Immunoregulatory Arginase-1 (Arg-1) is present in the tumor microenvironment of solid tumors. Its association to clinicopathology and its prognostic impact are inconsistent among different tumor types and biological fluids. This study evaluated Arg-1 protein levels in tumors and the circulation of patients with head and neck squamous cell carcinoma (HNSCC) in relation to clinical stage and prognosis. Tumor Arg-1 expression was monitored via immunohistochemistry while plasma Arg-1 levels via ELISA in 37 HNSCC patients. Arg-1 presence in plasma-derived exosomes was assessed using Western blots in 20 HNSCC patients. High tumor Arg-1 expression correlated with favorable clinicopathology and longer recurrence-free survival (RFS), while high plasma Arg-1 levels were associated with unfavorable clinicopathology. All patients with low tumor and high plasma Arg-1 had nodal metastases and developed recurrence. This discrepancy was attributed to the presence of Arg-1-carrying exosomes. Arg-1 was found in plasma-derived exosomes from all HNSCC patients. High exosomal Arg-1 levels were associated with positive lymph nodes and short RFS. Circulating Arg-1+exosomes represent a mechanism of active Arg-1 export from the tumor to the periphery. Exosomes reflected biologically relevant Arg-1 levels in metastatic HNSCC and emerged as potentially more accurate biomarkers of metastatic disease and RFS than tissue or plasma Arg-1 levels.
免疫调节性精氨酸酶-1（Arg-1）存在于实体肿瘤的微环境中。其与临床病理学的关联及预后影响在不同肿瘤类型和生物体液中存在差异。本研究评估了头颈部鳞状细胞癌（HNSCC）患者肿瘤组织及循环系统中Arg-1蛋白水平与临床分期及预后的关系。通过免疫组化检测37例HNSCC患者肿瘤组织Arg-1表达，采用ELISA法检测血浆Arg-1水平，并运用Western blot技术对20例HNSCC患者血浆来源外泌体进行Arg-1检测。结果显示：高肿瘤组织Arg-1表达与良好临床病理特征及较长无复发生存期（RFS）相关，而高血浆Arg-1水平则与不良临床病理特征相关。所有呈现低肿瘤组织表达伴高血浆水平的患者均发生淋巴结转移并出现复发。这种差异归因于携带Arg-1的外泌体存在——所有HNSCC患者血浆来源外泌体中均检测到Arg-1，且高外泌体Arg-1水平与淋巴结阳性及短RFS显著相关。循环Arg-1阳性外泌体构成了肿瘤向周围组织主动输出Arg-1的机制。在转移性HNSCC中，外泌体反映了具有生物学相关性的Arg-1水平，相较于组织或血浆Arg-1水平，外泌体可能成为更精准的转移性疾病及RFS生物标志物。
肿瘤(癌症)患者之家