Pan Yinglian, Yin Qiushi, Wang Zhaoliang, Wu Gang, Liu Kun, Li Xiaowei, Liu Jinchen, Zeng Jiangzheng, Lin Bo, Li Wei, Zhu Mingyue, Li Mengsen
Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical University, Haikou, Hainan Province, PR China; Department of Medical Oncology, the First Affiliated Hospital of Hainan Medical University, Haikou, Hainan Province, PR China.
Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical University, Haikou, Hainan Province, PR China.
Transl Oncol. 2025 Feb;52:102240. doi: 10.1016/j.tranon.2024.102240. Epub 2024 Dec 11.
Alpha fetoprotein(AFP) overexpression connecting with macrophage dysfunction remain poorly defined. In this study, explore AFP regulates macrophage immunomodulation in hepatocellular carcinoma(HCC) through comprehensive in vitro and in vivo studies.
Immunohistochemical and immunofluorescence staining was used to analyze the relativity of AFP and cellular membrane CD47 expression in clinical 30 HCC tissues, and the expression of AFP and CD47 in HCC cells. The intelligent living-cell high-throughput imaging analyzer was applied to dynamically track and image of macrophages to phagocytize HCC cells. The effect of AFP on regulating the level of CD47 in cellular membrane and growth of tumor in vivo was performed by animal experiment. The association of AFP and CD47 in HCC cells was detected by single cell analysis.
The present results indicated that AFP upregulated the localization of CD47 on the HCC cell surface. CD47 overexpression stimulates HCC to escape immune surveillance by transmitting "don't eat me" signals to macrophages, lead to inhibit macrophage to phagocytize HCC cells. Mechanistically, the results demonstrated that AFP enhanced CD47 membrane translocation by interacting with Hu-Antigen R(HuR), an RNA-binding protein that regulates mRNA stability and translation. AFP alters the subcellular distribution of HuR, increasing its cytoplasmic accumulation and binding to CD47 transcript.
AFP enhanced CD47 membrane translocation by interacting with HuR. These findings proved that AFP could inhibit macrophage to phagocytize HCC cells by upregulating the localization of CD47 on the HCC cell surface. Combination of AFP with CD47 blockade may be a potential therapeutic strategy for HCC treatment.
甲胎蛋白（AFP）过表达与巨噬细胞功能障碍之间的联系仍不清楚。本研究通过全面的体外和体内研究，探索AFP在肝细胞癌（HCC）中对巨噬细胞免疫调节的作用。
采用免疫组织化学和免疫荧光染色分析30例临床肝癌组织中AFP与细胞膜CD47表达的相关性，以及肝癌细胞中AFP和CD47的表达。应用智能活细胞高通量成像分析仪动态跟踪巨噬细胞吞噬肝癌细胞的过程并成像。通过动物实验研究AFP对调节细胞膜CD47水平和体内肿瘤生长的影响。采用单细胞分析检测肝癌细胞中AFP与CD47的关联。
目前的结果表明，AFP上调了CD47在肝癌细胞表面的定位。CD47过表达通过向巨噬细胞传递“别吃我”信号刺激肝癌逃避免疫监视，导致巨噬细胞吞噬肝癌细胞的能力受到抑制。机制上，结果表明AFP通过与Hu抗原R（HuR）相互作用增强了CD47的膜转运，HuR是一种调节mRNA稳定性和翻译的RNA结合蛋白。AFP改变了HuR的亚细胞分布，增加了其在细胞质中的积累并与CD47转录本结合。
AFP通过与HuR相互作用增强了CD47的膜转运。这些发现证明，AFP可通过上调CD47在肝癌细胞表面的定位来抑制巨噬细胞吞噬肝癌细胞。AFP与CD47阻断剂联合使用可能是肝癌治疗的一种潜在策略。
