Objective To explore the changes of Par-4 and WT1 genes expression during human leukemic K562 cells apoptosis induced by arsenic trioxide (As2O3). Methods After the K562 cells were treated with arsenic trioxide (2-10 μmol/L) for 24-72 hours, cell survival rate was evaluated by MTT assay and apoptosis was analyzed using flow cytometry. The expressions of mRNA and protein for par-4 and WT1 were tested by Real-time quantitative reverse transcriptase polymerase chain reaction (RQ-RT-PCR) method and Western blotting in K562 cells with various concentrations of arsenic trioxide at different time points. Results After the K562 cells were treated with As2O3 of different concentrations, arsenic trioxide could efficiently inhibit the growth of K562 cells and induce apoptosis with the increase of As2O3 concentration. The same time, the mRNA and protein expressions of Par-4 were up-regulated, while the mRNA and protein expression of WT1 were down-regulated. Conclusion Arsenic trioxide could inhibit the growth of K562 cells and induce apoptosis. Par-4 and WT1 genes could participate in the apoptosis of K562 cells induced by arsenic trioxide.

Objective To observe expressions of mRNA for Par-4 and WT1 in bone marrow cells from acute leukemia patients and non-leukemia patients, and to approach the correlation between CR rate and Par-4, WT1 expression level. Methods To detect Par-4 and WT1 mRNA expression level in bone marrow cells from 78 acute leukemia patients and 23 non-leukemia patients by means of Real-time Fluorescent Quantitation RT-PCR. Results FQ-RT-PCR result showed that Par-4 mRNA was expressed in bone marrow cells from 78 acute leukemia patients and 23 non-leukemia patients. Compared with control groups, the expression levels of Par-4 mRNA were significantly suppressed (9.35×10-4±8.4×10-5, P ＜0.05). Compared with initial treatment groups and relapse groups, the expression levels of Par-4 mRNA in remission groups were significantly up-regulated (1.26×10-3±1.1×10-4) but were still significantly lower than that in control groups (3.25×10-3±2.9×10-4). There was no significance difference between initial treatment groups and relapse groups. No apparent association was found between Par-4 expression level and CR rate (P ＞0.05). WT1 gene was overexpressed in bone marrow cells from acute leukemia patients(2.98× 10-3±2.1×10-4), but the expression levels of WT1 mRNA were significantly lower in bone marrow cells from control groups (7.25×10-5±6.7×10-6,P ＜0.05). Compared with initial treatment groups and relapse groups, the expression levels of WT1 mRNA in remission groups were significantly down-regulated (6.86×10-4±5.2× 10-5) but were still significantly higher than that in control groups. There was no significant difference between initial treatment groups and relapse groups.There was significant difference between different WT1 expression levels and CR rates (P ＜0.05). Conclusion The result of FQ-RT-PCR testing confirmed that Par-4 mRNA expression is lower, while WT1 is higher in acute leukemia. Par-4 and WT1 gene present mutually exclusive expression patterns. There was no apparent association between Par-4 expression level and CR rate.