Vitamin D3, arsenic trioxide, or combination therapy for acute promyelocytic leukemia

Purpose: Arsenic trioxide (ATO) has been a highly promising chemotherapeutic drug for treating APL patients in the last decades. Owing to its complications, researchers are enthusiastic about applying compounds with fewer side effects, especially in a combined modality. Therefore, due to the anti-cancer properties of Vit-D-3, our investigation was aimed to highlight the Vit-D-3/ATO combination effects on the NB4 leukemic cells. Methods: The APL cell line (NB4) was cultured with various Vit-D-3, ATO, and Vit-D-3/ATO concentrations. Afterward, the cell viability was evaluated via MTT and trypan blue assays. In addition, the apoptosis and Gene expression were assessed using Flow cytometry and qRT-PCR, respectively. Results: Our findings revealed that Vit-D-3 applied apoptotic and growth inhibitory effects in a dose and time dependent manner. Moreover, Vit-D-3/ATO combination augmented the effects of ATO on regulated cell death via a remarkable elevation in the BAX/BCL-2 ratio in comparison with single treatments. Conclusion: Given the synergistic effects of the Vit-D-3/ATO combination, our study suggests a promising therapeutic strategy for APL treatment.