ABSTRACT
OBJECTIVE: To investigate the proteasome inhibitor bortezomib induces acute myelogenous leukemia cell lines TF1 and NB4 apoptosis and its effect on SALL4 gene expression. METHODS: Cell proliferations were analyzed by MTT assay. Flow cytometry was used to analyze cell apoptosis rate. SALL4 protein was detected by immunocytochemistry. The expressions of SALL4 gene were detected by Real-time PCR. SALL4 proteins in two cell lines were detected by Western Blotting. RESULTS: MTT assay showed bortezomib inhibited the proliferations of two cell lines in a time-and-does manner. TF1 and NB4 cells' 48 h IC50 were (29.15 ± 0.55) and (30.55 ± 0.74) nmol · L-1 respectively. Flow cytometry showed bortezomib could induce apoptosis of two cell lines in a dose-dependent manner. Immunocytochemistry analysis revealed that both of two cell lines expressed SALL4 proteins which located in cell nucleus. Real-time PCR demonstrated that SALL4 genes were down-regulated after cells were treated by different concentrations(10, 30, 50 nmol · L-1) of bortezomib for 24 h, and bortezomib 50 nmol · L-1 groups' genes were down-regulated to 45.11% (TF1) and 69.77% (NB4) respectively comparing with the control groups (P < 0.05). Western blotting revealed that both of the cell lines expressed SALL4B proteins and which could be inhibited by bortezomib in a time-and-does manner. CONCLUSION: Bortezomib can significantly inhibit two cell lines proliferation and induce apoptosis, meanwhile down-regulate the expressions of SALL4 gene. Copyright 2012 by the Chinese Pharmaceutical Association.