Targeted Transcriptomic Profiling Identifies Biomarkers and Molecular Features Associated With Immunotherapy Response...

Classic Hodgkin lymphoma (CHL) is a highly curable disease. However, a subset of patients developed relapsed/refractory disease, underscoring the need for predictors of treatment response. Although immune checkpoint inhibitors have improved outcomes, many patients still experience suboptimal responses. A deeper understanding of the CHL transcriptomic landscape may improve patient stratification and guide treatment approaches. Targeted messenger RNA next-generation sequencing was performed on formalin-fixed paraffin-embedded CHL tissue using the HTG EdgeSeq Precision Immune-Oncology Panel (1392 genes) in treatment naive and postchemotherapy relapse treated with nivolumab-based protocols. Differential gene expression and pathway enrichment analyses were conducted to characterize tumor-intrinsic and microenvironmental features associated with disease biology and treatment response. Across all CHL samples (n = 25), we observed overexpression of immune checkpoint and immunoregulatory genes (CD274, CTLA-4, IL6, and IL13) and markers of macrophage-rich/matrix-remodeling microenvironment (CD163, MMP2, and TIMP1) alongside loss of B-cell identity and tumor suppression programs. Pathway analysis revealed activation of IL6/JAK/STAT3, TNF-α/NF-κB, KRAS_UP, and inflammatory response with reduced proliferative and metabolic activity. Immunotherapy nonresponders, both in the overall (n = 5; 20%) and the treatment-naive CHL (n = 2; 12%), displayed a proliferative, cytokine-activated, and immunologically cold phenotype. This includes shared overexpression of FADD, NFKB1, and TGFB1 and downregulation of SMAD7 together with activation of E2F, G2M, MYC, and PI3K/AKT/mTOR pathways and negative enrichment of TNF-α/NF-κB, IL6/JAK/STAT3, and inflammatory response. Postchemotherapy relapse (n = 8) exhibited adaptive immunoregulatory and stress response signatures (IL15, TNFSF18, MAPK8, and FUT4) along with reduced immune activation and loss of tumor suppressor signaling. This study highlights the biological complexity and transcriptional diversity underlying CHL and its tumor microenvironment. Immunotherapy nonresponders exhibited an "oncogene-driven" transcriptional profile independent of previous treatment status, whereas responders showed an "inflammatory immune-escape" phenotype, offering insight into mechanisms of resistance. Despite the limited sample size, these findings provide a foundation for larger precision-focused studies aimed at improving outcomes in CHL.