Abstract: Objective : To explore cytokines tumor necrosis factor-alpha ( TNF-a ) and S-Nitroso-Nacetyl-penicillamine ( SNAP, nitrix oxide donor, leads to hypoxia state in the culture medium . ) regulate to expression of vascular endothelial growth factor-A, C ( VEGF - A,C) in pancreatic cancer cells. Methods : The method of Northern blot and Western blot was respectively used to analyze the expression of gene and protein of VEGF- A,C in six human pancreatic cancer cells lines a n d the reverse-transcription polymerase chain reaction ( RT - PCR ) method was used to analyze VEGF-A,C gene expression in two tested cell lines under the stimulation with TNF -α or SNAP . Results : Northern blot analysis revealed the presence of the 4.1 - kb VEGF - A mRNA transcript and 2.4 - kb VEGF - C mRNA transcript in all six tested cell lines; Western blot analysis revealed the presence of Mr 43 - kDa VEGF -A protein and Mr 55 - kDa VEGF - C protein in all the cell lines. RT - PCR analysis showed that by stimulation with TNF - α, there werea1 - to 2.5-fold and 1 - to 2-fold decrease in COLO - 357 cell line,and a 1 -fold and 1.6 - to 2.5 - fold decrease in CAPAN - 1 cell line in the level of VEGF - A and of VEGF - C mRNA, respectively; The level of VEGF - A mRNA increased five times in COLO-357 cell line and four times in CAPAN - 1 cell line b y stimulation with SNAP, however, no effect was found in the two cell lines by stimulation with SNAP . Conclusions : Cytokines TNF - α and SNAP affect the bio-logical character of pancreatic cancer cells by regulating the expression of VEGF-A,VEGF-C, and promote the apotosis and death or the grow thand distant metastasis of pancreatic cancer cells.