Integrative Genomic and Transcriptomic Analysis Reveals Targetable Vulnerabilities in Angioimmunoblastic T-Cell...

Area of Science:

• Oncology
• Immunology
• Genetics

Background:

• Nodal follicular helper T-cell (T_FH) lymphoma, angioimmunoblastic T-cell lymphoma (AITL) subtype, is associated with a poor prognosis.
• Understanding the genetic landscape of AITL is crucial for developing targeted therapies.

Purpose of the Study:

• To identify recurrent mutations and epigenetic alterations in AITL.
• To correlate genetic findings with clinical prognosis.
• To explore potential therapeutic targets for AITL.

Main Methods:

• Whole-exome sequencing (WES) of 124 AITL tumors.
• Transcriptomic and methylation analysis of 78 and 40 samples, respectively.
• Analysis of AITL-patient-derived-xenografts (PDX) and gene expression profiling (GEP).

Main Results:

• Recurrent mutations were found in epigenetic drivers (TET2, DNMT3A, IDH2, TET3, KMT2D) and genes regulating T-cell receptor (TCR) signaling and PI3K pathways (CD28, PLCG1, RHOA, PTEN, PHLPP2).
• Co-mutation of TET2, IDH2, and DNMT3A, as well as CD28 mutations/fusions, were associated with poor prognosis.
• Epigenetic alterations impacted TCR signaling, cytokine regulation, and apoptosis pathways.
• Low PHLPP2 mRNA expression predicted poor prognosis, and its loss enhanced PI3K activation in CD4+ T-cells.

Conclusions:

• AITL is characterized by mutations in epigenetic regulators and genes involved in T-cell signaling and PI3K pathway.
• Specific mutations and epigenetic alterations serve as prognostic markers.
• PHLPP2 and TET2 alterations represent potential therapeutic targets for AITL.