Department of Urology, Zhongshan Hospital, Fudan University, Shanghai, China.
Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China.
J Immunother Cancer. 2021 Feb;9(2). doi: 10.1136/jitc-2020-001823.
Chemokine (C-X-C motif) ligand 13 (CXCL13) was known as a selective chemotaxis for B cells, a product of follicular helper CD4T cells (T) and a contributor to tertiary lymphoid structures (TLS). Although secretion and function of CXCL13 produced by T have been deeply explored, the immune function and prognostic significance of CXCL13 secreted by CD8T cells still remain unrevealed. This study aims to investigate the clinical merit of CXCL13CD8T cells in clear cell renal cell carcinoma (ccRCC).
We analyzed prognostic value and immune contexture that associated with CXCL13CD8T 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 CXCL13CD8T cells and total CD8T cells. Immunohistochemistry (IHC) and flow cytometry were applied to characterize immune cells and portray the tumor microenvironment (TME) in ccRCC.
Intratumoral CXCL13CD8T cells abundance was associated with inferior overall survival and disease-free survival. CXCL13CD8T 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 CD8T cells in high-level CXCL13CD8T 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 CXCL13CD8T 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.
Intratumoral CXCL13CD8T cells infiltration indicated inferior clinical outcome in patients with ccRCC. CXCL13CD8T cells possessed increased exhausted markers, decreased effector molecules and better proliferation ability. CXCL13CD8T cells abundance impaired total CD8T cells' immune function. Intratumoral CXCL13CD8T cells abundance was associated with immunoevasive contexture. The abundance of CXCL13CD8T cells was an independent prognosticator and a potential immunotherapeutic target marker for ccRCC treatment.
趋化因子（C-X-C 基序）配体 13（CXCL13）是一种选择性趋化因子，可吸引 B 细胞，由滤泡辅助 CD4T 细胞（T 细胞）产生，并有助于三级淋巴结构（TLS）的形成。虽然 T 细胞产生的 CXCL13 的分泌和功能已经得到深入研究，但 CD8T 细胞分泌的 CXCL13 的免疫功能和预后意义仍未被揭示。本研究旨在探讨 CXCL13CD8T 细胞在透明细胞肾细胞癌（ccRCC）中的临床价值。
我们分析了来自中山医院队列（n=223）和癌症基因组图谱队列（n=532）的共 755 名患者的预后价值和与 CXCL13CD8T 细胞浸润水平相关的免疫结构。我们对中山医院 42 个切除肿瘤组织样本进行了体外分析，以检测 CXCL13CD8T 细胞和总 CD8T 细胞的免疫状态。免疫组织化学（IHC）和流式细胞术用于描绘 ccRCC 中的免疫细胞和肿瘤微环境（TME）。
肿瘤内 CXCL13CD8T 细胞丰度与总生存率和无病生存率降低相关。CXCL13CD8T 细胞表达更高水平的免疫检查点，如程序性死亡蛋白 1（PD-1）、T 细胞免疫球蛋白粘蛋白 3（Tim-3）、T 细胞免疫受体 Ig 和 ITIM 结构域（TIGIT）和细胞毒性 T 淋巴细胞相关蛋白 4（CTLA-4），Ki-67 表达更高，肿瘤坏死因子-α（TNF-α）和干扰素-γ（IFN-γ）表达更低。高水平 CXCL13CD8T 细胞浸润亚组中的总 CD8T 细胞表达更高的耗竭标志物（PD-1、Tim-3、TIGIT）和更低的激活标志物（TNF-α、IFN-γ），而细胞数量没有变化。此外，肿瘤内 CXCL13CD8T 细胞的丰度与免疫逃避的 TME 相关，伴有辅助性 T 细胞 2（Th2）细胞、肿瘤相关巨噬细胞、Foxp3 调节性 T 细胞、TLS 增加，自然杀伤细胞、GZMB 细胞减少。
肿瘤内 CXCL13CD8T 细胞浸润与 ccRCC 患者的临床预后不良相关。CXCL13CD8T 细胞具有更高的耗竭标志物表达，更低的效应分子表达和更好的增殖能力。肿瘤内 CXCL13CD8T 细胞的丰度损害了总 CD8T 细胞的免疫功能。肿瘤内 CXCL13CD8T 细胞的丰度与免疫逃避结构有关。CXCL13CD8T 细胞的丰度是 ccRCC 治疗的独立预后因素和潜在的免疫治疗靶点标志物。
