This study aimed to investigate the T cell immunoreceptor with ITIM and Ig domains (TIGIT) expression in lung adenocarcinoma (LUAD). TIGIT expression was measured by western blot, reverse transcription quantitative polymerase chain reaction. Seventy-two paired surgical specimens were collected from patients with stage I-IV LUAD. The expression of TIGIT in surgical specimens was determined using immunohistochemistry. TIGIT was overexpressed in LUAD tissues. Moreover, overexpressed TIGIT was significantly associated with advanced clinical staging, lymph node metastasis, distant metastasis, and TP53 mutations in LUAD. Moreover, high expression of TIGIT was negatively correlated with purity of CD4⁺ T cells. High rations of TIGIT⁺CD4⁺ T cells predicted poor overall survival of LUAD patients. Additionally, high ratios of TIGIT⁺CD4⁺ T cells is closely related to CD4⁺ T cell depletion. Taken together, TIGIT was overexpressed in LUAD patients. High levels of TIGIT induced the alteration of CD4⁺ T cell based immunomodulation and predicted poor prognosis of LUAD patients. Therefore, TIGIT can be potential biomarker for LUAD.

中文翻译：

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TIGIT在肺腺癌中的异位表达及其临床意义

本研究旨在探讨具有 ITIM 和 Ig 结构域的 T 细胞免疫受体 (TIGIT) 在肺腺癌 (LUAD) 中的表达。通过蛋白质印迹、逆转录定量聚合酶链反应测量TIGIT表达。从 I-IV 期 LUAD 患者中收集了 72 对手术标本。使用免疫组织化学测定手术标本中 TIGIT 的表达。TIGIT 在 LUAD 组织中过表达。此外，过度表达的TIGIT与LUAD的晚期临床分期、淋巴结转移、远处转移和TP53突变显着相关。^{此外，TIGIT的高表达与CD4 +} T细胞的纯度呈负相关。高比例的 TIGIT ⁺ CD4 ⁺ T 细胞预示着 LUAD 患者总体生存率较差。此外，高比例的 TIGIT ⁺ CD4 ^{+ T 细胞与 CD4 +} T 细胞耗竭密切相关。总的来说，TIGIT 在 LUAD 患者中过度表达。高水平的 TIGIT 诱导基于 CD4 ⁺ T 细胞的免疫调节的改变，并预测 LUAD 患者的不良预后。因此，TIGIT 可以作为 LUAD 的潜在生物标志物。