Ferritin Light Chain is Associated with M2-Polarized Macrophage Signatures and Poor Prognosis in Low-Grade Glioma

Despite maximal surgical resection and adjuvant chemoradiotherapy, glioma recurrence remains frequent, mandating robust prognostic biomarkers. Ferritin light chain (FTL) has been implicated in reprogramming the immune microenvironment and aggravating glioma progression. We therefore interrogated the prognostic value of FTL in low-grade glioma (LGG) and explored its association with immune microenvironment features. The specimens in this study were obtained from 14 patients with LGG. FTL messenger ribonucleic acid expression was quantified by quantitative real-time polymerase chain reaction, and protein levels were assessed by Western blotting. Bioinformatics analyses were conducted using The Cancer Genome Atlas-LGG and GTEx data sets, with validation in the Chinese Glioma Genome Atlas cohort. Immune infiltration patterns were characterized by integrated analyses of TIMER, CIBERSORT, TISIDB, and GSVA. Survival outcomes were evaluated using Cox multivariate models, with FTL expression dichotomized at the median. The results showed that FTL is highly expressed in LGG and is associated with shorter survival of LGG patients. Further analysis revealed that M2-tumor-associated macrophages (M2-TAMs) were positively correlated with FTL expression and were collectively associated with the overall survival of LGG patients. Additionally, FTL expression correlated with molecules and signaling pathways associated with M2-TAM polarization. High FTL expression is associated with both poor prognosis in LGG and M2-TAM-related immunosuppressive signatures.