Zhou Zheng, Liu Qian, Zhang Gehou, Mohammed Diab, Amadou Sani, Tan Guolin, Zhang Xiaowei
Department of Otolaryngology Head & Neck, Third Xiangya Hospital, Changsha 410013, China.
Department of Otolaryngology Head & Neck, Xiangya Hospital, Changsha 410008, China.
Cancers (Basel). 2022 Jul 29;14(15):3694. doi: 10.3390/cancers14153694.
The metastatic characteristics of hypopharyngeal squamous cell carcinoma (HSCC) lead to many diagnostic and therapeutic challenges, while functional long non-coding RNAs (lncRNAs) can provide effective strategies for its diagnosis and treatment.
RT-qPCR, Western blot, immunohistochemistry, and an immunofluorescence assay were used to detect the related gene expression. Flow cytometry was used to measure the percentage of CD8 and CD4 T cells. CCK-8 and transwell assays were performed to analyze the role of HOXA11-AS1. The targeted relationship of the FOSL1/PD-L1 promoter was measured by ChIP and dual-luciferase reporter assays. RNA pulldown and RIP assays were used to measure the interaction between HOXA11-AS1, FOSL1, and PTBP1. A tumor xenograft study was used to analyze HOXA11-AS1 function in vivo.
HOXA11-AS1, PD-L1, and FOSL1 were upregulated in HSCC, and HOXA11-AS1 positively correlated with PD-L1. HOXA11-AS1 knockdown upregulated CD8 T cells through an increase in IFN-γ concentration while decreasing the proliferation, migration, and invasion of HSCC cells. FOSL1 bound the PD-L1 promoter, increasing gene expression. HOXA11-AS1 enhanced the stability of FOSL1 mRNA by binding to PTBP1. HOXA11-AS1 or PTBP1 overexpression increased FOSL1 and PD-L1 expression. PD-L1 knockdown arrested the inhibiting function of HOXA11-AS1 overexpression on CD8 T cell content. HOXA11-AS1 knockdown inhibited immune escape and metastasis through PD-L1 regulation by downregulating FOSL1 in vivo.
HOXA11-AS1 promoted PD-L1 expression by upregulating FOSL1 levels through PTBP1, thereby facilitating immune escape, proliferation, and metastasis of HSCC cells.
下咽鳞状细胞癌（HSCC）的转移特性带来了诸多诊断和治疗挑战，而功能性长链非编码RNA（lncRNAs）可为其诊断和治疗提供有效策略。
采用逆转录定量聚合酶链反应（RT-qPCR）、蛋白质免疫印迹法、免疫组织化学和免疫荧光分析检测相关基因表达。运用流式细胞术测定CD8和CD4 T细胞的百分比。进行细胞计数试剂盒-8（CCK-8）和Transwell实验以分析HOXA11-AS1的作用。通过染色质免疫沉淀（ChIP）和双荧光素酶报告基因实验测定FOSL1/PD-L1启动子的靶向关系。采用RNA下拉和RNA免疫沉淀实验测定HOXA11-AS1、FOSL1和多聚嘧啶结合蛋白1（PTBP1）之间的相互作用。通过肿瘤异种移植研究分析HOXA11-AS1在体内的功能。
HOXA11-AS1、程序性死亡受体配体1（PD-L1）和FOSL1在HSCC中表达上调，且HOXA11-AS1与PD-L1呈正相关。敲低HOXA11-AS1通过增加γ-干扰素（IFN-γ）浓度上调CD8 T细胞，同时降低HSCC细胞的增殖、迁移和侵袭能力。FOSL1与PD-L1启动子结合，增加基因表达。HOXA11-AS1通过与PTBP1结合增强FOSL1 mRNA的稳定性。HOXA11-AS1或PTBP1过表达增加FOSL1和PD-L1表达。敲低PD-L1可阻止HOXA11-AS1过表达对CD8 T细胞含量的抑制作用。在体内，敲低HOXA11-AS1通过下调FOSL1调控PD-L1，从而抑制免疫逃逸和转移。
HOXA11-AS1通过PTBP1上调FOSL1水平，促进PD-L1表达，从而促进HSCC细胞的免疫逃逸、增殖和转移。
