ABSTRACT
AIM:To investigate the effect of suppression of mel18 gene on the differentiation of human acute myeloid leukemia cell line HL 60 induced by cinnamaldehyde ( CA) .METHODS:HL60 cells were treated with low con-centration of CA or all-trans retinoic acid (ATRA).shRNAmel18 vector and shRNALuc control vector were employed to package lentiviruses which were then used to infect HL 60 cells.The virus-infected HL60 cells were treated with low con-centration of CA , and ATRA was used as a positive control of differentiation-inducing agent .The differentiation markers on the cell surface and cell cycle of virus-infected HL60 cells were analyzed by flow cytometry .Western blot was used to deter-mine the expression of MEL18, cyclin D1 and p27, as well as the phosphorylation level of Akt .RESULTS:Low concen-tration of CA and ATRA increased the expression of granulocytic differentiation marker CD 11b on the HL60 cells, with the decreased expression of MEL 18 in the HL60 cells.The expression of MEL18 decreased in shmel18 virus-infected HL60 cells (shmel18-HL60 cells), but did not change in shLuc-HL60 cells.The expression of CD11b on shmel18-HL60 cells increased with G 1-phase arrest , which went even higher after treatment with CA .The phosphorylation level of Akt and the expression of cyclin D1 decreased in shmel18-HL60 cells with the increase in the expression of p27.CONCLUSION:In-hibition of mel18 gene leads HL60 cell granulocytic differentiation .mel18 gene may affect the differentiation of HL 60 cells by regulating cyclin D1 and p27 via PI3K/Akt signaling pathway.PI3K/Akt signaling pathway is also involved in CA-in-duced differentiation of HL60 cells by suppressing mel18 gene expression.
ABSTRACT
AIM:To investigate the effect of suppression of mel18 gene on the differentiation of human acute myeloid leukemia cell line HL 60 induced by cinnamaldehyde ( CA) .METHODS:HL60 cells were treated with low con-centration of CA or all-trans retinoic acid (ATRA).shRNAmel18 vector and shRNALuc control vector were employed to package lentiviruses which were then used to infect HL 60 cells.The virus-infected HL60 cells were treated with low con-centration of CA , and ATRA was used as a positive control of differentiation-inducing agent .The differentiation markers on the cell surface and cell cycle of virus-infected HL60 cells were analyzed by flow cytometry .Western blot was used to deter-mine the expression of MEL18, cyclin D1 and p27, as well as the phosphorylation level of Akt .RESULTS:Low concen-tration of CA and ATRA increased the expression of granulocytic differentiation marker CD 11b on the HL60 cells, with the decreased expression of MEL 18 in the HL60 cells.The expression of MEL18 decreased in shmel18 virus-infected HL60 cells (shmel18-HL60 cells), but did not change in shLuc-HL60 cells.The expression of CD11b on shmel18-HL60 cells increased with G 1-phase arrest , which went even higher after treatment with CA .The phosphorylation level of Akt and the expression of cyclin D1 decreased in shmel18-HL60 cells with the increase in the expression of p27.CONCLUSION:In-hibition of mel18 gene leads HL60 cell granulocytic differentiation .mel18 gene may affect the differentiation of HL 60 cells by regulating cyclin D1 and p27 via PI3K/Akt signaling pathway.PI3K/Akt signaling pathway is also involved in CA-in-duced differentiation of HL60 cells by suppressing mel18 gene expression.