[Effects of RhoA siRNA on the proliferation, adhesion, migration and invasion of tongue squamous cell carcinoma Tca8113 cells in vitro].

OBJECTIVE: to investigate the effect of RhoA on the metastasis of tongue squamous cell carcinoma Tca8113 cells in vitro. METHODS: a group of RhoA specific small interfering RNAs (siRNA) was constructed and confined by sequencing analysis. The siRNA of RhoA gene was transfected into human tongue squamous cell carcinoma Tca8113 cells line by Lipofectamine(TM) 2000. The protein transient expression of RhoA in the transfectants was examined 48 h after transfection. The cell line with stable expression of siRNA of RhoA was obtained by blasticidin screening and colony culture. Cell growth rate was determined with a cell counting. Millicell chambermodel and wound healing assay were used to examine the abilities of migration and invasion, respectively in vitro. RESULTS: RhoA was overexpressed in tongue squamous cell carcinoma Tca8113 cell line. Silencing of endogenous RhoA gene expression in Tca8113 cells resulted in inhibition of the proliferation, adhesion, chemotaxis and invasion of Tca8113 cells in vitro. CONCLUSIONS: RhoA siRNA inhibits the proliferation, adhesion, chemotaxis and invasion of oral squamous cell carcinoma Tca8113 cell lines. siRNA of RhoA is a potential factor controlling the proliferation and metastasis of Tca8113 cells. RhoA may play an important role in metastasis of oral squamous cell carcinoma.

[Coexpression of Schwann cell marker GFAP and myoepithelial cell marker alpha-SMA in salivary adenoid cystic carcinoma].

OBJECTIVE: To observe the expression of Schwann cell marker GFAP and myoepithelial cell marker alpha-SMA in salivary adenoid cystic carcinoma (ACC), and to evaluate the relationship of GFAP, alpha-SMA and perineural invasion in ACC. METHODS: Immunohistochemical SABC method, double-label immunofluorescence and CLSM were used to detect the expression of GFAP and alpha-SMA proteins in salivary ACC tissue samples. RESULTS: In salivary ACC tissue samples, both GFAP and alpha-SMA proteins were positive, which were coexpressed in cytoplasm of the same onco-myoepithelial cells. CONCLUSIONS: There may be Schwann cell differentiation in onco-myoepithelial cell of salivary ACC, and it may be the pathological base of perineural invasion in salivary ACC.

[Anti-tumor immune response in vitro induced by fusion of Tca8113 cells with macrophages].

OBJECTIVE: To evaluate the therapeutic effectiveness of fusion tumor vaccine in tongue cancer treatment. METHODS: Human macrophages fused with human tongue carcinoma cell line Tca8113 cell. The fusion cells were selected by magnetic cell sorting (MACS) and cultured. The biological properties of fusion cells and anti-tumor immune response in vitro induced by fusions were observed. RESULTS: In contrast to Tca8113, the fused cells grew significantly slow in vitro. The expression of MHC I, II antigen of the fusion cells which was detected by flow cytometry (FCM) was higher than that of Tca8113. The fused cells significantly increased the proliferation of mixed lymphocyte and induced their cytotoxicity on parental Tca8113. CONCLUSIONS: The fusion tumor vaccine of macrophages and OSCC cells increase in vitro immunogenicity significantly. This indicates that fusion tumor vaccine could be a new method of anti-tumor immunotherapy, which has important potentials for effective individualized human OSCC vaccine.

[Construction and expression of eukaryotic expression vector containing hVEGF165 gene in rat bone marrow stroma cell].

AIM: To construct the eukaryotic expression vector containing human vascular endothelial growth factor 165(VEGF165) gene and express it in rat bone marrow stroma cells(rMSCs). METHODS: The recombinant plasmid pSP73-VEGF165 was digested with BamH I and Xho I. Then the hVEGF165 gene segment obtained was again cloned into pcDNA3.1 to construct recombinant eukaryotic expression vector pcDNA3.1-VEGF165. Then the recombinant vector was identified by enzyme digestion analysis and sequencing. The rMSCs were transformed by recombinant vector and positive clones were screened with G418. The expression of hVEGF165 gene in the transformed cells was detected by immunocytochemical staining. RESULTS: Enzyme digestion analysis and sequencing showed that target gene had been cloned into recombinant vector. The expression of hVEGF165 gene in the transformed cells had been demonstrated by immunocytochemical staining. CONCLUSION: The recombinant eukaryotic expression vector has been constructed and expressed successfully in the transformed cells. Therefore, it is possible to use the rMSCs expressing hVEGF165 gene as seed cells in the bone tissue-engineering.

[Structural mechanism studies of hTNF alpha mutants in position 30 and 42 amino acid].

OBJECTIVE: To study the relationship between the structure and functional activity of hTNF alpha. METHODS: Four hTNF alpha mutants were constructed, different binding structures and gene responses related with these mutants were studied by the methods of immunoprecipitation and mRNA differential display. RESULTS: The specific activities and LD50 of the different hTNF alpha mutants indicated their different bioactivities. It was shown that the hTNF alpha mutants had the relative binding affinities to the wild types. The mRNA differential display assay proved that the hTNF alpha mutants stimulated different gene responses. CONCLUSION: These results suggest that the specific anti-tumor activities of hTNF alpha mutants are accomplished by inducing different or same gene response at different quantities after its binding to specific receptor.