Palmitoyltransferase ZDHHC8 drives clear cell renal cell carcinoma progression by regulating the FOXA2–ceruloplasmin axis and tumor angiogenic microenvironment

Methods

Transcriptomic and clinical data from TCGA, GEO, ArrayExpress, and ICGC cohorts were integrated to evaluate the expression and prognostic relevance of ZDHHC family genes in KIRC. Candidate downstream targets were screened through intersection analyses. Single-cell RNA sequencing and spatial transcriptomics were used to determine the cellular distribution and spatial localization of key molecules.

CellChat and PySCENIC analyses were performed to infer intercellular communication patterns and upstream transcriptional regulation. Functional validation was conducted using qPCR, Western blotting, ELISA, ABE assay, proliferation and migration assays, intracellular metal ion detection, and xenograft experiments.Results:ZDHHC8, ZDHHC11, ZDHHC16, ZDHHC18, and ZDHHC22 were upregulated in KIRC and associated with poor prognosis.

Among their potential downstream effectors, ceruloplasmin (CP) showed the most consistent oncogenic relevance, and its regulation was strongest for ZDHHC8. ZDHHC8 and CP were coordinately elevated in KIRC tissues and cells, while pharmacological inhibition of palmitoylation or ZDHHC8 silencing reduced CP expression and secretion. Single-cell and spatial transcriptomic analyses showed that CP-high expression was enriched in a specific malignant epithelial subpopulation and co-localized with ZDHHC8 in tumor niches.

CellChat analysis revealed enhanced pro-angiogenic signaling from CP-high malignant cells to endothelial cells. Mechanistically, ZDHHC8 may regulate CP transcription through FOXA2 palmitoylation. Functionally, silencing ZDHHC8 or CP suppressed tumor cell proliferation and migration, altered intracellular Fe²⁺ and Cu⁺ homeostasis, and enhanced the antitumor efficacy of sunitinib in vivo.Conclusions:ZDHHC8 acts as a critical oncogenic palmitoyltransferase in KIRC and may promote tumor progression by regulating the FOXA2-CP axis, copper homeostasis, and pro-angiogenic microenvironment remodeling.

Targeting this pathway may provide a promising strategy for combination therapy in KIRC.