ERBB and P-glycoprotein inhibitors break resistance in relapsed neuroblastoma models through P-glycoprotein

Area of Science:

• Oncology
• Molecular Biology
• Pharmacology

Background:

• Chemotherapy resistance is a major challenge in treating relapsed high-risk neuroblastomas.
• Identifying novel therapeutic strategies to overcome drug resistance is crucial for improving patient survival.

Purpose of the Study:

• To identify agents that can sensitize neuroblastoma cells to vincristine.
• To investigate the role of P-glycoprotein (P-gp/ABCB1) and ERBB signaling in chemotherapy resistance.

Main Methods:

• Screening of 15 drugs for their ability to sensitize neuroblastoma cells to vincristine.
• In vitro assays including trypan blue exclusion and apoptosis induction.
• In vivo studies using a zebrafish embryo xenograft model.
• Analysis of gene expression datasets from neuroblastoma cell lines and patient samples.

Main Results:

• Tariquidar, a P-gp inhibitor, and afatinib were identified as potent resistance breakers.
• P-gp inhibition, but not ERBB inhibition, significantly sensitized neuroblastoma cells to vincristine.
• P-gp inhibition demonstrated efficacy in both in vitro and in vivo models.
• P-gp plays a critical role in neuroblastoma resistance at relapse, while ERBB signaling has a minor role.

Conclusions:

• P-glycoprotein (P-gp/ABCB1) is a key mediator of vincristine resistance in relapsed high-risk neuroblastomas.
• Targeting P-gp offers a promising strategy to resensitize neuroblastoma to conventional chemotherapy.
• Further investigation into P-gp inhibition for neuroblastoma treatment is warranted.