Moreover, a pro-inflammatory toll-like receptor ligand LL-37 has been linked to tumour-homing, as various tumour types (e.g., ovarian, breast, and lung cancer) demonstrated the overexpression of LL-37, which acted as a proliferative signal and pro-angiogenic factor and promoted the migration of MSCs into the tumour microenvironment, while its inhibition resulted in reduced tumour growth [18]. Here, CAMP is linked to lung cancer.