Table2_Increased response to TPF chemotherapy promotes immune escape in hypopharyngeal squamous cell carcinoma.docx

Background: There is an urgent need to identify which patients would benefit from TPF chemotherapy in hypopharyngeal squamous cell carcinoma (HPSCC) and to explore new combinations to improve the treatment effect.
Materials and methods: Gene-expression profiles in 15 TPF-sensitive patients were compared to 13 resistant patients. Immunohistochemistry (IHC) was performed to detect CD8+ T cells in 28 samples. Patient-Derived Tumor Xenograft (PDX) model and IHC were used to verify markers that optimize treatment for HPSCC.
Results: Through RNA sequencing 188 genes were up-regulated in TPF chemotherapy-resistant (CR) tissues were involved in T cell activation, while 60 down-regulated genes were involved in glycolysis. Gene set enrichment analysis (GSEA) showed that chemotherapy-sensitive (CS) group upregulation of the pathways of glycolysis, while immune response was downregulated. CIBERSORT, MCP-counter, and IHC proved that most immune cells including CD8+ T cells in the CR significantly higher than that in CS group. Among the 16 up-regulated genes in CS had close associations, the most significant negative correlation between the gene level and CD8+ T cells existed in SEC61G. SEC61G was related to glycolysis, which was transcriptionally regulated by E2F1, and participated in antigen degradation through ubiquitin-dependent protein catabolic process. Palbociclib, combined with Cetuximab decreased the tumor burden and significantly suppressed the expression of E2F1 and SEC61G while activating MHC-I in PDX model.
Conclusion: Enhanced glycolysis promoted immune escape, but increased response to TPF chemotherapy. SEC61G was the center of the molecular network and targeting the E2F1/SEC61G pathway increased the expression level of MHC-I.

背景：目前亟需明确哪些喉鳞状细胞癌（hypopharyngeal squamous cell carcinoma, HPSCC）患者可从TPF化疗中获益，并探索新型联合治疗方案以提升治疗效果。
材料与方法：将15例TPF化疗敏感患者的基因表达谱与13例耐药患者进行对比。采用免疫组化（Immunohistochemistry, IHC）检测28份样本中的CD8+ T细胞。通过患者来源异种移植模型（Patient-Derived Tumor Xenograft, PDX）结合免疫组化，验证可优化喉鳞状细胞癌治疗方案的潜在标志物。
结果：经RNA测序发现，TPF化疗耐药（chemotherapy-resistant, CR）组织中上调的188个基因参与T细胞活化过程，而下调的60个基因则与糖酵解相关。基因集富集分析（Gene Set Enrichment Analysis, GSEA）结果显示，化疗敏感（chemotherapy-sensitive, CS）组的糖酵解通路显著上调，而免疫应答通路则呈下调趋势。通过CIBERSORT、MCP-counter及免疫组化分析证实，耐药组中包括CD8+ T细胞在内的多数免疫细胞浸润水平显著高于敏感组。在化疗敏感组上调的16个基因中，SEC61G的表达水平与CD8+ T细胞数量呈最显著的负相关。SEC61G与糖酵解过程密切相关，其转录受E2F1调控，并通过泛素依赖性蛋白分解途径参与抗原降解。在PDX模型中，帕博西尼（Palbociclib）联合西妥昔单抗（Cetuximab）可降低肿瘤负荷，显著抑制E2F1与SEC61G的表达，同时激活MHC-I通路。
结论：增强的糖酵解可促进肿瘤免疫逃逸，但可提升机体对TPF化疗的响应性。SEC61G是该分子网络的核心节点，靶向E2F1/SEC61G通路可上调MHC-I的表达水平。