Examining CD103⁺ Tissue-Resident Memory T Cells in Nasopharyngeal Carcinoma.

Abstract

Tissue-resident memory T cells (T_RMs), identified by CD103 expression, play key roles in infection and cancer and often correlate with improved survival in the latter. Their characterization in nasopharyngeal carcinoma (NPC) is of interest due to its viral etiology. NPC tumors from patients treated at Peter MacCallum Cancer Centre (PMCC; 2000-2017) were examined for CD103⁺, CD8⁺ T cells, and PD-L1 abundance, correlated with survival, and underwent NanoString transcriptomic analysis. Additional cohorts from Hong Kong and Singapore were assessed for CD103⁺ intra-tumoral immune cell (ITIC) abundance. Of the 141 PMCC patients, 29% (n = 30/103) of NPC tumors had high CD103⁺ ITIC (defined as ≥ 30%) linked with T_RM gene expression, immune checkpoints, and upregulated pathways in T-cell activation. Abundance of CD103⁺ ITIC was not associated with improved survival (PMCC: HR = 0.9, 95% CI: 0.4-2.1) across all cohorts. Despite similarities to other virally driven tumors, CD103⁺ ITIC abundance was not prognostic in NPC, highlighting the need for better characterization of T_RMs subpopulations.