The B-cell chronic lymphocytic leukemia (CLL)/lymphoma 11A gene (BCL11A) encodes a krüppel-like zinc finger protein, which is important in thymopoiesis and has been associated with hematopoietic malignancies. In this study, we investigated whether the downregulation of BCL11A mRNA by small interference RNA (siRNA) was capable of inducing apoptosis, and tested the effect of BCL11A siRNA combined with BCL2 siRNA in B lymphoma cell lines (SUDHL6, EB1). BCL11A siRNA was transfected into SUDHL6, EB1 cells with HiPerfect transfection reagents. After transient transfection with BCL11A siRNA, the expression levels of BCL11A mRNA and protein were assayed by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot analysis. The cell proliferation was determined by a cell counting kit-8 (CCK8) assay. Apoptosis was determined by morphological observation and flow cytometric analysis. The results showed that the expression levels of BCL11A mRNA and protein from SUDHL6, EB1 cells transfected with BCL11A siRNA decreased, compared with either the scrambled negative control siRNA group or untransfected cells group (P<0.05). Viability of cells transfected with BCL11A siRNA was less compared to cells transfected with control siRNA and untransfected SUDHL6, EB1 cells, respectively (P<0.05). BCL11A siRNA induced apoptosis in both SUDHL6 and EB1 cells. BCL11A siRNA combined with BCL2 siRNA significantly inhibited cell growth. Apoptotic rates of SUDHL6, EB1 cells treated with BCL11A siRNA combined with BCL2 siRNA significantly increased (P<0.05), compared with either the scrambled control (Sc) siRNA and BCL2 siRNA combination or BCL2 or BCL11A siRNA-treated cells alone. Findings of this study suggest the downregulation of BCL11A mRNA by siRNA was able to induce apoptosis. Moreover, BCL11A siRNA combined with BCL2 siRNA increased apoptosis in SUDHL6, EB1 cells. Thus, suppression of BCL11A expression may be a useful approach in the treatment of B lymphoma.
Keywords: B-cell chronic lymphocytic leukemia/lymphoma 11A; BCL2; EB1 cells; SUDHL6 cells; apoptosis; siRNA small interfering RNA.