Selective gene dependencies in MYCN-amplified neuroblastoma include the core transcriptional regulatory circuitry

Area of Science:

• Oncology
• Genetics
• Molecular Biology

Background:

• Childhood high-risk neuroblastomas with MYCN gene amplification present significant therapeutic challenges.
• Identifying tumor-specific gene dependencies is crucial for developing novel targeted therapies.

Purpose of the Study:

• To identify genes essential for the growth and survival of MYCN-amplified neuroblastoma.
• To elucidate the core regulatory circuitry (CRC) maintaining cell state in these tumors.
• To evaluate therapeutic strategies targeting the CRC.

Main Methods:

• Genome-scale CRISPR-Cas9 screening was employed to identify selective gene dependencies.
• Chromatin-immunoprecipitation sequencing was used to map the transcriptional core regulatory circuitry.
• Combination therapy with BRD4 and CDK7 inhibitors was tested in vitro and in vivo.

Main Results:

• 147 candidate gene dependencies selective for MYCN-amplified neuroblastoma were identified.
• A core regulatory circuitry comprising MYCN, HAND2, ISL1, PHOX2B, GATA3, and TBX2 was defined.
• Combined BRD4 and CDK7 inhibition synergistically downregulated CRC gene expression, impacting tumor cells.

Conclusions:

• This study defines critical dependency genes in MYCN-amplified neuroblastoma.
• The identified core regulatory circuitry is essential for tumor cell state and survival.
• Targeting the CRC with combined inhibitors represents a potential therapeutic approach for neuroblastoma.