TY - JOUR AB - Acute myeloid leukemia is a common hematological malignancy that often exhibits strong drug resistance when treated using conventional chemotherapy. Although numerous studies have been carried out to develop methods of overcoming drug resistance, the results have generally been unsatisfactory. CD40 ligand (CD40L) has been shown to improve the sensitivity of cancer cells to drug treatment. In the present study, Adriamycin (ADM)‑resistant human monocytic THP‑1 cells (THP‑1/A cells) were developed by incubating THP‑1 cells with increasing concentrations of ADM. Cells were transfected with CD40L vectors to explore the potential involvement of CD40L in regulating multidrug resistance (MDR) in cancer. Cell proliferation and viability were measured using the Cell Counting Kit‑8 assay; cell apoptosis was evaluated by flow cytometry, trypan blue staining and caspase‑3 activity; and the expression of MDR‑associated protein 1 (MRP1) and permeability glycoprotein (P‑gp) was analyzed using western blotting. The results revealed that the protein expression levels of MRP1 and P‑gp were downregulated by raised CD40L expression and that the combination of raised CD40L expression with daunorubicin (DNR), a drug from which ADM is derived, significantly increased the extent of cell apoptosis, indicating that drug resistance was effectively attenuated by CD40L. Collectively, these results suggested that CD40L may contribute towards reducing DNR resistance in THP‑1/A cells. AD - Department of Hematology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China AU - Feng,Zhongxin AU - Chen,Qi DA - 2020/03/01 DO - 10.3892/etm.2020.8452 EP - 2194 IS - 3 JO - Exp Ther Med KW - CD40 ligand acute myeloid leukemia THP‑1 cells drug resistance PY - 2020 SN - 1792-0981 1792-1015 SP - 2188 ST - Raised CD40L expression attenuates drug resistance in Adriamycin‑resistant THP‑1 cells T2 - Experimental and Therapeutic Medicine TI - Raised CD40L expression attenuates drug resistance in Adriamycin‑resistant THP‑1 cells UR - https://doi.org/10.3892/etm.2020.8452 VL - 19 ER -