AIM:To investigate the effect of antisense RNA to vascularendothelial growth factor_(165)(VEGF_(165))on human esophagealsquamous call carcinoma call line EC109 and the feasibilityof gene therapy for esophageal carcinoma.METHODS:Using subclone technique,the full length ofVEGF_(165)amino acid cDNA,which was cut from pGEM-3Zf(+),was cloned inversely into the eukaryotic expressionvector pCEP4.The recombinant plasmid pCEP-AVEGF_(165)was transfected into EC109 call with lipofectamine.After astable transfection,dot Blot,enzyme-linked immunosorbentassay(ELISA),laser confocal imaging system analysis,transmission electron microscopy and flow cytometry wareperformed to determine the biological characteristics ofEC109 call line before and after transfection in vitro andwhether there was a reversion in the tumorigenic propertiesof the EC109 call in vivo.RESULTS:The eukaryotic expression vector pCEP-AVEGF_(165)was successfully constructed and transfected into EC109calls.The expression of VEGF_(165)was significantly decreasedin the transfected calls while the biological characteristics ofthe calls ware not influenced by the expression of antisensegene.The tumorigenic and angiogenic capabilities waregreatly reduced in nude mica,as demonstrated by reducedtumorend volume(820±112.5)mm~3 vs(7930±1035)mm~3and(7850±950)mm~3,P<0.01)and microvessel density(8.5±1.2)mm~(-2)vs(44.3±9.4)mm~(-2)and(46.4±12.6)mm~(-2),P<0.01)in comparison between experimentalgroup,empty vector transfected group and control group.CONCLUSION:The angiogenasis and tumorigenicity ofhuman esophageal squamous call carcinoma were effectivelyinhibited by VEGF_(165)antisense RNA.Anfisense RNA toVEGF_(165)can potentially be used as an adjuvant therapy forsolid tumors. AIM: To investigate the effect of antisense RNA to vascularendothelial growth factor - (165) (VEGF_ (165)) on human esophageal squamous call carcinoma call line EC109 and the feasibility of gene therapy for esophageal carcinoma. METHODS: Using subclone technique, the full length of VEGF_ ( 165) amino acid cDNA, which was cut from pGEM-3Zf (+), was cloned inversely into the eukaryotic expression vector pCEP4. The recombinant plasmid pCEP-AVEGF_ (165) was transfected into EC109 call with lipofectamine. After astable transfection, dot Blot, enzyme-linked immunosorbentassay (ELISA), laser confocal imaging system analysis, transmission electron microscopy and flow cytometry wareperformed to determine the biological characteristics of EC109 call line before and after transfection in vitro andwhether there was a reversion in the tumorigenic properties of the EC109 call in vivo. RESULTS: The eukaryotic expression vector pCEP-AVEGF_ (165) was successfully constructed and transfected into EC109 clones. The expression of VEGF_ (165) w as significantly decreased the the transfected calls while the biological characteristics of the calls for not affected by the expression of antisense gene. tumorigenic and angiogenic capabilities ware reduced significantly in nude mica, as demonstrated by reduced tumor volume (820 ± 112.5) mm ~ 3 vs (7930 ± 1035 ) were significantly lower than those in the control group (P <0.01). The microvessel density (8.5 ± 1.2) mm -2 (44.3 ± 9.4) mm -2 and (46.4 ± 12.6) mm CONCLUSION: The angiogenasis and tumorigenicity ofhuman esophageal squamous calli were effectively inhibited by VEGF_ (165) antisense RNA.Anfisense RNA to VEGF_ (165) ~ (-2), P < can potentially be used as an adjuvant therapy forsolid tumors.