In contrast to their tumor-promoting abilities, MSCs can also suppress tumor growth via inhibition of proliferation-related signaling pathways such as AKT, PI3K, and Wnt, inhibition of cell cycle progression, downregulation of XIAP (X-linked inhibitor of apoptosis protein), and suppression of angiogenesis [40,41,42,43,44,45,46,47]. The gene discussed is XIAP; the disease is neoplasm.