Abstract
Hepatocellular carcinoma (HCC) remains a lethal malignancy with a persistently poor prognosis. While our previous studies established the anti-tumor function of Deoxyribonuclease I Like Protein 3 (DNASE1L3) in HCC, the underlying mechanisms involving the immune microenvironment are less understood. Here, we demonstrate that loss of DNASE1L3 accelerated HCC progression by impairing M1-type macrophage polarization in Dnase1l3 knockout (KO) mice, co-culture models, RNA-seq, and comprehensive molecular/cellular analyses. Mechanistically, DNASE1L3 deletion suppresses tumor-associated macrophages (TAMs) polarization toward the M1 phenotype and inhibits pyroptosis by attenuating the NLRP3 inflammasome/gasdermin D (GSDMD) pathway in vitro and in vivo, thereby reducing pyroptosis in HCC cells. This regulation involves impaired nuclear translocation of NF-κB p65. Crucially, NLRP3 agonism partially reversed DNase1L3-deletion-induced suppression of the NLRP3-GSDMD axis and restored M1 polarization. Our findings reveal DNase1L3 as a pivotal regulator of TAM phenotype via the NF-κB/NLRP3-GSDMD axis and highlight its potential for immunotherapy targeting macrophage reprogramming in HCC.