CXCL1 and neoplasm: The growth of 4T1 cells is accompanied by the elevated secretion of cytokines such as G-CSF and chemokine (C–X–C motif) ligand 1 (CXCL1, KC) [40,41], but calcitriol and its analogs only significantly diminished CXCL1 during the early stage of tumor progression, not affecting the secretion of G-CSF in a significant manner.