To further confirm whether PBX1 could attenuate HF-MSCs senescence and apoptosis by upregulating SIRT1 and whether PBX1 could rescue SIRT1-knockdown-mediated HF-MSCs senescence and apoptosis, we overexpressed PBX1 and knocked down SIRT1 in HF-MSCs. This evidence concerns the gene PBX1 and hydrops fetalis.