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

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.

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.

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.

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.

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.