BackgroundChemokine (C-X-C motif) ligand 13 (CXCL13) was known as a selective chemotaxis for B cells, a product of follicular helper CD4+T cells (TFH) and a contributor to tertiary lymphoid structures (TLS). Although secretion and function of CXCL13 produced by TFH have been deeply explored, the immune function and prognostic significance of CXCL13 secreted by CD8+T cells still remain unrevealed. This study aims to investigate the clinical merit of CXCL13+CD8+T cells in clear cell renal cell carcinoma (ccRCC).MethodsWe analyzed prognostic value and immune contexture that associated with CXCL13+CD8+T cells infiltration level in a total of 755 patients from Zhongshan Hospital cohort (n=223) and The Cancer Genome Atlas cohort (n=532). In vitro analyses were conducted on 42 samples of resected tumor tissue from Zhongshan Hospital in order to detect the immune status of CXCL13+CD8+T cells and total CD8+T cells. Immunohistochemistry (IHC) and flow cytometry were applied to characterize immune cells and portray the tumor microenvironment (TME) in ccRCC.ResultsIntratumoral CXCL13+CD8+T cells abundance was associated with inferior overall survival and disease-free survival. CXCL13+CD8+T cells possessed higher level of immune checkpoints like programmed cell-death protein 1 (PD-1), T-cell immunoglobulin mucin 3 (Tim-3), T cell immunoreceptor with Ig and ITIM domains (TIGIT) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), higher Ki-67 expression and lower tumor necrosis factor α (TNF-α), interferon γ (IFN-γ) expression. Total CD8+T cells in high-level CXCL13+CD8+T cells infiltration subgroup exhibited elevated exhausted markers (PD-1, Tim-3, TIGIT) and descended activated markers (TNF-α, IFN-γ) without quantity variance. Furthermore, the abundance of intratumoral CXCL13+CD8+T cell was correlated with immunoevasive TME accompanied by increased T helper 2 cells, tumor-associated macrophages, Foxp3+ regulatory T cells, TLS and decreased natural killer cells, GZMB+ cells.ConclusionsIntratumoral CXCL13+CD8+T cells infiltration indicated inferior clinical outcome in patients with ccRCC. CXCL13+CD8+T cells possessed increased exhausted markers, decreased effector molecules and better proliferation ability. CXCL13+CD8+T cells abundance impaired total CD8+T cells’ immune function. Intratumoral CXCL13+CD8+T cells abundance was associated with immunoevasive contexture. The abundance of CXCL13+CD8+T cells was an independent prognosticator and a potential immunotherapeutic target marker for ccRCC treatment.

BackgroundT-cell immunoglobulin and ITIM domain (TIGIT) is identified as a novel checkpoint receptor that can facilitate immune escape via mediating T-cell exhaustion in tumors. However, the clinical significance and immune contexture correlation of intratumoral TIGIT+ CD8+ T-cells remain to be further explored in muscle-invasive bladder cancer (MIBC).Methods259 patients with MIBC from two clinical centers (Zhongshan Hospital, n=141; Shanghai Cancer Center, n=118) were analyzed to evaluate the prognostic value and immune contexture association of TIGIT+ CD8+ T-cells through immunohistochemistry. Fresh tumor tissue samples from 26 patients with MIBC were examined to discover the phenotype of this CD8 subpopulation by flow cytometry.ResultsHigh infiltration of intratumoral TIGIT+ CD8+ T-cells predicted poor overall survival (OS) and recurrence-free survival (RFS) in MIBC. For patients with stage II MIBC with low infiltration of TIGIT+ CD8+ cells, adjuvant chemotherapy (ACT) could significantly prolong their OS and RFS. Intratumoral TIGIT+ CD8+ T-cell abundance was correlated with impaired CD8+ T-cell cytotoxicity and exhibited production of immunosuppressive cytokine IL-10. Further analysis of tumor-infiltrating immune cell landscape revealed TIGIT+ CD8+ T-cells were associated with suppressive immune contexture, including Th2 cells, regulatory T-cells, mast cells and neutrophils.ConclusionIntratumoral TIGIT+ CD8+ T-cell abundance could serve as an independent prognosticator for clinical outcome and a predictive biomarker for inferior ACT responsiveness. Intratumoral TIGIT+ CD8+ T-cell abundance correlated with dampened CD8+ T-cell antitumor immunity and immunosuppressive contexture abundance, highlighting a tumor-promoting role of TIGIT+ CD8+ T-cells.