TNFRSF11B and malignant colon neoplasm: While this secretion is comparable to that of the colon cancer CTC cell line CTC‐MCC‐41, CTC‐ITB‐01 does not secrete OPG (osteoprotegerin), EGFR (epidermal growth factor receptor) or FGF2 (fibroblast growth factor‐2) characteristic for CTC‐MCC‐41 (Appendix Fig S2) (Cayrefourcq et al, 2015).