Objective      To identify the effects of 5-fluorouracil (5-FU) and vincristine (VCR) on stem cell-associated phenotypes and properties of gastric cancer cell line SGC-7901.       Methods      SGC-7901 cells were treated with 5-FU and VCR

respectively. Candidate stem cell markers of CD44 and CD133 as well as other stemness genes and epithelial-to-mesenchymal transition (EMT)-associated genes were assayed. Colony formation assay

sphere formation assay and tumorigenic formatio

n assay were used to test the properties of SGC-7901 cells associated with cancer stem cells.       Results      After 5-FU and VCR treatment

the mRNA expression levels of CD44 and CD133 significantly increased in all the doses as compared with the control group (up to 2.36±0.03

1.74±0.05

6.03±0.75 and 4.06±0.77 folds respectively

P

0.05)

but the capabilities of colony formation and tumorigenic formation had no change. VCR treatment manifested the EMT gene profile and showed different morphologic features in serum-free SGC-7901 cell culture

which was different from 5-FU treatment.       Conclusion      Transient treatment of 5-FU and VCR up-regulates the expression of CD44 and CD133. VCR induces EMT changes in SGC-7901 cells and enhances sphere formation in serum-free culture medium.