HHLA2-KCTD12轴：调控喉鳞状细胞癌生物学功能的潜在机制

文献信息

中文摘要

背景： 越来越多的证据表明，HHLA2的异常表达不仅与肿瘤发生、疾病进展和转移扩散密切相关，还参与肿瘤免疫微环境的复杂调控。然而，HHLA2在喉鳞状细胞癌（LSCC）中的生物学功能及其作用的分子机制仍未被探索。
材料与方法： 采用多重免疫荧光（mIHC）系统评估LSCC肿瘤标本及配对癌旁组织中HHLA2的表达。通过一系列体外实验评估HHLA2沉默对LSCC细胞的功能影响，包括基于CCK-8的增殖分析、伤口愈合（划痕）实验和侵袭实验。随后整合转录组测序与公共数据库挖掘，以鉴定可能受HHLA2调控、参与LSCC生物学行为的关键靶基因。此外，进行基因本体（GO）、京都基因与基因组百科全书（KEGG）和基因集富集分析（GSEA）通路分析，以描绘HHLA2在LSCC中可能发挥调控作用的信号网络和分子通路。
结果： HHLA2在LSCC肿瘤组织中表达显著升高，并与患者不良预后相关。功能实验显示，抑制HHLA2可显著抑制LSCC细胞增殖、迁移和侵袭，凸显其在维持恶性表型中的重要作用。机制上，我们鉴定出钾通道四聚化结构域12（KCTD12）是HHLA2介导这些致癌过程的关键靶点。重要的是，强制过表达KCTD12可有效抵消HHLA2耗竭所诱导的抑制作用，从而恢复LSCC细胞的增殖、迁移和侵袭潜能。此外，通路富集分析表明，TNF-NF-κB信号通路可能是HHLA2协调肿瘤细胞功能和免疫调节机制的关键通道。HHLA2-KCTD12轴可能通过TNF-NF-κB信号通路调控LSCC细胞表型并重塑肿瘤免疫微环境。
结论： HHLA2增强LSCC细胞的增殖、迁移和侵袭能力，并可能通过HHLA2-KCTD12轴调控TNF-NF-κB信号通路，从而促进免疫微环境重塑。

英文摘要

BACKGROUND: Accumulating evidence suggests that aberrant HHLA2 expression is closely implicated not only in tumorigenesis, disease progression, and metastatic spread, but also in the intricate modulation of the tumor immune microenvironment. Nevertheless, the biological functions of HHLA2 and the molecular mechanisms underlying its action in laryngeal squamous cell carcinoma (LSCC) remain unexplored.
MATERIALS AND METHODS: HHLA2 expression was systematically assessed in LSCC tumor specimens and matched adjacent tissues using multiplex immunofluorescence (mIHC). The functional consequences of HHLA2 silencing in LSCC cells were evaluated through a series of in vitro assays, including CCK-8-based proliferation analysis, wound-healing (scratch) assays, and invasion assays. Transcriptomic sequencing integrated with public database mining was subsequently performed to identify key target genes potentially governed by HHLA2 in regulating LSCC biological behavior. Furthermore, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Set Enrichment Analysis (GSEA) pathway analyses were conducted to delineate the signaling networks and molecular pathways through which HHLA2 might exert its regulatory effects in LSCC.
RESULTS: HHLA2 expression was significantly elevated in LSCC tumor tissues, and associated with poor prognosis in patients. Functional experiments revealed that suppression of HHLA2 leads to marked inhibition of LSCC cell proliferation, migration, and invasion, underscoring its essential role in sustaining malignant phenotypes. Mechanistically, we identified potassium channel tetrameric domain 12 (KCTD12) as a pivotal target of HHLA2 in mediating these oncogenic processes. Importantly, forced overexpression of KCTD12 effectively counterbalanced the inhibitory effects induced by HHLA2 depletion, thereby restoring proliferative, migratory, and invasive potential to LSCC cells. Furthermore, pathway enrichment analyses indicated that the TNF-NF-κB signalling pathway might serve as a key conduit through which HHLA2 orchestrated both tumor cell functions and immune regulatory mechanisms. The HHLA2-KCTD12 axis may regulate the phenotype of LSCC cells and reshape the tumor immune microenvironment through the TNF-NF-κB signaling pathway.
CONCLUSIONS: HHLA2 enhanced the proliferative, migratory, and invasive capacities of LSCC cells and might contribute to immune microenvironment remodeling via modulation of TNF-NF-κB signaling through the HHLA2-KCTD12 axis.