EEC-derived EXOs can inhibit B-cell CLL/lymphoma 9 (BCL9) expression by delivering miRNA-30c to block the Wnt/β-catenin signaling pathway, thereby attenuating the tumor-like behavior of ectopic endometrial epithelial cells (ecto-EECs) in EM (Zhang et al., 2022c). This evidence concerns the gene BCL9 and neoplasm.