PO.MCB07.04 · 分子与细胞生物学
DPF3a-YY1协同作用通过激活CSF2转录驱动肾细胞癌的免疫抑制
DPF3a-YY1 cooperation drivesimmunosuppression in renal cell carcinoma by activating CSF2 transcription
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
背景：肾细胞癌（RCC）是最具侵袭性和治疗抵抗性的恶性肿瘤之一，其特征为广泛的血管生成和显著的免疫逃逸。全基因组关联研究已鉴定出SNP rs4903064是调控DPF3a表达的关键变异，DPF3a是一种在RCC中与HIF信号通路相互作用的染色质重塑因子。尽管DPF3基因编码两种异构体（DPF3a和DPF3b），但DPF3a在RCC发生和进展中的生物学意义在很大程度上仍未被探究。
方法：采用Western印迹（WB）、定量PCR（qPCR）和免疫组织化学（IHC）检测DPF3各异构体在RCC细胞系和临床肿瘤标本中的表达。应用整合RNA-seq、CUT&Tag和ATAC-seq的多组学方法界定DPF3a依赖的转录及染色质可及性图谱。采用基于TurboID的邻近标记实验鉴定DPF3a的相互作用蛋白，并通过共免疫沉淀（Co-IP）验证这些相互作用。采用单细胞RNA测序（scRNA-seq）和流式细胞术评估DPF3a对肿瘤免疫微环境的影响。
结果：本研究发现，DPF3a（而非DPF3b）在RCC组织和细胞系中显著过表达。整合多组学分析显示，DPF3a结合CSF2基因启动子并促进其转录激活，从而导致CSF2分泌增加。机制上，DPF3a的PHD1/2结构域介导其与转录因子YY1的相互作用，二者协同促进CSF2转录。此外，单细胞RNA测序分析表明，DPF3a驱动的CSF2上调促进中性粒细胞浸润和CD8⁺ T细胞耗竭，从而抑制抗肿瘤免疫。
结论：我们的研究结果将DPF3a鉴定为RCC中一种此前未被认识的致癌异构体。通过与YY1形成复合物并激活CSF2转录，DPF3a驱动中性粒细胞募集和CD8⁺ T细胞耗竭，从而营造免疫抑制微环境并促进RCC进展。
关键词：DPF3a；YY1；CSF2；肾细胞癌；肿瘤免疫微环境
查看英文原文 English abstract
Background: Renal cell carcinoma (RCC) is among the most aggressive and therapy-resistant malignancies, characterized by extensive vascularization and profound immune evasion. Genome-wide association studies have identified the SNP rs4903064 as a key variant regulating the expression of DPF3a, a chromatin remodeling factor that interacts with HIF signaling in RCC. Although the DPF3 gene encodes two isoforms (DPF3a and DPF3b), the biological significance of DPF3a in RCC initiation and progression remains largely unexplored.
Methods: The expression of DPF3 isoforms in RCC cell lines and clinical tumor specimens was examined by Western blotting (WB), quantitative PCR (qPCR), and immunohistochemistry (IHC). Multi-omics approach integrating RNA-seq, CUT&Tag, and ATAC-seq were applied to define DPF3a-dependent transcriptional and chromatin accessibility landscapes. TurboID-based proximity labeling assays were used to identify interactors of DPF3a,and co-immunoprecipitation (Co-IP) were performed to validate these interactions. Single-cell RNA sequencing (scRNA-seq) and flow cytometry were used to evaluate the impact of DPF3a on the tumor immune microenvironment.
Results: In this study, we found DPF3a, but not DPF3b, was markedly overexpressed in RCC tissues and cell lines. Integrated multi-omics analysis revealed that DPF3a binds to the promoter of the CSF2 gene and promotes its transcriptional activation, consequently leading to increased CSF2 secretion. Mechanistically, the PHD1/2 domains of DPF3a mediate its interaction with the transcription factor YY1, which collaboratively facilitates CSF2 transcription. Furthermore, single-cell RNA sequencing analysis indicated that DPF3a-driven CSF2 upregulation promotes neutrophil infiltration and CD8⁺ T-cell exhaustion, thereby contributing to the suppression of anti-tumor immunity.
Conclusions: Our findings identify DPF3a as a previously unrecognized oncogenic isoform in RCC. By forming a complex with YY1 and activating CSF2 transcription, DPF3a drives neutrophil recruitment and CD8⁺ T-cell exhaustion, thereby fostering an immunosuppressive microenvironment and promoting RCC progression.
Keywords: DPF3a; YY1; CSF2; Renal Cell Carcinoma; Tumor Immune Microenvironment
利益披露 Disclosure
X. Yu, None..
H. Liu, None..
Z. Mi, None..
K. Chen, None.