[Effect of Six1,TGF-β,VEGF-C that promoting tumor lymphangiogenesis in human laryngeal carcinoma xenografts in nude mice]

Abstract

Objective:To research the effect of Six1,TGF-β,VEGF-C that promoting tumor lymphangiogenesis in human laryngeal carcinoma xenografts in nude mice. Method:Technology of RNA interference was used for silencing Six1 and TGF-β genes expression in laryngeal squamous cell, preparation Six1-targeting and TGF-β-targeting siRNA for transfecting into laryngeal squamous cell carcinoma, sieve out positive clone cell and amplify. Preparing bearing cancer mice, the mice were divided into five groups, group A (untransfected),group B(empty vector), group C(Six1-siRNA),group D(TGF-β-siRNA),group E(Six1+TGF-β-siRNA). 6-12mm when the tumor has grown, the mice were sacrificed by cervical. The size of each tumor and metastasis were observed and recorded.The protein expression of Six1,TGF-β and VEGF-C was determined by immunohistochemistry and Western blot.The mRNA of Six1,TGF-β and VEGF-C was determined by RT-PCR. Result:The average tumor volume and the number of metastasis cases in group B have no statistically significant compared with group A. The average tumor volume in group C, group D and group E has no significantly reduced, but there is a clear reduction of the number of metastasis cases compared with group A. The average tumor volume and number of metastasis cases in group E has no significantly reduced compared with group C and group D. Both protein and mRNA expression of Six1, TGF-β and VEGF-C in group B had no significant difference compared with group A. In group C, group D and group E,both protein and mRNA expression of VEGF-C was decreased,difference has statistically significant compared with group A. Both protein and mRNA expression of VEGF-C in group E had no significant difference compared with group C and group D. Conclusion:Both Six1 and TGF-β can mediate tumor lymphangiogenesis and lymph node metastasis by mediate the expression of VEGF-C. Suggest that Six1,TGF-β might be a potential therapeutic target for preventing lymph node metastasis of tumor.

Keywords: carcinoma,squamous cell; laryngeal neoplasms; nude mice; sine oculis homeobox homolog 1; transforming growth factor-β; vascuoar endothelial growth factor C.