Recurrent mTORC1-activating RRAGC mutations in follicular lymphoma

Area of Science:

• Oncology
• Genetics
• Molecular Biology

Background:

• Follicular lymphoma is an incurable B cell malignancy.
• Key signaling pathways like JAK-STAT, NOTCH, and NF-κB are frequently mutated.
• These mutations often overlap with those in diffuse large B cell lymphoma (DLBCL).

Purpose of the Study:

• To identify unique genetic mutations in follicular lymphoma.
• To investigate the role of RRAGC mutations in follicular lymphoma pathogenesis.
• To explore potential therapeutic targets for follicular lymphoma.

Main Methods:

• Utilized discovery exome and extended targeted sequencing.
• Analyzed somatic mutations in follicular lymphoma patient samples.
• Investigated the functional impact of RRAGC variants on mTORC1 signaling.

Main Results:

• Identified recurrent somatic mutations in RRAGC uniquely enriched in 17% of follicular lymphoma patients.
• Found that RRAGC mutations co-occurred with ATP6V1B2 and ATP6AP1 mutations.
• Demonstrated that RRAGC variants activate mTORC1 signaling and confer resistance to amino acid deprivation.

Conclusions:

• RRAGC mutations are activating and present in the dominant clone of follicular lymphoma.
• These mutations are stable during disease progression.
• RRAGC mutations represent a promising therapeutic target for follicular lymphoma.