# Tertiary lymphoid structures-driven immune infiltration patterns and their association with survival in neuroblastoma

## TL;DR

This study identifies a 6-gene signature linked to tertiary lymphoid structures that predicts better survival in neuroblastoma patients and highlights CD200 as a potential treatment target.

## Contribution

A novel 6-gene TLS signature is proposed as a prognostic biomarker for neuroblastoma, with CD200 identified as a potential therapeutic target.

## Key findings

- A 6-gene TLS signature (CCL2, CCL4, CCL21, CD200, CXCR3, IGSF6) correlates with improved survival in neuroblastoma patients.
- The low-TLS risk group showed better event-free and overall survival, with higher immune cell infiltration, especially cytotoxic T cells.
- CD200 downregulation reduces NB cell invasiveness and migration, suggesting its potential as a therapeutic target.

## Abstract

Neuroblastoma (NB), a diverse childhood cancer, needs better prognostic markers for personalized treatment. The current clinical risk stratification system does not fully explain the high heterogeneity of tumor patients. Tertiary lymphoid structures (TLS), key in tumor immunity, may serve as new biomarkers, but their impact on NB prognosis is unclear.

We combined transcriptome data from NB cohorts GSE49710 and GSE62564, analyzing 37 TLS-related genes. A prognostic signature (CMLS) was created using machine learning and validated with Kaplan-Meier and receiver operating characteristic (ROC) curves. We also studied immune infiltration and gene expression patterns in NB tissues using single-cell sequencing and quantitative real-time polymerase chain reaction (qRT-PCR).

A 6-gene TLS signature predicted better survival in NB patients. High levels of CCL2, CCL4, CCL21, CD200, CXCR3, and IGSF6 correlated with improved survival. The low-TLS risk group showed better event-free and overall survival. Immune analysis indicated a higher immune cell presence, especially cytotoxic T cells, in this group. Single-cell sequencing revealed lower TLS gene expression in refractory recurrence samples. CD200 downregulation reduced NB cell invasiveness and migration.

Our study demonstrates that TLS-related genes play a crucial role in NB prognosis, with a 6-gene TLS signature (CCL2, CCL4, CCL21, CD200, CXCR3, and IGSF6) serving as a promising prognostic biomarker for NB. CD200 may be a potential target for inhibiting the biological behavior of NB cells.