Identifying the role of MTHFD1L in prostate cancer progression from genetic analysis and experimental validation
One-carbon metabolism plays a crucial role in tumorigenesis as it supplies the one-carbon units necessary for nucleotide synthesis, epigenetic regulation, and redox metabolism, ensuring the rapid proliferation of cancer cells. However, their roles in prostate cancer progression remain poorly understood. In this study, we investigated the association between genetic variants in the one-carbon metabolism pathway and clinical outcomes in patients receiving androgen deprivation therapy for prostate cancer. The associations of 130 single-nucleotide polymorphisms located within 14 genes involved in the one-carbon metabolism pathway with cancer-specific survival (CSS), overall survival, and progression-free survival were assessed using Cox regression in 630 patients with prostate cancer. Subsequently, functional studies were performed using prostate cancer cell lines. After adjusting for covariates and multiple testing, MTHFD1L rs2073190 was found to be significantly associated with CSS (P = 0.000184). Further pooled analysis of multiple datasets demonstrated that MTHFD1L was upregulated in prostate cancer and increased MTHFD1L expression was positively correlated with tumor aggressiveness and poor patient prognosis. Functionally, MTHFD1L knockdown suppressed prostate cancer cell proliferation and colony formation. RNA sequencing and pathway analysis revealed that differentially expressed genes were predominantly enriched in the cell cycle pathway. In conclusion, genetic variants in MTHFD1L of one-carbon metabolism may serve as promising predictors, and our findings offer valuable insights into the underlying genetic mechanisms of prostate cancer progression. Overall design: To investigate the biological function of MTHFD1L, we employed an siRNA-based approach to reduce its expression in PC-3 and C4-2 human prostate cancer cell lines. Comparative gene expression profiling RNA-seq analysis was conducted for PC-3 and C4-2 (WT) cells and their knockdown (siRNA) derivatives.