Melanoma Therapeutic Strategies that Select against Resistance by Exploiting MYC-Driven Evolutionary Convergence

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• BRAF-mutant melanoma often develops resistance to targeted therapies like BRAF/MEK inhibitors.
• Identifying the molecular mechanisms driving this resistance is crucial for improving patient outcomes.

Purpose of the Study:

• To investigate the key molecular pathways driving resistance to BRAF/MEK inhibitors in BRAF-mutant melanoma.
• To identify potential therapeutic strategies to overcome or prevent treatment resistance.

Main Methods:

• Statistical modeling of genomic data from pre-treatment and post-relapse patient tumors.
• Functional studies using over 20 in vitro and in vivo melanoma resistance models.
• Genetic and pharmacological inhibition of identified resistance pathways.

Main Results:

• Multiple resistance pathways converge on the activation of the transcription factor c-MYC (MYC).
• MYC activation is both necessary and sufficient for BRAF/MEK inhibitor resistance.
• Inhibiting MYC activity resensitized resistant melanoma cells to BRAF/MEK inhibitors.
• MYC-driven resistant cells showed hypersensitivity to targeting synthetic lethal partners of MYC, including specific kinases and metabolic pathways.

Conclusions:

• c-MYC (MYC) is a central regulator of BRAF/MEK inhibitor resistance in melanoma.
• Targeting MYC or its synthetic lethal partners offers a promising strategy for combination therapies to overcome resistance.
• These findings provide a framework for designing novel treatment regimens to achieve durable control of BRAF-mutant melanoma.