Objective: To investigate the effects of Realgar on procoagulant activity (PCA), tissue factor expression and tissue factor mRNA transcription in acute promyelocytic leukemia (APL) cell lines NB4 and MR2 cells.
Method: NB4 and MR2 cells were treated with 300 micrograms.L-1 Realgar PCA of the treated cells was detected using one-stage clotting assay. TF antigen was detected by ELISA and TFmRNA by semi-quantitive RT-PCR.
Result: The PCA and TF antigen level in NB4 and MR2 cells were significantly higher than that in HL-60 and K562 cells. Realgar could down-regulate the membrane PCA, TF antigen and TF mRNA transcription of NB4 and MR2 cells in a time-dependent manner.
Conclusion: Down-regulating TF expression and PCA of NB4 and MR2 cells by Realgar may be one of the mechanism of its improvement effect on DIC-related hemorrhage of APL patients.