Previous studies have shown that ATF4 expression was regulated through ERK activation and eIF2α phosphorylation.[47] HF can inhibit AKT/mTOR signaling pathway.[48] Therefore, we performed the analysis of GO and KEGG pathway enrichment between COL1A1High and COL1ALow groups from public scRNA‐seq data of ovarian cancer, and found that AKT/mTOR signaling pathway might be involved in regulating progress of ECM (Figure 5G). Here, MTOR is linked to hydrops fetalis.