摘要OBJECTIVE:To unmask the underlying mechanisms of Yisui granule(益髓颗粒,YSG)for the treatment of Myelodysplastic syndromes(MDS).METHODS:Our study used an SKM-1 mouse xenograft model of MDS to explore the anti-tumor potential of YSG and its safety,assess its effect on overall survival(OS),and evaluate whether its mechanism is associated with the demethylation of the secreted frizzled related protein 5(sFRP5)gene and suppressing Wnt/β-catenin pathway.Bisulfite amplicon sequencing was applied to detect the level of methylation of the sFRP5 gene;western blotting,immunofluorescence staining,and real-time Polymerase Chain Reaction were performed to detect DNA methyltransferase 1(DNMT1),sFRP5,and other Wnt/β-catenin pathway-related mRNA and protein expression.RESULTS:The results showed that high-dosage YSG exerted an anti-tumor effect similar to that of decitabine,improved OS,and reduced long-term adverse effects in the long term.Mechanically,YSG reduced the expression of DNMT1 methyltransferase,decreased the methylation,and increased the expression of the Wnt/β-catenin pathway antagonist-sFRP5.Furthermore,components of the Wnt/β-catenin pathway,including Wnt3a,β-catenin,c-Myc,and cyclinD1,were down-regulated in response to YSG,suggesting that YSG could treat MDS by demethylating the sFRP5 gene and suppressing the Wnt/β-catenin pathway.CONCLUSIONS:Our findings demonstrated that YSG could be used alone or in combination with decitabine to improve outcomes in the MDS animal model,providing an alternative solution for treating MDS.