Lung tumor-derived exosomal induction of osteoclastogenesis is also linked with factors such as acceleration by C-X-C chemokine receptor type 4 (CXCR4) through self-potentiation and vascular cell adhesion molecule 1 (VCAM1) secretion [75], differential expression of the RANKL/RANK/OPG system [76], and activation of the EGF pathway by multiple myeloma-derived exosomes enriched in amphiregulin in the bone microenvironment [77]. Here, CXCR4 is linked to AL amyloidosis.