Recently, Li et al1 have reported that vein injection of nanoliposome C6-ceramide, a cell membrane permeable form of ceramide, slows growth of liver tumors in mice, through suppressing tumor-associated macrophage functions and enhancing tumor antigen-specific CD8+ T-cell activity. Because tumor antigen-specific CD8+ T cells are seldom detectable in patients with liver cancers, studies on human immune cell responses inclusive of common CD8+ T cells regulated by nanoliposome C6-ceramide treatment will help to better understand the biofunctions of nanoliposome C6-ceramide and provide more direct evidence of potential immunotherapy for human cancers using C6-ceramide preparations.