Background: Renal cell carcinoma (RCC) represents the most common form of invasive kidney cancer in adults. Among the components critical to cellular regulation is Phospholipase C Beta 2 (PLCB2), a member of the phospholipase C enzyme family. This enzyme plays a vital role in managing key cellular functions such as growth, differentiation, migration, and survival. Despite its significant importance, the specific expression patterns and molecular mechanisms of PLCB2 in the progression of RCC are not well understood. Methods: This investigation employed a combination of bioinformatics analyses, scRNA-seq, functional assays, transcriptome sequencing, real-time quantitative PCR (RT-PCR), immunofluorescence, rescue experiments, and Western blotting to explore the regulatory function of PLCB2 in driving the epithelial-mesenchymal transition (EMT) in RCC through the PI3K/AKT signaling pathway. Results:PLCB2 expression is significantly elevated in RCC samples, and this increase is inversely correlated with patient prognosis. The knockdown of PLCB2 in RCC cell lines leads to a marked reduction in cell proliferation, invasion, migration, and EMT. Transcriptome sequencing further revealed that PLCB2 is significantly associated with the PI3K/AKT pathway. Notably, the PI3K activator 740Y-P was able to reverse the reductions in migration, invasion, and EMT caused by the PLCB2 knockdown. Conclusions: Our findings underscore the pivotal role of PLCB2 in regulating RCC invasion and metastasis by modulating the EMT via the PI3K/AKT signaling pathway. This highlights PLCB2 not only as a key prognostic biomarker, but also as a promising therapeutic target in the treatment of advanced-stage RCC, offering new avenues for more effective interventions.

Background Protein palmitoylation is an important post-translational modification involved in tumor progression, but its role in kidney renal clear cell carcinoma (KIRC) remains insufficiently understood. This study aimed to identify oncogenic ZDHHC family members in KIRC and clarify the biological significance of their downstream regulatory network. 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 cell-derived allograft 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-dependent palmitoylation of FOXA2 at C247 was required for FOXA2 binding to the CP promoter and for CP transactivation, as directly demonstrated by ChIP-qPCR and CP-promoter luciferase reporter assays using wild-type and palmitoylation-deficient (C247A) FOXA2. 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 may act as an oncogenic palmitoyltransferase in KIRC and could promote tumor progression by regulating the FOXA2-CP axis, copper homeostasis, and pro-angiogenic microenvironment remodeling. Targeting this pathway may represent a potential strategy warranting further preclinical validation for combination therapy in KIRC. Graphical Abstract