CXC ligand 13 orchestrates an immunoactive microenvironment and enhances immunotherapy response in head and neck squamous cell carcinoma.

Objectives: This study aims to systematically explore the role of chemokine CXC ligand 13 (CXCL13) in head and neck squamous cell carcinoma (HNSCC). Methods: The Genotype-Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) databases provided the RNA-seq data for cancer and normal tissues, respectively. Gene set enrichment analysis was applied to search the cancer hallmarks associated with CXCL13 expression. TIMER2.0 was the main platform used to investigate the immune cell infiltration related to CXCL13. Immunohistochemistry was applied to explore the relationship between CXCL13 and patients' prognosis and the relationship between CXCL13 and tertiary lymphoid structures (TLSs). Results: The expression of CXCL13 was upregulated in most tumors, including HNSCC. The higher expression of CXCL13 was closely related to the positive prognosis of HNSCC. CXCL13 was mainly expressed in B cells and CD8 + T cells, revealing the relationship between its expression and immune activation in the tumor microenvironment. Furthermore, immunohistochemistry and multiple fluorescence staining analysis of HNSCC samples showed a powerful correlation between CXCL13 expression, TLSs formation, and positive prognosis. Finally, CXCL13 significantly increased the response to cancer immunotherapy. Conclusions: CXCL13 may function as a potential biomarker for predicting prognosis and immunotherapy response and associate with TLSs in HNSCC.

Use of cerebrospinal fluid CXCL13 concentration for diagnosis and monitoring of neurosyphilis: a three-case report

Introduction: Previous retrospective studies have demonstrated that the concentration of chemokine ligand CXCL13 in cerebrospinal fluid (CSF-CXCL13) is a promising biomarker in the diagnosis of neurosyphilis and, additionally, in the monitoring of therapeutic efficacy. Objective: To describe three cases of patients with neurosyphilis (NS) treated at Hospital Universitário Gaffrée e Guinle, in Rio de Janeiro, Brazil, with suspected active syphilis with neurological symptoms. Case report: Three patients from Rio de Janeiro, Brazil, were investigated for symptomatic NS. The concentration of CSF-CXCL13 was prospectively performed by enzyme-linked immunosorbent assay (ELISA) in all participants at baseline and in follow-up visits at 3 months after therapy. CSF-CXCL13 concentrations were significantly higher in all three patients with established NS. The CSF-CXCL13 concentrations decreased after 3 months of therapy compared to baseline in all cases reported. The added high concentration of CSF-CXCL13 plus CSF-TPHA reactivity above 1:40 titer agreed with the diagnosis of NS in 100% of the cases. Conclusion: In this case series, we present three cases of NS diagnosed using CXCL13 in CSF as a complementary test. These case series suggest that the clinical use of CSF-CXCL13 is useful as a supplementary biomarker for NS and for monitoring the effectiveness of NS therapy, especially in patients with nonreactive CSF-VDRL, excluding other neurologic diseases