CXCR4 and neoplasm: Furthermore, CXCR4 stimulation by CXCL12 leads to the downstream activation of pathways like mitogen-activated protein kinases (MAPK), phosphatidylinositol-3-kinase (PI3K) pathway activation, and JAK/STAT pathways, ultimately leading to the homing of stem cells, hematopoietic development, angiogenesis, and tumor progression [186].