As shown in Fig 3, HF alone induced cell apoptosis in a dose dependent manner (P ˂ 0.0001, one-way ANOVA, n = 3) that was similar to the results reported previously [15], and the combination of HF and RAPA (1 nM) further significantly increased the proportion of apoptotic cells (total annexin-V stained cells including both early and late apoptosis), from 8.28 ± 3.05% (0.625 nM HF alone) to 16.84 ± 2.11% (0.625 nM HF plus 1 nM RAPA), or from 13.88 ± 2.79% (2.5 nM HF alone) to 31.71 ± 3.81% (2.5 nM HF plus 1 nM RAPA) (HF alone vs. HF + RAPA: P ˂ 0.0001, two-way ANOVA, n = 3). Here, TRERF1 is linked to hydrops fetalis.