Deep insight into the B-cell associated tertiary lymphoid structure and tumor immunotherapy

Prognostic role of tertiary lymphatic structures and their modulation by adjuvant FOLFOX in stage III colon cancer: a retrospective cohort study

Background

Stage III colon cancer (CC) presents a critical therapeutic challenge due to its high recurrence risk. Identifying robust prognostic biomarkers to guide adjuvant therapy decisions is urgently needed in clinical practice. Tertiary lymphoid structures (TLSs), as immune aggregates within the tumor microenvironment, have emerged as potential indicators of immunological activity and treatment response. The objective of this study is to evaluate the role of TLSs in stage III CC, focusing on their potential as prognostic markers and their influence on patient outcomes, particularly in relation to chemotherapy response.

Methods

This retrospective cohort study enrolled 613 patients with pathologically confirmed stage III CC from two cohorts: 374 from Harbin Medical University and 239 from The Cancer Genome Atlas Colon Adenocarcinoma (TCGA-COAD) external validation cohort. Overall survival (OS) was the primary outcome, with a median follow-up period of 62 months. TLSs were assessed via immunohistochemistry and categorized by density and location [intratumoral (T score), peritumoral (P score)]. Prognostic significance was evaluated using multivariate Cox regression. A murine model was used to assess the immunomodulatory effects of folinic acid, oxaliplatin, and 5-fluorouracil (FOLFOX) chemotherapy on TLS formation.

Results

TLSs were present in 54.0% and 50.2% of patients in Cohorts 1 and 2, respectively. TLSs enriched with CD8+ T cells and CD20+ B cells were associated with improved OS. Multivariate analysis identified TLS presence as an independent predictor of better survival [hazard ratio (HR) =0.256, 95% confidence interval (CI): 0.093-0.707; P=0.009]. Higher intratumoral TLS density (T score) correlated with lower mortality risk (T2 vs. T0: HR =0.173, P=0.003), whereas higher peritumoral TLS density (P3) predicted worse prognosis (HR =5.887, P=0.04). In vivo experiments confirmed that FOLFOX treatment enhanced TLS formation and increased infiltration of immune cells including B cells, CD4+/CD8+ T cells, and dendritic cells.

Conclusions

TLSs serve as a reliable, independent prognostic biomarker in stage III CC. Their spatial distribution carries distinct prognostic implications, and FOLFOX-induced TLS formation suggests a dual role in cytotoxicity and immune activation. Incorporating TLS assessment into clinical workflows may improve risk stratification and guide personalized treatment, especially in designing immunochemotherapy strategies.

Comprehensive Analysis of Tertiary Lymphoid Structures in Pancreatic Cancer: Molecular Characteristics and Prognostic Implications

Purpose:

The molecular properties of TLSs in pancreatic cancer are still not well comprehended. This research delved into the molecular properties of intratumoral TLSs in pancreatic cancer through the exploration of multi-omics data.

Methods:

Seven key genes were identified through Cox regression analysis and random survival forest analysis from a total of 5908 genes related to TLSs. These genes were utilized to construct a prognosis model, which was subsequently validated in two independent cohorts. Additionally, the study investigated the molecular features of different populations of TLSs from multiple perspectives. The model’ s forecasting accuracy was verified by analyzing nomogram and decision curves, taking into account the patients’ clinical traits.

Results:

The analysis of immune cell infiltration showed a notably greater presence of Macrophage M0 cells in the group at high risk than in the low-risk group. The pathway enrichment analysis demonstrated the activation among common cancer-related pathways, including ECM receptor interaction, pathways in cancer, and focal adhesion, in the high-risk group. Additionally, the methylation study revealed notable disparities in DNA methylation between two TLS groups across four regions: TSS200, 5’ UTR, 1stExon, and Body. A variety of notably distinct sites were linked with PVT1. Furthermore, by constructing a competing endogenous RNA network, several mRNAs and lncRNAs were identified that compete for the binding of hsa-mir-221.

Conclusion:

Overall, this research sheds light on the molecular properties of TLSs across various pancreatic cancer stages and suggests possible focal points for the treatment of pancreatic cancer.