[p21(WAF1) Gene Transfection Inhibits Proliferation of Leukemia Cell Line K562]
To explore the functional role of p21(WAF1) gene on the proliferation of leukemia cell line K562, a p21(WAF1) retroviral expression vector was constructed. Mediated by FuGENE trade mark 6, p21(WAF1) was transfected into leukemia cell line K562, which was without p21(WAF1) expression. After selected in G418, K562 cell clones that expressed p21(WAF1) stabaly were isolated and named K562-p21(WAF1). The ectopic expression of p21(WAF1) mRNA and protein in K562 cells was identified by RT-PCR and Western Blot. The cell proliferaton was tested in liquid and soft agar culture after transfection. The cell cycle was tested by FCM. The expression of p21(WAF1) protein and mRNA could be detected in K562-p21(WAF1) cells. A strong inhibition of cell proliferation was observed in K562-p21(WAF1) cell clones cultured in liquid media as well as soft agar (P < 0.01). The cell number in G(0)/G(1) phase was remarkably increased. The findings showed that p21(WAF1) can inhibit the proliferation of leukemia cells, and it could be a potential target gene for leukemia gene therapy.