FLNA, a disulfidptosis-related gene, modulates tumor immunity and progression in colorectal cancer.

BACKGROUND: Disulfidptosis represents a novel type of regulated cell death induced by excessively high intracellular levels of cystine. Targeting disulfide imbalance is considered a promising treatment approach for colorectal cancer (CRC). However, the involvement of disulfidptosis in CRC immunotherapy is undefined. METHODS: Unsupervised clustering was applied to The Cancer Genome Atlas (TCGA) datasets to classify disulfidptosis-related phenotypes. The tumor microenvironment (TME) was characterized using diverse bioinformatics algorithms, including gene set variation analysis (GSVA) for pathway enrichment analysis and CIBERSORT for immune cell profiling. A disulfidptosis-related gene (DRG) signature was generated for stratifying CRC cases, and univariate Cox regression was utilized for identifying prognostic DRGs. Filamin A (FLNA) was pinpointed as a pivotal regulator of disulfidptosis, and its functional impacts on tumor progression and immunotherapy response were further investigated. RESULTS: Two different groups were determined on the basis of the built disulfidptosis-related signature (DRS), showing distinct clinical outcomes, as well as different pathway activation, drug sensitivity, and immune infiltration patterns. The high-DRS subgroup correlated with poorer prognosis, elevated immunosuppressive cell activity, and reduced cytotoxic immune cell infiltration. FLNA emerged as a critical mediator of disulfidptosis in CRC, with its knockdown suppressing tumor cell migration and invasion in vitro. The FLNA inhibitor PTI-125 attenuated tumor growth and epithelial-mesenchymal transition (EMT), while FLNA depletion reversed glucose-driven metastasis. Notably, combined glucose transporter 1 (GLUT1) inhibition and anti-programmed cell death protein 1 (PD-1) therapy enhanced CD8(+) T cell recruitment and suppressed EMT. CONCLUSIONS: This study elucidates the interplay between disulfidptosis and the CRC immune landscape, highlighting FLNA as a therapeutic target. These findings suggest that modulating disulfidptosis in conjunction with immunotherapy may offer a novel treatment paradigm for CRC.