Department of Respiratory Medicine, The Affiliated Huadong Hospital of Fudan University, Shanghai, China.
Department of Thoracic Surgery, The Affiliated Huadong Hospital of Fudan University, Shanghai, China.
Cancer Res Treat. 2020 Jul;52(3):867-885. doi: 10.4143/crt.2019.606. Epub 2020 Mar 11.
Caspase recruitment domain containing protein 9 (CARD9) has been demonstrated to be a pro-tumor factor in various cancers. However, our previous study found a significant decrease of CARD9 in malignant pleural effusion compared with benign pleural effusion. So we investigated the role of CARD9 in non-small cell lung cancer (NSCLC) and its working mechanism.
Immunohistochemistry, western blot, and quantitative real-time polymerase chain reaction were used to detect the expression of CARD9 in specimens of NSCLC patients. The Cancer Genome Atlas (TCGA) databasewas also used to analyze the expression of CARD9 in NSCLC and its predicting value for prognosis. Immunofluorescence was used for CARD9 cellular location. Cell growth assay, clonal formation assay, wound healing assay, matrigel invasion assay, and flow cytometry were used to test cell proliferation, migration, invasion, apoptosis, and cycle progression of NSCLC cells with CARD9 knockdown or CARD9 overexpression. Co-immunoprecipitation was used to identify the interaction between CARD9 and B-cell lymphoma 10 (BCL10). SB203580 was used to inhibit p38 activation.
CARD9 was decreased in NSCLC tissues compared with normal tissues; low CARD9 expression was associated with poor survival. CARD9 was expressed both in tumor cells and macrophages. Downregulation of CARD9 in NSCLC cells enhanced the abilities of proliferation, invasion and migration via activated MAPK/p38 signaling, while overexpression of CARD9 presented antitumor effects. BCL10 was identified to interact with CARD9.
We demonstrate that CARD9 is an independent prognostic factor in NSCLC patients and inhibits proliferation, migration, and invasion by suppressing MAPK/p38 pathway in NSCLC cells.
半胱氨酸天冬氨酸蛋白酶募集域蛋白 9（CARD9）已被证明在多种癌症中是一种促肿瘤因子。然而，我们之前的研究发现恶性胸腔积液中 CARD9 的含量明显低于良性胸腔积液。因此，我们研究了 CARD9 在非小细胞肺癌（NSCLC）中的作用及其作用机制。
免疫组织化学、western blot 和定量实时聚合酶链反应用于检测 NSCLC 患者标本中 CARD9 的表达。还使用癌症基因组图谱（TCGA）数据库分析 CARD9 在 NSCLC 中的表达及其对预后的预测价值。免疫荧光用于 CARD9 细胞定位。细胞生长试验、克隆形成试验、划痕愈合试验、基质胶侵袭试验和流式细胞术用于检测 CARD9 敲低或 CARD9 过表达的 NSCLC 细胞的增殖、迁移、侵袭、凋亡和细胞周期进展。免疫共沉淀用于鉴定 CARD9 与 B 细胞淋巴瘤 10（BCL10）之间的相互作用。SB203580 用于抑制 p38 激活。
与正常组织相比，CARD9 在 NSCLC 组织中减少；低 CARD9 表达与预后不良相关。CARD9 在肿瘤细胞和巨噬细胞中均有表达。在 NSCLC 细胞中下调 CARD9 通过激活 MAPK/p38 信号通路增强了增殖、侵袭和迁移能力，而过表达 CARD9 则呈现抗肿瘤作用。鉴定出 BCL10 与 CARD9 相互作用。
我们证明 CARD9 是 NSCLC 患者的独立预后因素，并通过抑制 NSCLC 细胞中的 MAPK/p38 通路抑制增殖、迁移和侵袭。
