Splicing factor proline/glutamine-rich contributes to the sensitivity of acute myeloid leukemia HL-60 cells to doxorubicin / 白血病·淋巴瘤

ABSTRACT

Objective To investigate the anti-leukemia adriamycin (ADR) effect of membrane protein Splicing factor proline/glutamine-rich (SFPQ).Methods HL-60 and its adriamycin-resistant cells HL-60/ADR were cultured in vitro.Expression of SFPQ on HL-60 and HL-60/ADR cell membranes were examined by immunofluorescence.McAb 5D12 was used to block membrane SFPQ protein activity.ADR susceptibility and cell proliferation were analyzed by MTT assay.IC50 values of ADR in HL-60 and HL-60/ADR cell lines and up-regulations in cell proliferation induced by 5D12 were calculated.Intracellular accumulation of rhodamine in HL-60 and HL-60/ADR cells were measured using fluorescence-activated cell sorting.Results Expression of SFPQ on cell membrane was higher in HL-60 cells compared to the HL-60/ADR cell line.After membraneblocking with 5D12,ADR sensitivity was decreased in vitro compared with the untreated cells [the 48 h IC50 value,HL-60 cell line (0.19±0.03) μg/ml vs (0.95±0.13) μg/ml,HL-60/ADR cell line (14.41±2.42) μg/ml vs (21.33±4.26) μg/ml].Blocking of membrane SFPQ by 5D12 did not affect the intracellular accumulation of rhodamine in these cells,however,5D12 induced HL-60 and HL-60/ADR cell proliferation,following 1,3,5,8 and 12 μg/ml 5D12 treatment for 96 h were (9.12±2.02) ％,(16.63±0.92) ％,(19.04±0.25) ％,(24.17±0.53) ％,(34.04±3.20) ％ (HL-60),and (7.40±2.23) ％,(8.72±2.38) ％,(10.47±3.78) ％,(11.57±1.49) ％,(13.97±0.91) ％ (HL-60/ADR),respectively.Conclusion Nuclear protein-SFPQ contributes to HL-60′ ssensitivity to adriamycin by increasing its surface expression and promoting cell proliferation,but the protein has no significant effect on the intracellular accumulation of the drug.