RUNX3: a regulator of macrophage apoptosis with positive prognostic impact in sepsis.

BACKGROUND: Sepsis, a life-threatening condition, remains a leading cause of mortality globally. Transcription factors (TFs) play a pivotal role in its pathogenesis. RUNX3, a member of the RUNX family, has been implicated in immune regulation, but its function in sepsis remains unclear. OBJECTIVE: To determine whether RUNX3 expression is altered in sepsis and associated with patient prognosis, and to investigate its function and potential transcriptional regulatory targets in macrophages. METHODS: We analyzed RNA-seq data from sepsis patients to identify differentially expressed TFs and examined the prognostic impact of RUNX3 by Kaplan-Meier survival analysis. RUNX3 was stably overexpressed in RAW264.7 macrophages, and cell proliferation and apoptosis were assessed by EdU and flow cytometry assays. RNA-seq of RUNX3-overexpressing cells was performed to identify potential transcriptional regulatory targets, a subset of which was validated by RT-qPCR. RESULTS: RUNX3 expression was downregulated in sepsis patients, and low RUNX3 expression was associated with poor prognosis. RUNX3 overexpression promoted proliferation and inhibited apoptosis in RAW264.7 cells. Integrating RNA-seq with public RUNX3 binding data identified 89 potential transcriptional regulatory targets, among which Tgfbr3, Tgfbi, Il2rb, Gbp2, Gzmb, and Ptgds were confirmed as RUNX3-responsive by RT-qPCR. High expression of these targets was associated with favorable prognosis in sepsis patients. CONCLUSION: RUNX3 is closely associated with the prognosis of sepsis, and its overexpression promotes proliferation and suppresses apoptosis in macrophages, potentially by regulating downstream target genes, providing a novel perspective on sepsis pathogenesis.