APAF1 and cancer: It has been found that the levels of miRNA-21 in the exosomes and tissue lysates derived from cancer-associated adipocytes (CAAs) and CAFs are significantly higher than those in ovarian cancer cells (Au Yeung et al., 2016), which can be transferred from both CAAs and CAFs to ovarian cancer cells via exosomes, where it exerts no influence on cell growth but induces cell invasion, suppresses cancer apoptosis by directly targeting APAF1, and contributes to paclitaxel chemoresistance.