CD44 and hepatocellular carcinoma: Another study used fluorescence-activated cell sorting to identify a small subpopulation of cells in HCC that had low proteasomal activity, a feature of stem cells, and further demonstrated that these cells had increased CD44 marker expression and tumorigenicity and could facilitate macrophage migration in vitro and metastatic potential in vivo through macrophage recruitment.97 This indicates that HCC cells with cancer stemness properties might cooperate with macrophages to facilitate tumour initiation.