These diverse roles in which HO-1 activity has been implicated in facilitating angiogenesis provide an opportunity to target HO-1 as an anti-angiogenic strategy, however, it should be noted that in several preclinical models using pharmacological inhibition or genetic inactivation of HO-1 did not result in tumor control (2, 26, 27), suggesting that HO-1 could play a modulatory rather than non-redundant role in this process which may also be TME-dependent. Here, HMOX1 is linked to neoplasm.