 cells.Empty plasmid-transfected Hep-2 and normal Hep-2 were used as control groups.Results:Compared to Hep-2 cells,the cortactin expression of pSilencer3.1-cortactin-siRNA/Hep-2 was 11.22%(P

LCRG1(laryngeal carcinoma related gene1,LCRG1),a new candidate tumor suppressor gene of laryngeal carcinoma.However,it is known little about the possible regulatory mechanisms of LCRG1 gene expression.Restriction endonuclease digestion was used to obtain a set of the 5',or 3'deletion mutants from the region(-169～+127) of the LCRG1 gene.It has been found that the minimal promoter of the LCRG1 gene is mapped at the region from-169～-57.Linker scanning mutational analysis in the region(-169～+127) of the LCRG1 gene was used to identify the crucial cis-elements within the promoter region,The key cis-elements are within the region from-137～-122.SP1,E2F1/DP1,EKLF and ZF9 transcription factor binding site sites were predicted in the region by bioinformatics analysis.Co-transfection with each of a panel of the expression plasmids of the known transcription factors with the relevant reporter construct indicates Sp1 is potent transcription factor for enhancement of the promoter activity,SP1 can also up-regulate the endogenous expression of LCRG1 gene.Electrophoretic mobility shift assay(EMSA) was applied to verify that the key cis-elements of LCRG1 gene exist sequence of Sp1 binding sites.The findings,which showed that the key cis-elements within the region from 137～-122 play an important role in expression of the LCRG1 gene,provide a novel evidence for further study of the function of LCRG1 gene.