Bcl-2 hijacks the arsenic trioxide resistance in SH-SY5Y cells

Area of Science:

• Oncology
• Molecular Biology
• Cell Biology

Background:

• Arsenic trioxide (ATO) is a potent anti-leukemia agent, inducing apoptosis and differentiation in cancer cells.
• Despite its efficacy, the development of ATO drug resistance in leukemia remains a significant clinical challenge.
• Understanding the molecular mechanisms underlying ATO resistance is crucial for improving therapeutic outcomes.

Purpose of the Study:

• To investigate the mechanisms of acquired resistance to arsenic trioxide (ATO) in leukemia cells.
• To identify key molecular players that regulate sensitivity or resistance to ATO treatment.
• To explore the role of Bcl-2 in mediating ATO resistance.

Main Methods:

• Selection and characterization of ATO-resistant SH-SY5Y cell lines.
• Analysis of apoptosis, necroptosis, autophagy, NF-ƘB, and MAPK signaling pathways.
• Assessment of mitochondrial morphology in ATO-sensitive and resistant cells.
• Evaluation of ATO efficacy in xenograft tumor models in nude mice.

Main Results:

• Bcl-2 was identified as a critical regulator of ATO sensitivity in SH-SY5Y cells.
• Necroptosis, autophagy, NF-ƘB, and MAPK pathways were found not to be involved in ATO-induced apoptosis.
• ATO-resistant cells exhibited distinct mitochondrial morphology compared to ATO-sensitive cells.
• Xenograft tumors derived from ATO-sensitive cells showed greater sensitivity to ATO than those from resistant cells.

Conclusions:

• Acquisition of ATO resistance in cancer cells is associated with increased Bcl-2 expression.
• Bcl-2 upregulation is a key mechanism contributing to ATO drug resistance in leukemia.
• Targeting Bcl-2 may represent a therapeutic strategy to overcome ATO resistance.