Peripheral T-cell lymphoma: molecular profiling recognizes subclasses and identifies prognostic markers

Area of Science:

• Hematology
• Oncology
• Molecular Biology

Background:

• Peripheral T-cell lymphoma (PTCL) is an aggressive hematologic malignancy with limited treatment options and poor prognosis.
• Accurate classification and prognostic markers are crucial for effective management of PTCL subtypes.

Purpose of the Study:

• To investigate the molecular differences between major PTCL histological subtypes using gene expression and mutational profiling.
• To identify novel diagnostic markers and prognostic factors for PTCL.
• To validate the current classification of PTCL into angioimmunoblastic T-cell lymphoma (AITL), PTCL with T follicular helper (TFH) phenotype, and PTCL not otherwise specified (NOS).

Main Methods:

• Analysis of 105 PTCL cases using a NanoString platform targeting 208 genes related to T-cell differentiation, oncogenes, tumor suppressors, and pathways.
• Comparative gene expression analysis across AITL, PTCL-TFH, and PTCL-NOS subtypes.
• Targeted sequencing of 62 genes in 76 PTCL cases to determine mutational profiles.

Main Results:

• Distinct gene expression signatures were identified for AITL, PTCL-TFH, and PTCL-NOS.
• RHOAG17V mutations were significantly more frequent in AITL (34.09%) and PTCL-TFH (16.66%) compared to PTCL-NOS.
• Multivariate analysis revealed gene sets capable of stratifying PTCL cases into different risk groups.
• Expression of B-cell genes emerged as an independent prognostic factor for AITL, irrespective of the International Prognostic Index (IPI).

Conclusions:

• The study supports the current classification of PTCL into AITL, PTCL-TFH, and PTCL-NOS based on molecular profiling.
• Identified gene sets and mutations serve as valuable markers for precise PTCL diagnosis and risk stratification.
• B-cell gene expression is a significant independent prognostic indicator in AITL, offering potential therapeutic insights.