Existing researches revealed that CXCR7 can increase the migration and invasion abilities of some malignant tumors in vitro, including liver cancer (Zheng et al., 2010; Lin et al., 2014; Neve Polimeno et al., 2015), pancreatic cancer (Guo et al., 2016), colon cancer (Xu et al., 2011), kidney cancer (Ierano et al., 2014), breast cancer (Wani et al., 2014), ovarian cancer (Yu et al., 2014), prostate cancer (Wang et al., 2008; Yang et al., 2018), bladder cancer (Hao et al., 2012), and glioma (Liu et al., 2013). Here, ACKR3 is linked to prostate cancer.