The Effect Of ACTL6A On Differentiation In APL Cells And Its Related Mechanism

PART ? KNOCKDOWN OF ACTL6 A PROMOTES DIFFERENTIATION OF APL CELLSBackground and Objective: Actin like 6A,a member of the Arps family,forms the chromatin remodeling complexes.It plays an important role in inhibiting differentiation in a variety of tumor diseases.However,the role of ACTL6 A in acute promyelocytic leukemia(APL)is rarely reported.In this study,we investigated the effect of knockdown of ACTL6 A on differentiation in APL cells.Methods: The expression of ACTL6 A in APL patients was determined by analyzing the APL cDNA microarray(GSE12662)in NCBI database.The differentiation of NB4 and HL-60 cell lines was induced by ATRA,and HL-60 cell lines were induced by PMA.The changes of ACTL6 A mRNA and protein levels were observed.ACTL6 A was knocked down by lentivirus as a vector at the gene level,and the differentiation marker CD11 b and morphological changes in APL cell lines were observed.The fluorescence expression of the protein was detected by immunofluorescence.The morphological changes were observed by Wright staining.Results: The expression of ACTL6 A in APL patients was up-regulated compared with that in normal control.The expression of ACTL6 A decreased gradually during the differentiation of NB4,HL-60 cells induced by ATRA and HL-60 cells induced by PMA.Besides,knockdown of ACTL6 A promoted the differentiation of NB4 and HL-60 cells.Conclusion: ACTL6 A is highly expressed in APL patients.ACTL6 A expression is decreased gradually during ATRA-or PMA-induced differentiation in NB4 and HL-60 cells.Knockdown of ACTL6 A promotes differentiation in APL cells.PART ? STUDY ON THE MECHANISM OF ACTL6 A AFFECTING THE DIFFERENTIATION OF APL CELLSObjective: To investigate the mechanism of APL cell differentiation by knockdown of ACTL6 A.Methods: ACTL6 A was knocked down to detect the activity change of Notch1 signaling pathway.The co-localization of ACTL6 A and Sox2?ACTL6A and p53 was detected by immunofluorescence.The interaction between ACTL6 A and Sox2?ACTL6A and p53 was detected by co-ip.APL cells were treated with Notch1 signaling pathway inhibitor DAPT and p53 activator CBL0137,respectively.The changes of CD11 b and ACTL6 A in m RNA and protein levels were detected by q RT-PCR and Western blot.Results: In this study,we found that the activity of Notch1 signaling pathway was up-regulated while knockdown of ACTL6 A promoted APL differentiation.ACTL6 A interacted with and was co-localized with Sox2 and p53.The protein expression of CD11 b was up-regulated and Notch1 signaling pathway was decresed in APL cells treated with DAPT.The protein level of CD11 b was up-regulated and the expression of ACTL6 A and Notch1 signaling pathway was down-regulated in APL cells treated with CBL0137.Conclusion: ACTL6 A interacts with p53 in acute promyelocytic leukemia cell lines to affect differentiation via the Notch1 signaling pathway.