Xu et al. found that the CXCR4 receptor was involved in mediating the therapeutic effect of stromal cell‐derived factor‐1 in Parkinson's disease, suggesting that CXCR4 and its downstream pathway may be involved in the occurrence and development of Parkinson's disease and that CXCR4 could be used as a potential therapeutic target.31 Here, CXCR4 is linked to Parkinson disease.