Lactylation-related gene signature as a prognostic biomarker for neuroblastoma: insights into tumor progression and immune modulation.

BACKGROUND: Lactylation, a recently identified post-translational modification mediated by lactate, plays a critical role in regulating metabolic and immune processes in tumors. However, its function in neuroblastoma, particularly its association with tumor progression and immune modulation, remains unclear. METHOD: We conducted immunohistochemical analyses on neuroblastoma tissue samples to evaluate lactylation levels and their clinical relevance. Single-cell RNA sequencing data and the AUCell algorithm were utilized to identify lactylation-related genes (LRGs) and map their expression within the tumor microenvironment. A seven-gene LRGs-based prognostic model was constructed using Cox regression and Least absolute shrinkage and selection operator (LASSO) analysis and validated in independent datasets. Bioinformatics analyses were performed to assess the associations between LRGs and clinical characteristics, biological pathways, immune infiltration, and therapeutic response. Functional assays further investigated the role of KLHL32, a key gene identified in the model. RESULTS: Our study revealed significantly elevated lactylation levels in neuroblastoma tumor tissues, which were associated with advanced disease stages and poor prognoses. We identified 407 LRGs and developed a seven-gene prognostic model that effectively stratified patients by risk, showing robust predictive performance in both internal and external validations. High-risk patients exhibited increased activation of tumor-promoting pathways, including glycolysis and PI3K/AKT signaling, alongside reduced immune cell infiltration, indicative of an immunosuppressive tumor microenvironment. Among the LRGs, KLHL32 emerged as a key tumor suppressor, inhibiting neuroblastoma cell proliferation, migration, and invasion, while enhancing NK cell-mediated cytotoxicity and anti-GD2 immunotherapies response. KLHL32 overexpression suppressed lactate production by downregulating the PI3K/AKT pathway, reducing protein lactylation levels, and promoting anti-tumor immunity. CONCLUSION: Our findings establish lactylation as a critical determinant of neuroblastoma progression and prognosis. The seven-gene lactylation-related prognostic model provides a novel tool for patient stratification and therapeutic decision-making. Additionally, KLHL32 represents a promising target for enhancing immunotherapy efficacy by modulating metabolic and immune pathways, offering new opportunities for precision treatment in high-risk neuroblastoma patients.