ICAM1 and neoplasm: Among the antitumor mechanisms mentioned in this paragraph, the immunoregulatory activity of cannabinoids is undoubtedly the one that requires further investigation and exploration, in the attempt to better explain the dual role of cannabinoids: while they may suppress immune responses that facilitate tumor control (via Th1 inhibition), they can also enhance tumor cell susceptibility to immune killing via ICAM-1 upregulation.