system
Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Acetylation, Adult, Antirheumatic Agents, Auranofin, Blotting, Western, Calcitriol, Cell Cycle, Cell Differentiation, Cell Line, Tumor, Child, Chromatin, Female, Flow Cytometry, Granulocytes, HL-60 Cells, Histones, Humans, Immunohistochemistry, Immunoprecipitation, Male, Middle Aged, Oncogene Protein p21(ras), Receptors, Retinoic Acid, Retinoic Acid Receptor alpha, Tretinoin.
user
Does auranofin promote retinoic acid- or dihydroxyvitamin D3-mediated cell differentiation of promyelocytic leukaemia cells by increasing histone acetylation? Context: To investigate the molecular mechanism for the effect of auranofin on the induction of cell differentiation, the cellular events associated with differentiation were analysed in acute promyelocytic leukaemia (APL) cells. The APL blasts from leukaemia patients and NB4 cells were cotreated with auroanofin and all-trans-retinoic acid (ATRA) at suboptimal concentration. The HL-60 cells were treated with auroanofin and a subeffective dose of 1alpha,25-dihydroxyvitamin D3 (1,25(OH)2 vit D3) in combination. The effect of auroanofin was investigated on histone acetylation at the promoter of differentiation-associated genes and expression of cell cycle regulators. Treatment with auroanofin and ATRA cooperatively induced granulocytic differentiation of fresh APL blasts isolated from patients and NB4 cells. The combined treatment also increased reorganization of nuclear PML bodies and histone acetylation at the promoter of the RARbeta2 gene. Auroanofin also promoted monocytic differentiation of the HL-60 cells triggered by subeffective concentration of 1,25(OH)2 vit D3. The combined treatment of auroanofin and 1,25(OH)2 vit D3 stimulated histone acetylation at p21 promoters and increased the accumulation of cells in the G0/G1 phase. Consistent with this, the expressions of p21, p27 and PTEN were increased and the levels of cyclin A, Cdk2 and Cdk4 were decreased. Furthermore, the hypophosphorylated form of pRb was markedly increased in cotreated cells.
assistant
These findings indicate that auroanofin in combination with low doses of either ATRA or 1,25(OH)2 vit D3 promotes APL cell differentiation by enhancing histone acetylation and the expression of differentiation-associated genes. Final Decision: yes