Inhibiting ERK dimerization ameliorates BRAF-driven anaplastic thyroid cancer.

Area of Science:

• Oncology
• Molecular Biology
• Pharmacology

Background:

• RAS-to-ERK signaling is critical in advanced thyroid carcinoma.
• ERK dimerization inhibition offers a therapeutic strategy for carcinomas.
• DEL-22379 is a specific ERK dimerization inhibitor investigated for thyroid cancer.

Purpose of the Study:

• To analyze DEL-22379's effects on RAS-to-ERK signaling.
• To evaluate DEL-22379's impact on tumor processes in vitro and in vivo.
• To determine differential responses in BRAF- vs. RAS-mutant anaplastic thyroid carcinoma (ATC).

Main Methods:

• Utilized four human ATC cell lines with BRAF or RAS mutations.
• Assessed ERK dynamics and tumor characteristics.
• Performed RNA-sequencing for transcriptional landscape analysis and in vivo efficacy testing in an orthotopic mouse model.

Main Results:

• DEL-22379 impaired ERK activation in BRAF-mutant cells but not RAS-mutant cells.
• Cell viability and metastasis were reduced, primarily in BRAF-mutant cells.
• In vivo, tumor growth and dissemination were significantly reduced in BRAF-mutant and mildly in RAS-mutant models.

Conclusions:

• BRAF- and RAS-mutant thyroid cells exhibit distinct responses to DEL-22379.
• DEL-22379 shows significant anti-tumor activity against BRAF-mutant ATC with low toxicity.
• Driver mutation type is crucial for thyroid cancer progression and treatment considerations.