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

BACKGROUND

Tissue-resident memory T cells (TRMs), 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.

METHODS

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.

RESULTS

Of the 141 PMCC patients, 29% (n = 30/103) of NPC tumors had high CD103+ ITIC (defined as ≥ 30%) linked with TRM 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.

CONCLUSIONS

Despite similarities to other virally driven tumors, CD103+ ITIC abundance was not prognostic in NPC, highlighting the need for better characterization of TRMs subpopulations.